WO2021196159A1

WO2021196159A1 - Method and apparatus for selecting destination

Info

Publication number: WO2021196159A1
Application number: PCT/CN2020/083202
Authority: WO
Inventors: Jing HAN; Zhennian SUN; Haiming Wang; Lianhai WU; Jie Hu
Original assignee: Lenovo (Beijing) Limited
Priority date: 2020-04-03
Filing date: 2020-04-03
Publication date: 2021-10-07

Abstract

The subject disclosure relates to a method and apparatus for selecting a destination. One embodiment of the subject disclosure provides a method performed on a User Equipment (UE) for selecting a destination, comprising: selecting the destination from multiple destinations having sidelink connections with the UE based on latency requirements of the multiple destinations, wherein the multiple destinations are to receive one or more Media Access Control Control Elements (MAC CEs) and one or more logical channels from the UE; and performing, on the UE, transmission to the selected destination.

Description

METHOD AND APPARATUS FOR SELECTING DESTINATION

TECHNICAL FIELD

The subject application relates to sidelink communication, and more specifically relates to selecting a destination during sidelink communication.

BACKGROUND OF THE INVENTION

Vehicle to everything (V2X) has been introduced into 5G wireless communication technology. In terms of a channel structure of V2X communication, a direct link between two user equipments (UEs) is called a sidelink (SL) . Sidelink is a long-term evolution (LTE) feature introduced in 3GPP Release 12, and enables a direct communication between proximal UEs, and data does not need to go through a base station (BS) or a core network.

In order to enhance the reliability and reduce latency of the sidelink communication, it is desirable to further improve the inter-UE coordination.

SUMMARY

One embodiment of the subject application provides a method performed on a UE for selecting a destination, comprising: selecting the destination from multiple destinations having sidelink connections with the UE based on latency requirements of the multiple destinations, wherein the multiple destinations are to receive one or more media access control control elements (MAC CEs) and one or more logical channels from the UE; and performing, on the UE, transmission to the selected destination.

Another embodiment of the subject application provides a method performed on a UE for selecting a prioritized transmission, comprising: selecting the prioritized transmission from a uplink transmission to a BS and one or multiple sidelink transmissions from the UE based on latency requirements of the uplink transmission and one or multiple sidelink transmissions; and performing the prioritized transmission.

Yet another embodiment of the subject application provides an apparatus, comprising: a non-transitory computer-readable medium having stored thereon computer-executable instructions; a receiving circuitry; a transmitting circuitry; and a processor coupled to the non-transitory computer-readable medium, the receiving circuitry and the transmitting circuitry, wherein the computer-executable instructions cause the processor to implement the method performed on a UE for selecting a destination, comprising: selecting the destination from multiple destinations having sidelink connections with the UE based on latency requirements of the multiple destinations, wherein the multiple destinations are to receive one or more MAC CEs and one or more logical channels from the UE; and performing, on the UE, transmission to the selected destination.

Still another embodiment of the subject application provides an apparatus, comprising: a non-transitory computer-readable medium having stored thereon computer-executable instructions; a receiving circuitry; a transmitting circuitry; and a processor coupled to the non-transitory computer-readable medium, the receiving circuitry and the transmitting circuitry, wherein the computer-executable instructions cause the processor to implement the method performed on a UE for selecting a prioritized transmission, comprising: selecting the prioritized transmission from a uplink transmission to a BS and one or multiple sidelink transmissions from the UE based on latency requirements of the uplink transmission and one or multiple sidelink transmissions; and performing the prioritized transmission.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to describe the manner in which advantages and features of the application can be obtained, a description of the application is rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. These drawings depict only example embodiments of the application and are not therefore to be considered limiting of its scope.

Figure 1 illustrates an exemplary V2X communication system 100 in accordance with some embodiments of the present disclosure.

Figures 2 (a) and 2 (b) illustrate embodiments of destination selection based on the latency requirement of the logical channels and the MAC CE in accordance with some embodiments of the present disclosure.

Figures 3 (a) and 3 (b) illustrate embodiments for destination selection when multiple destinations have both logical channels and sidelink channel state information (CSI) reporting MAC CE has the same priority in accordance with some embodiments of the present disclosure.

Figure 4 illustrates an embodiment of destination selection during the UL/SL prioritization procedure in accordance with some embodiments of the present disclosure.

Figure 5 illustrates a method performed by a UE for wireless communication according to a preferred embodiment of the subject disclosure.

