WO2024171521A1 - Base station, terminal, and communication method - Google Patents

Abstract

A base station comprising: a control circuit which changes a resource in a control channel region when at least some resources in the control channel region cannot be used for a downlink control channel; and a transmission circuit which transmits a signal of the downlink control channel in a resource in the control channel region.

Description

Base station, terminal and communication method

This disclosure relates to a base station, a terminal, and a communication method.

The 3rd Generation Partnership Project (3GPP) has completed the formulation of the physical layer specifications for Release 17 NR (New Radio access technology) as a functional extension of 5th generation mobile communication systems (5G). NR will support enhanced mobile broadband (eMBB) to meet the requirements of high speed and large capacity, as well as functions that realize ultra-reliable and low latency communication (URLLC) (see, for example, non-patent literature 1-5).

3GPP TS 38.211 V17.4.0, "NR; Physical channels and modulation (Release 17)," December 2022 3GPP TS 38.212 V17.4.0, "NR; Multiplexing and channel coding (Release 17)," December 2022 3GPP TS 38.213 V17.4.0, "NR; Physical layer procedure for control (Release 17)," December 2022 3GPP TS 38.214 V17.4.0, "NR; Physical layer procedures for data (Release 17)," December 2022 3GPP TS 38.331 V17.3.0, "NR; Radio Resource Control (RRC) protocol specification (Release 17)", December 2022

However, there is room for further study regarding resource allocation methods in wireless communications.

Non-limiting examples of the present disclosure contribute to providing a base station, a terminal, and a communication method that can appropriately allocate resources in wireless communication.

A base station according to one embodiment of the present disclosure includes a control circuit that changes the resources of a control channel region when at least a portion of the resources of the control channel region is unavailable for a downlink control channel, and a transmission circuit that transmits a signal of the downlink control channel using the resources of the control channel region.

These comprehensive or specific aspects may be realized as a system, device, method, integrated circuit, computer program, or recording medium, or as any combination of a system, device, method, integrated circuit, computer program, and recording medium.

According to one embodiment of the present disclosure, resource allocation in wireless communication can be performed appropriately.

Further advantages and benefits of an embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and/or benefits may be provided by some of the embodiments and features described in the specification and drawings, respectively, but not necessarily all of them need be provided to obtain one or more identical features.

Diagram showing an example of the Duplex method A block diagram showing an example of the configuration of a portion of a base station. Block diagram showing a partial configuration example of a terminal Block diagram showing a configuration example of a base station Block diagram showing an example of a terminal configuration A sequence diagram showing an example of the operation of a base station and a terminal. Diagram showing examples of conditions under which Physical Downlink Control Channel (PDCCH) resources can be allocated A diagram showing an example of Control Resource Set (CORESET) settings A diagram showing an example of CORESET settings A diagram showing an example of CORESET settings A diagram showing an example of CORESET settings A diagram showing an example of CORESET settings A diagram showing an example of PDCCH candidate settings in CORESET A diagram showing an example of PDCCH candidate settings in CORESET Diagram of an example architecture for a 3GPP NR system Schematic diagram showing functional separation between NG-RAN (Next Generation - Radio Access Network) and 5GC (5th Generation Core) Sequence diagram of Radio Resource Control (RRC) connection setup/reconfiguration procedure Schematic diagram showing usage scenarios for enhanced Mobile BroadBand (eMBB), massive Machine Type Communications (mMTC), and Ultra Reliable and Low Latency Communications (URLLC). Block diagram illustrating an example 5G system architecture for a non-roaming scenario

The following describes in detail the embodiments of this disclosure with reference to the drawings.

[About Subband non-overlapping full duplex (SBFD)]
"Study on evolution of NR duplex operation" was approved as a Study Item for Release 18. One of the main topics of this Study Item is support for subband non-overlapping full duplex (SBFD, also known as Cross Division Duplex (XDD)).

Figure 1 shows an example of the Duplex method. In Figure 1, the vertical axis represents frequency, and the horizontal axis represents time. Also, in Figure 1, "U" represents uplink transmission, and "D" represents downlink transmission.

Figure 1(a) shows an example of half duplex Time Division Duplex (TDD). In Figure 1(a), a terminal (UE: User Equipment) is a terminal connected to a base station (e.g., a gNB). In the half duplex shown in Figure 1(a), the transmission direction (e.g., downlink or uplink) in a certain time resource may be common between the base station and the terminal. For example, the transmission direction in a certain time resource does not differ between terminals.

Figure 1(b) shows an example of SBFD. In SBFD, a frequency resource (or a frequency band) is divided into multiple bands (e.g., subbands, RB sets, subbands, or sub-BWPs (Bandwidth parts)), and transmission in different directions (e.g., downlink or uplink) is supported for each subband. In SBFD, a terminal transmits and receives either uplink or downlink in a certain time resource, but does not transmit or receive in the other. On the other hand, in SBFD, a base station can transmit and receive in uplink and downlink simultaneously. In addition, there may be cases where a terminal does not use resources in the transmission direction in a certain time resource (e.g., resources shown by dotted lines in Figure 1(b)).

Note that although omitted in Figure 1, a guard band may be placed between the uplink band (UL sub-band: U) and the downlink sub-band (DL sub-band: D). The guard band may be used to reduce interference (CLI: Cross link interference) between different transmission directions (links).

In the following explanation, a symbol in which the SBFD subband is allocated is called an "SBFD symbol", and a symbol in which the SBFD subband is not allocated is called a "non-SBFD symbol".

Furthermore, the subband configuration is expressed as {X...X}, where X represents the UL subband (U) or DL subband (D). The order of notation corresponds to the order in which the subbands are arranged. For example, the subband configuration in Figure 1(b) is expressed as {DUD}.

[Physical Downlink Control Channel (PDCCH) resources]
The time and frequency domain resources in which the downlink control channel (PDCCH) can be arranged are called a "CORESET (Control resource set, control channel region)."

CORESET can accommodate multiple PDCCH resources, and a terminal may be configured to attempt to receive multiple PDCCHs. A PDCCH that a terminal attempts to receive is called a "PDCCH candidate" (or a PDCCH allocation candidate). PDCCHs are not always transmitted to each terminal, and may not be transmitted depending on the presence or absence of control information for the terminal, the usage status of PDCCH resources, etc. A terminal, for example, decodes (e.g., blind decode (BD)) the configured PDCCH candidate, and if the decoding is successful, recognizes that control information addressed to that terminal has been transmitted.

Parameters such as the number and positions of PDCCH candidates placed in the CORESET may be set, for example, by configuring a search space (SS). In the search space configuration, in addition to setting the PDCCH candidates, the timing (also called the monitoring occasion) at which the terminal receives the CORESET (or PDCCH) is set, for example. In addition, multiple search spaces can be set in one CORESET.

The index (CCE index) of the top Control Channel Element (CCE) in which the PDCCH candidate is arranged may be calculated by, for example, the following formula.

The maximum number of PDCCH candidates (or maximum number of blind decodes) and the maximum number of CCEs to be received per slot and per serving cell may be defined or set. For example, when the subcarrier spacing (SCS) is 15 kHz, the maximum number of PDCCH candidates may be defined as 44 and the maximum number of CCEs to be received as 56 CCEs.

The terminal can receive PDCCH candidates in the search space until it reaches the maximum number of PDCCH candidates or the maximum number of CCEs to receive. If either the number of PDCCH candidates or the number of CCEs exceeds the maximum, the terminal will not receive (for example, this may be expressed as "dropping") any PDCCH candidates set in that search space.

Note that the number of PDCCH candidates and the number of CCEs are first counted for the common search space (CSS) and then for the UE-specific search space (UE-SS). In addition, if there are multiple UE-specific search spaces, the number of PDCCH candidates and the number of CCEs may be counted, for example, in the order of the search space IDs.

In SBFD symbols, the resources available for the PDCCH may differ. For example, it may not be possible to transmit or receive the PDCCH in the UL subband. For this reason, the resources available for the PDCCH (e.g., location and size) may differ between SBFD symbols and non-SBFD symbols. Therefore, there is room for consideration regarding how to allocate PDCCH resources in SBFD symbols and non-SBFD symbols.

In one non-limiting embodiment of the present disclosure, a method for allocating PDCCH resources in SBFD symbols and non-SBFD symbols is described.

[Communication System Overview]
A communication system according to an embodiment of the present disclosure may include, for example, a base station 100 (e.g., gNB) shown in Figures 2 and 4, and a terminal 200 (e.g., UE) shown in Figures 3 and 5. A plurality of base stations 100 and a plurality of terminals 200 may exist in the communication system.

FIG. 2 is a block diagram showing an example configuration of a portion of a base station 100 according to one embodiment of the present disclosure. In the base station 100 shown in FIG. 2, a control unit (e.g., corresponding to a control circuit) changes the resources of the control channel region (e.g., CORESET) when at least a portion of the resources of the control channel region is unavailable for a downlink control channel (e.g., PDCCH). A transmission unit (e.g., corresponding to a transmission circuit) transmits a signal of the downlink control channel in the resources of the control channel region.

FIG. 3 is a block diagram showing an example configuration of a portion of a terminal 200 according to one aspect of the present disclosure. In the terminal 200 shown in FIG. 3, a control unit (e.g., corresponding to a control circuit) changes the resources of the control channel region (e.g., CORESET) when at least a portion of the resources of the control channel region (e.g., PDCCH) is unavailable for the downlink control channel (e.g., PDCCH). A receiving unit (e.g., corresponding to a receiving circuit) receives a downlink control channel signal in the resources of the control channel region.

