CN116325567A - Efficient transmission of system information - Google Patents

Abstract

Various methods of transmitting minimum system information from a base station in an Orthogonal Frequency Division Multiplexing (OFDM) transmission system are proposed. The Master Information Block (MIB) is multiplexed with the Remaining Minimum System Information (RMSI) information, including a Physical Downlink Control Channel (PDCCH) and a Physical Downlink Shared Channel (PDSCH), in the form of a synchronization signal/physical broadcast channel (SS/PBCH) block, and transmits the RMSI information within the frequency span of the control resource set #0 (core # 0). The SS/PBCH and RMSI information occupy the same occupancy in time, but may include a different number of OFDM symbols. The OFDM system may operate in licensed and unlicensed spectrum.

Description

Efficient transmission of system information

Technical Field

The following disclosure relates to transmission of system information in a wireless communication system, and more particularly, to transmission of minimum system information in high frequency operation.

Background

Wireless communication systems, such as third generation (3G) mobile phone standards and technologies, are well known, and the third generation partnership project (3 GPP) has developed such 3G standards and technologies, and generally, third generation wireless communications have been developed to the extent that macrocell mobile phone communications are supported, communication systems and networks have been developed toward broadband and mobile systems.

In a cellular wireless communication system, a User Equipment (UE) is connected to a radio access network (Radio Access Network, RAN) by a wireless link. The RAN includes a set of base stations (base stations) providing radio links to UEs located in cells covered by the base stations and includes an interface to a Core Network (CN) having a function of controlling the overall Network. It is understood that the RAN and CN each perform a corresponding function with respect to the entire network. For convenience, the term "cellular network" will be used to represent a combination of RAN and CN, but it will be understood that the term is also used to represent various systems for performing the disclosed functions.

The third generation partnership project has evolved a so-called Long Term Evolution (LTE) system, an evolved universal mobile telecommunications system regional radio access network (E-UTRAN), for a mobile access network of one or more macro cells supported by base stations called enodebs or enbs (evolved nodebs). Recently, LTE has evolved further to so-called 5G or New Radio (NR) systems, where one or more cells are supported by a base station called a gNB. When NR is proposed, an orthogonal frequency division multiplexing (Orthogonal Frequency Division Multiplexed, OFDM) physical transport format is utilized.

The NR protocol is intended to provide the option of operating in the unlicensed radio frequency range (referred to as NR-U). While operating in the unlicensed radio band, the gNB and UE must compete for physical medium/resource access with other devices. For example, wi-Fi, NR-U, and LAA may use the same physical resources.

The trend in wireless communication is toward services that provide lower latency and higher reliability. For example, NR is aimed at supporting Ultra-reliable and low-latency communication (URLLC), whereas large-scale machinesThe purpose of type communication (mctc) is to provide low latency and high reliability for small data packets (typically 32 bytes). A user plane delay of 1ms has been proposed with a reliability of 99.99999% and in terms of the physical layer, a packet loss ratio of 10 has been proposed ^-5 Or 10 ^-6 Is provided.

The mctc service aims to support a large number of devices with an energy efficient communication channel over a long lifetime. In this case, data transmission with each device is sporadic and infrequently performed. For example, a cell may support thousands of devices.

In NR, the UE needs to decode minimum system information (minimum system information, MSI) broadcast by the base station to initiate any form of communication. MSI is broadcast on a Physical Broadcast Channel (PBCH) in the form of a master information block (master information block, MIB) carrying the basic system information, and the remaining system information (remaining system information, RMSI), as system information block type 1 (SIB 1). The set of control resources (control resource set, CORESET) configured by MIB, referred to as CORESET #0, is used to transmit Downlink Control Information (DCI) indicating the resources scheduled for the Physical Downlink Shared Channel (PDSCH) carrying SIB1.

To initiate communication, the UE decodes the MIB as part of a cell search procedure, which enables the UE to obtain time and frequency synchronization consistent with the base station and detect a physical layer cell Identifier (ID). The UE receives Synchronization Signals (SS) in the form of primary synchronization signals (primary synchronisation signal, PSS) and secondary synchronization signals (secondary synchronization signal, SSS), which are continuous signals, together defining a Physical Broadcast Channel (PBCH) and forming SS/PBCH blocks. By decoding the PBCH, the UE can decode the MIB to complete the configuration and receive and initiate Downlink (DL) and Uplink (UL) communications, respectively.

The following disclosure relates to various improvements to cellular wireless communication systems.