Figure 6 illustrates a method performed by a UE for wireless communication according to a preferred embodiment of the subject disclosure.

Figure 7 illustrates a block diagram of a UE according to the embodiments of the subject disclosure.

DETAILED DESCRIPTION

The detailed description of the appended drawings is intended as a description of the preferred embodiments of the present invention, and is not intended to represent the only form in which the present invention may be practiced. It should be understood that the same or equivalent functions may be accomplished by different embodiments that are intended to be encompassed within the spirit and scope of the present invention.

Reference will now be made in detail to some embodiments of the present application, examples of which are illustrated in the accompanying drawings. To facilitate understanding, embodiments are provided under specific network architecture and new service scenarios, such as 3GPP 5G, 3GPP LTE Release 8 and so on. It is contemplated that along with developments of network architectures and new service scenarios, all embodiments in the present application are also applicable to similar technical problems; and moreover, the terminologies recited in the present application may change, which should not affect the principle of the present application.

UE (s) under new radio (NR) V2X scenario may be referred to as V2X UE (s) . A V2X UE, which transmits data according to sidelink resource (s) scheduled by a BS, may be referred to as a UE for transmitting, a transmitting UE, a transmitting V2X UE, a Tx UE, a V2X Tx UE, a SL Tx UE, or the like. A V2X UE, which receives data according to sidelink resource (s) scheduled by a BS, may be referred to as a UE for receiving, a receiving UE, a receiving V2X UE, a Rx UE, a V2X Rx UE, a SL Rx UE, or the like.

V2X UE (s) may include computing devices, such as desktop computers, laptop computers, personal digital assistants (PDAs) , tablet computers, smart televisions (e.g., televisions connected to the Internet) , set-top boxes, game consoles, security systems (including security cameras) , vehicle on-board computers, network devices (e.g., routers, switches, and modems) , internet of things (IoT) devices, or the like.

According to some embodiments of the present application, V2X UE (s) may include a portable wireless communication device, a smart phone, a cellular telephone, a flip phone, a device having a subscriber identity module, a personal computer, a selective call receiver, or any other device that is capable of sending and receiving communication signals on a wireless network.

According to some embodiments of the present application, V2X UE (s) includes wearable devices, such as smart watches, fitness bands, optical head-mounted displays, or the like. Moreover, V2X UE (s) may be referred to as a subscriber unit, a mobile, a mobile station, a user, a terminal, a mobile terminal, a wireless terminal, a fixed terminal, a subscriber station, a user terminal, or a device, or described using other terminology used in the art. V2X UE (s) may communicate directly with BS (s) via uplink (UL) communication signals.

A BS under NR V2X scenario may be referred to as a base unit, a base, an access point, an access terminal, a macro cell, a Node-B, an enhanced Node B (eNB) , a gNB, a Home Node-B, a relay node, a device, a remote unit, or by any other terminology used in the art. A BS may be distributed over a geographic region. Generally, a BS is a part of a radio access network that may include one or more controllers communicably coupled to one or more corresponding base stations.

A BS is generally communicably coupled to one or more packet core networks (PCN) , which may be coupled to other networks, like the packet data network (PDN) (e.g., the Internet) and public switched telephone networks, among other networks. These and other elements of radio access and core networks are not illustrated but are well known generally by those having ordinary skill in the art. For example, one or more BSs may be communicably coupled to a mobility management entity (MME) , a serving gateway (SGW) , and/or a packet data network gateway (PGW) .

A BS may serve a number of V2X UEs within a serving area, for example, a cell or a cell sector via a wireless communication link. A BS may communicate directly with one or more of V2X UEs via communication signals. For example, a BS may serve V2X UEs within a macro cell.

Sidelink communication between a Tx UE and a Rx UE under NR V2X scenario includes groupcast communication, unicast communication, or broadcast communication.

Embodiments of the present application may be provided in a network architecture that adopts various service scenarios, for example but is not limited to, 3GPP 3G, LTE, LTE-Advanced (LTE-A) , 3GPP 4G, 3GPP 5G NR (new radio) , 3GPP LTE Release 12 and onwards, etc. It is contemplated that along with the 3GPP and related communication technology development, the terminologies recited in the present application may change, which should not affect the principle of the present application.

Figure 1 illustrates an exemplary V2X communication system in accordance with some embodiments of the present application.