[Base station configuration]
4 is a block diagram showing a configuration example of a base station 100 according to an embodiment of the present disclosure. In FIG. 4, the base station 100 includes a receiving unit 101, a demapping unit 102, a demodulation and decoding unit 103, a scheduling unit 104, a resource control unit 105, a control information holding unit 106, a data and control information generating unit 107, an encoding and modulation unit 108, a mapping unit 109, and a transmitting unit 110.

Note that, for example, at least one of the demapping unit 102, demodulation/decoding unit 103, scheduling unit 104, resource control unit 105, control information storage unit 106, data/control information generation unit 107, coding/modulation unit 108, and mapping unit 109 may be included in the control unit shown in FIG. 2, and the transmission unit 110 may be included in the transmission unit shown in FIG. 2.

The receiving unit 101 performs reception processing, such as down-conversion or A/D conversion, on the received signal received via the antenna, and outputs the received signal after reception processing to the demapping unit 102.

The demapping unit 102 performs resource demapping on the received signal (e.g., an uplink signal) input from the receiving unit 101, and outputs the modulated signal to the demodulation and decoding unit 103.

The demodulation and decoding unit 103, for example, demodulates and decodes the modulated signal input from the demapping unit 102, and outputs the decoded result to the scheduling unit 104.

The scheduling unit 104 may, for example, perform scheduling for the terminals 200. The scheduling unit 104 schedules transmission and reception for each terminal 200 based on, for example, at least one of the decoding results input from the demodulation and decoding unit 103 and the control information input from the control information storage unit 106, and instructs the data and control information generation unit 107 to generate at least one of data and control information. The scheduling unit 104 may also output the scheduling information to the resource control unit 105. The scheduling unit 104 may also output control information related to scheduling for the terminals 200 to the control information storage unit 106.

The resource control unit 105 determines the resources to be used for PDCCH transmission based on the scheduling information input from the scheduling unit 104 and the control information input from the control information holding unit 106, and outputs resource allocation information to the mapping unit 109.

The control information holding unit 106 holds, for example, control information set for each terminal 200. The control information may include, for example, downlink data channel settings for each terminal 200 (for example, information related to SBFD or PDCCH). The control information holding unit 106 may output, for example, the held information to each component of the base station 100 (for example, the scheduling unit 104 and the resource control unit 105) as necessary.

The data and control information generating unit 107 generates at least one of data and control information, for example, according to instructions from the scheduling unit 104, and outputs a signal including the generated data or control information to the coding and modulation unit 108.

The encoding and modulation unit 108 encodes and modulates, for example, the signal (e.g., data, control information) input from the data and control information generation unit 107, and outputs the modulated signal to the transmission unit 110.

The mapping unit 109 performs resource mapping of the modulated signal input from the coding and modulation unit 108 based on, for example, resource allocation information input from the resource control unit 105, and outputs the transmission signal to the transmission unit 110.

The transmitting unit 110 performs transmission processing such as D/A conversion, up-conversion, or amplification on the signal input from the mapping unit 109, and transmits the radio signal obtained by the transmission processing from the antenna to the terminal 200.

[Device configuration]
Fig. 5 is a block diagram showing a configuration example of a terminal 200 according to an aspect of the present disclosure. In Fig. 5, the terminal 200 includes a receiving unit 201, a demapping unit 202, a demodulation and decoding unit 203, a resource determining unit 204, a control unit 205, a control information holding unit 206, a data and control information generating unit 207, an encoding and modulation unit 208, a mapping unit 209, and a transmitting unit 210.

Note that, for example, at least one of the demapping unit 202, demodulation/decoding unit 203, resource determination unit 204, control unit 205, control information storage unit 206, data/control information generation unit 207, coding/modulation unit 208, and mapping unit 209 may be included in the control unit shown in FIG. 3, and the receiving unit 201 may be included in the receiving unit shown in FIG. 3.

The receiving unit 201 performs reception processing, such as down-conversion or A/D conversion, on the received signal received via the antenna, and outputs the received signal after reception processing to the demapping unit 202.

The demapping unit 202 performs resource demapping on the received signal input from the receiving unit 201 based on, for example, resource allocation information input from the resource determination unit 204, and outputs the modulated signal to the demodulation and decoding unit 203.

The demodulation and decoding unit 203, for example, demodulates and decodes the modulated signal input from the demapping unit 202, and outputs the decoded result to the resource determination unit 204 and the control unit 205. The decoded result may include, for example, at least one of upper layer signaling information and downlink control information.

The resource determination unit 204 determines the allocated resources based on, for example, the control information input from the control information storage unit 206 or instructions from the control unit 205, and outputs the resource allocation information to the demapping unit 202.

The control unit 205 may determine whether data or control information is to be transmitted or received, for example, based on the decoding result (e.g., data or control information) input from the demodulation and decoding unit 203 and the control information (e.g., control information related to SBFD or PDCCH) input from the control information storage unit 206. For example, if the determination result indicates that data or control information is to be transmitted, the control unit 205 may instruct the data and control information generation unit 207 to generate at least one of data and control information. Furthermore, the control unit 205 may instruct the resource determination unit 204 to make a resource determination for receiving the PDCCH, for example.

The control information storage unit 206 stores, for example, control information input from the control unit 205, and outputs the stored information to each component (for example, the resource determination unit 204 and the control unit 205) as necessary.

The data and control information generating unit 207 generates data or control information, for example, according to instructions from the control unit 205, and outputs a signal including the generated data or control information to the coding and modulation unit 208.

The encoding and modulation unit 208, for example, encodes and modulates the signal input from the data and control information generation unit 207, and outputs the modulated signal to the mapping unit 209.

The mapping unit 209 performs resource mapping on the modulated signal input from the coding and modulation unit 208, and outputs the transmission signal to the transmission unit 210.

The transmitter 210 performs transmission processing such as D/A conversion, up-conversion, or amplification on the signal input from the mapping unit 209, and transmits the radio signal obtained by the transmission processing from the antenna to the base station 100.

[Operations of base station 100 and terminal 200]
An example of the operation of base station 100 and terminal 200 having the above configuration will be described.

FIG. 6 is a sequence diagram showing an example of the operation of the base station 100 and the terminal 200.

In FIG. 6, the base station 100 determines, for example, settings (configuration) related to SBFD or PDCCH (S101).

The base station 100 transmits, for example, upper layer signaling information including the determined configuration information to the terminal 200 (S102).

The terminal 200 determines the time and/or frequency resources (e.g., also called time and frequency resources) for receiving the PDCCH based on, for example, configuration information included in the signaling information transmitted from the base station 100 (S103).

The base station 100 transmits a downlink control signal (e.g., PDCCH) based on, for example, the configuration information and scheduling for the terminal 200 (S104).

[Resource Allocation Method]
A resource allocation method in the base station 100 (e.g., the resource control unit 105) will be described. Note that the terminal 200 (e.g., the resource determination unit 204) may determine the allocated resources assuming the resource allocation method implemented by the base station 100.

Any of the following conditions may be assumed as conditions under which PDCCH resources can be allocated to terminal 200.

＜Condition A＞
When all time/frequency resources in the CORESET are available for the PDCCH, the PDCCH candidates in the CORESET are available. For example, in order to use the CORESET (and the PDCCH candidates in the CORESET), it is necessary to make all time/frequency resources in the CORESET available.

＜Condition B＞
When all the time and frequency resources of the PDCCH candidate are available resources, the PDCCH candidate is available. For example, to use the PDCCH candidate, all the resources of the CORESET do not need to be available resources, but the resources of the PDCCH candidate to be transmitted and received need to be available resources.

＜Condition C＞
When even a part of the time/frequency resources of the PDCCH candidate is available, the PDCCH candidate can be used. For example, the PDCCH can be transmitted and received using some CCEs or resource element groups (REGs) among the resources of the PDCCH candidate.

Figure 7 shows examples of conditions under which the above-mentioned PDCCH resource allocation is possible.

The diagram on the left side of Figure 7 shows an example of resource configuration for CORESET and PDCCH candidates. In the example of Figure 7, three PDCCH candidates (PDCCH candidates #0, #1, #2) are configured within the resources of CORESET. Also, in the example of Figure 7, one DL subband (D) and one UL subband (U) are configured in the frequency domain where CORESERT is located.

In Condition A in Figure 7, the CORESET resources overlap with the UL subband, so the CORESET and all PDDCH candidates within the CORESET cannot be used.

In Condition B of Figure 7, the resources of PDCCH candidate#0 are included in the DL subband, so PDCCH candidate#0 is usable. On the other hand, at least some of the resources of PDCCH candidate#1 and PDCCH candidate#2 overlap with the UL subband, so PDCCH candidate#1 and PDCCH candidate#2 cannot be used.

In Condition C in Figure 7, at least some of the resources of PDCCH candidate#0 and PDCCH candidate#1 are included in the DL subband, so PDCCH candidate#0 and PDCCH candidate#1 are usable. On the other hand, the resources of PDCCH candidate#2 completely overlap with the UL subband, so PDCCHcandidate#2 cannot be used.

In the following, resources to which PDCCH resources can be assigned are defined as "available resources", and resources to which PDCCH resources cannot be assigned are defined as "unavailable resources". As mentioned above, the range of resources within the CORESET that are available for PDCCH differs depending on Condition A, B, or C. In addition, any one (or more) of the following criteria may be assumed when determining whether a resource is available or not.

<Judgment Criteria 1>
When the transmission direction of a resource is statically defined as DL, or semi-statically set as DL, the resource is determined as an available resource for the terminal 200. For example, the following cases are assumed.
- when statically defined as DL symbols or quasi-statically configured as DL symbols; - when statically defined as DL sub-bands or quasi-statically configured as DL sub-bands;

Criterion 1 allows for a static or quasi-static determination of whether a resource is available, simplifying the determination process.