Disclosure of Invention

The present invention is defined by the claims, wherein a method of transmitting minimum system information from a base station in an Orthogonal Frequency Division Multiplexing (OFDM) transmission system is provided, characterized in that the method comprises the steps of: transmitting a Master Information Block (MIB) in the form of a synchronization signal/physical broadcast channel (SS/PBCH) block and transmitting Remaining Minimum System Information (RMSI) information on at least one other channel, wherein the transmitting step includes: multiplexing the SS/PBCH with the RMSI information; and transmitting the RMSI information within a frequency span of control resource set #0 (CORESET # 0).

The RMSI information includes at least system information block 1 (SIB 1) RMSI PDCCH and/or a PDSCH channel.

The SS/PBCH block is transmitted on n at least one OFDM symbol and the RMSI information is transmitted on m at least one OFDM symbol, where n is a multiple of m.

The SS/PBCH block is transmitted on n at least one OFDM symbol and the RMSI information is transmitted on m at least one OFDM symbol, where n is equal to m.

The multiplexing step includes multiplexing over time.

The OFDM system operates in licensed and unlicensed spectrum.

The subcarrier spacing (SCS) of the channel carrying the SS/PBCH block is a multiple of the SCS of the channel carrying the RMSI information such that the SS/PBCH block and the RMSI information occupy the same period of time.

The start of the SS/PBCH block and the start of the RMSI information are aligned.

The SS/PBCH block and the RMSI information are equal in time and terminate simultaneously.

The Physical Downlink Control Channel (PDCCH) and the Physical Downlink Shared Channel (PDSCH) are transmitted serially or in parallel.

And provides a base station configured to perform the methods described herein.

And provides a UE configured to decode MIB transmitted according to the methods described herein.

Drawings

Further details, aspects and embodiments of the invention are described below, by way of example only, with reference to the accompanying drawings. For simplicity and clarity, elements in the figures have been shown and are not necessarily drawn to scale. For ease of understanding, the same reference numerals are included in the various figures.

Fig. 1 illustrates selected elements of a cellular wireless communication network.

Detailed Description

Those skilled in the art will recognize and appreciate that the specific details of the examples described are merely illustrative of some embodiments and that the teachings set forth herein are applicable in a variety of alternative configurations.

Fig. 1 shows a schematic diagram of three base stations (e.g., enbs or gnbs, depending on the particular cellular network standard and terminology) forming a cellular network. Typically, each base station will be deployed by a cellular network operator to provide geographic coverage for UEs in the area. These base stations form a radio area network (Radio Area Network, RAN). Each base station provides radio signal coverage for UEs in its area or cell. These base stations are interconnected by an X2 interface and connected to the core network by an S1 interface. As will be appreciated, only a few basic details are shown here to facilitate exemplary explanation of the critical features of a cellular network. A PC5 interface is provided between multiple UEs for side-chain (SL) communication. The interface and component names associated with fig. 1 are used as examples only, and different systems operating on the same principles may use different nomenclature.

Each base station includes hardware and software for implementing RAN functions including functions to communicate with the core network and other base stations, the piggybacking of control and data signals between the core network and the UEs, and maintaining or maintaining wireless communications of the UEs associated with each base station. The core network includes hardware and software for implementing network functions such as management and control of the overall network, and routing of calls and data.

The standard (section 7.4.3.1 of 3GPP technical standard 38.211) defines the time-frequency structure of SS/PBCH blocks. In the time domain, one SS/PBCH block consists of 4 OFDM symbols, numbered in ascending order from 0 to 3 within the SS/PBCH block.

In the frequency domain, one SS/PBCH block consists of 240 consecutive subcarriers (20 resource blocks each including 12 subcarriers), and the subcarriers are numbered in ascending order from 0 to 239 within the SS/PBCH block.

The MIB carries a system frame number (system frame number, SFN), a common subcarrier spacing (SCS) (common SCS is SCS for decoding SIB 1), demodulation reference symbols (DMRS), and information necessary for the UE to decode SIB1. It also provides information whether the current cell is barred.

The base station transmits a Physical Downlink Control Channel (PDCCH) on a pre-configured region of the time-frequency grid, known as the control resource set (CORESET). The search space provides a configuration associated with a given CORESET and specifies the symbols and Physical Resource Blocks (PRBs) that the UE uses to attempt PDCCH decoding. The 5GNR defines a common and UE-specific search space.