As shown in Figure 1, the V2X communication system includes a base station, i.e., BS 102 and some V2X UEs, i.e., UE 101-A, UE 101-B, and UE 101-C. UE 101-A and UE 101-B are within the coverage of BS 102, and UE 101-C is not. UE 101-A, UE 101-B, and UE 101-C are configured to perform sidelink unicast transmission, sidelink groupcast transmission, or sidelink broadcast transmission. It is contemplated that, in accordance with some other embodiments of the present application, a V2X communication system may include more BSs, and more or fewer V2X UEs. Moreover, it is contemplated that names of V2X UEs (which represent a Tx UE, a Rx UE, and etc. ) as illustrated and shown in Figure 1 may be different, e.g., UE 101c, UE 104f, and UE 108g or the like.

In addition, although each V2X UE as shown in Figure 1 is illustrated in the shape of a car, it is contemplated that a V2X communication system may include any type of UE (e.g., a roadmap device, a cell phone, a computer, a laptop, IoT (internet of things) device or other type of device) in accordance with some other embodiments of the present application.

According to some embodiments of Figure 1, UE 101-A functions as a Tx UE, and UE 101-B and UE 101-C function as a Rx UE. UE 101-A may exchange V2X messages with UE 101-B, or UE 101-C through a sidelink, for example, PC5 interface as defined in 3GPP TS 23.303. UE 101-A may transmit information or data to other UE (s) within the V2X communication system, through sidelink unicast, sidelink groupcast, or sidelink broadcast. For instance, UE 101-A transmits data to UE 101-B in a sidelink unicast session. UE 101-A may transmit data to UE 101-B and UE 101-C in a groupcast group by a sidelink groupcast transmission session. Also, UE 102 may transmit data to UE 101-B and UE 101-C by a sidelink broadcast transmission session.

Alternatively, according to some other embodiments of Figure 1, UE 101-B functions as a Tx UE and transmits V2X messages, UE 101-A functions as a Rx UE and receives the V2X messages from UE 101-B.

Both UE 101-A and UE 101-B in the embodiments of Figure 1 may transmit information to BS 102 and receive control information from BS 102, for example, via NR Uu interface. BS 102 may define one or more cells, and each cell may have a coverage area. As shown in Figure 1, both UE 101-A and UE 101-B are within a coverage of BS 102, and UE 101-C is not.

BS 102 as illustrated and shown in Figure 1 is not a specific base station, but may be any base station (s) in the V2X communication system. For example, if the V2X communication system includes two BSs 102, UE 101-A being within a coverage area of any one the two BSs 102 may be called as a case that UE 101-A is within a coverage of BS 102 in the V2X communication system; and only UE 101-A being outside of coverage area (s) of both BSs 102 can be called as a case that UE 101-A is outside of the coverage of BS 102 in the V2X communication system.

When a UE is performing sidelink transmission, it may have multiple destinations. In order to decide the sequence for the multiple sidelink transmissions, different priorities are defined for different types of sidelink transmissions.

In TS 38.321, select a destination associated with one of unicast, groupcast and broadcast, having the logical channel or the MAC CE with the highest priority, among the logical channels that satisfy all the following conditions and MAC CE (s) , if any, for the SL grant associated to the SCI:

i. SL data is available for transmission; and

ii. SBj > 0, in case there is any logical channel having SBj > 0; and

iii. sl-configuredSLGrantType1Allowed, if configured, is set to true in case the SL grant is a Configured Grant Type 1.

The priority value of the CSI Reporting MAC-CE is set to a fixed value, '1' , and is prioritized between PC5-RRC/Ssignaling and sidelink data logical channels in SL Logical Channel Prioritization (LCP) . The priority value of PC5-RRC/Ssignaling is '0' , and the priority value of the logical channels ranges from '1' to '8' . Generally, the priority level is inversely proportional to the priority value, for instance, the priority value '1' has the higher priority level than the priority value '2' .

In view of the above, since priority value of sidelink CSI MAC CE is 1, which is always larger than or equal to the priority value of the logical channels, which have priority value from1 to 8, if the Tx UE selects the destination based on the priority value, then the destination having MAC CE is always selected under normal case. Suppose there are two destinations, the first destination has sidelink CSI reporting MAC CE and logical channel with priority ≤ 6, and the second destination has logical channel with priority ≤ 2. The Tx UE would select the first destination since the first destination has MAC CE, which renders the priority value of the first destination being '1' . In this case, although the data to be transmitted to second destination is more important than the data to be transmitted to the first destination, the first destination is selected, i.e., the sidelink transmission to the first destination is handled.