<Judgment Criteria 2>
When the transmission direction of a resource is statically defined as Flexible (flexible, or the transmission direction is undetermined), or when the transmission direction is semi-statically set as Flexible, the resource is determined as an available resource for the terminal 200. For example, the following cases are assumed.
- When a symbol is statically defined as a Flexible symbol or semi-statically set as a Flexible symbol (if not explicitly set, it may be considered as Flexible).
- When a subband is statically defined as a Flexible subband or semi-statically set as a Flexible subband (Note that a subband whose transmission direction is not yet determined may be included. When not explicitly set, it may be considered as being undetermined. Resources on guard bands may be considered as Flexible. When DL reception is permitted in the UL subband, the UL subband may be considered as Flexible).

In addition, when the transmission direction is dynamically set, if a transmission direction other than DL (e.g., UL) is set, the resource may be determined to be an unavailable resource.

Criterion 2 allows flexibility in the resource transmission direction, improving resource utilization efficiency. In addition, in cases where the transmission direction is not dynamically set to UL, it becomes possible to statically or quasi-statically determine whether resources are available, simplifying the determination process.

<Judgment Criterion 3>
When the transmission direction of a resource is dynamically set to DL, the resource is determined as an available resource for the terminal 200. For example, the following cases are assumed.
- DL symbols or symbol transmission direction is dynamically configured as DL (e.g., slot format signaling by group common PDCCH, individual PDCCH signaling)
- When the transmission direction of a DL subband or RB (or RE) is dynamically set as DL (e.g., notification of the transmission direction of the subband by a group common PDCCH, notification by an individual PDCCH. If DL reception is permitted in the UL subband, the transmission direction may be considered as DL even in the UL subband by these notifications).

Criterion 3 allows for flexibility in the direction of resource transmission, improving resource utilization efficiency.

The above explains the criteria for evaluation.

The base station 100 and the terminal 200 may determine the PDCCH resource by combining these criteria. For example, if criterion 1, criterion 2, or criterion 3 is satisfied, the resource may be determined as available. For example, if the transmission direction of the resource is statically defined as DL or Flexible, semi-statically set as DL or Flexible, or dynamically set as DL, the base station 100 and the terminal 200 may determine that the resource is available.

Also, for example, the criteria to be applied among these criteria may be set semi-statically.

Below is an example of how to allocate resources.

<Method 1>
In method 1, base station 100 and terminal 200 change the size of the CORESET resources depending on the available resources for the PDCCH.

For example, in method 1, Condition A may be assumed. The base station 100 and the terminal 200 change the size of the CORESET, for example, so that all time and frequency resources of the CORESET become available resources.

For example, if the CORESET overlaps (or collides) with unavailable resources, the size of the CORESET may be reduced to the size of resources other than the unused resources. For example, if any resource element in one CCE contains an unavailable resource, that CCE is not used as a resource of the CORESET. Here, since CCEs are used as the processing unit of the PDCCH (e.g., setting the aggregation level, etc.), changing the size of the CORESET on a CCE-by-CCE basis (e.g., determining the CCE to use) can reduce the impact on the transmission and reception processing of the PDCCH.

Figure 8 shows an example of CORESET settings in method 1. In Figure 8, the vertical direction represents the frequency direction.

The left side of Figure 8 shows the CORESET resource configuration.

Case 1 in Figure 8 shows an example in which the reception timing (monitoring occasion) of the search space linked to the CORESET is set for a slot consisting of DL symbols. In Case 1, the CORESET resources are placed in the DL symbol, and since they are all available resources for the PDCCH, the set CORESET resources are used as is (the size is not changed).

Case 2 in Figure 8 shows an example in which the reception timing of the CORESET is set for a slot consisting of SBFD symbols. The subband configuration in Case 2 is {DUD}. In Case 2, CCEs that overlap with the UL subband are not used as the CORESET, and the CCEs on the DL subband are set as the CORESET resources. Thus, in Case 2, the size of the set CORESET resources is changed (e.g., reduced) to a size consisting of the CCEs on the DL subband.

In addition, in Case 2 in Figure 8, as an example, a case is assumed in which the boundaries of CCEs and the boundaries of subbands do not coincide, so part of the DL subband (CCEs whose resource elements are included in the UL subband) is not used as a resource for the CORESET.

In this way, in method 1, the base station 100 and the terminal 200 can transmit and receive DL control information according to the available resources, thereby improving resource utilization efficiency. Furthermore, in method 1, it is possible to allocate a control channel area to both SBFD symbols (e.g., Case 2) and non-SBFD symbols (e.g., Case 1). Furthermore, since the size of the CORESET resources changes depending on the frequency band configuration (subband configuration), it becomes possible to share the same CORESET configuration for SBFD symbols and non-SBFD symbols, thereby reducing signaling overhead or signaling complexity.

<Method 2>
In method 2, base station 100 and terminal 200 change the location of resources in CORESET according to available resources for PDCCH.

For example, in method 2, Condition A may be assumed. The base station 100 and the terminal 200 change the position of the CORESET so that, for example, all time and frequency resources of the CORESET become available resources.

For example, if the CORESET overlaps (or collides) with unavailable resources, the CORESET resources may be shifted (or moved) to the position of the available resources. For example, if any resource element in one CCE contains an unavailable resource, the CCE is not used as a resource of the CORESET. Here, the available resource to which the CORESET resources are shifted may be determined, for example, as follows:

Example 1:
The CORESET is moved in the frequency domain (in ascending or descending order, or when it is moved to one end of the band, it is moved to the other end), and the position where all the resources of the CORESET are first available is determined as the destination resource. The granularity of moving the CORESET may be RB or CCE, or other units. For example, in the case of CCE units, a position that matches the existing CORESET and resource settings can be determined. In Example 1, the position of the CORESET can be changed without additional configuration (or by adding little configuration), so that the signaling overhead can be reduced.

Example 2:
The CORESET is moved to a semi-statically set position. A plurality of destination positions (candidates) of the CORESET may be set. For example, the base station 100 may check whether all resources of the CORESET are available from the candidate positions with high priority, and if available, may determine the position as the destination of the CORESET. In addition, the destination position of the CORESET may be directly specified by the position of the RB (for example, the first PRB number of the CORESET), or may be specified by an offset value from the original position of the CORESET. As in Example 2, the destination position of the CORESET can be set more flexibly by using a setting value.

Figure 9 shows an example of CORESET settings in method 2. In Figure 9, the vertical direction represents the frequency direction.

The left side of Figure 9 shows the CORESET resource configuration.

Case 1 in Figure 9 shows an example in which the reception timing (monitoring occasion) of the search space linked to the CORESET is set for a slot consisting of DL symbols. In Case 1, the CORESET resources are placed in the DL symbol, and since they are all available resources for the PDCCH, the set CORESET resources are used as is (their positions are not changed).

Case 2 in Figure 9 shows an example in which the CORESET reception timing is set for a slot consisting of SBFD symbols. The subband configuration in Case 2 is {UD}. In Case 2, the set CORESET resource overlaps with the UL subband, so the position of the CORESET resource is changed (or moved, shifted) to the position of the DL subband.

In this way, in method 2, the base station 100 and the terminal 200 can transmit and receive DL control information according to the available resources, thereby improving resource utilization efficiency. Furthermore, in method 2, it is possible to allocate a control channel area to both SBFD symbols (e.g., Case 2) and non-SBFD symbols (e.g., Case 1). Furthermore, since the position of the CORESET resources is changed according to the frequency band configuration (subband configuration), it becomes possible to share the same CORESET configuration for SBFD symbols and non-SBFD symbols, thereby reducing signaling overhead or signaling complexity.

<Method 3>
In method 3, base station 100 and terminal 200 set (or change) the reception timing of the PDCCH in terminal 200 according to available resources for the PDCCH.

For example, in method 3, Condition A may be assumed. The base station 100 and the terminal 200 may set the timing (monitoring occasion) for receiving the PDCCH of the terminal 200, for example, so that all time and frequency resources of the CORESET become available resources.

Here, a bitmap may be used to set the monitoring occasion. For example, when a bit in the bitmap is set to "1", the monitoring occasion is considered to be valid. For example, the terminal 200 receives the CORESET (and the PDCCH included in the CORESET) in the slot corresponding to the bitmap bit "1". Also, when a bit in the bitmap is set to "0", the monitoring occasion is considered to be invalid. For example, the terminal 200 does not receive the CORESET (and the PDCCH included in the CORESET) in the slot corresponding to the bitmap bit "0".

In this way, by using the bitmap, the base station 100 can flexibly set the monitoring occasion. For example, even if the SBFD symbols are not assigned periodically (e.g., every 1 ms), the base station 100 can set the monitoring occasion for any SBFD symbol. The bitmap may be notified (or set) to the terminal 200 by a parameter similar to "monitoringSlotPeriodicityAndOffset" in the "SearchSpace" IE (Information Element), for example.

In addition, the bitmap length (corresponding to the number of slots to be set) may be set as in any of the following examples.
Example 1: Fixed period (e.g., 1 frame (10 ms). If the subcarrier spacing is 15 kHz, the bitmap is 10 bits)
Example 2: Semi-statically set period Example 3: Period for which SBFD slots/symbols are set (for example, if the arrangement of SBFD slots/symbols is set at a period of 5 ms, the monitoring occasion setting may also be set to 5 ms)

Note that the bitmap is not limited to a slot-based bitmap, and the time resource unit corresponding to each bit of the bitmap may be another resource unit. For example, a symbol-based bitmap or a multiple-symbol-based bitmap (e.g., 7-symbol-based bitmap) may be used.

Figure 10 shows an example of CORESET settings in method 3. In Figure 10, the vertical axis represents the frequency direction, and the horizontal axis represents the time direction.