The common search space of type 0 is used for PDCCH transmission, which allocates resources for SIB1. The search space is indicated by using the MIB, and is carried on the PBCH, or can be indicated by using a PDCCH-ConfigCommon structure. The common search space of type 0 maps to CORESET (CORESET # 0) identified as 0. The PDCCH for SIB1 resource allocation is transmitted using a Cyclic Redundancy Check (CRC) encoded with a System Information (SI) Radio Network Temporary Identifier (RNTI), which is a fixed parameter known to all devices. This PDCCH is transmitted using DCI format 1_0.

More precisely, the PBCH embedded in the SS/PBCH block carries the following information elements (3 GPP technical standard 38.331 and 3GPP technical standard 38.213):

·subCarrierSpacingCommon

·PDCCH-ConfigSIB1-controlResourceSetZero

·PDCCH-ConfigSIB1-searchSpaceZero

the subclrierspacengcommon provides an SCS for transmitting PDCCHs carrying SIB1 assignments, which may be different from the SCS for transmitting SS/PBCH blocks. The control resource zero information element provides a row index that uses a 4-bit indication in the CORESET configuration table. Each combination of (scs_ss/PBCH, scs_pdcch) has a different CORESET configuration table. Once the UE decodes the SS/PBCH block and finds the subclrierspace command, it can use the row index to point to the relevant CORESET configuration table to find the SCS combination for the SS/PBCH block and PDCCH for SIB1. For each of its component rows, the CORESET configuration table provides the number of PRBs, the number of symbols, the resource block offset relative to the SS/PBCH block, and the multiplexing mode of the SS/PBCH block and CORESET. The 3GPP technical standard 38.213 contains more detailed information.

searchSpaceZero provides an index (4-bit indication) to a particular row in the search space configuration table. The 5G NR formulates a plurality of search space configuration tables, each of which is applicable to a given frequency range and multiplexing mode of a given SS/PBCH block and CORESET. The search space configuration table provides the location of the search space in terms of frames, slots, and the number of sets of search spaces per slot so that the UE can determine the correct search space for PDCCH decoding attempts. The 3GPP technical standard 38.213 contains more detailed information.

The PDCCH scheduling SIB1 uses DCI format 1_0, which provides the resource allocation and other parameters needed to decode the PDSCH carrying SIB1. DCI format 1_0 carries one field, i.e., a Time Domain Resource Assignment (TDRA). The TDRA indication from PDCCH and the dmrs-type a-Position indication from MIB help select the appropriate row from the TDRA table. For PDSCH that will carry SIB1 information, each row in this table provides information using the slot offset, the time resource of the starting symbol, and the length of the scheduled resource.

SIB1 provides base station selection information, system information scheduling information, serving base station configuration and other emergency service related information elements. The service base station configuration comprises downlink configuration public information and uplink configuration public information. The DL configuration common information in turn provides information about DL frequencies, DL bandwidth parts (BWP), and the configuration of paging and broadcast control channels. The BWP configuration includes a common configuration of the PDCCH and the PDSCH. UL configuration common information provides UL frequency information, initial UL BWP. BWP UL provides information about RACH, PUCCH and PUSCH configurations.

For example, standards such as 3GPP specify two frequency ranges, frequency ranges FR1 and FR2.FR1 originally goes up to 6GHz but later extends to 7.125GHz. FR2 is originally specified as from 24.25GHz to 52.6GHz. Release 15 and 16 operations of the 5G New Radio (NR) are formulated for these frequency ranges. Version 17 focuses on extending FR2 operation up to 71GHz. These extensions may reach 100GHz or even higher, as the wide availability of spectrum and advances in antenna/RF at such high carrier frequencies may allow for efficient communication at these frequencies, which has previously been considered very difficult. Systems operating at such high carrier frequencies need to resort to beam-based transmissions. These systems need to transmit SS/PBCH blocks in a broadcast manner in each beam direction with a given period, and the remaining minimum system information SIB1 or RMSI (scheduling command in PDCCH form and information in PDSCH). For FR2, the base station can use up to 64 beams. This results in considerable overhead and imposes certain scheduling constraints due to the forced adoption of beam scanning.

For beam-based operation, the base station would transmit the SS/PBCH block, PDCCH in CORESET0, and the associated PDSCH carrying SIB1 in each beam direction. Due to the large number of active beams, the user density may be unevenly distributed, so that the transmissions of PDCCH and PDSCH of SS/PBCH block and SIB1 need to activate each beam within the shortest duration allowed for such transmissions, resulting in waste of time-frequency resources and very low system efficiency. This problem will become more serious for the new combination of SS/PBCH blocks and SCS of PDCCH scheduling SIB1. This problem is exacerbated in the case of unlicensed spectrum due to channel uncertainty (loss of channel ownership due to the base station possibly being in the gaps between these transmissions or due to the need to perform channel access procedures between these transmissions).