On the other hand, the sidelink CSI reporting MAC CE has latency requirement, i.e. latency bound, which is configured by the peer UE. The value of the latency bound of sidelink CSI reporting MAC CE ranges from 3ms to 20ms.

In some cases, the traffic to the destination having MAC CE might be less urgent than the traffic to other destinations having logical channels, therefore, it is desirable to select the destination of sidelink transmission only not based on the priority value, but also based on the latency requirement regarding the traffics.

There are several approaches for the Tx UE to select from multiple destinations.

The first approach is to select the destination based on the latency requirement of the logical channels. In this solution, destinations which include SL CSI reporting MAC CE are ignored, and only the destinations with logical channels are considered. During destination selection, if a logical channel with highest priority also has the packet delay budget (PDB) value lower than a configured threshold, the destination with highest priority will be selected, and the destinations having SL CSI reporting MAC CE will be ignored.

For example, Figure 2 (a) illustrates an example of destination selection based on the latency requirement of the logical channels. In Figure 2 (a) , destination 1 having SL CSI reporting MAC CE is ignored during the selection, and the latency bound x ₁ is not considered. Destination 2 includes logical channel with a priority 2, and destination 3 includes logical channel with a priority 5. Therefore, the highest priority is 2, which means that destination 2 is a logical channel with the highest priority. The latency requirement, i.e. the PDB value, of the logical channel with the highest priority is y ₂ ms, if y ₂ is smaller than a configured threshold, then destination 2 will be selected. The configured threshold may be represented with "lch-PDBthreshold" . Then, if y ₂ < lch-PDBthreshold, destination 2 will be selected during destination selection in LCP, and destination 1 which has SL CSI reporting MAC CE is ignored. This means if y ₂ < lch-PDBthreshold, all destinations contains SL CSI reporting MAC CE will not be considered during the destination selection in LCP.

The second approach is to select the destination based on the latency requirement of the sidelink CSI reporting MAC CE. In this solution, not all destinations which include sidelink CSI reporting MAC CE are considered, and only the destinations with sidelink CSI reporting MAC CE which latency bound value fulfill an condition are considered. During destination selection, if sidelink CSI reporting MAC CE has lower latency bound value than a threshold which is configured by network, peer UE or pre-configuration, the associated destination (s) of sidelink CSI reporting MAC CE (s) will be considered during destination selection procedure for MAC Protocol Data Unit (PDU) .

For example, Figure 2 (b) illustrates an example of destination selection based on the latency requirement of the sidelink CSI reporting MAC CE. In Figure 2 (b) , destination 1 includes sidelink CSI reporting MAC CE, and the latency bound is x ₁. Destination 2 includes sidelink CSI reporting MAC CE, and the latency bound is x ₂. Destination 3 includes logical channel with a priority 5.

A threshold "macce-PDBthreshold" is configured. Then if x ₁ ≥macce-PDBthreshold, destination 1 will not be considered during destination selection in LCP. Else if x ₁ < macce-PDBthreshold and x ₂ ≥ macce-PDBthreshold, reuse existing procedure that destination 1 with sidelink CSI reporting MAC CE is considered during destination selection in LCP, i.e. the destination selection is then based on priority level of destination 1 and destination 3. If both x ₁ and x ₂ <macce-PDBthreshold, then it is up to UE implementation to select a destination between destination 1 and destination 2.

The third approach is to select the destination based on the latency requirements of both the sidelink CSI reporting MAC CE and the logical channel with highest priority.

For destination selection, for sidelink CSI reporting MAC CE, not only consider priority value, but also consider PDB between sidelink CSI reporting MAC CE and logical channel with the highest priority among the logical channels. If sidelink CSI reporting MAC CE has equal or higher latency requirement value than logical channel with highest priority, the associated destination (s) of sidelink CSI reporting MAC CE (s) will not be selected as the destination for MAC PDU.

For example, in Figure 2 (a) , destination 1 has sidelink CSI reporting MAC CE, which latency bound is x ₁ ms, and the latency bound or PDB of highest priority logical channel among all other destinations is y ₂ ms. Then if x ₁ ≥ y ₂, destination 1 will not be considered during destination selection in LCP. If x ₁ < y ₂, reuse existing procedure that destination 1 with sidelink CSI reporting MAC CE is considered during destination selection in LCP.