In the example of Figure 10, the monitoring occasion corresponding to one CORESET is set with a 10-bit bitmap (bits #0 to #9). The 10-bit bitmap corresponds to 10 slots (slots #0 to #9 in Figure 10). Also, in Figure 10, the subband configuration in the SBFD symbol is {DUD}, and the CORESET to be set may be set according to the frequency resource (subband configuration) of the SBFD symbol. As shown in Figure 10, the resources of the CORESET are set to include resources in the DL subband and not to include the UL subband (for example, to satisfy Condition A).

In the example of Figure 10, bits #1, #2, #3, #6, #7, and #8 in the bitmap are set to "1", and bits #0, #4, #5, and #9 are set to "0". Therefore, the monitoring occasion is enabled in slots #1, #2, #3, #6, #7, and #8 corresponding to bit "1", and terminal 200 receives the PDCCH. Furthermore, the monitoring occasion is disabled in slots #0, #4, #5, and #9 corresponding to bit "0", and terminal 200 does not receive the PDCCH.

Note that, although not shown in the example of Figure 10, a CORESET for a DL symbol (e.g., one of the non-SBFD symbols) and a monitoring occasion corresponding to that CORESET may be separately configured. In the example of Figure 10, the monitoring occasion corresponding to the CORESET for the DL symbol may have the bits corresponding to Slot #0 and #5 set to "1". This allows the monitoring occasion to be flexibly configured according to the configuration of the SBFD symbols and non-SBFD symbols, making it possible to configure different resources for the SBFD symbols and non-SBFD symbols.

In this way, in method 3, the base station 100 and the terminal 200 can transmit and receive DL control information according to the available resources, thereby improving resource utilization efficiency. Furthermore, in method 3, it is possible to allocate a control channel area to both SBFD symbols and non-SBFD symbols. Furthermore, in method 3, CORESET resource setting can be realized by changing the reception timing of the PDCCH by the terminal 200, so the impact on specifications is smaller than with other methods.

<Method 4>
In method 4, base station 100 and terminal 200 configure multiple CORESETs and search spaces according to available resources. For example, base station 100 and terminal 200 may configure (or select) one candidate according to available resources for PDCCH from multiple candidates for at least one of the resources of CORESET and the search space included in CORESET.

For example, in method 4, Condition A may be assumed. The base station 100 and the terminal 200 determine multiple CORESETs and search spaces, for example, so that all time and frequency resources of the CORESET are available resources.

For example, the base station 100 and the terminal 200 may determine whether or not to use a CORESET depending on whether the resource to which a CORESET is set is an available resource among multiple CORESETs. For example, multiple CORESETs may be linked to a search space. The base station 100 and the terminal 200 determine an available CORESET at the reception timing (monitoring occasion) of the search space. For example, the order in which multiple CORESETs are determined may be determined based on the priority set in the CORESET, or may be determined in the order of the CORESET IDs. This allows the base station 100 and the terminal 200 to flexibly select a CORESET to use depending on the resources.

Alternatively, a CORESET may be linked to whether it is placed in a symbol including unavailable resources (e.g., a CORESET placed in an SBFD symbol) or a CORESET placed in a symbol consisting of only available resources (e.g., a CORESET placed in a DL symbol). In this case as well, multiple CORESETs are linked to the search space, and base station 100 and terminal 200 determine whether or not to use each CORESET depending on the symbol (e.g., symbol type). This makes it possible to explicitly set the link between time/frequency resources (e.g., symbols) and CORESETs, making it easier to determine which CORESET to use.

Figure 11 shows an example of CORESET settings in method 4. In Figure 11, the vertical direction represents the frequency direction.

The left side of Figure 11 shows the configuration of CORESET resources. CORESET#1 is set as the CORESET placed in a symbol consisting of only available resources, and CORESET#2 is set as the CORESET placed in a symbol that includes unavailable resources.

In Case 1 in Figure 11, the reception timing (monitoring occasion) of the search space is set for a slot consisting of a DL symbol. In Case 1, since it is a DL symbol, CORESET#1 is set.

In Case 2 in Figure 11, the reception timing of the search space is set for a slot consisting of an SBFD symbol. In Case 2, the SBFD symbol contains UL resources, so CORESET#2 is set.

As shown in Figure 11, different CORESETs can be used for DL symbols and SBFD symbols.

In this way, in method 4, the base station 100 and the terminal 200 can transmit and receive DL control information according to the available resources, thereby improving resource utilization efficiency. Furthermore, in method 4, it is possible to allocate control channel areas to both SBFD symbols (e.g., Case 2) and non-SBFD symbols (e.g., Case 1). Furthermore, in method 4, it is possible to explicitly set a CORESET according to time and frequency resources, thereby improving the flexibility of resource allocation.

<Method 5>
In method 5, base station 100 and terminal 200 use different CORESETs and search spaces based on the maximum number of PDCCH candidates and the maximum number of CCEs to be received. For example, base station 100 and terminal 200 may set one of multiple CORESET candidates based on the number of PDCCH candidates (or the number of BDs) and the number of CCEs.

For example, in method 5, Condition A may be assumed. The base station 100 and the terminal 200 may set the CORESET and the search space based on the number of PDCCH candidates and the number of CCEs, for example, so that all time and frequency resources of the CORESET become available resources.

For example, if a CORESET overlaps with unavailable resources, base station 100 and terminal 200 do not use that CORESET and do not count the number of PDCCH candidates and CCEs of the search space linked to the CORESET. By not counting the number of PDCCH candidates and CCEs, terminal 200 can receive CORESETs (or PDCCHs) linked to other search spaces until the maximum number of PDCCH candidates or maximum number of CCEs is reached.

Figure 12 shows an example of CORESET settings in method 5. In Figure 12, the vertical direction represents the frequency direction.

The left side of Figure 12 shows the resource configuration of CORESET. SS (search space) #1 is linked to CORESET#1, and SS#2 is linked to CORESET#2. The number of PDCCH candidates (or the number of BDs) for each of SS#1 and SS#2 is set to 44 (44 BDs). The reception timing (monitoring occasion) for SS#1 and SS#2 is set to the same. The maximum number of PDCCH candidates per slot and per serving cell is set to 44. For simplicity, the maximum number of CCEs is not taken into consideration.

In Case 1 of Figure 12, the reception timings of SS#1 and SS#2 are set for a slot consisting of DL symbols. In this case, since it is a DL symbol, either CORESET can be used from the resource perspective, but for example, SS#1 with the smallest SS ID and CORESET#1 linked to SS#1 are placed (resources are allocated). Here, when SS#1 is placed, the maximum number of PDCCH candidates, 44, is reached, so CORESET#2 is not placed.

Therefore, in Case 1, base station 100 transmits a PDCCH in CORESET#1, and terminal 200 receives a PDCCH candidate in CORESET#1.

In Case 2 of Figure 12, it is assumed that the reception timings of SS#1 and SS#2 are set for a slot consisting of an SBFD symbol. For example, the base station 100 and terminal 200 determine whether SS#1, which has a smaller SS ID, and CORESET#1 linked to SS#1 can be deployed. As shown in Figure 12, the resources of CORESET#1 overlap with the UL subband, so CORESET#1 cannot be deployed. At this time, the number of PDCCH candidates (and the number of CCEs) for SS#1 is not counted. At this point, the number of PDCCH candidates is 0, so the base station 100 and terminal 200 determine whether the next SS#2 and CORESET#2 linked to SS#2 can be deployed. The resources of CORESET#2 do not overlap with the UL subband and are included in the DL subband, so CORESET#2 can be deployed.

Therefore, in Case 2, base station 100 transmits a PDCCH in CORESET#2, and terminal 200 receives a PDCCH candidate in CORESET#2.

In this way, when a CORESET overlaps with unavailable resources, the base station 100 and the terminal 200 do not use the CORESET and do not count the number of PDCCH candidates and the number of CCEs in the search space linked to the CORESET. This makes it possible to place different CORESETs in DL symbols and SBFD symbols, for example.

In this way, in method 5, the base station 100 and the terminal 200 can transmit and receive DL control information according to the available resources, thereby improving resource utilization efficiency. Furthermore, in method 5, it is possible to allocate a control channel area to both SBFD symbols (e.g., Case 2) and non-SBFD symbols (e.g., Case 1). Furthermore, in method 5, the resources of the CORESET are not changed, so complexity can be reduced compared to, for example, method 1 or method 2 (methods that change the size or position of the CORESET). Furthermore, in method 5, no additional configuration is required, so signaling overhead or signaling-related complexity can be reduced.

<Method 6>
In method 6, base station 100 and terminal 200 change the PDCCH allocation candidate positions (positions of PDCCH candidates) included in CORESET according to available resources for the PDCCH.

For example, in method 6, Condition B may be assumed. The base station 100 and the terminal 200 change the PDCCH allocation candidate positions (positions of the PDCCH candidates) in the CORESET, for example, so that the resources of the PDCCH candidates to be transmitted and received become available resources.

For example, the base station 100 and the terminal 200 determine whether or not the resource for each PDCCH candidate is an available resource. The terminal 200 receives the set PDCCH candidate if, for example, all the CCEs/REGs that make up the PDCCH candidate are available resources. On the other hand, the terminal 200 does not receive (drops) the set PDCCH candidate if, for example, at least some of the CCEs/REGs that make up the PDCCH candidate are unavailable resources. When a PDCCH candidate is dropped, the base station 100 and the terminal 200 check whether the PDCCH candidate can be placed in another resource. If placement is possible, the base station 100 places the PDCCH candidate at that position and transmits the PDCCH, and the terminal 200 receives the PDCCH candidate placed at that position.