The transmission of minimum system information describes the method of multiplexing between SS/PBCH blocks and CORESET 0. Furthermore, in order to optimize the transmission of SS/PBCH blocks and SIB1 and the resource allocation to PDSCH, the overhead required to transmit such control information may be reduced when combined with the described multiplexing mode. The gap minimization scheme described herein provides protection against loss of channel ownership. This makes these schemes more attractive for operation on shared carriers. Furthermore, the described scheme circumvents the requirement that channel access needs to be ensured after a transmission gap. Thus, the methods described herein are applicable to unlicensed spectrum.

The CORESET configuration and PDSCH resource scheduling option ensures that transmissions of PDCCH and scheduled PDSCH in CORESET0 are limited to the same time period as the SS/PBCH block. This achieves minimum activation time requirements in each single beam and minimizes beam switching that results in delays and transitions. This uses a relatively large span of frequency resources because different pieces of minimum system information are multiplexed over frequency. This may be fully acceptable at the higher carrier frequencies where large bandwidths are typically available. This applies to operation on unlicensed shared carriers, as it reduces the need for channel sensing in the different beams, and also reduces the likelihood of loss of channel ownership to other devices during SS/PBCH block and RMSI transmissions. Each piece of system information is transmitted in the form of an indivisible cluster.

The system transmits minimum system information of a Master Information Block (MIB) and Remaining Minimum System Information (RMSI), also called SIB1, in the SS/PBCH block in the shortest possible occupation time. The SS/PBCH block uses a fixed structure consisting of 4 OFDM symbols and transmits RMSI (scheduling PDCCH and PDSCH) in a manner completely overlapping in time with the SS/PBCH block, although they employ different subcarrier spacing (SCS). This method uses a combination of SCS, where the SCS of SS/PBCH block may be equal to or 2 or 4 times the SCS of PDCCH scheduling RMSI. For these SCS combinations, the exact CORESET0, search space type 0 layout (PDCCH carrying scheduled RMSI), and default data allocation items for PDSCH are configured. These proposed configurations enable multiplexing of SS/PBCH blocks with RMSI (PDCCH plus PDSCH) over frequency, thus using minimal time occupation for transmission of minimum system information, without any restrictions on the SCS used. This results in a significant reduction in overhead for system information transmission. Three transmission units (SS/PBCH block, PDCCH and PDSCH of RMSI) are always transmitted in a single cluster, so that the influence of channel uncertainty is reduced to the greatest extent.

RMSI is multiplexed into the same time occupation as the SS/PBCH blocks to avoid that RMSI extends beyond the SS/PBCH blocks. This in turn reduces the overhead per beam direction and creates decoding advantages due to the increased amount of RMSI data transmitted in the PDSCH.

Each base station transmits one SS/PBCH block, allowing each UE to synchronize, and then transmits SIB1 (RMSI) scheduled through search space set0 on CORESET # 0. This provides the UE with minimum system information required to decode Downlink (DL) data or initial Uplink (UL) data transmission. This forces the base station to transmit SS/PBCH blocks in all beam directions, PDCCH transmitted on CORESET #0 that schedules SIB1, and SIB1 as part of the base cell coverage, enabling the UE to contact the base station based on this minimum system information.

In order to minimize the overhead of MIB/SIB1 transmission and avoid channel uncertainty on the shared carrier, SS/PBCH blocks, PDCCH and SIB1 (RMSI) need to be multiplexed in as few symbol numbers as possible. An SS/PBCH block is a set of fixed signaling that is transmitted over 4 OFDM Symbols (OS) with a subcarrier spacing (SCS) of the SS/PBCH block.

Since SS/PBCH block and SIB1 (RMSI) use different subcarrier spacing (SCS), a given multiplexing mode may not necessarily be applicable to all combinations of SS/PBCH block and SCS of PDCCH scheduling RMSI.

This method enables transmission and multiplexing of SIB1 when SCS used by SS/PBCH block is 4 times larger than SCS of PDCCH scheduling PDSCH carrying SIB1. The 4 symbols carrying SS/PBCH blocks correspond to using only one symbol in the parameter set of PDCCH of SIB1. This setup applies to SCS of { SS/PBCH block, PDCCH } including {240,60}, {480,120}, {960,240}, {1920,480} khz and other potential SCS combinations with similar proportions. The proposal for multiplexing of CORESET0 with SS/PBCH blocks and the associated PDSCH carrying SIB1 (RMSI) is as follows. The SS/PBCH block is transmitted on 4 OFDM symbols n, n+1, n+2, and n+3. This corresponds to one OFDM symbol "m" in the parameter set used for PDCCH and SIB1PDSCH in CORESET 0.

