WO2024031528A1

WO2024031528A1 - Wireless communication devices and wireless communication methods for sbfd operation

Info

Publication number: WO2024031528A1
Application number: PCT/CN2022/111745
Authority: WO
Inventors: Shahid JAN
Original assignee: Shenzhen Tcl New Technology Co., Ltd.
Priority date: 2022-08-11
Filing date: 2022-08-11
Publication date: 2024-02-15

Abstract

A wireless communication method for sub-band full-duplex (SBFD) operation by a base station includes configuring, by the base station, a time/frequency location and a bandwidth of a pool of sub-bands to user equipments (UEs) in a cell using a radio resource control (RRC) static configuration; and performing, by the base station, an indication and an activation/de-activation of the downlink (DL) or uplink (UL) sub-bands to one or more UEs in the cell using a physical layer signaling comprising of a downlink control information (DCI) or a medium access control (MAC) layer signaling comprising of a MAC control element (CE).

Description

WIRELESS COMMUNICATION DEVICES AND WIRELESS COMMUNICATION METHODS FOR SBFD OPERATION

BACKGROUND OF DISCLOSURE

1. Field of the Disclosure

The present disclosure relates to the field of wireless communication systems, and more particularly, to wireless communication devices and wireless communication methods for sub-band full-duplex (SBFD) operation in 5G NR (new radio) communication system. More specifically, the present disclosure discusses a method of SBFD configuration, where a gNB can configure a pool of sub-bands to user equipments (UEs) in a cell using a radio resource control (RRC) static configuration and perform a dynamic indication and an activation/de-activation of the downlink (DL) or uplink (UL) sub-bands to one or more UEs.

2. Description of the Related Art

SBFD operation is a new feature defined in Release 18, and it has not been defined that how to inform a UE about a time and/or frequency location of sub-bands that a gNB would use for SBFD operation. Re-using the existing methods of conventional TDD configuration for SBFD configuration/indication to the UE may introduce the following challenges. 1. It may increase a higher layer signaling overhead, as for each sub-band, it may be required to configure higher layer signaling. In addition, re-configuration of higher layer signaling may be required in a case if some changes occur in time-frequency locations of DL or UL sub-bands. 2. It may reduce a flexibility of sub-bands, as the sub-bands configuration would fix the sub-bands either to DL or to UL direction in specific time slots/symbol. 3. It may create a co-existence issue of legacy operation and SBFD operation, due to the existence of legacy UE in a cell which uses the conventional TDD configuration. 4. It may increase a complexity of gNB in handling of collision between SSB (DL direction) and UL sub-bands transmission in the same time slots/symbols or collision of PRACH occasion (UL direction) and DL sub-bands transmission in the same time slots/symbols.

In prior art, regarding SBFD time/frequency resources configuration and its indication to UEs, proposals submitted to 3GPP RAN1#109-e meeting were focused on the configuration of DL and UL sub-bands by re-using the existing TDD-UL-DL-ConfigCommon or TDD-UL-DL-ConfigDedicated. However, no proposal of them is focused on, how to reduce the higher layer signaling configuration overhead and how to simplify the configuration procedure.

Therefore, there is a need for wireless communication devices and wireless communication methods to define the configuration, indication and activation/de-activation of the DL or UL sub-bands to one or more UEs in a cell for SBFD operation.

SUMMARY

An object of the present disclosure is to propose wireless communication devices and wireless communication methods for sub-band full-duplex (SBFD) operation, which can solve issues in the prior art, define a method of SBFD configuration, indication and activation/de-activation to one or more UEs in a cell, simplify a configuration procedure, reduce a higher layer signaling overhead, make sub-bands operation more flexible, simplify a process of collision handling between an SSB and an UL sub-band transmission or a PRACH occasion and a DL sub-band transmission, and/or provide a good communication performance.

In a first aspect of the present disclosure, a wireless communication method for sub-band full-duplex (SBFD) operation by a base station includes configuring, by the base station, a time/frequency location and a bandwidth of a pool of sub-bands to the user equipments (UEs) in a cell using a radio resource control (RRC) static configuration; and performing, by the base station, an indication and an activation/de-activation of the downlink (DL) or uplink (UL) sub-bands to one or more UEs in the cell using a physical layer signaling comprising of a downlink control information (DCI) or a medium access control (MAC) layer signaling comprising of a MAC control element (CE) .

In a second aspect of the present disclosure, a base station comprises a memory, a transceiver, and a processor coupled to the memory and the transceiver. The processor is configured to configure a time/frequency location and a bandwidth of a pool of sub-bands to user equipments (UEs) in a cell using a radio resource control (RRC) static configuration; and the processor is configured to perform an indication and an activation/de-activation of the downlink (DL) or uplink (UL) sub-bands to one or more UEs in the cell using a physical layer signaling comprising of a downlink control information (DCI) or a medium access control (MAC) layer signaling comprising of a MAC control element (CE) .

In a third aspect of the present disclosure, a non-transitory machine-readable storage medium has stored thereon instructions that, when executed by a computer, cause the computer to perform the above method.

In a fourth aspect of the present disclosure, a chip includes a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the above method.

In a fifth aspect of the present disclosure, a computer readable storage medium, in which a computer program is stored, causes a computer to execute the above method.

In a sixth aspect of the present disclosure, a computer program product includes a computer program, and the computer program causes a computer to execute the above method.

In a seventh aspect of the present disclosure, a computer program causes a computer to execute the above method.

BRIEF DESCRIPTION OF DRAWINGS

In order to illustrate the embodiments of the present disclosure or related art more clearly, the following figures will be described in the embodiments are briefly introduced. It is obvious that the drawings are merely some embodiments of the present disclosure, a person having ordinary skill in this field can obtain other figures according to these figures without paying the premise.