　を１ずつインクリメントして、配置可能なリソースであるか否かを確認し、配置可能な位置にPDCCH candidateを配置してよい。 For example, when changing the position of the PDCCH candidate, the base station 100 and the terminal 200 use a PDCCH candidate number that indicates the PDCCH candidate number when calculating the CCE in which the PDCCH candidate is placed.

may be incremented by one to check whether the resource is available for allocation, and the PDCCH candidate may be allocated to a position where it can be allocated.

Figure 13 shows an example of CORESET and PDCCH candidate settings in method 6. In Figure 13, the vertical axis represents the frequency direction.

The left side of Figure 13 shows the configuration of CORESET resources and PDCCH candidates. In the example of Figure 13, three PDCCH candidates (PDCCH candidate #0, #1, #2) are configured.

Case 1 in FIG. 13 shows an example in which changing the position of the PDCCH candidate according to unavailable resources (e.g., UL subband) is not applied. In Case 1, PDCCH candidate #2 is placed so as to overlap with the UL subband, so PDCCH candidate #2 is not placed. Terminal 200, for example, does not receive PDCCH candidate #2.

Case 2 in Figure 13 shows an example of applying a change in the position of a PDCCH candidate depending on unavailable resources. Because the position of the set PDCCH candidate #2 overlaps with the UL subband, the base station 100 and the terminal 200 shift (move) the PDCCH candidate #2 to a position where it can be placed.

　とした場合、この例では、

　の位置がDLサブバンド上に位置するため、PDCCH candidate#2が配置可能と判断される。 For example, in Case 2, the configured PDCCH candidate #2 is

In this example,

Since the position of PDCCH candidate#2 is located on the DL subband, it is determined that PDCCH candidate#2 can be placed.

As shown in FIG. 13, in Case 1, two PDCCH candidates are placed and one PDCCH candidate is not placed, whereas in Case 2, by changing the position of the PDCCH candidates, three PDCCH candidates are placed, thereby increasing the opportunities for receiving the PDCCH at terminal 200.

In this way, in method 6, the base station 100 and the terminal 200 can transmit and receive DL control information according to the available resources, thereby improving resource utilization efficiency. Furthermore, in method 6, it is possible to allocate a control channel area to both SBFD symbols and non-SBFD symbols. Furthermore, in method 6, the resources of the CORESET are not changed, so complexity can be reduced compared to methods that change the size of the CORESET.

<Method 7>
In method 7, base station 100 and terminal 200 change the transmission method of PDCCH signals in some available resources among resources allocated to PDCCHs included in CORESET. For example, when some of PDCCH allocation candidate positions (positions of PDCCH candidates) are available resources, base station 100 punctures CCEs or REGs that are not available resources.

For example, in method 7, Condition C may be assumed. The base station 100 and the terminal 200 transmit and receive the PDCCH, for example, using some of the CCEs or REGs that constitute the resources of the PDCCH candidate. The base station 100, for example, punctures the CCEs or REGs that correspond to unavailable resources among the CCEs or REGs that constitute the resources of the PDCCH candidate when transmitting the PDCCH. For example, the base station 100 does not need to resource map the modulated signal to the CCEs or REGs that correspond to unavailable resources. As a result, the base station 100 transmits the PDCCH using the remaining CCEs or REGs (for example, CCEs or REGs that are composed only of available resources), and the terminal 200 receives the PDCCH candidate using only the remaining CCEs or REGs.

Although the effective coding rate increases due to puncturing, there is a possibility that PDCCH reception (decoding) may be successful depending on the original coding rate or reception quality, etc. For example, by setting the original coding rate low (e.g., by setting the aggregation level high), it may be possible to satisfy the required coding rate for the reception quality even if puncturing is performed.

Furthermore, for example, reception quality can be improved by increasing the transmission power of the punctured PDCCH. Since subband boundaries and CCE boundaries do not necessarily coincide, puncturing on a REG basis increases the resources used for transmission more than puncturing on a CCE basis, and by suppressing increases in the coding rate, it is possible to improve the likelihood that terminal 200 will successfully receive the PDCCH.

Figure 14 shows an example of PDCCH candidate settings in method 7. In Figure 14, the vertical axis represents the frequency direction, and the horizontal axis represents the time direction.

In Figure 14, RB#0 to RB#17 form the DL subband, RB#18 to RB#20 form the guard band, and RB#21 to RB#26 form the UL subband. In addition, the CORESET is set across the DL subband, guard band, and UL subband, and PDCCH candidate#1 is assigned to CCE#4 to CCE#7.

As shown in FIG. 14, CCE#6 and CCE#7 are punctured because they overlap with the guard band and UL subband, respectively. Base station 100 transmits PDCCH using the remaining CCE#4 and CCE#5. Terminal 200 receives PDCCH candidate#1 using the remaining CCE#4 and CCE#5. As shown in FIG. 14, even if some resources become unavailable due to the guard band and UL subband, such as the SBFD symbol, base station 100 can transmit PDCCH using available resources.

In this way, in method 7, the base station 100 and the terminal 200 can transmit and receive DL control information according to the available resources, thereby improving resource utilization efficiency. Furthermore, in method 7, it is possible to allocate a control channel area to both SBFD symbols and non-SBFD symbols. Furthermore, in method 7, even if the resources to which the PDCCH can be allocated are limited, it is possible to transmit and receive the PDCCH, thereby improving the opportunity to receive the PDCCH and reducing delays.

In addition, in method 7, the PDCCH candidate is adjusted by puncturing, so this can be easily achieved by, for example, not allocating the PDCCH to resources other than the available resources when performing resource mapping after coding and rate matching.

<Method 8>
In method 8, the base station 100 and the terminal 200 change the transmission method of the PDCCH signal in some available resources among the resources allocated to the PDCCH included in the CORESET. For example, if some of the PDCCH allocation candidate positions (positions of the PDCCH candidates) are available resources, the base station 100 applies rate matching to the available resources.

For example, in method 8, Condition C may be assumed. The base station 100 and the terminal 200 transmit and receive the PDCCH, for example, using some of the CCEs or REGs that constitute the resources of the PDCCH candidate.

In method 8, instead of applying puncturing as in method 7, rate matching is applied to the remaining resources. Puncturing can cause bias in the coded bits to be transmitted (for example, coded bits corresponding to specific bits in the payload may not be sent due to puncturing), whereas applying rate matching can reduce bias, thereby improving reception performance.

For example, when rate matching is applied on a REG basis, the resources used for transmission are increased, similar to puncturing, and the increase in the coding rate can be suppressed. Also, since existing coding and rate matching processes are based on CCE, applying rate matching on a CCE basis can reduce the complexity of the process.

In this way, in method 8, the base station 100 and the terminal 200 can transmit and receive DL control information in accordance with the available resources, thereby improving resource utilization efficiency. Furthermore, in method 8, it is possible to allocate a control channel area to both SBFD symbols and non-SBFD symbols. Furthermore, in method 8, even if the resources to which the PDCCH can be allocated are limited, it is possible to transmit and receive the PDCCH, thereby improving the opportunity to receive the PDCCH and reducing delays. Furthermore, rate matching can reduce the possibility of bias in bits after encoding, thereby improving reception performance compared to puncturing.

　Above, methods 1 to 8 for resource allocation have been explained.

Methods 1 to 8 may be applied in combination. For example, methods 1 and 2 may be combined to change the size and position of the CORESET.

In this manner, in this embodiment, the base station 100 and the terminal 200 change the resources of the CORESET (or the PDCCH candidate included in the CORESET) when at least a portion of the resources of the CORESET cannot be used for the PDCCH. As a result, even when the available resources for the PDCCH may differ, such as for the SBFD symbol, the base station 100 and the terminal 200 can transmit and receive the PDCCH by changing the resources of the CORESET or the PDCCH candidate according to the unavailable resources. Thus, according to this embodiment, resource allocation in wireless communication can be appropriately controlled.

Other Embodiments
[Differences in operation depending on the type of device]
The operation may differ between a terminal 200 that supports SBFD (e.g., also referred to as an SBFD aware UE or an SBFD capable UE) and a terminal 200 that does not support SBFD (e.g., also referred to as a Non-SBFD aware UE or an Non-SBFD capable UE).

For example, in Condition A, a terminal 200 that supports SBFD may receive a PDCCH candidate in the CORESET, assuming that the resources of the CORESET have been changed (e.g., assuming that any or more of method 1, method 2, method 3, method 4, and method 5 have been applied). On the other hand, a terminal 200 that does not support SBFD may receive a PDCCH candidate in the original CORESET (e.g., a CORESET to which the above methods are not applied).

Furthermore, for example, in Condition B, a terminal 200 that supports SBFD may receive a PDCCH candidate in the CORESET, assuming that the position of the PDCCH candidate in the CORESET has been changed (e.g., assuming that method 6 has been applied). On the other hand, a terminal 200 that does not support SBFD may receive a PDCCH candidate in the original CORESET (e.g., a CORESET to which the above method is not applied).

Furthermore, for example, in Condition C, a terminal 200 that supports SBFD may receive a PDCCH candidate in the CORESET, assuming that the resources of the CORESET have been changed (e.g., assuming that either method 7 or method 8 has been applied). On the other hand, a terminal 200 that does not support SBFD may receive a PDCCH candidate in the original CORESET (e.g., a CORESET to which the above methods are not applied).

[Application of Condition A]
Whether or not to apply a method assuming Condition A (eg, Method 1, Method 2, Method 3, Method 4, Method 5) may be determined based on, for example, the number of PDCCH candidates overlapping with unavailable resources.

For example, assume that the threshold for the number of PDCCH candidates is N. If the number of PDCCH candidates that overlap with unavailable resources is N or less, the method assuming Condition A does not need to be applied. In this case, the method assuming Condition B (Method 6) or the method assuming Condition C (Methods 7 and 8) may be applied.

Also, for example, if there are more than N PDCCH candidates that overlap with unavailable resources, a method assuming Condition A may be applied (for example, in the case of Method 1, the size of the CORESET is changed).