TABLE 1

CORESET0 is configured on one OFDM symbol, which spans the same period of time as 4 OFDM symbols of an SS/PBCH block. In addition, the PDCCH transmitted in CORESET0 schedules PDSCH carrying SIB1 (RMSI) in a period of 1 OFDM symbol, where one OFDM symbol is also aligned with CORESET0 and SS/PBCH blocks.

The CORESET0 configuration, the search space type 0 configuration, and the default PDSCH allocation table, the so-called Time Domain Resource Assignment (TDRA) table, need to be updated so that the CORESET0 configuration can support a single symbol configuration with a sufficient number of PRBs. To this end, CORESET #0 configuration may be allowed to occupy 192 or more PRBs. The associated search space configuration table should add entries such that the index value of the first symbol is aligned with the first OFDM symbol of the SS/PBCH block. The default TDRA table for PDSCH resource allocation supports scheduling of PDSCH such that the starting OFDM symbol (denoted S in the TDRA table) is aligned with the starting position of CORESET0 and the length of the allocated resource (denoted L in the TDRA table) may be configured to be 1 OFDM symbol. Since PDSCH is transmitted in the same slot as PDCCH in CORESET0, the slot offset of this term should be set to zero.

The default active DL bandwidth portion (BWP) is limited to the frequency span of CORESET 0. This means that the UE should not be scheduled outside the frequency resource span indicated to CORESET 0. The base station may then update the active DL BWP by SIB1 signaling and ask the base station to update the active DL BWP to a frequency span greater than CORESET 0. To overcome this limitation, the system is configured to have CORESET0 over one frequency span and the PDCCH is transmitted using a portion of the configured CORESET0 PRBs. This allows the PDSCH carrying RMSI to be scheduled on another portion of the frequency resource span indicated to CORESET0 by transmitting RMSI data on the PDSCH scheduled in the resources configured for CORESET 0. For illustration only, table 1 uses PDCCH transmitted in CORESET0 that utilizes 50% of the available CORESET0 resource frequency span, with the remaining 50% of the available CORESET0 resource frequency span being used for RMSI PDSCH. One allowed scheme is that the entire frequency span of CORESET0 may be indicated in the PDCCH as a resource of PDSCH and the UE rate-matches it using the decoded PDCCH. Another scheme is to precisely allocate the frequency location of PDSCH within CORESET0 using the frequency allocation field in PDCCH.

The above examples show SS/PBCH blocks, CORESET0 and RMSI PDSCH without any frequency gaps. But this is by way of example only, it should be understood that the actual configuration/scheduling may include frequency Slots (PRBs) located between blocks. Although SCS is different, these blocks span the same time period, thereby achieving a minimum duration for transmitting SS/PBCH blocks and RMSI. Similarly, the actual frequency resource span of CORESET0, RMSI PDSCH may be larger or smaller than the SS/PBCH block or split around the SS/PBCH block. This may be done easily by a resource block offset indication as part of the CORESET0 configuration.

Also, as another scheme, table 2 below shows an example in which SCS used for RMSI transmission with one SS/PBCH block is twice as large as SCS of PDCCH used to schedule PDSCH carrying SIB1 (RMSI). The 4 OFDM symbols carrying SS/PBCH blocks correspond to two OFDM symbols in the parameter set of PDCCH of SIB1. This setup applies to SCS of { SS/PBCH block, PDCCH } including {120,60}, {240,120}, {480,240}, {960,480}, {1920,960} khz and other potential SCS combinations with this ratio.

Two OFDM symbols in the PDCCH parameter set (in CORESET 0) are used for both CORESET0 configuration and scheduling of RMSI PDSCH in a frequency multiplexed fashion with SS/PBCH blocks. This multiplexing is shown in table 2. The table shows SS/PBCH blocks spanning 4 OFDM symbols n, n+1, n+2 and n+3. Two equivalent OFDM symbols m and m+1 in the PDCCH parameter set are used to configure CORESET0 and allocate resources for RMSI PDSCH, RMSI PDSCH are scheduled by the PDCCH transmitted in CORESET 0.