FIG. 1 is a block diagram of a base stations (e.g., gNBs) of communication in a communication network system according to an embodiment of the present disclosure.

FIG. 2 is a flowchart illustrating a wireless communication method for configuration, indication and activation/de-activation of the DL or UL sub-bands to one or more UEs in a cell, performed by a base station according to an embodiment of the present disclosure.

FIG. 3 is a schematic diagram illustrating an example scenario for sub-band indication and activation/deactivation according to an embodiment of the present disclosure.

FIG. 4 is a schematic diagram illustrating a cascaded sub-bands indication field and activation/deactivation according to an embodiment of the present disclosure.

FIG. 5 is a schematic diagram illustrating alternate bits of DCI for DL/UL sub-bands indication and activation/de-activation according to an embodiment of the present disclosure.

FIG. 6 is a schematic diagram illustrating a MAC CE for sub-bands indication and activation/de-activation to the UE according to an embodiment of the present disclosure.

FIG. 7 is a schematic diagram illustrating an example of MAC CE for sub-bands indication and activation or de-activation to UE1 according to an embodiment of the present disclosure.

FIG. 8 is a schematic diagram illustrating an example of MAC CE for sub-bands indication and activation/de-activation to UE2 according to an embodiment of the present disclosure.

FIG. 9 is a schematic diagram illustrating an example of collision handling between SSB and UL sub-band transmission according to an embodiment of the present disclosure.

FIG. 10 is a schematic diagram illustrating an example of collision handling between a PRACH occasion and a DL sub-band transmission according to an embodiment of the present disclosure.

FIG. 11 is a block diagram of a system for wireless communication according to an embodiment of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure are described in detail with the technical matters, structural features, achieved objects, and effects with reference to the accompanying drawings as follows. Specifically, the terminologies in the embodiments of the present disclosure are merely for describing the purpose of the certain embodiment, but not to limit the disclosure.

The diversified use cases and exponential growth of number of UEs in the next generation wireless communication system have increased the data traffic explosively which leads to the high requirements of spectral efficiency. In order to accomplish these requirements, time division duplex TDD system is widely adopted in commercial NR deployments. TDD system uses a single spectrum (frequency band) for downlink (DL) and uplink (UL) in different time slots, and utilizes the available spectrum more efficiently as compared to the frequency division duplex (FDD) system.

In conventional TDD system, the time domain resources are split between the downlink (DL) , uplink (UL) , and flexible symbols, where the flexible symbols can be used as DL, UL or as a guard period for DL-UL switching. Allocation of a limited time duration for uplink in conventional TDD would result in reduced coverage, increased latency, and reduced capacity. In order to enhance these limitations, 3GPP RAN working group approves a study item in Rel-18, which focus on the feasibility of simultaneous existence of DL and UL, as known an full duplex, or more specifically, sub-band non-overlapping full duplex (SBFD) operation within a conventional TDD band, as given below: Study the sub-band non-overlapping full duplex and potential enhancements on dynamic/flexible TDD (RAN1, RAN4) .

Comparing the features of conventional TDD operation with sub-band full (SBFD) operation, the key objective of SBFD is to allow simultaneous DL and UL transmission in a TDD carrier. However, SBFD operation is a new feature of Rel-18 and allocating the time frequency resources to the sub-bands in a TDD carrier that gNB would use for SBFD operation is still under discussion as given in the following agreement of 3GPP RAN1#109-e meeting: Study the impact/potential enhancements of resource allocation in symbols with sub-bands that gNB would use for SBFD operation.

Furthermore, it is necessary to inform UE about the time-frequency resources location that gNB would use for SBFD operation as given in the following agreement of 3GPP RAN1#109-e meeting: Study whether/how to inform the UE of the time and/or frequency location of sub-bands that gNB would use for SBFD operation.

Regarding the indication of time frequency location of sub-bands to the UE that gNB would use for SBFD operation, several proposals submitted to 3GPP RAN1#109-e meeting were focused on re-using the existing conventional TDD configuration for SBFD operation. However, re-using the existing TDD configuration for SBFD operation may increase the higher layer signaling, and increase the gNB complexity in handling of collision between synchronization signal block (SSB) and UL sub-bands transmission or physical random access channel (PRACH) occasion and DL sub-band transmission at the same time slots/symbols. Therefore, this disclosure further studies a detail method of sub-bands configuration/indication to the UEs in order to reduce the higher layer signaling overhead, simplify the configuration procedure and make the use of sub-bands more flexible.

FIG. 1 illustrates that, in some embodiments, base stations (e.g., gNBs) 10 and 20 for communication in a communication network system 40 according to an embodiment of the present disclosure are provided. The communication network system 40 includes the

base stations

10 and 20. The base station 10 may include a memory 12, a transceiver 13, and a processor 11 coupled to the memory 12 and the transceiver 13. The base station 20 may include a memory 22, a transceiver 23, and a processor 21 coupled to the memory 22 and the transceiver 23. The processor 11or 21 may be configured to implement proposed functions, procedures and/or methods described in this description. Layers of radio interface protocol may be implemented in the

processor

11 or 21. The

memory

12 or 22 is operatively coupled with the

processor

11 or 21 and stores a variety of information to operate the

processor

11 or 21. The

transceiver

13 or 23 is operatively coupled with the

processor

11 or 21, and the

transceiver

13 or 23 transmits and/or receives a radio signal.