N may be set semi-statically or dynamically, or may be defined in a standard. In addition, the criterion for determining whether to apply Condition A may be a percentage instead of the number of PDCCH candidates that overlap with unavailable resources. For example, when more than 50% of the PDCCH candidate resources are unavailable among the PDCCHs set in terminal 200, a method assuming Condition A may be applied.

The method assuming Condition A involves changes to the size of the CORESET, which can complicate sending and receiving operations, but by applying it after making the above judgments (for example, by not always applying the method assuming Condition A), it is possible to reduce this complexity.

The above explains the application of Condition A.

In addition, in the above embodiment, a case where SBFD is applied has been described, but as long as the transmission direction (e.g., DL or UL) is set in multiple bands (e.g., subbands) into which a frequency band is divided, an embodiment of the present disclosure may be applied in a manner other than SBFD.

In addition, in the above-described embodiment, values such as the number of subbands, the number of DL subbands, the number of UL subbands, the number of guard bands, the number of PRBs, the number of slots, the number of CCEs, and the number of REGs are merely examples and are not limited to these. In addition, the subband configuration (e.g., {DUD}) used in the above-described embodiment is merely an example, and the number of subbands and the arrangement order of the DL subbands and UL subbands are not limited to these.

In addition, although the above-described embodiment has been described with reference to a downlink control channel (PDCCH), the present disclosure is not limited thereto. For example, the above-described embodiment may be applied to other downlink channels or signals different from the PDCCH, or channels or signals in different transmission directions, such as an uplink or sidelink.

(supplement)
Information indicating whether terminal 200 supports the functions, operations or processes described in the above-mentioned embodiments may be transmitted (or notified) from terminal 200 to base station 100, for example, as capability information or capability parameters of terminal 200.

The capability information may include information elements (IEs) that individually indicate whether the terminal 200 supports at least one of the functions, operations, or processes shown in the above-described embodiments. Alternatively, the capability information may include information elements that indicate whether the terminal 200 supports a combination of any two or more of the functions, operations, or processes shown in the above-described embodiments.

Based on the capability information received from the terminal 200, the base station 100 may, for example, determine (or decide or assume) the functions, operations, or processing that are supported (or not supported) by the terminal 200 that transmitted the capability information. The base station 100 may perform operations, processing, or control according to the results of the determination based on the capability information. For example, the base station 100 may control resource allocation to the terminal 200 based on the capability information received from the terminal 200.

Note that the fact that the terminal 200 does not support some of the functions, operations, or processes described in the above-described embodiment may be interpreted as meaning that such some of the functions, operations, or processes are restricted in the terminal 200. For example, information or requests regarding such restrictions may be notified to the base station 100.

The information regarding the capabilities or limitations of the terminal 200 may be defined in a standard, for example, or may be implicitly notified to the base station 100 in association with information already known at the base station 100 or information transmitted to the base station 100.

(Control Signal)
In the present disclosure, a downlink control signal (or downlink control information) related to an embodiment of the present disclosure may be, for example, a signal (or information) transmitted in a Physical Downlink Control Channel (PDCCH) in a physical layer, or a signal (or information) transmitted in a Medium Access Control Control Element (MAC CE) or Radio Resource Control (RRC) in a higher layer. In addition, the signal (or information) is not limited to being notified by a downlink control signal, and may be predefined in a specification (or standard), or may be preconfigured in a base station and a terminal.

In the present disclosure, the uplink control signal (or uplink control information) related to one embodiment of the present disclosure may be, for example, a signal (or information) transmitted in a PUCCH in the physical layer, or a signal (or information) transmitted in a MAC CE or RRC in a higher layer. Furthermore, the signal (or information) is not limited to being notified by an uplink control signal, but may be predefined in a specification (or standard), or may be preconfigured in a base station and a terminal. Furthermore, the uplink control signal may be replaced with, for example, uplink control information (UCI), 1st stage sidelink control information (SCI), or 2nd stage SCI.

(Base station)
In an embodiment of the present disclosure, the base station may be a Transmission Reception Point (TRP), a cluster head, an access point, a Remote Radio Head (RRH), an eNodeB (eNB), a gNodeB (gNB), a Base Station (BS), a Base Transceiver Station (BTS), a parent device, a gateway, or the like. In addition, in sidelink communication, a terminal may play the role of a base station. In addition, instead of a base station, a relay device that relays communication between an upper node and a terminal may be used. Also, a roadside unit may be used.

(Uplink/Downlink/Sidelink)
An embodiment of the present disclosure may be applied to, for example, any of an uplink, a downlink, and a sidelink. For example, an embodiment of the present disclosure may be applied to a Physical Uplink Shared Channel (PUSCH), a Physical Uplink Control Channel (PUCCH), a Physical Random Access Channel (PRACH) in the uplink, a Physical Downlink Shared Channel (PDSCH), a PDCCH, a Physical Broadcast Channel (PBCH) in the downlink, or a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Control Channel (PSCCH), or a Physical Sidelink Broadcast Channel (PSBCH) in the sidelink.

Note that PDCCH, PDSCH, PUSCH, and PUCCH are examples of a downlink control channel, a downlink data channel, an uplink data channel, and an uplink control channel, respectively. Also, PSCCH and PSSCH are examples of a sidelink control channel and a sidelink data channel. Also, PBCH and PSBCH are examples of a broadcast channel, and PRACH is an example of a random access channel.

(Data Channel/Control Channel)
An embodiment of the present disclosure may be applied to, for example, any of a data channel and a control channel. For example, the channel in an embodiment of the present disclosure may be replaced with any of the data channels PDSCH, PUSCH, and PSSCH, or the control channels PDCCH, PUCCH, PBCH, PSCCH, and PSBCH.

(Reference signal)
In one embodiment of the present disclosure, the reference signal is, for example, a signal known by both the base station and the mobile station, and may be called a Reference Signal (RS) or a pilot signal. The reference signal may be any of a Demodulation Reference Signal (DMRS), a Channel State Information - Reference Signal (CSI-RS), a Tracking Reference Signal (TRS), a Phase Tracking Reference Signal (PTRS), a Cell-specific Reference Signal (CRS), or a Sounding Reference Signal (SRS).

(Time Interval)
In an embodiment of the present disclosure, the unit of time resource is not limited to one or a combination of slots and symbols, but may be, for example, a time resource unit such as a frame, a superframe, a subframe, a slot, a time slot, a subslot, a minislot, a symbol, an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a Single Carrier-Frequency Division Multiplexing Access (SC-FDMA) symbol, or another time resource unit. In addition, the number of symbols included in one slot is not limited to the number of symbols exemplified in the above embodiment, and may be another number of symbols.

(Frequency Band)
An embodiment of the present disclosure may be applied to either a licensed band or an unlicensed band.

(communication)
An embodiment of the present disclosure may be applied to any of communication between a base station and a terminal (Uu link communication), communication between terminals (Sidelink communication), and Vehicle to Everything (V2X) communication. For example, the channel in an embodiment of the present disclosure may be replaced with any of PSCCH, PSSCH, Physical Sidelink Feedback Channel (PSFCH), PSBCH, PDCCH, PUCCH, PDSCH, PUSCH, and PBCH.

Furthermore, an embodiment of the present disclosure may be applied to either a terrestrial network or a non-terrestrial network (NTN: Non-Terrestrial Network) using a satellite or a High Altitude Pseudo Satellite (HAPS: High Altitude Pseudo Satellite). Furthermore, an embodiment of the present disclosure may be applied to a terrestrial network in which the transmission delay is large compared to the symbol length or slot length, such as a network with a large cell size or an ultra-wideband transmission network.

(Antenna port)
In one embodiment of the present disclosure, an antenna port refers to a logical antenna (antenna group) consisting of one or more physical antennas. For example, an antenna port does not necessarily refer to one physical antenna, but may refer to an array antenna consisting of multiple antennas. For example, an antenna port may be defined as the minimum unit by which a terminal station can transmit a reference signal, without specifying how many physical antennas the antenna port is composed of. In addition, an antenna port may be defined as the minimum unit by which a weighting of a precoding vector is multiplied.

<5G NR system architecture and protocol stack>
3GPP continues to work on the next release of the fifth generation of mobile phone technology (also simply referred to as "5G"), which includes the development of a new radio access technology (NR) that will operate in the frequency range up to 100 GHz. The first version of the 5G standard was completed in late 2017, allowing the prototyping and commercial deployment of 5G NR compliant terminals (e.g., smartphones).

For example, the system architecture as a whole assumes an NG-RAN (Next Generation - Radio Access Network) comprising gNBs. The gNBs provide the UE-side termination of the NG radio access user plane (SDAP/PDCP/RLC/MAC/PHY) and control plane (RRC) protocols. The gNBs are connected to each other via an Xn interface. The gNBs are also connected to the Next Generation Core (NGC) via a Next Generation (NG) interface, more specifically to the Access and Mobility Management Function (AMF) (e.g., a specific core entity performing AMF) via an NG-C interface, and to the User Plane Function (UPF) (e.g., a specific core entity performing UPF) via an NG-U interface. The NG-RAN architecture is shown in Figure 15 (see, for example, 3GPP TS 38.300 v15.6.0, section 4).

