WO2022036674A1

WO2022036674A1 - Window adjustment coding techniques for wireless communications systems

Info

Publication number: WO2022036674A1
Application number: PCT/CN2020/110455
Authority: WO
Inventors: Kangqi LIU; Changlong Xu; Jian Li; Liangming WU; Ruiming Zheng; Hao Xu
Original assignee: Qualcomm Incorporated
Priority date: 2020-08-21
Filing date: 2020-08-21
Publication date: 2022-02-24

Abstract

Methods, systems, and devices for wireless communications are described. Some window adjustment coding techniques may include a device, such as a base station, identifying a pool of source symbols for transmission. The device may encode, in accordance with a network coding scheme, a first set of source symbols from the pool of resources into a first set of encoded symbols, the first set of source symbols within a window having a first size. The device may transmit the first set of encoded symbols to one or more other devices. The device may adjust the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols. The second set of source symbols may include a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

Description

WINDOW ADJUSTMENT CODING TECHNIQUES FOR WIRELESS COMMUNICATIONS SYSTEMS

FIELD OF TECHNOLOGY

The following relates to wireless communications, including window adjustment coding techniques for wireless communications systems.

BACKGROUND

Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power) . Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may be referred to as New Radio (NR) systems. These systems may employ technologies such as code division multiple access (CDMA) , time division multiple access (TDMA) , frequency division multiple access (FDMA) , orthogonal frequency division multiple access (OFDMA) , or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) . A wireless multiple-access communications system may include one or more base stations or one or more network access nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE) .

Some wireless communications systems may support broadcasting of data from a transmitting device to receiving devices. In some cases, the transmitting device may refrain from transmitting subsequent data until each receiving device successfully receives and decodes the prior data, which may result in inefficient communications in the system.

SUMMARY

The described techniques relate to improved methods, systems, devices, and apparatuses that support window adjustment coding techniques for wireless communications systems. Generally, the described techniques enable devices of a wireless communications system to adjust a window for coding and transmission of data. For example, a base station may identify a pool of source symbols for broadcast transmission to one or more user equipments (UEs) . The base station may encode a portion of the pool of source symbols within a window having a first size. For example, the base station may obtain a first set of encoded symbols, using a network coding scheme, by encoding a first set of source symbols based on the first set of source symbols being within the window. The base station may transmit the first set of encoded symbols to the one or more UEs. The base station may adjust a size of the window from the first size to a second size. Accordingly, the base station may obtain a second set of encoded symbols using a second set of source symbols within the window having the second size. As an illustrative example, the base station may expand a size of the window such that the second set of source symbols includes the first set of source symbols and additional source symbols from the pool of source symbols. As another illustrative example, the base station may reduce a size of the window such that the second set of source symbols includes a portion of the first set of source symbols. Such window adjustment techniques may enable the base station to increase reception performance for at least a portion of the pool of source symbols, among other advantages.

A method of wireless communications at a base station is described. The method may include identifying a pool of source symbols for groupcast transmission via a network coding scheme, encoding, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size, transmitting the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission, and adjusting the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

An apparatus for wireless communications at a base station is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to identify a pool of source symbols for groupcast transmission via a network coding scheme, encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size, transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission, and adjust the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

Another apparatus for wireless communications at a base station is described. The apparatus may include means for identifying a pool of source symbols for groupcast transmission via a network coding scheme, encoding, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size, transmitting the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission, and adjusting the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

A non-transitory computer-readable medium storing code for wireless communications at a base station is described. The code may include instructions executable by a processor to identify a pool of source symbols for groupcast transmission via a network coding scheme, encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size, transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission, and adjust the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, adjusting the window may include operations, features, means, or instructions for expanding the window from the first size to the second size, the second size being greater than the first size.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for dividing the pool of source symbols into a set of subsets, where the first set of source symbols includes a first subset of the set of subsets and the second set of source symbols includes the first subset and a second subset of the set of subsets, where the first subset may have a priority that may be greater than that of the second subset.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, adjusting the window may include operations, features, means, or instructions for reducing the window from the first size to the second size, the first size being greater than the second size.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for dividing the pool of source symbols into a set of subsets, where the first set of source symbols includes a first subset of the set of subsets and a second subset of the set of subsets, where the second set of source symbols includes the first subset of the set of subsets, where the first subset may have a priority that may be greater than that of the second subset.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for encoding, in accordance with the network coding scheme, the second set of source symbols from the pool of source symbols into a second set of encoded symbols, the second set of source symbols within the window having the second size, and transmitting the second set of encoded symbols to the one or more UEs via groupcast transmission.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for adjusting the window from the second size to a third size for additional groupcast transmission of a third set of source symbols from the pool of source symbols, the third set of source symbols including the portion of the first set of source symbols, a portion of the second set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the network coding scheme includes a fountain coding scheme, a raptor coding scheme, a gaussian elimination process scheme, a belief propagation scheme, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the base station communicates with the one or more UEs via a multicast radio bearer or dual radio bearer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a wireless communications system for supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure.

FIG. 3 illustrates an example of a window adjustment coding scheme that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure.

FIG. 4 illustrates an example of a window adjustment coding scheme that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure.

FIG. 5 illustrates an example of a process flow that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure.

FIGs. 6 and 7 show block diagrams of devices that support window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure.

FIG. 8 shows a block diagram of a communications manager that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure.

FIG. 9 shows a diagram of a system including a device that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure.

FIGs. 10 through 12 show flowcharts illustrating methods that support window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Some wireless communication systems, such as fifth generation (5G) systems which may be referred to as New Radio (NR) systems, may support broadcast services (e.g., a multicast/broadcast service (MBS) ) where a transmitting device broadcasts (e.g., in addition or alternative to unicasting) data to one or more receiving devices. In some examples, the transmitting device and the receiving device may be examples of network nodes that exchange data packets via communications links. A network node, such as a user equipment (UE) , a base station, an integrated access and backhaul (IAB) relay node, or another wireless device, may encode symbols before transmission to improve reliability of a destination node successfully receiving the transmitted information. In some cases, encoded symbols may provide redundancy, which may be used to correct errors that result from the transmission environment (e.g., errors due to path loss or obstacles, among other examples of relatively poor channel conditions) .

If a transmitting device broadcasts encoded symbols associated with a first set of source symbols to one or more receiving devices, then each receiving device may obtain a different quantity of symbols such that a receiving device experiencing a high channel quality may successfully receive and decode the first set of source symbols before a receiving device having a low channel quality. In some examples, the transmitting device may refrain from encoding and transmitting a second set of source symbols until each receiving device successfully recovers the first set of source symbols. However, such examples may result in relatively inefficient communications (e.g., due to one or more receiving devices with poor channel conditions failing to successfully receive the first set of source symbols for a relatively long time) . Additionally or alternatively, some receiving devices may fail to decode the source symbols (e.g., rateless codes may stall due to missing or corrupt packets) , which may lead to an increase in an amount of encoded packets used for a successful recovery of the set of source packets.

In accordance with the techniques described herein, devices in a wireless communications system may implement one or more window adjustment coding techniques to decode or encode source symbols, which may result in improved efficiency for communications (e.g., the window adjustment coding techniques may enable receiving devices experiencing a relatively high channel quality to recover an increased quantity of source symbols, while receiving devices experiencing a low channel quality may realize an increased reliability of communications) . For example, a base station may identify a pool of source symbols for transmission to one or more UEs. The base station may divide the pool of source symbols into a quantity of subsets such that a first subset has a higher priority than a second subset, the second subset having a higher priority than a third subset, etc. The base station may obtain one or more sets of encoded symbols from the source symbols using a network coding scheme (e.g., using a rapid tornado (Raptor) code, among other examples of coding schemes) . For example, the base station may obtain a first set of encoded symbols by encoding a first set of source symbols within a window having a first size (e.g., the first size of the window may cover the first set of source symbols) . The base station may adjust the size of the window from the first size to a second size (e.g., a second size larger than the first size or smaller than the first size) . The base station may obtain a second set of encoded symbols by encoding a second set of source symbols within the window having a second size. In some examples, the base station may adjust the size of the window multiple times and transmit respective encoded symbols (e.g., encoded symbols corresponding to source symbols included in the window) .