TABLE 2

This may be achieved by a CORESET0 configuration supporting 2 OFDM symbols, which allows it to be aligned with the first symbol of the SS/PBCH block, and allows PDSCH time domain resources of 2 OFDM symbols to be allocated with the same starting symbol as CORESET0, which is aligned with the first OFDM symbol of the SS/PBCH block.

For an initial active DL BWP operation to be limited to the frequency resource range of the CORESET0 configuration, RMSI PDSCH must be limited in this resource. Once the base station updates the active DL BWP, RMSI PDSCH may be allocated within the DL BWP, which is not necessarily limited to the frequency resource span of the CORESET0 configuration. If the initial active DL BWP is limited to the frequency resource span of the CORESET0 configuration, the PDCCH of schedule RMSI PDSCH may be transmitted on a portion of the CORESET0 configured resources, while the remaining portion of the active DL BWP may be used to schedule RMSI PDSCH, as shown in table 2.

In this example, a scheduling command (PDCCH) and a data-bearing MSI (PDSCH) are frequency multiplexed with SS/PBCH blocks while being time domain multiplexed with each other. The 4 OFDM symbols of the SS/PBCH block correspond to two OFDM symbols in the PDCCH parameter set. Two OFDM symbols in the PDCCH parameter set (in CORESET 0) are equally divided in time, with 1 OFDM symbol allocated for CORESET0 configuration and RMSI PDSCH scheduled on the second OFDM symbol. Thus, this approach has CORESET0 configuration and RMSI PDSCH scheduling in a TDMA fashion with respect to each other. CORESET0 and SIB1 (RMSI) PDSCH together are frequency domain multiplexed with the SS/PBCH blocks.

TABLE 3 Table 3

Table 3 shows the CORESET0 configuration and RMSI PDSCH schedule. The SS/PBCH block indicates a CORESET0 configuration of 1 OFDM symbol, and PDCCH transmitted within CORESET0 schedules PDSCH (carrying RMSI) with its starting symbol aligned with the last 2 OFDM symbols of the SS/PBCH block and 1 OFDM symbol in length. { SS/PBCH block, PDCCH } SCS is COESET configuration { x, x/2} KHz COESET 0 configuration supporting 1 OFDM symbol, search space type 0 needs to define a configuration with entries to align with the first OFDM symbol of SS/PBCH block, default TDRA table has one entry, wherein PDSCH length is 1 OFDM symbol, starting from symbol m+1, to align with the last 2 OFDM symbols of SS/PBCH block. Thus, CORESET0 and PDSCH are multiplexed in time, and the frequency resource span scheduled for PDSCH may be limited to the frequency resource span of CORESET0 configuration and within the initial active DL BWP.

CORESET0 may be configured on a single OFDM symbol aligned with the first two OFDM symbols of the SS/PBCH block, with SIB1 (RMSI) PDSCH allocated to time resources spanning two OFDM symbols aligned with the 4 OFDM symbols of the SS/PBCH block, as shown in table 4. Thus, CORESET0 and PDSCH may be frequency multiplexed in the first OFDM symbol. This may be used if the PDSCH of a single symbol is deemed insufficient to carry SIB1 data. In this case, additional resources may be allocated for PDSCH to provide better protection. In this example, PDCCH and PDSCH for RMSI are frequency multiplexed with SS/PBCH blocks, but time and frequency multiplexed with each other.

For an initial active DL BWP operation to be limited to the frequency resource range of the CORESET0 configuration, RMSI PDSCH must be limited to this same resource. The PDCCH is transmitted on a portion of the CORESET0 configured frequency span resources, with the remainder of the CORESET0 configured frequency resource span available for transmission of SIB1 PDSCH.

TABLE 4 Table 4

The SS/PBCH block and PDCCH on CORESET0, which schedules PDSCH carrying RMSI with the same SCS, are shown in table 5. Four OFDM symbols in the PDCCH parameter set (in CORESET 0) are split such that 1 OFDM symbol is used for CORESET0 configuration and 3 OFDM symbols are allocated to RMSI PDSCH. SIB1 may contain proportionally more information than is carried in PDCCH transmitted in CORESET0, which provides proportionally more RMSI PDSCH resources. To employ this multiplexing mode, the default time domain resource allocation in the TDRA table requires the addition of a new entry to allow PDSCH to be scheduled over a length of 3 OFDM symbols with the starting symbol aligned with the 2 nd OFDM symbol n+1 of the SS/PBCH block.