The

processor

11 or 21 may include application-specific integrated circuit (ASIC) , other chipset, logic circuit and/or data processing device. The

memory

12 or 22 may include read-only memory (ROM) , random access memory (RAM) , flash memory, memory card, storage medium and/or other storage device. The

transceiver

13 or 23 may include baseband circuitry to process radio frequency signals. When the embodiments are implemented in software, the techniques described herein can be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The modules can be stored in the

memory

12 or 22 and executed by the

processor

11 or 21. The

memory

12 or 22 can be implemented within the

processor

11 or 21 or external to the

processor

11 or 21 in which case those can be communicatively coupled to the

processor

11 or 21 via various means as is known in the art.

In some embodiments, the

processor

11 or 21 is configured to The

processor

11 or 21 is configured to configure a time/frequency location and a bandwidth of a pool of sub-bands to user equipments (UEs) in a cell using a radio resource control (RRC) static configuration; and the

processor

11 or 21 is configured to perform an indication and an activation/de-activation of the downlink (DL) or uplink (UL) sub-bands to one or more UEs in the cell using a physical layer signaling comprising of a downlink control information (DCI) or a medium access control (MAC) layer signaling comprising of a MAC control element (CE) . This can solve issues in the prior art, define a method of SBFD configuration, indication and activation/de-activation to one or more UEs in a cell, simplify a configuration procedure, reduce a higher layer signaling overhead, make sub-bands operation more flexible, simplify a process of collision handling between an SSB and an UL sub-band transmission or a PRACH occasion and a DL sub-band transmission, and/or provide a good communication performance.

FIG. 2 illustrates a wireless communication method 200for configuration, indication and activation/de-activation of the DL or UL sub-bands to one or more UEs in a cell, performed by a base station according to an embodiment of the present disclosure. In some embodiments, the method 200 includes: a block 202, configuring, by the base station, a time/frequency location and a bandwidth of a pool of sub-bands to user equipments (UEs) in a cell using a radio resource control (RRC) static configuration, and a block 204, performing, by the base station, an indication and an activation/de-activation of the downlink (DL) or uplink (UL) sub-bands to one or more UEs in the cell using a physical layer signaling comprising of a downlink control information (DCI) or a medium access control (MAC) layer signaling comprising of a MAC control element (CE) . This can solve issues in the prior art, define a method of SBFD configuration, indication and activation/de-activation to one or more UEs in a cell, simplify a configuration procedure, reduce a higher layer signaling overhead, make sub-bands operation more flexible, simplify a process of collision handling between an SSB and an UL sub-band transmission or a PRACH occasion and a DL sub-band transmission, and/or provide a good communication performance.

In some embodiments, the RRC static configuration is used to configure SBFD time frequency resources to the UEs in the cell. In some embodiments, the pool of sub-bands is in time slots or symbols, where the time slots or symbols are DL time slots or symbols, UL time slots or symbols, or flexible time slots or symbols. In some embodiments, the RRC static configuration comprises a TDD-Subband-ConfigCommon information element (IE) . In some embodiments, the DCI comprises a sub-band indication field and/or a sub-band activation/de-activation field. In some embodiments, the sub-band indication field is utilized as a single UE specific or UE’s group specific and comprises of N bits in the form of bitmap, wherein N is a number of sub-bands configured by the RRC static configuration, and each bit of the bitmap is associated to one sub-band. In some embodiments, the indication of the DL or UL sub-bands is from the bits of the bitmap.

In some embodiments, a first value for a bit of the bitmap indicates a DL sub-band to the one or more UEs in the cell, and a second value for a bit of the bitmap indicates an UL sub-band to the one or more UEs in the cell. In some embodiments, the sub-band activation/de-activation field is utilized as a single UE specific and comprises of N bits in the form of bitmap, where N number of bits of the sub-band activation/de-activation field is equal to the N number of bits of the sub-band indication field. In some embodiments, the sub-band activation/de-activation field provides a bitmap to one UE where each bit of the bitmap is associated to an activation/de-activation of one sub-band. In some embodiments, a first value for a bit of the bitmap activates the DL or UL sub-bands to the UE, and a second value for a bit of the bitmap de-activates the DL or UL sub-bands to the UE.

In some embodiments, the base station uses a first DCI for the indication of the DL or UL sub-bands to the one or more UEs, and the base station uses a second DCI for the activation/de-activation of the DL or UL sub-bands to the one or more UEs. In some embodiments, the first DCI is UE’s group specific which transmits the sub-band indication field to inform the DL or UL sub-bands to a group of UEs. In some embodiments, the second DCI is UE specific which transmits the sub-band activation/de-activation field to each UE to activate or de-activate the DL or UL sub-bands. In some embodiments, the first DCI is a group common DCI with cyclic redundancy check (CRC) scrambled by a new sub-band indication-radio network temporary identifier (SBI-RNTI) , and/or the second DCI is a UE specific DCI with CRC scrambled by a new SBI RNTI.

In some embodiments, the base station uses a UE specific DCI with CRC scrambled by a new SBI RNTI for the indication and the activation/de-activation of the DL or UL sub-bands to the one or more UEs. In some embodiments, the UE specific DCI transmits the bitmaps of the sub-band indication field and the sub-band activation/de-activation field one after the other, where a first field of the bitmaps is to indicate the DL or UL sub-bands to the UE and the second field of the bitmaps is to activate or de-activate the DL or UL sub-bands to the UE. In some embodiments, the base station uses alternate bits of the sub-band indication field and the sub-band activation/de-activation field of the UE specific DCI to perform the indication and the activation/de-activation of the DL or UL sub-bands.