In some examples, the base station may obtain the first set of encoded symbols using a window including a first subset of source symbols of the pool of source symbols. The base station may obtain subsequent sets of encoded symbols by expanding the window (e.g., by increasing the size of the window) . For example, the base station may expand the window from a first size to a second size, and the base station may encode the first subset of source symbols and a second subset of source symbols to obtain a second set of encoded symbols. The base station may transmit the sets of encoded symbols (e.g., the first set of encoded symbols, the second set of encoded symbols, etc. ) to one or more receiving devices (e.g., UEs) . For example, a receiving device may receive a first transmission including the first set of encoded symbols, a second transmission including the second set of encoded symbols, etc. Such techniques for expanding the coding window may enable the receiving device to have a relatively higher chance of successfully receiving and decoding the first subset of source symbols included in each transmission (e.g., a receiving device experiencing a low channel quality may be able to attempt recovering the first subset of source symbols from each transmission due to the first subset of source symbols being included in each window size) , while ensuring efficient communications (e.g., a receiving device experiencing a high channel quality may be able to successfully recover each subset of the pool of source symbols from a last transmission with a window size including the pool of source symbols) .

In some examples, the base station may obtain the first set of encoded symbols using a window with a first size including all source symbols of the pool of source symbols. The base station may obtain subsequent sets of encoded symbols by reducing a size of the window. For example, the base station may encode the pool of source symbols (e.g., each subset of the pool of source symbols may be included in the first size of the window) . The base station may transmit a respective set of encoded symbols to one or more receiving devices (e.g., UEs) . The base station may reduce the size of the window to a second size for a second transmission (e.g., transmitting a second set of encoded symbols that does not include a relatively lower priority subset of the pool of source symbols) , a third size for a third transmission, etc. Such techniques for reducing the coding window may enable the receiving device to have a relatively higher chance of successfully receiving and decoding the first subset of source symbols included in each transmission (e.g., a receiving device experiencing a low channel quality may be able to attempt recovering a relatively higher priority first subset of the pool of source symbols from each transmission due to the first subset of source symbols being included in each window size) , while ensuring efficient communications (e.g., a receiving device experiencing a high channel quality may be able to successfully recover each subset of the pool of source symbols from a first transmission with the first window size) , among other advantages.

Aspects of the disclosure are initially described in the context of wireless communications systems. Aspects of the disclosure are further described in the context of window adjustment coding schemes and a process flow. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to window adjustment coding techniques for wireless communications systems.

FIG. 1 illustrates an example of a wireless communications system 100 that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure. The wireless communications system 100 may include one or more base stations 105, one or more UEs 115, and a core network 130. In some examples, the wireless communications system 100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. In some examples, the wireless communications system 100 may support enhanced broadband communications, ultra-reliable (e.g., mission critical) communications, low latency communications, communications with low-cost and low-complexity devices, or any combination thereof.

The base stations 105 may be dispersed throughout a geographic area to form the wireless communications system 100 and may be devices in different forms or having different capabilities. The base stations 105 and the UEs 115 may wirelessly communicate via one or more communication links 125. Each base station 105 may provide a coverage area 110 over which the UEs 115 and the base station 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area over which a base station 105 and a UE 115 may support the communication of signals according to one or more radio access technologies.

The UEs 115 may be dispersed throughout a coverage area 110 of the wireless communications system 100, and each UE 115 may be stationary, or mobile, or both at different times. The UEs 115 may be devices in different forms or having different capabilities. Some example UEs 115 are illustrated in FIG. 1. The UEs 115 described herein may be able to communicate with various types of devices, such as other UEs 115, the base stations 105, or network equipment (e.g., core network nodes, relay devices, integrated access and backhaul (IAB) nodes, or other network equipment) , as shown in FIG. 1.

The base stations 105 may communicate with the core network 130, or with one another, or both. For example, the base stations 105 may interface with the core network 130 through one or more backhaul links 120 (e.g., via an S1, N2, N3, or other interface) . The base stations 105 may communicate with one another over the backhaul links 120 (e.g., via an X2, Xn, or other interface) either directly (e.g., directly between base stations 105) , or indirectly (e.g., via core network 130) , or both. In some examples, the backhaul links 120 may be or include one or more wireless links.

One or more of the base stations 105 described herein may include or may be referred to by a person having ordinary skill in the art as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB) , a next-generation NodeB or a giga-NodeB (either of which may be referred to as a gNB) , a Home NodeB, a Home eNodeB, or other suitable terminology.

A UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable terminology, where the “device” may also be referred to as a unit, a station, a terminal, or a client, among other examples. A UE 115 may also include or may be referred to as a personal electronic device such as a cellular phone, a personal digital assistant (PDA) , a tablet computer, a laptop computer, or a personal computer. In some examples, a UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communications (MTC) device, among other examples, which may be implemented in various objects such as appliances, or vehicles, meters, among other examples.

The UEs 115 described herein may be able to communicate with various types of devices, such as other UEs 115 that may sometimes act as relays as well as the base stations 105 and the network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, among other examples, as shown in FIG. 1.

The UEs 115 and the base stations 105 may wirelessly communicate with one another via one or more communication links 125 over one or more carriers. The term “carrier” may refer to a set of radio frequency spectrum resources having a defined physical layer structure for supporting the communication links 125. For example, a carrier used for a communication link 125 may include a portion of a radio frequency spectrum band (e.g., a bandwidth part (BWP) ) that is operated according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR) . Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information) , control signaling that coordinates operation for the carrier, user data, or other signaling. The wireless communications system 100 may support communication with a UE 115 using carrier aggregation or multi-carrier operation. A UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers according to a carrier aggregation configuration. Carrier aggregation may be used with both frequency division duplexing (FDD) and time division duplexing (TDD) component carriers.

Signal waveforms transmitted over a carrier may be made up of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM) ) . In a system employing MCM techniques, a resource element may consist of one symbol period (e.g., a duration of one modulation symbol) and one subcarrier, where the symbol period and subcarrier spacing are inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both) . Thus, the more resource elements that a UE 115 receives and the higher the order of the modulation scheme, the higher the data rate may be for the UE 115. A wireless communications resource may refer to a combination of a radio frequency spectrum resource, a time resource, and a spatial resource (e.g., spatial layers or beams) , and the use of multiple spatial layers may further increase the data rate or data integrity for communications with a UE 115.

The time intervals for the base stations 105 or the UEs 115 may be expressed in multiples of a basic time unit which may, for example, refer to a sampling period of T _s= 1/ (Δf _max·N _f) seconds, where Δf _max may represent the maximum supported subcarrier spacing, and N _f may represent the maximum supported discrete Fourier transform (DFT) size. Time intervals of a communications resource may be organized according to radio frames each having a specified duration (e.g., 10 milliseconds (ms) ) . Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023) .

Each frame may include multiple consecutively numbered subframes or slots, and each subframe or slot may have the same duration. In some examples, a frame may be divided (e.g., in the time domain) into subframes, and each subframe may be further divided into a number of slots. Alternatively, each frame may include a variable number of slots, and the number of slots may depend on subcarrier spacing. Each slot may include a number of symbol periods (e.g., depending on the length of the cyclic prefix prepended to each symbol period) . In some wireless communications systems 100, a slot may further be divided into multiple mini-slots containing one or more symbols. Excluding the cyclic prefix, each symbol period may contain one or more (e.g., N _f) sampling periods. The duration of a symbol period may depend on the subcarrier spacing or frequency band of operation.

A subframe, a slot, a mini-slot, or a symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communications system 100 and may be referred to as a transmission time interval (TTI) . In some examples, the TTI duration (e.g., the number of symbol periods in a TTI) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communications system 100 may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs) ) .

Physical channels may be multiplexed on a carrier according to various techniques. A physical control channel and a physical data channel may be multiplexed on a downlink carrier, for example, using one or more of time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. A control region (e.g., a control resource set (CORESET) ) for a physical control channel may be defined by a number of symbol periods and may extend across the system bandwidth or a subset of the system bandwidth of the carrier. One or more control regions (e.g., CORESETs) may be configured for a set of the UEs 115. For example, one or more of the UEs 115 may monitor or search control regions for control information according to one or more search space sets, and each search space set may include one or multiple control channel candidates in one or more aggregation levels arranged in a cascaded manner. An aggregation level for a control channel candidate may refer to a number of control channel resources (e.g., control channel elements (CCEs) ) associated with encoded information for a control information format having a given payload size. Search space sets may include common search space sets configured for sending control information to multiple UEs 115 and UE-specific search space sets for sending control information to a specific UE 115.

In some examples, a base station 105 may be movable and therefore provide communication coverage for a moving geographic coverage area 110. In some examples, different geographic coverage areas 110 associated with different technologies may overlap, but the different geographic coverage areas 110 may be supported by the same base station 105. In other examples, the overlapping geographic coverage areas 110 associated with different technologies may be supported by different base stations 105. The wireless communications system 100 may include, for example, a heterogeneous network in which different types of the base stations 105 provide coverage for various geographic coverage areas 110 using the same or different radio access technologies.