After receive the configuration of latency bound of sidelink CSI reporting MAC CE from initiating UE, the peer UE will report latency bound of sidelink CSI reporting MAC CE to the BS in SidelinkUEInformation. The latency bound of sidelink CSI reporting MAC CE can be reported per destination.

Figures 3 (a) and 3 (b) illustrate some embodiments for destination selection when multiple destinations have both logical channels and sidelink CSI reporting MAC CE has the same priority. The logical channel has the same priority with the sidelink CSI reporting MAC CE means the priority value of the logical channel is "1" .

In Figure 3 (a) , there are two destinations, destination 1 has sidelink CSI reporting MAC CE and LCH, the priority value of the sidelink CSI reporting MAC CE and the priority value of the LCH are both "1" , and destination 2 has LCH with a priority value of "1" .

In this solution, if multiple destinations have both logical channels, select destination which contains both MAC CE and logical channel, if highest priority of logical channel in this destination has same priority as the MAC CE.

This means that destination 1 has both LCH with the priority of "1" and MAC CE with the priority of "1" , and destination 1 has LCH with the priority of "1" , then select destination has both LCH and MAC CE in this case is better. Therefore, destination 1 is selected.

In Figure 3 (b) , there are two destinations, destination 1 has sidelink CSI reporting MAC CE and LCH, the priority value of the MAC CE and the priority value of the LCH are both "1" , and the latency requirement for destination 1 is x ₁ ms, which is determined based on the latency bound of the MAC CE and the PDB of the LCH. Destination 2 has LCH with a priority value of "1" , and the latency bound for destination 2 is y ₂ ms.

In this solution, if multiple destinations have both logical channels and MAC CE has the same priority, select destination which has lower latency bound or PDB value. That is, in Figure 3 (b) , if x ₁ < y ₂, destination 1 will be selected during destination selection in LCP. If x ₁ ≥ y ₂, destination 2 will be selected during destination selection in LCP.

The above technical solutions relate to the destination among the UEs. When the Tx UE also has uplink transmission, according to TS 38.321 SL prioritization procedure, the transmission of the MAC PDU is prioritized over uplink transmissions of the MAC entity or the other MAC entity if the following conditions are met:

i. if the MAC entity is not able to perform this sidelink transmission simultaneously with all uplink transmissions at the time of the transmission, and

ii. if uplink transmission is neither prioritized as specified in clause 5.4.2.2 nor prioritized by upper layer according to TS [24.386] ; and

iii. if the value of the highest priority of logical channel (s) and a MAC CE in the MAC PDU is lower than sl-PrioritizationThres if sl-PrioritizationThres is configured.

Currently, the sidelink CSI reporting MAC CE handling during UL/SL prioritization principle is as following:

i. Step 1. UL data priority compared with UL_threshold

ii. Step 2. If UL is not prioritized in step 1, SL data priority compared with SL_threshold

iii. Step 3. If SL is not prioritized in step 2, transmit UL

If sidelink CSI reporting MAC CE also follows the above rule, then sidelink CSI will always been prioritized in step 2, even when sidelink CSI is not that important. Then UL transmission will be unnecessarily blocked in this case.

In order to avoid the unnecessary blocking problem in the prior art, the subject disclosure proposes to take the latency requirement into consideration during the UL/SL prioritization procedure.

Figure 4 illustrates an embodiment of destination selection during the UL/SL prioritization procedure. In Figure 4, the Tx UE has sidelink transmission to destination 1 and the uplink transmission to the BS.

In this solution, the destination having sidelink CSI reporting MAC CE is only considered to be prioritized when its latency requirement, i.e. latency bound, is lower than a threshold. The threshold is configured by the BS, pre-configured, or defined in the specification.

When the latency requirement, i.e. latency bound, of sidelink CSI reporting MAC CE is lower than the threshold, which means sidelink CSI is urgent, sidelink CSI is considered in SL prioritization procedure. Otherwise, sidelink CSI is not considered during SL prioritization.

For example, in Figure 4, uplink transmission and sidelink transmission are collided for V2X UE. The SL transmission to destination 1 contains sidelink CSI reporting MAC CE, and the latency bound is x ₁ ms. A threshold "sl-PrioritizationPDBThres" is configured. In this case, when determine the highest priority of logical channels and MAC CE for this SL transmission, only those MAC CE whose x ₁ < "sl-PrioritizationPDBThres" is considered.