TABLE 5

In the case where CORESET0 and PDSCH are multiplexed in time, the frequency resource span scheduled for PDSCH may be limited to the frequency resource span configured for CORESET0 and within the initial active DL BWP. This can be used in case the activated DL BWP is limited to the frequency resource range of CORESET 0.

A method is illustrated in table 6, where four OFDM symbols in the PDCCH parameter set (in CORESET 0) are split such that 1 OFDM symbol is used for CORESET0 configuration and all 4 OFDM symbols aligned with the SS/PBCH block are allocated to RMSI PDSCH. This provides more resource allocation for SIB1 (RMSI) PDSCH than the above example, and may enable faster transmission of minimum system information. Table 5 shows a proposed design that includes a CORESET0 configuration of 1 OFDM symbol and 4 OFDM symbols for scheduling of RMSI PDSCH.

TABLE 6

For active DL BWP limited by the CORESET0 configuration, the PDCCH is transmitted on a portion of the CORESET0 frequency resource span in the first OFDM symbol, with the remaining frequency resource span of DL BWP on the first symbol and the next 3 symbols for SIB1 (RMSI) PDSCH transmission.

Although not shown in detail, any device or means forming part of the network may comprise at least a processor, a memory unit and a communication interface, wherein the processor unit, the memory unit and the communication interface are configured to perform the method of any aspect of the invention. Further options and choices are described below.

The signal processing functions of embodiments of the present invention, particularly the gNB and the UE, may be implemented using computing systems or architectures known to those skilled in the relevant art. Computing systems such as desktop, laptop or notebook computers, hand-held computing devices (PDAs, cell phones, palmtop computers, etc.), mainframes, servers, clients, or any other type of special or general purpose computing device as may be desired or appropriate for a given application or environment may be used. The computing system may include one or more processors, which may be implemented using a general-purpose or special-purpose processing engine (e.g., microprocessor, microcontroller, or other control module).

The computing system may also include a main memory, such as Random Access Memory (RAM) or other dynamic memory, for storing instructions and information to be executed by the processor. Such main memory may also be used for storing temporary variables and other intermediate information to be executed by the processor during execution of instructions. The computing system similarly may include a Read Only Memory (ROM) or other static storage device for storing static information and instructions for the processor.

The computing system may also include an information storage system, which may include, for example, a media drive and a removable storage interface. The media drive may include a drive or other mechanism to support fixed or removable storage media, such as a hard disk drive, floppy disk drive, magnetic tape drive, optical disk drive, compact Disk (CD) or Digital Video Drive (DVD) read or write drive (R or RW), or other removable or fixed media drive. Storage media may include, for example, hard disk, floppy disk, magnetic tape, optical disk, CD or DVD, or other fixed or removable medium that is read by and written to by media drives. The storage medium may include a computer-readable storage medium having particular computer software or data stored therein.

In alternative embodiments, the information storage system may include other similar components for allowing computer programs or other instructions or data to be loaded into the computing system. Such components may include, for example, removable storage units and interfaces such as program cartridges and cartridge interfaces, removable memory (e.g., flash memory or other removable memory modules) and memory slots, and other removable storage units and interfaces that allow software and data to be transferred from the removable storage unit to the computing system.

The computing system may also include a communication interface. Such a communication interface may be used to allow software and data to be transferred between the computing system and external devices. Examples of communication interfaces may include modems, network interfaces (such as ethernet or other NIC cards), communication ports (such as, for example, universal Serial Bus (USB) ports), PCMCIA slots and cards, and so forth. Software and data transferred via the communications interface are in the form of signals which may be electronic, electromagnetic and optical or other signals capable of being received by the communications interface medium.

In this document, the terms "computer program product," "computer-readable medium," "non-transitory computer-readable medium," and the like may be used generally to refer to tangible media, such as memory, storage devices, or storage units. These and other forms of computer-readable media may store one or more instructions for use by a processor, including a computer system, to cause the processor to perform specified operations. Such instructions, generally referred to as "computer program code" (which may be grouped in the form of computer programs or other groupings), when executed, enable the computing system to perform functions of embodiments of the present invention. Note that the code may directly cause the processor to perform the specified operations, be compiled to do so, and/or be combined with other software, hardware, and/or firmware elements (e.g., libraries for performing standard functions) to do so.

The non-transitory computer readable medium may include at least one of the group consisting of: hard disks, CD-ROMs, optical storage devices, magnetic storage devices, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, and flash memory. In embodiments where the elements are implemented using software, the software may be stored in a computer readable medium and loaded into a computing system using, for example, a removable storage drive. The control modules (in this example, software instructions or executable computer program code) when executed by a processor in a computer system cause the processor to perform the functions of the invention as described herein.