The wireless communications system 100 may be configured to support ultra-reliable communications or low-latency communications, or various combinations thereof. For example, the wireless communications system 100 may be configured to support ultra-reliable low-latency communications (URLLC) or mission critical communications. The UEs 115 may be designed to support ultra-reliable, low-latency, or critical functions (e.g., mission critical functions) . Ultra-reliable communications may include private communication or group communication and may be supported by one or more mission critical services such as mission critical push-to-talk (MCPTT) , mission critical video (MCVideo) , or mission critical data (MCData) . Support for mission critical functions may include prioritization of services, and mission critical services may be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, mission critical, and ultra-reliable low-latency may be used interchangeably herein.

In some examples, a UE 115 may also be able to communicate directly with other UEs 115 over a device-to-device (D2D) communication link 135 (e.g., using a peer-to-peer (P2P) or D2D protocol) . One or more UEs 115 utilizing D2D communications may be within the geographic coverage area 110 of a base station 105. Other UEs 115 in such a group may be outside the geographic coverage area 110 of a base station 105 or be otherwise unable to receive transmissions from a base station 105. In some examples, groups of the UEs 115 communicating via D2D communications may utilize a one-to-many (1: M) system in which each UE 115 transmits to every other UE 115 in the group. In some examples, a base station 105 facilitates the scheduling of resources for D2D communications. In other cases, D2D communications are carried out between the UEs 115 without the involvement of a base station 105.

The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or 5G core (5GC) , which may include at least one control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management function (AMF) ) and at least one user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management for the UEs 115 served by the base stations 105 associated with the core network 130. User IP packets may be transferred through the user plane entity, which may provide IP address allocation as well as other functions. The user plane entity may be connected to the network operators IP services 150. The network operators IP services 150 may include access to the Internet, Intranet (s) , an IP Multimedia Subsystem (IMS) , or a Packet-Switched Streaming Service.

Some of the network devices, such as a base station 105, may include subcomponents such as an access network entity 140, which may be an example of an access node controller (ANC) . Each access network entity 140 may communicate with the UEs 115 through one or more other access network transmission entities 145, which may be referred to as radio heads, smart radio heads, or transmission/reception points (TRPs) . Each access network transmission entity 145 may include one or more antenna panels. In some configurations, various functions of each access network entity 140 or base station 105 may be distributed across various network devices (e.g., radio heads and ANCs) or consolidated into a single network device (e.g., a base station 105) .

The wireless communications system 100 may operate using one or more frequency bands, typically in the range of 300 megahertz (MHz) to 300 gigahertz (GHz) . Generally, the region from 300 MHz to 3 GHz is known as the ultra-high frequency (UHF) region or decimeter band because the wavelengths range from approximately one decimeter to one meter in length. The UHF waves may be blocked or redirected by buildings and environmental features, but the waves may penetrate structures sufficiently for a macro cell to provide service to the UEs 115 located indoors. The transmission of UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to transmission using the smaller frequencies and longer waves of the high frequency (HF) or very high frequency (VHF) portion of the spectrum below 300 MHz.

The wireless communications system 100 may utilize both licensed and unlicensed radio frequency spectrum bands. For example, the wireless communications system 100 may employ License Assisted Access (LAA) , LTE-Unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed band such as the 5 GHz industrial, scientific, and medical (ISM) band. When operating in unlicensed radio frequency spectrum bands, devices such as the base stations 105 and the UEs 115 may employ carrier sensing for collision detection and avoidance. In some examples, operations in unlicensed bands may be based on a carrier aggregation configuration in conjunction with component carriers operating in a licensed band (e.g., LAA) . Operations in unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among other examples.

A base station 105 or a UE 115 may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of a base station 105 or a UE 115 may be located within one or more antenna arrays or antenna panels, which may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some examples, antennas or antenna arrays associated with a base station 105 may be located in diverse geographic locations. A base station 105 may have an antenna array with a number of rows and columns of antenna ports that the base station 105 may use to support beamforming of communications with a UE 115. Likewise, a UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, an antenna panel may support radio frequency beamforming for a signal transmitted via an antenna port.

The base stations 105 or the UEs 115 may use MIMO communications to exploit multipath signal propagation and increase the spectral efficiency by transmitting or receiving multiple signals via different spatial layers. Such techniques may be referred to as spatial multiplexing. The multiple signals may, for example, be transmitted by the transmitting device via different antennas or different combinations of antennas. Likewise, the multiple signals may be received by the receiving device via different antennas or different combinations of antennas. Each of the multiple signals may be referred to as a separate spatial stream and may carry bits associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords) . Different spatial layers may be associated with different antenna ports used for channel measurement and reporting. MIMO techniques include single-user MIMO (SU-MIMO) , where multiple spatial layers are transmitted to the same receiving device, and multiple-user MIMO (MU-MIMO) , where multiple spatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering, directional transmission, or directional reception, is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., a base station 105, a UE 115) to shape or steer an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining the signals communicated via antenna elements of an antenna array such that some signals propagating at particular orientations with respect to an antenna array experience constructive interference while others experience destructive interference. The adjustment of signals communicated via the antenna elements may include a transmitting device or a receiving device applying amplitude offsets, phase offsets, or both to signals carried via the antenna elements associated with the device. The adjustments associated with each of the antenna elements may be defined by a beamforming weight set associated with a particular orientation (e.g., with respect to the antenna array of the transmitting device or receiving device, or with respect to some other orientation) .

The wireless communications system 100 may be a packet-based network that operates according to a layered protocol stack. In the user plane, communications at the bearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based. A Radio Link Control (RLC) layer may perform packet segmentation and reassembly to communicate over logical channels. A Medium Access Control (MAC) layer may perform priority handling and multiplexing of logical channels into transport channels. The MAC layer may also use error detection techniques, error correction techniques, or both to support retransmissions at the MAC layer to improve link efficiency. In the control plane, the Radio Resource Control (RRC) protocol layer may provide establishment, configuration, and maintenance of an RRC connection between a UE 115 and a base station 105 or a core network 130 supporting radio bearers for user plane data. At the physical layer, transport channels may be mapped to physical channels.

The UEs 115 and the base stations 105 may support retransmissions of data to increase the likelihood that data is received successfully. Hybrid automatic repeat request (HARQ) feedback is one technique for increasing the likelihood that data is received correctly over a communication link 125. HARQ may include a combination of error detection (e.g., using a cyclic redundancy check (CRC) ) , forward error correction (FEC) , and retransmission (e.g., automatic repeat request (ARQ) ) . HARQ may improve throughput at the MAC layer in poor radio conditions (e.g., low signal-to-noise conditions) . In some examples, a device may support same-slot HARQ feedback, where the device may provide HARQ feedback in a specific slot for data received in a previous symbol in the slot. In other cases, the device may provide HARQ feedback in a subsequent slot, or according to some other time interval.

In some examples, devices of the wireless communications system 100 may implement mixed broadcast and unicast transmissions, for example, on a physical downlink shared channel (PDSCH) (e.g., with LTE single-cell point to multipoint (SC-PTM) as a baseline, the LTE SC-PTM associated with single cell broadcast, broadcast over PDSCH addressed with a G-RNTI, etc. ) . For examples, a mixed broadcast (MB) and unicast layer may receive a MB quality of service (QoS) flow over a MB-N3 tunnel, and the MB QoS flow may be mapped to a multicast radio bearer (MRB) or a data radio bearer (DRB) . Such examples may have a relatively close synergy with unicast (e.g., a device may be enabled with flexible switching between DRB and MRB, unicast assistance to MRB in lower layers, etc. ) . Additionally or alternatively, the wireless communications system may support one or more interfaces (e.g., N2 interface for control signaling for MB flow setup or modification, MB-N3 interface as a user plane interface for MB flow delivery over a GPRS tunneling protocol (GTP) , etc. ) .

In some examples, the wireless communications system 100 may support broadcast services where a transmitting device (e.g., a base station 105) broadcasts one or more symbols to one or more receiving devices (e.g., UEs 115) . In some examples, the base station 105 may encode (i.e., using a network coding technique) symbols before transmission to improve reliability of a destination node successfully receiving the transmitted information. In such examples, a base station 105 may implement window adjustment coding techniques. For example, a base station 105 may identify a set of source symbols for broadcast transmission. The base station 105 may divide the set of source symbols into one or more subsets such that a first subset has a higher priority than a second subset, the second subset having a higher priority than a third subset, etc. The base station 105 may obtain one or more sets of encoded symbols from the source symbols using a network coding scheme. In some examples, the base station 105 may obtain the encoded symbols using a window adjustment coding technique where the base station 105 uses a first set of source symbols within a window of a first size to obtain a first set of encoded symbols. The base station 105 may obtain a second set of encoded symbols using a second set of source symbols within a window of a second size. Accordingly, the base station 105 may adjust the size of the window to obtain additional sets of encoded symbols. Implementing window adjustment coding techniques may allow for an increased reliability of a broadcast services in the wireless communications system 100.