In some embodiments, the MAC CE comprises a sub-band indication field and/or a sub-band activation/de-activation field. In some embodiments, the sub-band indication field of the MAC CE indicates an identity of sub-bands to the one or more UEs, and a length of the sub-band indication field of the MAC CE is up to 4 bits and varies according to a number of the sub-bands configured by the RRC static configuration. In some embodiments, a bit in the sub-bands indication field of the MAC CE is set to a first value to indicate a DL sub-band, which is mapped to the position of the bit , to the UE, and a bit is set to a second value to indicate an UL sub-band, which is mapped to the position of the bit, to the UE. In some embodiments, the sub-band activation/de-activation field of the MAC CE activates/de-activates the DL or UL sub-bands, and a length of the sub-band activation/de-activation field of the MAC CE depends on the length of the sub-band indication field of the MAC CE. In some embodiments, a bit in the sub-band activation/de-activation field is set to a first value to activate a DL or UL sub-band, which is mapped to the position of the bit, to the UE, and a bit is set to a second value to de-activate a DL or UL sub-band, which is mapped to the position of the bit, to the UE.

In some embodiments, the MAC CE comprises one octet to perform the indication and the activation/de-activation of the DL or UL sub-bands. In some embodiments, if a number of bits in the sub-band indication field and the sub-band activation/de-activation field of the MAC CE is less than one octet, a bit location which is not mapped to any sub-band indication or activation/de-activation is left empty.

In some embodiments, the DCI or the MAC CE is further utilized by the base station to handle a collision between a synchronization signal block (SSB) transmission with an UL sub-band transmission in same time slots or symbols and a collision between a physical random access channel (PRACH) occasion with a DL sub-band transmission in same time slots or symbols. In some embodiments, when an SSB region is configured in resource blocks (RBs) of one sub-band, the base station indicates another sub-band for UL transmission using the DCI or the MAC CE. In some embodiments, when a PRACH region is configured in RBs of one sub-band, the base station indicates another sub-band for DL transmission using the DCI or the MAC CE.

Some embodiments of this disclosure define a new method of SBFD configuration to inform one or more UEs about the time and/or frequency location of sub-bands that a network/gNB would use for SBFD operation. In this exemplarily method, the network/gNB would use a higher layer RRC static configuration to configure the time/frequency location and bandwidth of a pool of sub-bands to all SBFD operation’s UEs in a cell, and the network/gNB would further use physical layer signaling i.e., DCI or MAC layer signaling i.e., MAC CE to indicate and activate/de-activate the DL/UL sub-bands to one or more UEs in a cell. The main objective of this new configuration method is to simplify the higher layer configuration for SBFD operation, reduce the higher layer signaling overhead, and make the SBFD configuration more flexible. Some embodiments explain the static configuration of time and/or frequency location of a pool of sub-bands through RRC higher layer configuration. Some embodiments explain the DL/UL Sub-bands indication and activation/de-activation through DCI or MAC CE. Some embodiments explain the collision handling between SSB and UL sub-bands transmission at the same time slots/symbols, and collision handling between PRACH occasion and DL sub-bands transmission at the same time slots/symbols.

Static Configuration of SBFD Time Frequency Resources to the Cells:

In this embodiment, static configuration of SBFD time frequency resource location and bandwidth of sub-bands are defined, where higher layer RRC signaling is used to configure the SBFD time frequency resources to all UEs in a cell. Moreover, in this configuration, a pool of sub-bands is defined in specific time slots or symbols, where the time slots or symbols can be UL time slots or symbols, DL time slots or symbols, or flexible time slots or symbols.

The following IE TDD-Subbands-ConfigCommon determines the cell specific configuration of a pool of sub-bands to all UEs in a cell as given below.

TDD-Subband-ConfigCommon Information Element:

The description of the configuration IE of sub-band’s pool is given Table 1.

Table 1: Subbands Pool Time Frequency Occupation Field Description

Sub-band Indication and Activation/De-activation:

Some embodiments of the present disclosure explain indication and activation/deactivation of configured DL/UL sub-bands resources to one or more UEs by using either physical layer signaling i.e., DCI or MAC layer signaling i.e., MAC CE. Some embodiments explain the DL/UL sub-bands indication and its activation or de-activation to one or more UEs in a cell through DCI. Some embodiments explain the DL/UL sub-bands indication and its activation or de-activation to one or more UEs in a cell through MAC CE.

Sub-bands Indication and Activation/Deactivation via DCI:

In this embodiment of the present disclosure, a network/gNB can use downlink control information (DCI) to indicate the configured sub-bands resources according to the UEs DL or UL traffic direction and activate/deactivate the DL/UL sub-bands to one or more UEs in a cell. For this purpose, the DCI fields which contains the indication and activation/de-activation information, and its transmission procedure are explained below in details.

For indication and activation/de-activation of DL/UL sub-bands, the following information is transmitted by means of the DCI. 1. Sub-bands indication field: The sub-band indication field of DCI can be utilized as a single UE specific or UE’s group specific and it may comprise of N bits in the form of bitmap, where N is the number of sub-bands configured by higher layers as explained in the above embodiment. The N bits of sub-bands indication field of DCI provides a bitmap to one or more UEs in a cell, where each bit of the bitmap is associated to a sub-band. The UE may assume the following information from the bitmap of a sub-band indication field. 1. Number of sub-bands from the N number of bits: For instance, if the number of bits in the bitmap of sub-bands indication field is two, the UE may assume that two sub-bands are configured in the TDD band. Similarly, if the number of bits in the bitmap of a sub-band indication field is three, the UE may assume that three sub-bands are configured in the TDD band. 2. Indication of the DL or UL sub-bands from the bits of the bitmap: This embodiment of this disclosure proposes that a value of ‘1’ for a bit of the bitmap indicates a DL sub-band to one or more UEs in a cell, and a value of ‘0’ for a bit of the bitmap indicates an UL sub-band to one or more UEs in a cell as given in table 2.