Figure 5 illustrates a method performed by a UE for sidelink communication according to a preferred embodiment of the subject disclosure. In step 501, a Tx UE selects the destination from multiple destinations having sidelink connections with the UE based on latency requirements of the multiple destinations, wherein the multiple destinations are to receive one or more MAC CEs and one or more logical channels from the UE, and in step 502, the Tx UE performs transmission to the selected destination. For example, in Figure 2 (a) , the Tx UE selects a destination from destination 1, destination 2, and destination 3, then perform sidelink transmission on to the selected destination.

In one embodiment, the Tx UE selects a destination having a first MAC CE with highest priority as the destination, unless the first MAC CE has a first latency requirement equal to or lower than a second latency requirement of a logical channel with highest priority, among the one or more logical channels. For example, in Figure 2 (a) , the Tx UE selects destination 1 unless the latency requirement (x ₁) of destination 1 is equal to or lower than the latency requirement (y ₂) of destination 2, or the Tx UE selects destination 2 when the latency requirement (x ₁) of destination 1 is equal to or lower than the latency requirement (y ₂) of destination 2.

In another embodiment, the Tx UE selects a destination having a logical channel with highest priority among the one or more logical channels and with a latency requirement higher than a threshold. For example, in Figure 2 (a) , if y ₂ is lower than a configured threshold, then destination 2, which having the logical channel with the highest priority, will be selected.

In still another embodiment, the Tx UE selects a destination having a MAC CE with a latency requirement higher than a threshold. For example, in Figure 2 (b) , destination 2 includes sidelink CSI reporting MAC CE, the latency bound is x ₂. Destination 3 includes logical channel with a priority 5, and is not considered in this embodiment.

In yet another embodiment, for a fifth destination having both a fifth MAC CE and a fifth logical channel and a sixth destination having no MAC CE and a sixth logical channel, the fifth destination is selected if the fifth MAC CE and the fifth logical channel have the same level of latency requirement, and have the same priority level. For example, in Figure 3 (a) , there are destination 1, which having both MAC CE and logical channel, and destination 2, which only has a logical channel, and destination 1 is selected.

In yet another embodiment, if the one or more MAC CE and the one or more logical channel have the same level of priority, selecting a destination having a MAC CE or a logical channel with highest latency requirement. For example, in Figure 3 (b) , destination 1 having both MAC CE and logical channel has the latency requirement x ₁, and destination 2 only having a logical channel has the latency requirement y ₂. If x ₁ < y ₂, destination 1 will be selected during destination selection in LCP. If x ₁ ≥ y ₂, destination 2 will be selected during destination selection in LCP.

The latency requirement for a MAC CE corresponds to a latency bound value, and the latency requirement for a logical channel corresponds to the PDB.

Figure 6 illustrates a method performed by a UE for sidelink communication according to a preferred embodiment of the subject disclosure. In step 601, the Tx UE selects the prioritized transmission from an uplink transmission to a BS and one or multiple sidelink transmissions from the UE based on latency requirements of the uplink transmission and one or multiple sidelink transmissions. In step 602, the Tx UE performs the prioritized transmission. For example, in Figure 4, the Tx UE selects the prioritized transmission from an uplink transmission to a BS and one sidelink transmission.

In one embodiment, the Tx UE selects the uplink transmission as the prioritized transmission if the latency requirements of each of the sidelink transmission (s) are equal to or lower than a threshold. Alternatively, the Tx UE selects a first sidelink transmission from one or multiple sidelink transmissions as the prioritized transmission if the first destination has a MAC CE with a first latency requirement higher than a threshold.

For example, in Figure 4, the Tx UE selects the uplink transmission when the latency bound, x ₁ of sidelink CSI reporting MAC CE is equal to lower than the threshold, which means sidelink CSI is urgent, and the sidelink CSI is considered in SL prioritization procedure. Otherwise, sidelink CSI is not considered during SL prioritization.

Figure 7 illustrates a block diagram of a UE according to the embodiments of the subject disclosure. The UE may include a receiving circuitry, a processor, and a transmitting circuitry. In one embodiment, the UE may include a non-transitory computer-readable medium having stored thereon computer-executable instructions; a receiving circuitry; a transmitting circuitry; and a processor coupled to the non-transitory computer-readable medium, the receiving circuitry and the transmitting circuitry. The computer executable instructions can be programmed to implement a method (e.g. the methods in Figures 5 and 6) with the receiving circuitry, the transmitting circuitry and the processor. That is, the processor may selects the destination from multiple destinations having sidelink connections with the UE based on latency requirements of the multiple destinations, wherein the multiple destinations are to receive one or more MAC CEs and one or more logical channels from the UE, and the transmitting circuitry may performs, on the UE, transmission to the selected destination.