The NR user plane protocol stack (see, for example, 3GPP TS 38.300, section 4.4.1) includes the PDCP (Packet Data Convergence Protocol (see, for example, TS 38.300, section 6.4)) sublayer, the RLC (Radio Link Control (see, for example, TS 38.300, section 6.3)) sublayer, and the MAC (Medium Access Control (see, for example, TS 38.300, section 6.2)) sublayer, which are terminated on the network side at the gNB. A new Access Stratum (AS) sublayer (SDAP: Service Data Adaptation Protocol) is also introduced on top of PDCP (see, for example, 3GPP TS 38.300, section 6.5). A control plane protocol stack is also defined for NR (see, for example, TS 38.300, section 4.4.2). An overview of Layer 2 functions is given in clause 6 of TS 38.300. The functions of the PDCP sublayer, RLC sublayer, and MAC sublayer are listed in clauses 6.4, 6.3, and 6.2 of TS 38.300, respectively. The functions of the RRC layer are listed in clause 7 of TS 38.300.

For example, the Medium-Access-Control layer handles multiplexing of logical channels and scheduling and scheduling-related functions, including handling various numerologies.

For example, the physical layer (PHY) is responsible for coding, PHY HARQ processing, modulation, multi-antenna processing, and mapping of signals to appropriate physical time-frequency resources. The physical layer also handles the mapping of transport channels to physical channels. The physical layer provides services to the MAC layer in the form of transport channels. A physical channel corresponds to a set of time-frequency resources used for the transmission of a particular transport channel, and each transport channel is mapped to a corresponding physical channel. For example, the physical channels include the PRACH (Physical Random Access Channel), PUSCH (Physical Uplink Shared Channel), and PUCCH (Physical Uplink Control Channel) as uplink physical channels, and the PDSCH (Physical Downlink Shared Channel), PDCCH (Physical Downlink Control Channel), and PBCH (Physical Broadcast Channel) as downlink physical channels.

NR use cases/deployment scenarios may include enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), and massive machine type communication (mMTC), which have diverse requirements in terms of data rate, latency, and coverage. For example, eMBB is expected to support peak data rates (20 Gbps in the downlink and 10 Gbps in the uplink) and effective (user-experienced) data rates that are about three times higher than the data rates offered by IMT-Advanced. On the other hand, for URLLC, stricter requirements are imposed on ultra-low latency (0.5 ms for user plane latency in UL and DL, respectively) and high reliability (1-10 ⁻⁵ within 1 ms). Finally, mMTC may require preferably high connection density (1,000,000 devices/km ² in urban environments), wide coverage in adverse environments, and extremely long battery life (15 years) for low-cost devices.

Therefore, OFDM numerology (e.g., subcarrier spacing, OFDM symbol length, cyclic prefix (CP) length, number of symbols per scheduling interval) suitable for one use case may not be valid for other use cases. For example, low latency services may preferably require a shorter symbol length (and therefore a larger subcarrier spacing) and/or fewer symbols per scheduling interval (also called TTI) than mMTC services. Furthermore, deployment scenarios with large channel delay spreads may preferably require a longer CP length than scenarios with short delay spreads. Subcarrier spacing may be optimized accordingly to maintain similar CP overhead. NR may support one or more subcarrier spacing values. Correspondingly, subcarrier spacings of 15 kHz, 30 kHz, 60 kHz... are currently considered. The symbol length Tu and subcarrier spacing Δf are directly related by the formula Δf = 1/Tu. Similar to LTE systems, the term "resource element" can be used to mean the smallest resource unit consisting of one subcarrier for the length of one OFDM/SC-FDMA symbol.

In the new wireless system 5G-NR, for each numerology and each carrier, a resource grid of subcarriers and OFDM symbols is defined for the uplink and downlink, respectively. Each element of the resource grid is called a resource element and is identified based on a frequency index in the frequency domain and a symbol position in the time domain (see 3GPP TS 38.211 v15.6.0).

<Functional separation between NG-RAN and 5GC in 5G NR>
Figure 16 shows the functional separation between NG-RAN and 5GC. The logical nodes of NG-RAN are gNB or ng-eNB. 5GC has logical nodes AMF, UPF, and SMF.

For example, gNBs and ng-eNBs host the following main functions:
- Radio Resource Management functions such as Radio Bearer Control, Radio Admission Control, Connection Mobility Control, dynamic allocation (scheduling) of resources to UEs in both uplink and downlink;
- IP header compression, encryption and integrity protection of the data;
- Selection of an AMF at UE attach time when routing to an AMF cannot be determined from information provided by the UE;
- Routing of user plane data towards the UPF;
- Routing of control plane information towards the AMF;
- Setting up and tearing down connections;
- scheduling and transmission of paging messages;
Scheduling and transmission of system broadcast information (AMF or Operation, Admission, Maintenance (OAM) origin);
- configuration of measurements and measurement reporting for mobility and scheduling;
- Transport level packet marking in the uplink;
- Session management;
- Support for network slicing;
- Management of QoS flows and mapping to data radio bearers;
- Support for UEs in RRC_INACTIVE state;
- NAS message delivery function;
- sharing of radio access networks;
- Dual connectivity;
- Close cooperation between NR and E-UTRA.

The Access and Mobility Management Function (AMF) hosts the following main functions:
– the ability to terminate Non-Access Stratum (NAS) signalling;
- NAS signalling security;
- Access Stratum (AS) security control;
- Core Network (CN) inter-node signaling for mobility between 3GPP access networks;
- Reachability to idle mode UEs (including control and execution of paging retransmissions);
- Managing the registration area;
- Support for intra-system and inter-system mobility;
- Access authentication;
- Access authorization, including checking roaming privileges;
- Mobility management control (subscription and policy);
- Support for network slicing;
– Selection of Session Management Function (SMF).

Additionally, the User Plane Function (UPF) hosts the following main functions:
- anchor point for intra/inter-RAT mobility (if applicable);
- external PDU (Protocol Data Unit) Session Points for interconnection with data networks;
- Packet routing and forwarding;
- Packet inspection and policy rule enforcement for the user plane part;
- Traffic usage reporting;
- an uplink classifier to support routing of traffic flows to the data network;
- Branching Point to support multi-homed PDU sessions;
QoS processing for the user plane (e.g. packet filtering, gating, UL/DL rate enforcement);
- Uplink traffic validation (mapping of SDF to QoS flows);
- Downlink packet buffering and downlink data notification triggering.

Finally, the Session Management Function (SMF) hosts the following main functions:
- Session management;
- Allocation and management of IP addresses for UEs;
- Selection and control of UPF;
- configuration of traffic steering in the User Plane Function (UPF) to route traffic to the appropriate destination;
- Control policy enforcement and QoS;
- Notification of downlink data.

<RRC connection setup and reconfiguration procedure>
Figure 17 shows some of the interactions between the UE, gNB, and AMF (5GC entities) when the UE transitions from RRC_IDLE to RRC_CONNECTED in the NAS portion (see TS 38.300 v15.6.0).

RRC is a higher layer signaling (protocol) used for UE and gNB configuration. With this transition, the AMF prepares UE context data (which includes, for example, PDU session context, security keys, UE Radio Capability, UE Security Capabilities, etc.) and sends it to the gNB with an INITIAL CONTEXT SETUP REQUEST. The gNB then activates AS security together with the UE. This is done by the gNB sending a SecurityModeCommand message to the UE and the UE responding with a SecurityModeComplete message to the gNB. The gNB then sends an RRCReconfiguration message to the UE, and upon receiving an RRCReconfigurationComplete from the UE, the gNB performs reconfiguration to set up Signaling Radio Bearer 2 (SRB2) and Data Radio Bearer (DRB). For signaling-only connections, the RRCReconfiguration steps are omitted, since SRB2 and DRB are not set up. Finally, the gNB notifies the AMF that the setup procedure is complete with an INITIAL CONTEXT SETUP RESPONSE.

Therefore, the present disclosure provides a 5th Generation Core (5GC) entity (e.g., AMF, SMF, etc.) comprising: a control circuit that, during operation, establishes a Next Generation (NG) connection with a gNodeB; and a transmitter that, during operation, transmits an initial context setup message to the gNodeB via the NG connection such that a signaling radio bearer between the gNodeB and a user equipment (UE) is set up. Specifically, the gNodeB transmits Radio Resource Control (RRC) signaling including a resource allocation configuration information element (IE) to the UE via the signaling radio bearer. The UE then transmits in the uplink or receives in the downlink based on the resource allocation configuration.

<IMT usage scenarios after 2020>
Figure 18 shows some of the use cases for 5G NR. The 3rd generation partnership project new radio (3GPP NR) considers three use cases that were envisioned by IMT-2020 to support a wide variety of services and applications. The first phase of specifications for enhanced mobile-broadband (eMBB) has been completed. Current and future work includes standardization for ultra-reliable and low-latency communications (URLLC) and massive machine-type communications (mMTC), in addition to expanding support for eMBB. Figure 18 shows some examples of envisioned usage scenarios for IMT beyond 2020 (see, for example, ITU-R M.2083 Figure 2).

The URLLC use cases have stringent requirements for performance such as throughput, latency, and availability. It is envisioned as one of the enabling technologies for future applications such as wireless control of industrial or manufacturing processes, remote medical surgery, automation of power transmission and distribution in smart grids, and road safety. URLLC's ultra-high reliability is supported by identifying technologies that meet the requirements set by TR 38.913. For NR URLLC in Release 15, key requirements include a target user plane latency of 0.5 ms for UL and 0.5 ms for DL. The overall URLLC requirement for a single packet transmission is a block error rate (BLER) of 1E-5 for a packet size of 32 bytes with a user plane latency of 1 ms.

From a physical layer perspective, reliability can be improved in many possible ways. Current room for reliability improvement includes defining a separate CQI table for URLLC, more compact DCI formats, PDCCH repetition, etc. However, this room can be expanded to achieve ultra-high reliability as NR becomes more stable and more developed (with respect to the key requirements of NR URLLC). Specific use cases for NR URLLC in Release 15 include Augmented Reality/Virtual Reality (AR/VR), e-health, e-safety, and mission-critical applications.