FIG. 2 illustrates an example of a wireless communications system 200 that supports window adjustment coding techniques for wireless communication systems in accordance with one or more aspects of the present disclosure. In some examples, the wireless communications system 200 may implement one or more aspects of a wireless communications system 100. The wireless communications system 200 may include a UE 115-a, a UE 115-b, and a UE 115-c which may be examples of a UE 115 as described with reference to FIG. 1. The wireless communications system 200 may also include a base station 105-a which may be an example of a base station 105 as described with reference to FIG. 1. The base station 105-a may be associated with a cell which provides wireless communications service with a coverage area 110-a.

The wireless communications system 200 may support network coding techniques, such as encoding algorithms with error correcting codes (e.g., forward error correction codes such as erasure correction codes) . Some examples of encoding algorithms with erasure correcting codes include fountain codes, such as Luby transform (LT) codes or Raptor codes. A fountain code may be an example of a rateless code, where a set of source symbols (e.g., K symbols) may be encoded as any quantity of encoding symbols (e.g., a quantity of symbols greater than K symbols) . For example, a device (e.g., a base station 105, a UE 115, etc. ) may use a rateless code to generate encoding symbols indefinitely from a set of source symbols. Encoding the source symbols may include combining one or more source symbols into each encoding symbol. An encoding process may include using a degree distribution, where the degree distribution represents a probability mass function of a set of degrees d _i (e.g., d ₁, d ₂, d ₃, etc. ) . ρ (i) may represent the probability that an index of an encoding symbol (e.g., the degree of the ith symbol represented as di) is equal to a degree d. In some cases of the encoding process, the degree d _i may represent the quantity of source symbols which may be combined into a given encoding symbol. In some examples, a Raptor code may use a small average degree.

A device may perform a decoding process to recover a set of source symbols from a set of encoded symbols. The decoding process may include identifying an encoding symbol associated with a single source symbol (i.e., has a degree of one) . The device may perform a logical exclusive OR (XOR) operation between the identified encoding symbol and each encoding symbol associated with the source symbol. The device may repeat the decoding process until each source symbol of the set of source symbols has been recovered. The device may recover the set of source symbols from a set of encoded symbols if an amount of encoded symbols is greater than the amount of source symbols. In some examples, the device may fail to recover the set of source symbols if the device cannot identify an encoding symbol associated with a single source symbol. Such a decoding scheme may be referred to as a belief propagation scheme. Additionally or alternatively, a device may perform a different decoding process, such as a gaussian elimination process (i.e., a gaussian elimination scheme) , among other examples.

As an illustrative example of network coding schemes, a transmitting device 205 may encode a set of K source symbols 220 using one or more network coding techniques. For examples, the transmitting device 205 may encode the K source symbols 220 using a rateless code (e.g., a fountain code, an LT code, a Raptor code, etc. ) . Encoding the K source symbols 220 may yield a set of N encoded symbols 225, which the transmitting device 205 may transmit to one or more receiving devices 215 (e.g., UEs 115-a, 115-b, and 115-c) . A receiving device may receive a set of L encoded symbols 230. In some examples, L may be less than or equal to N based on, for example, channel conditions experienced by the receiving device 215. If the L is greater than K, that is, if the set of L encoded symbols 230 is larger than the set of K source symbols 220, the received device 215 may successfully recover the set of source symbols 220.

In some examples, the wireless communications system 200 may support MBS communications services where the base station 105-a, which may be an example of a transmitting device 205, transmits encoded symbols to the UEs 115-a, 115-b, and 115-c which may be examples of received devices 215. In some examples, the base station 105-a may operate in RLC-UM, where the base station 105-a transmits encoded symbols without receiving feedback from the UEs 115-a, 115-b, or 115-c indicating whether the UEs 115-a, 115-b, or 115-c successfully recovered the source symbols. Accordingly, the base station 105-a may transmit a full set of encoded symbols. The UEs 115-a, 115-b, and 115-c may recover the source symbols using different numbers of encoded symbols based on channel conditions experienced by each UE 115. That is, each of the UEs 115-a, 115-b, and 115-c may successfully decode the source symbols if the number of successfully received symbols is greater than the number of source symbols (K) , but may unsuccessfully decode the source symbols if the number of successfully received symbols is less than the number of source symbols (K) . In such cases, depending on channel conditions and decoding success, some UEs 115 may successfully decode the transmitted symbols, and others may not.

To improve reliability or efficiency of communication, the base station 105-a may generate encoded symbols using a window adjustment coding technique. In some window adjust coding techniques, the base station 105-a may identify a pool (i.e., a set) of data source symbols for transmission to one or more of the UEs 115-a, 115-b, or 115-c. The base station 105-a may divide the set of source symbols into a number of subsets. For example, the base station 105-a may separate the set of K source symbols 220 into R subsets K _r where a subset K _i has a higher priority than a subset K _j if i is less than j. The base station 105-a may identify a window including one or more of the subsets of source symbols to be used for generating encoding symbols.

In some examples, the base station 105-a may identify a window of a first size where the window includes one subset of source symbols. Accordingly, the base station 105-a may encode source symbols included in the window to obtain a first set of encoded symbols. The base station 105-a may expand the window to a second size where the window includes both the first subset of source symbols and a second subset of source symbols. The base station 105-a may encode source symbols included in the window to obtain a second set of encoded symbols. The base station 105-a may adjust the window size until a window is obtained that includes each subset of source symbols. For example, the base station 105-a may expand the window until the window includes all symbols of the set of K source symbols 220. Accordingly, the base station 105-a may generate a set of encoded symbols that are associated with all symbols of the set of K source symbols 220.

In some examples, the base station 105-a may identify a window of a first size where the window includes all subsets of source symbols. Accordingly, the base station 105-amay encode source symbols included in the window to obtain a first set of encoded symbols. The base station 105-a may reduce the size of the window to a second size where the window includes all subsets of source symbols but one. The base station 105-a may encode source symbols included in the window to obtain a second set of encoded symbols. The base station 105-a may adjust the window size until a window is obtained that includes one subset of source symbols. It is noted that although adjusting the window by a size corresponding to one subset is described, the base station 105-a may adjust the window size by multiple subsets or by portions of a subset. Accordingly, the base station 105-a may adjust the window size by a different amount on each iteration of window adjustment.

The base station 105-a may transmit the sets of encoded symbols to one or more of the UEs 115-a, 115-b, or 115-c. For example, the base station 105-a may transmit the set of N encoded symbols 225 to the UEs 115-a, 115-b, or 115-c where the set of N encoded symbols 225 includes each set of encoded symbols generated using the window. Each set of encoded symbols may be associated with a subset of source symbols having a highest priority according to the separation scheme described herein. One or more of the UEs 115-a, 115-b, or 115-c may receive the set of L encoded symbols 225. The UEs 115-a, 115-b, or 115-c may successfully recover one or more subsets of source symbols if a generator matrix associated with each subset is of full rank. Accordingly, each set of encoded symbols may increase a probability that the UEs 115-a, 115-b, or 115-c may recover high priority source symbols.

In some examples, the UEs 115-a, 115-b, or 115-c may successful receive different numbers of encoded symbols (i.e., L may be different for each UE 115) . For example, if the UE 115-a experiences a higher channel quality than the UE 115-b (e.g., the UE 115-a may be an example of a UE 115 relatively closer to a center of the cell) , the UE 115-a may successfully receive a larger amount of encoded symbols. Accordingly, the UE 115-a may successfully recover a larger amount of source symbols than the UE 115-b which may correspond to the UE 115-a receiving a larger amount of data than the UE 115-b (e.g., the UE 115-b may be an example of a UE 115 relatively near the edge of the cell) .

As an illustrative example, the base station 105-a may be transmitting video streams to the UE 115-a and the UE 115-b. The window adjustment techniques described herein may enable the UE 115-b (e.g., a cell-edge UE 115) to receive a video stream with relatively low resolution (e.g., the higher priority subset of source symbols may be retransmitted in each window size, the higher priority subset including the low resolution data) . Additionally or alternatively, the UE 115-a may receive a video stream in a relatively higher resolution (e.g., the UE 115-a may be able to successfully decode relatively lower priority subsets of the source symbols in relatively larger window sizes, the relatively lower priority subsets corresponding to high resolution data) . For example, if the UE 115-a and the UE 115-b receive source symbols corresponding to a same video, the UE 115-a may receive the video in a higher resolution than the resolution received by the UE 115-b. It is noted that although described with reference to video data, the source symbols may correspond to any information transmitted by the base station 105-a. Implementing a window adjustment coding technique may allow for an increased reliability of broadcast services in the wireless communications system 200. In other words, the window adjustment techniques described herein may enable an increased decoding recovery probability for relatively high priority source symbols (e.g., relatively high priority subsets of the pool of source symbols) , among other advantages (e.g., while ensuring relatively efficient communications by enabling low-priority subsets to not be stalled until the high priority subsets are successfully received) .