Furthermore, the inventive concept may be applied to any circuit for performing signal processing functions within a network element. It is further envisioned that a semiconductor manufacturer may utilize the inventive concepts in designing stand-alone devices such as Application Specific Integrated Circuits (ASICs) or microcontrollers of Digital Signal Processors (DSPs) and/or any other subsystem elements, for example.

It will be appreciated that the above description has described embodiments of the invention with reference to a single processing logic for clarity. However, the inventive concept may equally be implemented by a number of different functional units and processors to provide signal processing functionality. Thus, references to specific functional units are only to be seen as references to suitable means for providing the described functionality rather than indicative of a strict logical or physical structure or organization.

Aspects of the invention may be implemented in any suitable form including hardware, software, firmware or any combination of these. The invention may alternatively be implemented at least in part as computer software running on one or more data processors and/or digital signal processors or as a configurable module component such as an FPGA device.

Thus, the elements and components of an embodiment of the invention may be physically, functionally and logically implemented in any suitable way. Indeed the functionality may be implemented in a single unit, in a plurality of units or as part of other functional units. Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the invention is limited only by the appended claims. Furthermore, while certain features have been described in connection with specific embodiments, those skilled in the art will recognize that different features of the described embodiments may be combined in accordance with the invention. In the claims, the term "comprising" does not exclude the presence of other elements or steps.

Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented by e.g. a single unit or processor. Furthermore, although individual features may be included in different claims, these may possibly be advantageously combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. Moreover, the inclusion of a feature in one category of claims does not imply a limitation to this category but rather indicates that the feature is equally applicable to other claim categories as appropriate.

Furthermore, the order of features in the claims does not imply any specific order in which the features must be performed and in particular the order of individual steps in a method claim does not imply that the steps must be performed in that order. Rather, the steps may be performed in any suitable order. Furthermore, singular references do not exclude a plurality. Thus, references to "a," "an," "the first," "the second," etc. do not exclude a plurality.

Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the invention is limited only by the appended claims. Furthermore, while certain features have been described in connection with specific embodiments, those skilled in the art will recognize that different features of the described embodiments may be combined in accordance with the invention. In the claims, the term "comprising" does not exclude the presence of other elements.

Claims (13)

1. A method for transmitting minimum system information from a base station in an Orthogonal Frequency Division Multiplexing (OFDM) transmission system, the method comprising the steps of: transmitting a Master Information Block (MIB) in the form of a synchronization signal/physical broadcast channel (SS/PBCH) block and transmitting Remaining Minimum System Information (RMSI) information on at least one other channel, wherein the transmitting step includes: multiplexing the SS/PBCH with the RMSI information; and transmitting the RMSI information within a frequency span of control resource set #0 (CORESET # 0).

2. The method of claim 1, wherein the RMSI information includes at least a system information block 1 (SIB 1) RMSIPDCCH and/or a PDSCH channel.

3. The method of claim 1, wherein the SS/PBCH block is transmitted over n number of at least one OFDM symbol, and the RMSI information is transmitted over m number of at least one OFDM symbol, where n is a multiple of m.

4. The method of claim 1, wherein the SS/PBCH block is transmitted over n number of at least one OFDM symbol, and the RMSI information is transmitted over m number of at least one OFDM symbol, where n is equal to m.

5. A method according to any one of the preceding claims, wherein said multiplexing step comprises multiplexing over time.

6. A method according to any one of the preceding claims, wherein the OFDM system operates in licensed and unlicensed spectrum.

7. The method of claim 1, wherein a subcarrier spacing (SCS) of a channel carrying the SS/PBCH block is a multiple of an SCS of a channel carrying the RMSI information such that the SS/PBCH block and the RMSI information occupy a same time period.

8. The method of any of the preceding claims, wherein a start of the SS/PBCH block and a start of the RMSI information are aligned.

9. The method of claim 8, wherein the SS/PBCH block and the RMSI information are equal in length in time and terminate simultaneously.

10. The method of any of the preceding claims, wherein a Physical Downlink Control Channel (PDCCH) and a Physical Downlink Shared Channel (PDSCH) are transmitted serially.

11. The method according to any of claims 1 to 9, wherein PDCCH and PDSCH are transmitted in parallel.

12. A base station configured to perform the method of any of claims 1 to 11.

13. A User Equipment (UE) configured to decode the MIB transmitted as in any one of claims 1 to 11.

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