The method of the present disclosure can be implemented on a programmed processor. However, the controllers, flowcharts, and modules may also be implemented on a general purpose or special purpose computer, a programmed microprocessor or microcontroller and peripheral integrated circuit elements, an integrated circuit, a hardware electronic or logic circuit such as a discrete element circuit, a programmable logic device, or the like. In general, any device that has a finite state machine capable of implementing the flowcharts shown in the figures may be used to implement the processing functions of the present disclosure.

While the present disclosure has been described with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. For example, various components of the embodiments may be interchanged, added, or substituted in the other embodiments. Also, all of the elements shown in each figure are not necessary for operation of the disclosed embodiments. For example, one skilled in the art of the disclosed embodiments would be capable of making and using the teachings of the present disclosure by simply employing the elements of the independent claims. Accordingly, the embodiments of the present disclosure as set forth herein are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the present disclosure.

In this disclosure, relational terms such as "first, " "second, " and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms "comprises, " "comprising, " or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "a, " "an, " or the like does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element. Also, the term "another" is defined as at least a second or more. The terms "including, " "having, " and the like, as used herein, are defined as "comprising. "

Claims

A method performed on a User Equipment (UE) for selecting a destination, comprising:

selecting the destination from multiple destinations having sidelink connections with the UE based on latency requirements of the multiple destinations, wherein the multiple destinations are to receive one or more Media Access Control Control Elements (MAC CEs) and one or more logical channels from the UE; and

performing, on the UE, transmission to the selected destination.
The method of Claim 1, wherein selecting the destination comprises:

selecting a first destination having a first MAC CE with highest priority as the destination, unless the first MAC CE has a first latency requirement equal to or lower than a second latency requirement of a logical channel with highest priority, among the one or more logical channels.
The method of Claim 2, wherein selecting the destination further comprises:

selecting a second destination having the logical channel with highest priority as the destination if the first latency requirement of the first MAC CE is equal to or lower than the second latency requirement of the logical channel.
The method of Claim 1, wherein selecting the destination comprises:

selecting a third destination having a logical channel with highest priority among the one or more logical channels and with a third latency requirement higher than a first threshold.
The method of Claim 1, wherein selecting the destination comprises:

selecting a fourth destination having a MAC CE with a fourth latency requirement higher than a second threshold.
The method of Claim 1, wherein for a fifth destination having both a fifth MAC CE and a fifth logical channel and a sixth destination having no MAC CE and a sixth logical channel, the fifth destination is selected if the fifth MAC CE and the fifth logical channel have the same level of latency requirement, and have the same priority level.
The method of Claim 1, further comprising:

if the one or more MAC CE and the one or more logical channel have the same level of priority, selecting a seventh destination having a seventh MAC CE or a seventh logical channel with highest latency requirement.
The method of Claim 1, wherein the latency requirement corresponds to a latency bound value of a MAC CE or a Packet Delay Budget (PDB) of a logical channel.
A method performed on a User Equipment (UE) for selecting a prioritized transmission, comprising:

selecting the prioritized transmission from a uplink transmission to a Base Station (BS) and one or multiple sidelink transmissions from the UE based on latency requirements of the uplink transmission and one or multiple sidelink transmissions; and

performing the prioritized transmission.
The method of Claim 9, further comprising:

selecting the uplink transmission as the prioritized transmission if the latency requirements of each of the sidelink transmission (s) are equal to or lower than a threshold.
The method of Claim 9, further comprising:

selecting a first sidelink transmission from one or multiple sidelink transmissions as the prioritized transmission if the first destination has a Media Access Control Control Element (MAC CE) with a first latency requirement higher than a threshold.
An apparatus, comprising:

a non-transitory computer-readable medium having stored thereon computer-executable instructions;

a receiving circuitry;

a transmitting circuitry; and

a processor coupled to the non-transitory computer-readable medium, the receiving circuitry and the transmitting circuitry,

wherein the computer-executable instructions cause the processor to implement the method of any of Claims 1-11.