FIG. 3 illustrates an example of a window adjustment coding scheme 300 that supports window adjustment coding techniques for wireless communication systems in accordance with one or more aspects of the present disclosure. In some examples, the window adjustment coding scheme 300 may implement aspects of a

wireless communications system

100 or 200 or any combination thereof as described with reference to FIGs. 1 and 2. For example, the window adjustment coding scheme 300 may be implemented by one or more base stations 105, one or more UEs 115, or any combination thereof as described with reference to FIG. 1. In some examples, the window adjustment coding scheme 300 may be implemented by a network node (e.g., a base station 105) to generate encoded symbols from one or more subsets of a set of source symbols 305.

The base station 105 may determine a pool of data source symbols 305 for transmission. The base station 105 may divide the source symbols 305 into one or more subsets 310. For example, the base station 105 may create a first subset 310-a which includes source symbols 305-a, 305-b, and 305-c, a second subset 310-b which includes source symbols 305-d, 305-e, and 305-f, etc., although it is to be understood that any quantity (i.e., number) of subsets may be used or that any quantity of symbols 305 may be included in a subset. The base station 105 may divide the pool of source symbols 305 into subsets until a last subset 310 (e.g., the subset 310-c including the source symbols 305-g, 305-h, and 305-i) . A number of subsets 310, and a number of source symbols 305 included in each subset 310 may correspond to an amount of source symbols 305 identified for transmission. In some examples, the subset 310-a may include source symbols 305 with a higher priority than source symbols 305 included in the subset 310-b. Accordingly, the subset 310-a may have a higher priority than the subset 310-b. Similarly, the subset 310-b may have a higher priority than a subset 310-c. In some other examples, the priorities may be different. For example, the subset 310-c may have a relatively high priority than the subset 310-b, the subset 310-b may have a relatively higher priority than the subset 310-a. etc.

The base station 105 may generate encoded symbols based on one or more of the subsets 310. For example, the base station 105 may determine a window 315-a that includes the subset 310-a. The base station 105 may generate a set of encoded symbols from the source symbols 305 included in the window 315-a. The base station 105 may expand the window 315-a to obtain the window 315-b that includes the subset 310-a and the subset 310-b. The base station 105 may use the window 315-b to generate a second set of encoded symbols that includes encoded symbols associated with the source symbols in the subset 310-a and the source symbols in the subset 310-b. The base station 105 may expand a window size until a window 315-c is obtained which includes all subsets 310. For example, the window 315-c may include the subsets 310-a, 310-b, and 310-c. The base station 105 may generate a set of encoded symbols from the source symbols included in the window 315-c. Accordingly, the set of encoded symbols may be associated with all of the identified source symbols. If one or more UEs 115 receive one or more sets of encoded symbols, UEs 115 experiencing a high channel quality may recover more source symbols 305 than UEs 115 experiencing a low channel quality. Implementing the window adjustment coding scheme 300 may allow for UEs 115 experiencing a high channel quality to recover additional source symbols while maintaining a high reliability of communications for UEs 115 experiencing a low channel quality.

Such techniques may result in one or more advantages. For example, by expanding the size of the window 315-a to the second size of the window 315-b, the base station 105 may provide redundancy for a relatively higher priority subset 310-a, while ensuring that transmission of relatively lower priority subsets 310 is not stalled until the first subset is successfully received by each UE (e.g., the base station may transmit encoded symbols corresponding to the source symbols 305-a, 305-b, and 305-c thrice, transmit encoded symbols corresponding to the relatively lower priority source symbols 305-d, 305-e, and 305-f twice, and transmit encoded symbols corresponding to the relatively lowest priority source symbols 305-g, 305-h, and 305-i once, although any quantity of symbols and transmissions may be used) .

FIG. 4 illustrates an example of a window adjustment coding scheme 400 that supports window adjustment coding techniques for wireless communication systems in accordance with one or more aspects of the present disclosure. In some examples, the window adjustment coding scheme 400 may implement aspects of a

wireless communications system

100 or 200, a window adjustment coding scheme 300, or any combination thereof as described with reference to FIGs. 1–3. For example, the window adjustment coding scheme 400 may be implemented by one or more base stations 105, one or more UEs 115, or any combination thereof as described with reference to FIG. 1. In some examples, the window adjustment coding scheme 400 may be implemented by a base station 105 to generate encoded symbols from one or more subsets of a set of source symbols 405.

The base station 105 may determine a pool of data source symbols 405 for transmission. The base station 105 may divide the source symbols 405 into one or more subsets 410. For example, the base station 105 may create a first subset 410-a which includes source symbols 405-a, 405-b, and 405-c, a second subset 410-b which includes source symbols 405-d, 405-e, and 405-f, etc., although it is to be understood that any quantity (i.e., number) of subsets may be used or that any quantity of symbols 405 may be included in a subset. The base station 105 may divide the pool of source symbols 405 into subsets until a last subset 410 (e.g., the subset 410-c including the source symbols 405-g, 405-h, and 405-i) . A number of subsets 410, and a number of source symbols 405 included in each subset 410 may correspond to an amount of source symbols 405 identified for transmission. In some examples, the subset 410-a may include source symbols 405 with a higher priority than source symbols 405 included in the subset 410-b. Accordingly, the subset 410-a may have a higher priority than the subset 410-b. Similarly, the subset 410-b may have a higher priority than a subset 410-c. In some other examples, the priorities may be different. For example, the subset 410-c may have a relatively high priority than the subset 410-b, the subset 410-b may have a relatively higher priority than the subset 410-a. etc.

The base station 105 may generate encoded symbols based on one or more of the subsets 410. For example, the base station 105 may determine a window 415-a that includes all of the subsets 410 (i.e., includes the subsets 410-a, 410-b, and 410-c) . The base station 105 may generate a set of encoded symbols from the source symbols 405 included in the window 415-a. The base station 105 may reduce the size of the window 415-a to obtain the window 315-b that includes the subsets 410-a and 410-b. The base station 105 may use the window 415-b to generate a second set of encoded symbols that includes encoded symbols associated with the source symbols in the subset 410-a and the source symbols in the subset 410-b. The base station 105 may reduce a window size until a window 415-c is obtained which includes only the subset 410-a. The base station 105 may generate a set of encoded symbols from the source symbols included in the window 415-c. Accordingly, each set of encoded symbols may be associated with the source symbols 305 included in the subset 410-a which may have a highest priority of the subsets 410. If one or more UEs 115 receive one or more sets of encoded symbols, UEs 115 experiencing a high channel quality may recover more source symbols 405 than UEs 115 experiencing a low channel quality. Implementing the window adjustment coding scheme 400 may allow for UEs 115 experiencing a high channel quality to recover additional source symbols while maintaining a high reliability of communications for UEs 115 experiencing a low channel quality.

Such techniques may result in one or more advantages. For examples, by reducing the size of the window 415-a to the second size of the window 415-b, the base station 105 may provide redundancy for relatively higher priority subsets 410-a and 410-b, while reducing retransmission of relatively lower priority subsets 410 (e.g., the base station may transmit encoded symbols corresponding to the source symbols 405-a, 405-b, and 405-c thrice, transmit encoded symbols corresponding to the relatively lower priority source symbols 405-d, 405-e, and 405-f twice, and transmit encoded symbols corresponding to the relatively lowest priority source symbols 405-g, 405-h, and 405-I once, although any quantity of symbols and transmissions may be used) .

FIG. 5 illustrates an example of a process flow 500 that supports window adjustment coding techniques for wireless communications systems in accordance with one or more aspects of the present disclosure. In some examples, the process flow 500 may implement aspects of a

wireless communications system

100 or 200, a window

adjustment coding scheme

300 or 400, or any combination thereof as described with reference to FIGs. 1–4. The process flow 500 may include a UE 115-d, a UE 115-e, and a base station 105-b which may be examples of the corresponding devices described herein. Alternative examples of the following may be implemented where some processes are performed in a different order than described or not performed at all. In some implementations, processes may include additional features not mentioned below, or further processes may be added.

At 505, the base station 105-b may identify a pool of source symbols for transmission. In some examples, the source symbols may include source symbols for groupcast or broadcast transmission.

At 510, the base station 105-b may divide the source symbols into one or more subsets. For example, the base station 105-b may identify a first subset of the pool of source symbols with a higher priority than a second subset which may include source symbols with a higher priority than a third subset, and so on, among other examples of dividing the pool of source symbols into one or more subsets.