Table 2: DCI based bitmap description of DL/UL sub-bands indication field

2. Sub-bands activation/de-activation field: The sub-band activation/de-activation field of DCI can be utilized as a single UE specific, and it may comprise of N bits, where N number of bits is equal to the N number of bits of sub-band indication field. In other words, the number of bits in sub-bands activation/de-activation field depends on the number of bits in sub-band indication field. For instance, if the number of bits in sub-band indication field is three, the number of bits in sub-band activation/de-activation field is also three. A sub-band activation/de-activation field of DCI provides a bitmap to a UE (UE specific) where each bit of the bitmap is associated to the activation/de-activation of a sub-band. This embodiment of this disclosure proposes that a value of ‘1’ for a bit of the bitmap indicates activation of a DL or UL sub-band to a UE, and a value of ‘0’ for a bit of the bitmap indicates de-activation of an DL or UL sub-band to a UE as shown in the following table 3.

Table 3: DCI based bitmap description of DL/UL sub-bands activation/de-activation

For DCI transmission to carry the information of sub-bands indication and activation/de-activation of DL/UL sub-bands to one or more UEs, some embodiments of this disclosure propose the following two approaches. In addition, some embodiments of this disclosure consider to re-use the existing DCIs. However, to differentiate the sub-bands indication and activation/de-activation function from the other functions which is performed by the existing DCIs, some embodiments of this disclosure propose to use a new RNTI such as sub-band indication (SBI) RNTI.

In an approach 1, the network/gNB uses two DCIs for indication and activation/deactivation purposes respectively. The first DCI is UE’s group specific which transmits the sub-bands indication field in order to inform the DL/UL sub-bands indication to a group of UEs. The second DCI is UE specific which transmits the sub-band activation/de-activation field to each UE, in order to activate or de-activate the DL/UL sub-bands. FIG. 3 is a schematic diagram illustrating an example scenario for sub-band indication and activation/deactivation according to an embodiment of the present disclosure. For instance, consider a scenario, where the network/gNB needs to inform the indication of three DL/UL sub-bands to UE1 and UE2 in a cell, and perform the activation of two DL sub-bands to UE1 and one UL sub-band to UE2 as shown in FIG. 3.

To indicate the DL/UL sub-band to the UE1 and UE2, a UEs groups common DCI such as DCI format 2_0 can be used to transmit the DL/UL sub-bands indication. Since DCI format 2_0 is used in the current specification for slot format indication, hence the DCI format 2_0 with CRC can be scrambled by a new SBI RNTI to differentiate the sub-bands indications from the slot format indication. In this case, the following indication fields can be used for DL-UL sub-band to a group of UEs i.e., UE1 and UE2 as given in table 4.

Table 4: Example of Sub-bands indication to a group of UEs

To activate or de-activate the DL or UL sub-bands, the UE specific DCI with CRC scrambled by new SBI RNTI can be used to transmit the sub-band activation/deactivation field. In this case, the following DCIs for UE1 and UE2 can be used to transmit the activation/de-activation fields as given in table 5 and table 6 respectively.

Table 5: Example of DCI based sub-band activation/de-activation of UE1

Table 6: Example of DCI based sub-band activation/deactivation to UE2

The advantage of approach 1 is that it reduces the overall payload of DCI i.e., the number of bits in the DCI. However, in this method, the number of physical layer signaling i.e., DCI transmission is more than the second approach e.g., three DCIs transmission in the above example.

In the approach 2, a network/gNB can use UE specific DCI with CRC scrambled by new SBI RNTI to perform DL/UL sub-bands indication and its activation/de-activation. For this purpose, the aforementioned DCI fields, i.e., sub-band indication field and sub-band activation/deactivation field can be transmitted by means of UE specific DCI to each UE which is interested in SBFD operation. The advantage of approach 2 is that it reduces the number of signaling as compared to approach 1. However, in approach 2, the payload of DCI or the bits of DCI are more than approach 1. For approach 2, some embodiments of this disclosure propose the following two possible options for indication and activation/de-activation through UE specific DCI.

Option 1:

FIG. 4 is a schematic diagram illustrating a cascaded sub-bands indication field and activation/deactivation according to an embodiment of the present disclosure. In the option 1 of approach 2, the network/gNB can use the bitmap of DL/UL sub-bands indication field and DL/UL sub-bands activation/de-activation fields in cascaded form as shown in figure 4. In other words, UE specific DCI can transmit the bitmap of the sub-band indication field and sub-band activation/de-activation field one after the other, where the first field is to indicate the DL/UL sub-bands and the second field is to activate or de-activate the DL/UL sub-bands to a UE as shown in FIG. 4.

For instance, consider the scenario of FIG. 3, where the network/gNB needs to inform the indication of three DL/UL sub-bands to UE1 and UE2 in a cell, and perform the activation of two DL sub-bands to UE1 and one UL sub-band to UE2. For indication and activation /de-activation the DL/UL sub-band to the UEs i.e., UE1 and UE2, UE specific DCI, with CRC scrambled by new SBI RNTI, which comprises of sub-band indication field and sub-band activation/de-activation field, can be transmitted to each UE. Since here the number of UEs are two, i.e., UE1 and UE2, the network/gNB can transmit two DCIs to perform indication and activation/deactivation of sub-bands to UE1 and UE2. The indication of three DL/UL sub-bands and activation of two DL sub-bands to UE1 is given in table 7. The indication of three DL/UL sub-bands and activation of one UL sub-band to UE2 is given in table 8.