At 515, the base station 105-b may encode source symbols included in a window having a first size to obtain a set of encoded symbols. For example, a window may have a first size including one or more of the subsets of source symbols (e.g., the window may include all of the subsets or the window may include a first subset of the subsets with a relatively higher priority) . Accordingly, the set of encoded symbols may correspond to the one or more subsets of source symbols.

At 520, the base station 105-b may transmit the set of encoded symbols to the UEs 115-d and 115-e. The UEs 115-d and 115-e may attempt to recover the source symbols associated with the set of encoded symbols. In some examples, the UE 115-d may recover a different amount of source symbols than the UE 115-e based on channel conditions experienced by each UE 115. For example, if the UE 115-d experiences a higher channel quality than the UE 115-e, the UE 115-d may successfully receive a larger amount of encoded symbols and so may recover a larger amount of source symbols.

At 525, the base station 105-b may adjust the window size. In some examples, the base station 105-b may expand the window size such that the window includes additional subsets of source symbols. In some examples, the base station 105-b may reduce the window size such that the window includes fewer subsets of source symbols. The window size may be adjusted such that the window includes source symbols with a highest priority each time the window is adjusted. For example, the window size may be adjusted such that relatively higher priority subsets are transmitted a higher quantity of times than relatively lower priority subsets, as described herein with reference to FIGs. 2–4.

At 530, the base station 105-b may encode source symbols included in the adjusted window to obtain a second set of encoded symbols. In some examples, the second set of encoded symbols may be associated with more source symbols than the first set of encoded symbols. For example, an expanded window may include one or more additional subsets of source symbols. In some examples, the second set of encoded symbols may be associated with fewer source symbols than the first set of encoded symbols based on the adjustment to the window size. For example, a reduced window may include one or more fewer subsets of source symbols.

At 535, the base station 105-b, the UE 115-d, and the UE 115-e may perform communications based on the window adjustment techniques. In some examples, the communications may include the base station 105-b transmitting additional sets of encoded symbols obtained from source symbols within windows of different sizes. For example, the base station 105-b may repeat 510 through 530 until the entire pool of resources has been transmitted, or until a quantity of transmissions equals the quantity of subsets. The UEs 115-b and UE 115-e may receive different amounts of encoded symbols and so may recover different amounts of source symbols. For example, if the UE 115-d experiences a higher channel quality than the UE 115-e, the UE 115-d may successfully receive a larger amount of encoded symbols and so may recover a larger amount of source symbols. Implementing the process flow 500 may allow for UEs 115 experiencing a high channel quality to recover additional source symbols while maintaining a high reliability of communications for UEs 115 experiencing a low channel quality.

FIG. 6 shows a block diagram 600 of a device 605 that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure. The device 605 may be an example of aspects of a base station 105 as described herein. The device 605 may include a receiver 610, a communications manager 615, and a transmitter 620. The device 605 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 610 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to window adjustment coding techniques for wireless communications systems, etc. ) . Information may be passed on to other components of the device 605. The receiver 610 may be an example of aspects of the transceiver 920 described with reference to FIG. 9. The receiver 610 may utilize a single antenna or a set of antennas.

The communications manager 615 may identify a pool of source symbols for groupcast transmission via a network coding scheme, encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size, transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission, and adjust the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof. The communications manager 615 may be an example of aspects of the communications manager 910 described herein.

The communications manager 615, or its sub-components, may be implemented in hardware, code (e.g., software or firmware) executed by a processor, or any combination thereof. If implemented in code executed by a processor, the functions of the communications manager 615, or its sub-components may be executed by a general-purpose processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure.

The communications manager 615, or its sub-components, may be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations by one or more physical components. In some examples, the communications manager 615, or its sub-components, may be a separate and distinct component in accordance with various aspects of the present disclosure. In some examples, the communications manager 615, or its sub-components, may be combined with one or more other hardware components, including but not limited to an input/output (I/O) component, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof in accordance with various aspects of the present disclosure.

The transmitter 620 may transmit signals generated by other components of the device 605. In some examples, the transmitter 620 may be collocated with a receiver 610 in a transceiver module. For example, the transmitter 620 may be an example of aspects of the transceiver 920 described with reference to FIG. 9. The transmitter 620 may utilize a single antenna or a set of antennas.

The communications manager 615 as described may be implemented to realize one or more potential advantages. Some implementations may allow the device 605 to implement a window adjustment coding technique for transmitting encoded symbols via a broadcast channel. Based on the window adjust coding techniques, the device 605 may support adjusting a size of a window to obtain one or more sets of encoded symbols such that receiving devices may successfully recover data. As such, the device 605 may exhibit improved reliability, reduced resource usage, or a decreased communications overhead, among other benefits.

FIG. 7 shows a block diagram 700 of a device 705 that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure. The device 705 may be an example of aspects of a device 605, or a base station 105 as described herein. The device 705 may include a receiver 710, a communications manager 715, and a transmitter 740. The device 705 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 710 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to window adjustment coding techniques for wireless communications systems, etc. ) . Information may be passed on to other components of the device 705. The receiver 710 may be an example of aspects of the transceiver 920 described with reference to FIG. 9. The receiver 710 may utilize a single antenna or a set of antennas.

The communications manager 715 may be an example of aspects of the communications manager 615 as described herein. The communications manager 715 may include a symbol manager 720, an encoding component 725, a symbol transmitter 730, and a window component 735. The communications manager 715 may be an example of aspects of the communications manager 910 described herein.

The symbol manager 720 may identify a pool of source symbols for groupcast transmission via a network coding scheme.

The encoding component 725 may encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size.

The symbol transmitter 730 may transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission.

The window component 735 may adjust the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

The transmitter 740 may transmit signals generated by other components of the device 705. In some examples, the transmitter 740 may be collocated with a receiver 710 in a transceiver module. For example, the transmitter 740 may be an example of aspects of the transceiver 920 described with reference to FIG. 9. The transmitter 740 may utilize a single antenna or a set of antennas.

FIG. 8 shows a block diagram 800 of a communications manager 805 that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure. The communications manager 805 may be an example of aspects of a communications manager 615, a communications manager 715, or a communications manager 910 described herein. The communications manager 805 may include a symbol manager 810, an encoding component 815, a symbol transmitter 820, and a window component 825. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses) .

The symbol manager 810 may identify a pool of source symbols for groupcast transmission via a network coding scheme.

The encoding component 815 may encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size.

In some examples, the encoding component 815 may encode, in accordance with the network coding scheme, the second set of source symbols from the pool of source symbols into a second set of encoded symbols, the second set of source symbols within the window having the second size. In some cases, the network coding scheme includes a fountain coding scheme, a raptor coding scheme, a gaussian elimination process scheme, a belief propagation scheme, or a combination thereof.

The symbol transmitter 820 may transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission. In some examples, the symbol transmitter 820 may transmit the second set of encoded symbols to the one or more UEs via groupcast transmission. In some cases, the base station communicates with the one or more UEs via a multicast radio bearer or dual radio bearer.

The window component 825 may adjust the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof. In some examples, the window component 825 may expand the window from the first size to the second size, the second size being greater than the first size. In some examples, the window component 825 may reduce the window from the first size to the second size, the first size being greater than the second size. In some examples, the window component 825 may adjust the window from the second size to a third size for additional groupcast transmission of a third set of source symbols from the pool of source symbols, the third set of source symbols including the portion of the first set of source symbols, a portion of the second set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

The dividing component 830 may divide the pool of source symbols into a set of subsets, where the first set of source symbols includes a first subset of the set of subsets and the second set of source symbols includes the first subset and a second subset of the set of subsets, where the first subset has a priority that is greater than that of the second subset. In some examples, dividing the pool of source symbols into a set of subsets, where the first set of source symbols includes a first subset of the set of subsets and a second subset of the set of subsets, where the second set of source symbols includes the first subset of the set of subsets, where the first subset has a priority that is greater than that of the second subset.

FIG. 9 shows a diagram of a system 900 including a device 905 that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure. The device 905 may be an example of or include the components of device 605, device 705, or a base station 105 as described herein. The device 905 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communications manager 910, a network communications manager 915, a transceiver 920, an antenna 925, memory 930, a processor 940, and an inter-station communications manager 945. These components may be in electronic communication via one or more buses (e.g., bus 950) .

The communications manager 910 may identify a pool of source symbols for groupcast transmission via a network coding scheme, encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size, transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission, and adjust the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

The network communications manager 915 may manage communications with the core network (e.g., via one or more wired backhaul links) . For example, the network communications manager 915 may manage the transfer of data communications for client devices, such as one or more UEs 115.

The transceiver 920 may communicate bi-directionally, via one or more antennas, wired, or wireless links as described above. For example, the transceiver 920 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 920 may also include a modem to modulate the packets and provide the modulated packets to the antennas for transmission, and to demodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 925. However, in some cases the device may have more than one antenna 925, which may be capable of concurrently transmitting or receiving multiple wireless transmissions.

The memory 930 may include RAM, ROM, or a combination thereof. The memory 930 may store computer-readable code 935 including instructions that, when executed by a processor (e.g., the processor 940) cause the device to perform various functions described herein. In some cases, the memory 930 may contain, among other things, a basic input/output system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor 940 may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some cases, the processor 940 may be configured to operate a memory array using a memory controller. In some cases, a memory controller may be integrated into processor 940. The processor 940 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 930) to cause the device 905 to perform various functions (e.g., functions or tasks supporting window adjustment coding techniques for wireless communications systems) .

The inter-station communications manager 945 may manage communications with other base station 105, and may include a controller or scheduler for controlling communications with UEs 115 in cooperation with other base stations 105. For example, the inter-station communications manager 945 may coordinate scheduling for transmissions to UEs 115 for various interference mitigation techniques such as beamforming or joint transmission. In some examples, the inter-station communications manager 945 may provide an X2 interface within an LTE/LTE-A wireless communication network technology to provide communication between base stations 105.

The code 935 may include instructions to implement aspects of the present disclosure, including instructions to support wireless communications. The code 935 may be stored in a non-transitory computer-readable medium such as system memory or other type of memory. In some cases, the code 935 may not be directly executable by the processor 940 but may cause a computer (e.g., when compiled and executed) to perform functions described herein.

FIG. 10 shows a flowchart illustrating a method 1000 that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure. The operations of method 1000 may be implemented by a base station 105 or its components as described herein. For example, the operations of method 1000 may be performed by a communications manager as described with reference to FIGs. 6 through 9. In some examples, a base station may execute a set of instructions to control the functional elements of the base station to perform the functions described below. Additionally or alternatively, a base station may perform aspects of the functions described below using special-purpose hardware.

At 1005, the base station may identify a pool of source symbols for groupcast transmission via a network coding scheme. The operations of 1005 may be performed according to the methods described herein. In some examples, aspects of the operations of 1005 may be performed by a symbol manager as described with reference to FIGs. 6 through 9.

At 1010, the base station may encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size. The operations of 1010 may be performed according to the methods described herein. In some examples, aspects of the operations of 1010 may be performed by an encoding component as described with reference to FIGs. 6 through 9.

At 1015, the base station may transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission. The operations of 1015 may be performed according to the methods described herein. In some examples, aspects of the operations of 1015 may be performed by a symbol transmitter as described with reference to FIGs. 6 through 9.

At 1020, the base station may adjust the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof. The operations of 1020 may be performed according to the methods described herein. In some examples, aspects of the operations of 1020 may be performed by a window component as described with reference to FIGs. 6 through 9.

FIG. 11 shows a flowchart illustrating a method 1100 that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure. The operations of method 1100 may be implemented by a base station 105 or its components as described herein. For example, the operations of method 1100 may be performed by a communications manager as described with reference to FIGs. 6 through 9. In some examples, a base station may execute a set of instructions to control the functional elements of the base station to perform the functions described below. Additionally or alternatively, a base station may perform aspects of the functions described below using special-purpose hardware.

At 1105, the base station may identify a pool of source symbols for groupcast transmission via a network coding scheme. The operations of 1105 may be performed according to the methods described herein. In some examples, aspects of the operations of 1105 may be performed by a symbol manager as described with reference to FIGs. 6 through 9.

At 1110, the base station may encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size. The operations of 1110 may be performed according to the methods described herein. In some examples, aspects of the operations of 1110 may be performed by an encoding component as described with reference to FIGs. 6 through 9.

At 1115, the base station may transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission. The operations of 1115 may be performed according to the methods described herein. In some examples, aspects of the operations of 1115 may be performed by a symbol transmitter as described with reference to FIGs. 6 through 9.

At 1120, the base station may expand the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second size being greater than the first size and the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof. The operations of 1120 may be performed according to the methods described herein. In some examples, aspects of the operations of 1120 may be performed by a window component as described with reference to FIGs. 6 through 9.

FIG. 12 shows a flowchart illustrating a method 1200 that supports window adjustment coding techniques for wireless communications systems in accordance with aspects of the present disclosure. The operations of method 1200 may be implemented by a base station 105 or its components as described herein. For example, the operations of method 1200 may be performed by a communications manager as described with reference to FIGs. 6 through 9. In some examples, a base station may execute a set of instructions to control the functional elements of the base station to perform the functions described below. Additionally or alternatively, a base station may perform aspects of the functions described below using special-purpose hardware.

At 1205, the base station may identify a pool of source symbols for groupcast transmission via a network coding scheme. The operations of 1205 may be performed according to the methods described herein. In some examples, aspects of the operations of 1205 may be performed by a symbol manager as described with reference to FIGs. 6 through 9.

At 1210, the base station may encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size. The operations of 1210 may be performed according to the methods described herein. In some examples, aspects of the operations of 1210 may be performed by an encoding component as described with reference to FIGs. 6 through 9.

At 1215, the base station may transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission. The operations of 1215 may be performed according to the methods described herein. In some examples, aspects of the operations of 1215 may be performed by a symbol transmitter as described with reference to FIGs. 6 through 9.

At 1220, the base station may reduce the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the first size being greater than the second size and the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof. The operations of 1220 may be performed according to the methods described herein. In some examples, aspects of the operations of 1220 may be performed by a window component as described with reference to FIGs. 6 through 9.

It should be noted that the methods described herein describe possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of the methods may be combined.

Example 1: A method for wireless communications at a base station, comprising: identifying a pool of source symbols for groupcast transmission via a network coding scheme; encoding, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size; transmitting the first set of encoded symbols to one or more UEs via groupcast transmission; and adjusting the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

Example 2: The method of example 1, wherein adjusting the window comprises: expanding the window from the first size to the second size, the second size being greater than the first size.

Example 3: The method of any of examples 1 or 2, further comprising: dividing the pool of source symbols into a plurality of subsets, wherein the first set of source symbols comprises a first subset of the plurality of subsets and the second set of source symbols comprises the first subset and a second subset of the plurality of subsets, wherein the first subset has a priority that is greater than that of the second subset.

Example 4: The method of example 1, wherein adjusting the window comprises: reducing the window from the first size to the second size, the first size being greater than the second size.

Example 5: The method of any of examples 1 or 4, further comprising: dividing the pool of source symbols into a plurality of subsets, wherein the first set of source symbols comprises a first subset of the plurality of subsets and a second subset of the plurality of subsets, wherein the second set of source symbols comprises the first subset of the plurality of subsets, wherein the first subset has a priority that is greater than that of the second subset.

Example 6: The method of any of examples 1 to 5, further comprising: encoding, in accordance with the network coding scheme, the second set of source symbols from the pool of source symbols into a second set of encoded symbols, the second set of source symbols within the window having the second size; and transmitting the second set of encoded symbols to the one or more UEs via groupcast transmission.

Example 7: The method of any of examples 1 to 6, further comprising: adjusting the window from the second size to a third size for additional groupcast transmission of a third set of source symbols from the pool of source symbols, the third set of source symbols including the portion of the first set of source symbols, a portion of the second set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.

Example 8: The method of any of examples 1 to 7, wherein the network coding scheme comprises a fountain coding scheme, a raptor coding scheme a gaussian elimination process scheme, a belief propagation scheme, or a combination thereof.

Example 9: The method of any of examples 1 to 8, wherein the base station communicates with the one or more UEs via a multicast radio bearer or dual radio bearer.

Example 10: An apparatus comprising at least one means for performing a method of any of examples 1 to 9.

Example 11: An apparatus for wireless communications comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method of any of examples 1 to 9.

Example 12: A non-transitory computer-readable medium storing code for wireless communications, the code comprising instructions executable by a processor to perform a method of any of examples 1 to 9.

Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may be described for purposes of example, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques may be applicable to various other wireless communications systems such as Ultra Mobile Broadband (UMB) , Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDM, as well as other systems and radio technologies not explicitly mentioned herein.

Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration) .

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, and not limitation, non-transitory computer-readable media may include random-access memory (RAM) , read-only memory (ROM) , electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) , or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of computer-readable medium. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD) , floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. ”

In the appended figures, similar components or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If just the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label, or other subsequent reference label.

The description set forth herein, in connection with the appended drawings, describes example configurations and does not represent all the examples that may be implemented or that are within the scope of the claims. The term “example” used herein means “serving as an example, instance, or illustration, ” and not “preferred” or “advantageous over other examples. ” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. These techniques, however, may be practiced without these specific details. In some instances, known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.