Table 7: Example of 3 DL-UL sub-bands Indication and 2 DL sub-bands activation to UE1

Table 8: Example of 3 DL-UL sub-bands Indication and 1 UL sub-bands activation to UE2

The advantage of option 1 in approach 2 is that it decouples the bitmaps of the two fields and simplify the decoding mechanism of UE for indication and activation/de-activation.

Option 2:

FIG. 5 is a schematic diagram illustrating alternate bits of DCI for DL/UL sub-bands indication and activation/de-activation according to an embodiment of the present disclosure. In the option 2 of approach 2, the network/gNB can use alternate bits of the DL/UL sub-band indication and activation/de-activation fields of UE specific DCI to indicate and activate/de-active the DL/UL sub-bands to a UE as shown in FIG. 5.

For instance, consider the scenario of FIG. 3, where the network/gNB needs to inform the indication of three DL/UL sub-bands to UE1 and UE2 in a cell, and perform the activation of two DL sub-bands to UE1 and one UL sub-band to UE2. For indication and activation/de-activation the DL/UL sub-bands to the UEs i.e., UE1 and UE2, UE specific DCI, with CRC scrambled by new SBI RNTI, which comprises of alternate bits for indication of DL/UL sub-band, and activation/de-activation of DL/UL sub-bands can be transmitted to each UE. Since here the number of UEs are two, i.e., UE1 and UE2, the network/gNB can transmit two DCIs to perform indication and activation/deactivation of sub-bands to UE1 and UE2. The indication of three DL/UL sub-bands and activation of two DL sub-bands to UE1 is given in table 9. The indication of three DL/UL sub-bands and activation of one UL sub-band to UE2 is given in table 10.

Table 9: Example of 3 DL/UL sub-bands Indication and 2 DL sub-bands activation to UE1 with alternate bits

Table 10: Example of 3 DL/UL sub-bands Indication and 1 UL sub-band activation to UE2 with alternate bits

The advantage of option 2 is that each UE can get the required information by decoding less number of bits. However, the option 2 is complicated as compared to the option 1.

Sub-band Indication and Activation/De-activation via MAC CE:

FIG. 6 is a schematic diagram illustrating a MAC CE for sub-bands indication and activation/de-activation to the UE according to an embodiment of the present disclosure. In this embodiment of the present disclosure, the network/gNB uses the MAC layer signaling to indicate and activate/deactivate the configured sub-band resources of the DL/UL sub-bands to one or more UEs in a cell by sending the indication and activation/de-activation through the MAC CE. For this purpose, some embodiments of this disclosure propose a new MAC CE which is consist of a single octet as shown in FIG. 6.

For sub-band indication and activation/de-activation, the following information can be transmitted by means of MAC CE.

1. Sub-bands indication field: This field indicates the identity of sub-bands to one or more UEs e.g., whether the sub-band is a DL sub-band or UL sub-band. The length of this field is up to 4 bits, and it can vary according to the number of sub-bands configured by the higher layer. For instance, if the number of sub-bands configured by the higher layer is three, the length of sub-ban indication field in MAC CE is 3 bits. In addition, the bit in the sub-band indication field of the MAC CE is set to 1 to indicate the DL sub-bands and the bit of the MAC CE field is set to 0 to indicate UL sub-bands. For instance, if a bit in a specific location is set to ‘1’ , it indicates a DL sub-band which is mapped to the position of the bit, and if a bit in a specific location is set ‘0’ , it indicates an UL sub-band which is mapped to the position of the bit.

2. Sub-bands activation/de-activation field: This field activates/de-activates the DL/UL sub-bands. The length of this field depends on the length of sub-band indication field. For instance, if the length of sub-band indication field is three bits, the length of the sub-band indication field may also be considered as three bits. In addition, the sub-band activation and de-activation is configured by a bitmap. If a bit in a specific location is set ‘1’ , it activates a DL or UL sub-band which is mapped to the position of the bit. If the bit is set to be ‘0’ , it deactivates a DL or UL sub-band mapped to the position of the bit.

For MAC CE transmission to carry the information of sub-bands indication and activation/de-activation for one or more UEs in a cell, some embodiments of this disclosure consider the example scenario of FIG. 3, where the network/gNB needs to inform the indication of three DL/UL sub-bands to UE1 and UE2 in a cell, and to perform the activation of two DL sub-bands to UE1 and one UL sub-band to UE2. FIG. 7 is a schematic diagram illustrating an example of MAC CE for sub-bands indication and activation or de-activation to UE1 according to an embodiment of the present disclosure. FIG. 8 is a schematic diagram illustrating an example of MAC CE for sub-bands indication and activation/de-activation to UE2 according to an embodiment of the present disclosure. In this case, to indicate and activate/de-activate the DL/UL sub-band to the UEs i.e., UE1 and UE2, UE specific MAC CE comprises of one octet can be transmitted to UE1 and UE2 as shown in FIG. 7 and FIG. 8 respectively. As mentioned above, that MAC CE defined for DL/UL sub-bands indication and activation de-activation is comprises of one octet. In case the number of bits in the DL/UL sub-band indication field and DL/UL sub-bands activation/de-activation field is less than octet i.e., 8 bits, the bit locations which is not mapped to any sub-band indication or activation/de-activation will be left empty. For instance, in the above example the number of bits in the indication and activation/de-activation fields are three in each field. Therefore, the 4th bit location of each field is empty as shown in FIG. 7 and FIG. 8.

Collision handling between SSB with UL sub-band and PRACH occasion with DL sub-band:

Some embodiments of the present disclosure discuss potential enhancement for SBFD operation, where a DCI based indication, or a MAC CE based indication of the DL/UL sub-bands can be utilize by the network/gNB to handle a collision between an SSB transmission with an UL sub-band transmission in the same time slots/symbols and a collision between a PRACH occasion with a DL sub-band transmission in the same time slots/symbols.

Time domain overlapping of SSB and UL transmission direction:

In current specification, the time domain position of the transmitted SSBs in a frame with SS/PBCH blocks is indicated via system information, and the UE doses not perform the UL transmission i.e., the UE does not transmit PUSCH, PUCCH, or PRACH in the slots/symbols if the UL transmission is overlapped with SS/PBCH blocks in time domain (refer to TS 38.213, clause 11.1) .

Based on this restriction, some embodiments of this disclosure consider that a gNB should not indicate a sub-band as UL sub-band where the SSB is overlapped with the RBs of UL sub-bands. Since the proposed methods in the above embodiments do not restrict the DL and UL sub-bands to a specific sub-band, and it defines a pool of sub-bands which can be indicated and activated/de-activated as DL or UL sub-bands. Hence, when the SSB region is configured in the RBs of a sub-band, the gNB can indicate another sub-band for UL transmission using the DCI based indication or the MAC CE based indication. FIG. 9 is a schematic diagram illustrating an example of collision handling between SSB and UL sub-band transmission according to an embodiment of the present disclosure. For instance, if the SSB is configured in RBs location of sub-band#0, the gNB can indicate sub-band#1 and/or sub-band#2 as UL sub-band to the UE using DCI based indication or MAC CE based indication as shown in FIG. 9.

Time domain overlapping of PRACH and DL direction:

In a similar or the same way, when the PRACH region is configured in RBs of a sub-band, the gNB can indicate another sub-band for DL transmission using the DCI based indication or the MAC CE based indication as explained in the above embodiments. FIG. 10 is a schematic diagram illustrating an example of collision handling between a PRACH occasion and a DL sub-band transmission according to an embodiment of the present disclosure. For instance, if the PRACH is configured in the RBs location of sub-band#1, the gNB can indicate sub-band#0 and/or sub-band#2 as DL sub-band to the UE using the DCI based indication or the MAC CE based indication as shown in FIG. 10.

In summary, the main objective of some embodiments of the present disclosure is to simplify the configuration procedure of SBFD operation, reduce the higher signaling overhead and make the sub-bands operation more flexible. The proposed solutions to achieve our objectives are summarized as below. 1. RRC static configuration for SBFD time/frequency resources has utilized in order to configure a pool of sub-bands to the UEs in a cell explicitly. 2. Physical layer signaling and MAC layer signaling are used for indication and activation de-activation of DL/UL sub-bands to one or more UEs as explained below. DCI based bitmap is used to perform indication and activation/de-activation of DL/UL sub-bands to one or more UEs. MAC CE based mechanism is used to perform indication and activation/de-activation of DL/UL sub-bands to one or more UEs. 3. Methods of handling collision between SSB and UL sub-bands transmission and PRACH occasion and DL sub-band transmission are proposed. Some embodiments of the present disclosure propose a new method of SBFD configuration and its indication to the UEs and have the following advantages: 1. The proposed methods and solutions simplify the configuration procedure of SBFD operation. 2. The proposed methods and solutions reduce the higher layer configuration overhead. 3. The proposed methods and solutions make the sub-bands operation more flexible. 4. The proposed solutions reduce the complexity of co-existence of legacy UE and SBFD capable UE and help in collision handling between DL and UL transmission in more efficient way.

FIG. 11 is a block diagram of an example system 700 for wireless communication according to an embodiment of the present disclosure. Embodiments described herein may be implemented into the system using any suitably configured hardware and/or software. FIG. 11 illustrates the system 700 including a radio frequency (RF) circuitry 710, a baseband circuitry 720, an application circuitry 730, a memory/storage 740, a display 750, a camera 760, a sensor 770, and an input/output (I/O) interface 780, coupled with each other at least as illustrated. The application circuitry 730 may include a circuitry such as, but not limited to, one or more single-core or multi-core processors. The processors may include any combination of general-purpose processors and dedicated processors, such as graphics processors, application processors. The processors may be coupled with the memory/storage and configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems running on the system.

While the present disclosure has been described in connection with what is considered the most practical and preferred embodiments, it is understood that the present disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements made without departing from the scope of the broadest interpretation of the appended claims.

Claims

A wireless communication method for sub-band full-duplex (SBFD) operation by a base station, comprising:

configuring, by the base station, a time/frequency location and a bandwidth of a pool of sub-bands to user equipments (UEs) in a cell using a radio resource control (RRC) static configuration; and