The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein, but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

A method for wireless communications at a base station, comprising:

identifying a pool of source symbols for groupcast transmission via a network coding scheme;

encoding, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size;

transmitting the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission; and

adjusting the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.
The method of claim 1, wherein adjusting the window comprises:

expanding the window from the first size to the second size, the second size being greater than the first size.
The method of claim 2, further comprising:

dividing the pool of source symbols into a plurality of subsets, wherein the first set of source symbols comprises a first subset of the plurality of subsets and the second set of source symbols comprises the first subset and a second subset of the plurality of subsets, wherein the first subset has a priority that is greater than that of the second subset.
The method of claim 1, wherein adjusting the window comprises:

reducing the window from the first size to the second size, the first size being greater than the second size.
The method of claim 4, further comprising:

dividing the pool of source symbols into a plurality of subsets, wherein the first set of source symbols comprises a first subset of the plurality of subsets and a second subset of the plurality of subsets, wherein the second set of source symbols comprises the first subset of the plurality of subsets, wherein the first subset has a priority that is greater than that of the second subset.
The method of claim 1, further comprising:

encoding, in accordance with the network coding scheme, the second set of source symbols from the pool of source symbols into a second set of encoded symbols, the second set of source symbols within the window having the second size; and

transmitting the second set of encoded symbols to the one or more UEs via groupcast transmission.
The method of claim 6, further comprising:

adjusting the window from the second size to a third size for additional groupcast transmission of a third set of source symbols from the pool of source symbols, the third set of source symbols including the portion of the first set of source symbols, a portion of the second set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.
The method of claim 1, wherein the network coding scheme comprises a fountain coding scheme, a raptor coding scheme, a gaussian elimination process scheme, a belief propagation scheme, or a combination thereof.
The method of claim 1, wherein the base station communicates with the one or more UEs via a multicast radio bearer or dual radio bearer.
An apparatus for wireless communications at a base station, comprising:

a processor,

memory coupled with the processor; and

instructions stored in the memory and executable by the processor to cause the apparatus to:

identify a pool of source symbols for groupcast transmission via a network coding scheme;

encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size;

transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission; and

adjust the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.
The apparatus of claim 10, wherein the instructions to adjust the window are executable by the processor to cause the apparatus to:

expand the window from the first size to the second size, the second size being greater than the first size.
The apparatus of claim 11, wherein the instructions are further executable by the processor to cause the apparatus to:

divide the pool of source symbols into a plurality of subsets, wherein the first set of source symbols comprises a first subset of the plurality of subsets and the second set of source symbols comprises the first subset and a second subset of the plurality of subsets, wherein the first subset has a priority that is greater than that of the second subset.
The apparatus of claim 10, wherein the instructions to adjust the window are executable by the processor to cause the apparatus to:

reduce the window from the first size to the second size, the first size being greater than the second size.
The apparatus of claim 13, wherein the instructions are further executable by the processor to cause the apparatus to:

divide the pool of source symbols into a plurality of subsets, wherein the first set of source symbols comprises a first subset of the plurality of subsets and a second subset of the plurality of subsets, wherein the second set of source symbols comprises the first subset of the plurality of subsets, wherein the first subset has a priority that is greater than that of the second subset.
The apparatus of claim 10, wherein the instructions are further executable by the processor to cause the apparatus to:

encode, in accordance with the network coding scheme, the second set of source symbols from the pool of source symbols into a second set of encoded symbols, the second set of source symbols within the window having the second size; and

transmit the second set of encoded symbols to the one or more UEs via groupcast transmission.
The apparatus of claim 15, wherein the instructions are further executable by the processor to cause the apparatus to:

adjust the window from the second size to a third size for additional groupcast transmission of a third set of source symbols from the pool of source symbols, the third set of source symbols including the portion of the first set of source symbols, a portion of the second set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.
The apparatus of claim 10, wherein the network coding scheme comprises a fountain coding scheme, a raptor coding scheme, a gaussian elimination process scheme, a belief propagation scheme, or a combination thereof.
The apparatus of claim 10, wherein the base station communicates with the one or more UEs via a multicast radio bearer or dual radio bearer.
An apparatus for wireless communications at a base station, comprising:

means for identifying a pool of source symbols for groupcast transmission via a network coding scheme;

means for encoding, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size;

means for transmitting the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission; and

means for adjusting the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.
The apparatus of claim 19, wherein the means for adjusting the window comprises:

means for expanding the window from the first size to the second size, the second size being greater than the first size.
The apparatus of claim 20, further comprising:

means for dividing the pool of source symbols into a plurality of subsets, wherein the first set of source symbols comprises a first subset of the plurality of subsets and the second set of source symbols comprises the first subset and a second subset of the plurality of subsets, wherein the first subset has a priority that is greater than that of the second subset.
The apparatus of claim 19, wherein the means for adjusting the window comprises:

means for reducing the window from the first size to the second size, the first size being greater than the second size.
The apparatus of claim 22, further comprising:

means for dividing the pool of source symbols into a plurality of subsets, wherein the first set of source symbols comprises a first subset of the plurality of subsets and a second subset of the plurality of subsets, wherein the second set of source symbols comprises the first subset of the plurality of subsets, wherein the first subset has a priority that is greater than that of the second subset.
The apparatus of claim 19, further comprising:

means for encoding, in accordance with the network coding scheme, the second set of source symbols from the pool of source symbols into a second set of encoded symbols, the second set of source symbols within the window having the second size; and

means for transmitting the second set of encoded symbols to the one or more UEs via groupcast transmission.
The apparatus of claim 24, further comprising:

means for adjusting the window from the second size to a third size for additional groupcast transmission of a third set of source symbols from the pool of source symbols, the third set of source symbols including the portion of the first set of source symbols, a portion of the second set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.
The apparatus of claim 19, wherein the network coding scheme comprises a fountain coding scheme, a raptor coding scheme, a gaussian elimination process scheme, a belief propagation scheme, or a combination thereof.
The apparatus of claim 19, wherein the base station communicates with the one or more UEs via a multicast radio bearer or dual radio bearer.
A non-transitory computer-readable medium storing code for wireless communications at a base station, the code comprising instructions executable by a processor to:

identify a pool of source symbols for groupcast transmission via a network coding scheme;

encode, in accordance with the network coding scheme, a first set of source symbols from the pool of source symbols into a first set of encoded symbols, the first set of source symbols being within a window having a first size;

transmit the first set of encoded symbols to one or more user equipments (UEs) via groupcast transmission; and

adjust the window from the first size to a second size for additional groupcast transmission of a second set of source symbols from the pool of source symbols, the second set of source symbols including a portion of the first set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.
The non-transitory computer-readable medium of claim 28, wherein the instructions to adjust the window are executable to:

expand the window from the first size to the second size, the second size being greater than the first size.
The non-transitory computer-readable medium of claim 29, wherein the instructions are further executable to:

divide the pool of source symbols into a plurality of subsets, wherein the first set of source symbols comprises a first subset of the plurality of subsets and the second set of source symbols comprises the first subset and a second subset of the plurality of subsets, wherein the first subset has a priority that is greater than that of the second subset.
The non-transitory computer-readable medium of claim 28, wherein the instructions to adjust the window are executable to:

reduce the window from the first size to the second size, the first size being greater than the second size.
The non-transitory computer-readable medium of claim 31, wherein the instructions are further executable to:

divide the pool of source symbols into a plurality of subsets, wherein the first set of source symbols comprises a first subset of the plurality of subsets and a second subset of the plurality of subsets, wherein the second set of source symbols comprises the first subset of the plurality of subsets, wherein the first subset has a priority that is greater than that of the second subset.
The non-transitory computer-readable medium of claim 28, wherein the instructions are further executable to:

encode, in accordance with the network coding scheme, the second set of source symbols from the pool of source symbols into a second set of encoded symbols, the second set of source symbols within the window having the second size; and

transmit the second set of encoded symbols to the one or more UEs via groupcast transmission.
The non-transitory computer-readable medium of claim 33, wherein the instructions are further executable to:

adjust the window from the second size to a third size for additional groupcast transmission of a third set of source symbols from the pool of source symbols, the third set of source symbols including the portion of the first set of source symbols, a portion of the second set of source symbols, additional source symbols from the pool of source symbols, or a combination thereof.
The non-transitory computer-readable medium of claim 28, wherein the network coding scheme comprises a fountain coding scheme, a raptor coding scheme, a gaussian elimination process scheme, a belief propagation scheme, or a combination thereof.
The non-transitory computer-readable medium of claim 28, wherein the base station communicates with the one or more UEs via a multicast radio bearer or dual radio bearer.