performing, by the base station, an indication and an activation/de-activation of the downlink (DL) or uplink (UL) sub-bands to one or more UEs in the cell using a physical layer signaling comprising of a downlink control information (DCI) or a medium access control (MAC) layer signaling comprising of a MAC control element (CE) .
The wireless communication method according to claim 1, wherein the RRC static configuration is used to configure SBFD time frequency resources to the UEs in the cell.
The wireless communication method according to claim 1 or 2, wherein the pool of sub-bands is in time slots or symbols, where the time slots or symbols are DL time slots or symbols, UL time slots or symbols, or flexible time slots or symbols.
The wireless communication method according to any one of claims 1 to 3, wherein the RRC static configuration comprises a TDD-Subband-ConfigCommon information element (IE) .
The wireless communication method according to claim 1, wherein the DCI comprises a sub-band indication field and/or a sub-band activation/de-activation field.
The wireless communication method according to claim 5, wherein the sub-band indication field is utilized as a single UE specific or UE’s group specific and comprises of N bits in the form of bitmap, wherein N is a number of sub-bands configured by the RRC static configuration, and each bit of the bitmap is associated to one sub-band.
The wireless communication method according to claim 6, wherein the indication of the DL or UL sub-bands is from the bits of the bitmap.
The wireless communication method according to claim 6 or 7, wherein a first value for a bit of the bitmap indicates a DL sub-band to the one or more UEs in the cell, and a second value for a bit of the bitmap indicates an UL sub-band to the one or more UEs in the cell.
The wireless communication method according to claim 5, wherein the sub-band activation/de-activation field is utilized as a single UE specific and comprises of N bits in the form of bitmap, where N number of bits of the sub-band activation/de-activation field is equal to the N number of bits of the sub-band indication field.
The wireless communication method according to claim 9, wherein the sub-band activation/de-activation field provides a bitmap to one UE where each bit of the bitmap is associated to an activation/de-activation of one sub-band.
The wireless communication method according to claim 9 or 10, wherein a first value for a bit of the bitmap activates the DL or UL sub-bands to the UE, and a second value for a bit of the bitmap de-activates the DL or UL sub-bands to the UE.
The wireless communication method according to any one of claims 5 to 11, wherein the base station uses a first DCI for the indication of the DL or UL sub-bands to the one or more UEs, and the base station uses a second DCI for the activation/de-activation of the DL or UL sub-bands to the one or more UEs.
The wireless communication method according to claim 12, wherein the first DCI is UE’s group specific which transmits the sub-band indication field to inform the DL or UL sub-bands to a group of UEs.
The wireless communication method according to claim 12 or 13, wherein the second DCI is UE specific which transmits the sub-band activation/de-activation field to each UE to activate or de-activate the DL or UL sub-bands.
The wireless communication method according to any one of claims 12 to 14, wherein the first DCI is a group common DCI with cyclic redundancy check (CRC) scrambled by a new sub-band indication-radio network temporary identifier (SBI-RNTI) , and/or the second DCI is a UE specific DCI with CRC scrambled by a new SBI RNTI.
The wireless communication method according to any one of claims 5 to 11, wherein the base station uses a UE specific DCI with CRC scrambled by a new SBI RNTI for the indication and the activation/de-activation of the DL or UL sub-bands to the one or more UEs.
The wireless communication method according to claim 16, wherein the UE specific DCI transmits the bitmaps of the sub-band indication field and the sub-band activation/de-activation field one after the other, where a first field of the bitmaps is to indicate the DL or UL sub-bands to the UE and the second field of the bitmaps is to activate or de-activate the DL or UL sub-bands to the UE.
The wireless communication method according to claim 16, wherein the base station uses alternate bits of the sub-band indication field and the sub-band activation/de-activation field of the UE specific DCI to perform the indication and the activation/de-activation of the DL or UL sub-bands.
The wireless communication method according to claim 5, wherein the MAC CE comprises a sub-band indication field and/or a sub-band activation/de-activation field.
The wireless communication method according to claim 18, wherein the sub-band indication field of the MAC CE indicates an identity of sub-bands to the one or more UEs, and a length of the sub-band indication field of the MAC CE is up to 4 bits and varies according to a number of the sub-bands configured by the RRC static configuration.
The wireless communication method according to claim 20, wherein a bit in the sub-bands indication field of the MAC CE is set to a first value to indicate a DL sub-band, which is mapped to the position of the bit , to the UE, and a bit is set to a second value to indicate an UL sub-band, which is mapped to the position of the bit, to the UE.
The wireless communication method according to claim 19 or 21, wherein the sub-band activation/de-activation field of the MAC CE activates/de-activates the DL or UL sub-bands, and a length of the sub-band activation/de-activation field of the MAC CE depends on the length of the sub-band indication field of the MAC CE.
The wireless communication method according to claim 22, wherein a bit in the sub-band activation/de-activation field is set to a first value to activate a DL or UL sub-band, which is mapped to the position of the bit, to the UE, and a bit is set to a second value to de-activate a DL or UL sub-band, which is mapped to the position of the bit, to the UE.
The wireless communication method according to any one of claims 19 to 24, wherein the MAC CE comprises one octet to perform the indication and the activation/de-activation of the DL or UL sub-bands.
The wireless communication method according to claim 24, wherein if a number of bits in the sub-band indication field and the sub-band activation/de-activation field of the MAC CE is less than one octet, a bit location which is not mapped to any sub-band indication or activation/de-activation is left empty.
The wireless communication method according to any one of claims 5 to 25, wherein the DCI or the MAC CE is further utilized by the base station to handle a collision between a synchronization signal block (SSB) transmission with an UL sub-band transmission in same time slots or symbols and a collision between a physical random access channel (PRACH) occasion with a DL sub-band transmission in same time slots or symbols.
The wireless communication method according to claim 26, wherein when an SSB region is configured in resource blocks (RBs) of one sub-band, the base station indicates another sub-band for UL transmission using the DCI or the MAC CE.
The wireless communication method according to claim 26 or 27, wherein when a PRACH region is configured in RBs of one sub-band, the base station indicates another sub-band for DL transmission using the DCI or the MAC CE.
A base station, comprising:

a memory;

a transceiver; and

a processor coupled to the memory and the transceiver;

wherein the processor is configured to execute the method of any one of claims 1 to 28.
A non-transitory machine-readable storage medium having stored thereon instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1 to 28.
A chip, comprising:

a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the method of any one of claims 1 to 28.
A computer readable storage medium, in which a computer program is stored, wherein the computer program causes a computer to execute the method of any one of claims 1 to 28.
A computer program product, comprising a computer program, wherein the computer program causes a computer to execute the method of any one of claims 1 to 28.
A computer program, wherein the computer program causes a computer to execute the method of any one of claims 1 to 28.