In addition, the technology enhancements targeted by NR URLLC aim to improve latency and reliability. Technology enhancements for improving latency include configurable numerology, non-slot-based scheduling with flexible mapping, grant-free (configured grant) uplink, slot-level repetition in data channel, and pre-emption in downlink. Pre-emption means that a transmission for which resources have already been allocated is stopped and the already allocated resources are used for other transmissions with lower latency/higher priority requirements that are requested later. Thus, a transmission that was already allowed is preempted by a later transmission. Pre-emption is applicable regardless of the specific service type. For example, a transmission of service type A (URLLC) may be preempted by a transmission of service type B (eMBB, etc.). Technology enhancements for improving reliability include a dedicated CQI/MCS table for a target BLER of 1E-5.

The mMTC (massive machine type communication) use case is characterized by a very large number of connected devices transmitting relatively small amounts of data that are typically not sensitive to latency. The devices are required to be low cost and have very long battery life. From an NR perspective, utilizing very narrow bandwidth portions is one solution that saves power from the UE's perspective and allows for long battery life.

As mentioned above, the scope of reliability improvement in NR is expected to be broader. One of the key requirements for all cases, e.g. for URLLC and mMTC, is high or ultra-high reliability. Several mechanisms can improve reliability from a radio perspective and a network perspective. In general, there are two to three key areas that can help improve reliability. These areas include compact control channel information, data channel/control channel repetition, and diversity in frequency, time, and/or spatial domains. These areas are generally applicable to reliability improvement regardless of the specific communication scenario.

For NR URLLC, further use cases with more stringent requirements are envisaged, such as factory automation, transportation and power distribution, with high reliability (up to ^10-6 level of reliability), high availability, packet size up to 256 bytes, time synchronization up to a few μs (depending on the use case, the value can be 1 μs or a few μs depending on the frequency range and low latency of the order of 0.5 ms to 1 ms (e.g. 0.5 ms latency on the targeted user plane).

Furthermore, for NR URLLC, there may be several technology enhancements from a physical layer perspective. These include PDCCH (Physical Downlink Control Channel) enhancements for compact DCI, PDCCH repetition, and increased monitoring of PDCCH. Also, UCI (Uplink Control Information) enhancements related to enhanced HARQ (Hybrid Automatic Repeat Request) and CSI feedback enhancements. There may also be PUSCH enhancements related to minislot level hopping, and retransmission/repetition enhancements. The term "minislot" refers to a Transmission Time Interval (TTI) that contains fewer symbols than a slot (a slot comprises 14 symbols).

<QoS Control>
The 5G Quality of Service (QoS) model is based on QoS flows and supports both QoS flows that require a guaranteed flow bit rate (GBR QoS flows) and QoS flows that do not require a guaranteed flow bit rate (non-GBR QoS flows). Thus, at the NAS level, QoS flows are the finest granularity of QoS partitioning in a PDU session. QoS flows are identified within a PDU session by a QoS Flow ID (QFI) carried in the encapsulation header over the NG-U interface.

For each UE, 5GC establishes one or more PDU sessions. For each UE, the NG-RAN establishes at least one Data Radio Bearer (DRB) for the PDU session, e.g. as shown above with reference to Figure 17. Additional DRBs for the QoS flows of that PDU session can be configured later (when it is up to the NG-RAN). The NG-RAN maps packets belonging to different PDU sessions to different DRBs. The NAS level packet filters in the UE and 5GC associate UL and DL packets with QoS flows, whereas the AS level mapping rules in the UE and NG-RAN associate UL and DL QoS flows with DRBs.

Figure 19 shows the non-roaming reference architecture for 5G NR (see TS 23.501 v16.1.0, section 4.23). An Application Function (AF) (e.g. an external application server hosting 5G services as illustrated in Figure 18) interacts with the 3GPP core network to provide services, e.g. accessing a Network Exposure Function (NEF) to support applications that affect traffic routing, or interacting with a policy framework for policy control (e.g. QoS control) (see Policy Control Function (PCF)). Based on the operator's deployment, Application Functions that are considered trusted by the operator can interact directly with the relevant Network Functions. Application Functions that are not allowed by the operator to access the Network Functions directly interact with the relevant Network Functions using an external exposure framework via the NEF.

Figure 19 further shows further functional units of the 5G architecture, namely Network Slice Selection Function (NSSF), Network Repository Function (NRF), Unified Data Management (UDM), Authentication Server Function (AUSF), Access and Mobility Management Function (AMF), Session Management Function (SMF), and Data Network (DN, e.g. operator provided services, Internet access, or third party provided services). All or part of the core network functions and application services may be deployed and run in a cloud computing environment.

Therefore, the present disclosure provides an application server (e.g., an AF in a 5G architecture) comprising: a transmitter that, in operation, transmits a request including QoS requirements for at least one of a URLLC service, an eMMB service, and an mMTC service to at least one of 5GC functions (e.g., a NEF, an AMF, an SMF, a PCF, an UPF, etc.) to establish a PDU session including a radio bearer between a gNodeB and a UE according to the QoS requirements; and a control circuit that, in operation, performs a service using the established PDU session.

The present disclosure can be realized by software, hardware, or software in conjunction with hardware. Each functional block used in the description of the above embodiments may be realized, in part or in whole, as an LSI, which is an integrated circuit, and each process described in the above embodiments may be controlled, in part or in whole, by one LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of one chip that contains some or all of the functional blocks. The LSI may have data input and output. Depending on the degree of integration, the LSI may be called an IC, system LSI, super LSI, or ultra LSI.

The integrated circuit method is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Also, a field programmable gate array (FPGA) that can be programmed after LSI manufacturing, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells inside the LSI, may be used. The present disclosure may be realized as digital processing or analog processing.

Furthermore, if an integrated circuit technology that can replace LSI appears due to advances in semiconductor technology or other derived technologies, it would be natural to use that technology to integrate functional blocks. The application of biotechnology, etc. is also a possibility.

The present disclosure may be implemented in any type of apparatus, device, or system (collectively referred to as a communications apparatus) having communications capabilities. The communications apparatus may include a radio transceiver and processing/control circuitry. The radio transceiver may include a receiver and a transmitter, or both as functions. The radio transceiver (transmitter and receiver) may include an RF (Radio Frequency) module and one or more antennas. The RF module may include an amplifier, an RF modulator/demodulator, or the like. Non-limiting examples of communication devices include telephones (e.g., cell phones, smartphones, etc.), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks, etc.), cameras (e.g., digital still/video cameras), digital players (e.g., digital audio/video players, etc.), wearable devices (e.g., wearable cameras, smartwatches, tracking devices, etc.), game consoles, digital book readers, telehealth/telemedicine devices, communication-enabled vehicles or mobile transport (e.g., cars, planes, ships, etc.), and combinations of the above-mentioned devices.

Communication devices are not limited to portable or mobile devices, but also include any type of equipment, device, or system that is non-portable or fixed, such as smart home devices (home appliances, lighting equipment, smart meters or measuring devices, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

Communications include data communication via cellular systems, wireless LAN systems, communication satellite systems, etc., as well as data communication via combinations of these.

The communication apparatus also includes devices such as controllers and sensors that are connected or coupled to a communication device that performs the communication functions described in this disclosure. For example, it includes controllers and sensors that generate control signals and data signals used by the communication device to perform the communication functions of the communication apparatus.

In addition, communication equipment includes infrastructure facilities, such as base stations, access points, and any other equipment, devices, or systems that communicate with or control the various non-limiting devices listed above.

A base station according to one embodiment of the present disclosure includes a control circuit that changes the resources of a control channel region when at least a portion of the resources of the control channel region is unavailable for a downlink control channel, and a transmission circuit that transmits a signal of the downlink control channel using the resources of the control channel region.

In one embodiment of the present disclosure, the control circuit changes the size of the resources in the control channel region depending on the resources available for the downlink control channel.

In one embodiment of the present disclosure, the control circuit changes the position of resources in the control channel region depending on the resources available for the downlink control channel.

In one embodiment of the present disclosure, the control circuit changes the reception timing of the signal at the terminal depending on the resources available for the downlink control channel.

In one embodiment of the present disclosure, the control circuit sets one candidate corresponding to resources available for the downlink control channel from among multiple candidates for at least one of the resources of the control channel region and the search space included in the control channel region.

In one embodiment of the present disclosure, the control circuit sets one of a plurality of candidates for the control channel region based on the number of blind decodings and the number of control channel elements (CCEs).

In one embodiment of the present disclosure, the control circuit changes the position of the allocation candidates for the downlink control channel included in the control channel region according to the resources available for the downlink control channel.

In one embodiment of the present disclosure, the control circuit changes the method of transmitting the signal in a portion of available resources among the resources allocated to the downlink control channel included in the control channel region.

In one embodiment of the present disclosure, the control circuit punctures control channel elements (CCEs) or resource element groups (REGs) of unavailable resources among the resources assigned to the downlink control channel.

In one embodiment of the present disclosure, the control circuit applies rate matching to available resources among the resources assigned to the downlink control channel.

A terminal according to one embodiment of the present disclosure includes a control circuit that changes the resources of a control channel region when at least a portion of the resources of the control channel region is unavailable for a downlink control channel, and a receiving circuit that receives a signal of the downlink control channel in the control channel region.

In a communication method according to one embodiment of the present disclosure, when at least a portion of the resources of a control channel region is unavailable for a downlink control channel, a base station changes the resources of the control channel region and transmits a signal of the downlink control channel in the control channel region.

In a communication method according to one embodiment of the present disclosure, when at least a portion of the resources of a control channel region is unavailable for a downlink control channel, a terminal changes the resources of the control channel region and receives a signal of the downlink control channel in the control channel region.

The entire disclosures of the specification, drawings and abstract contained in the Japanese application No. 2023-022528, filed on February 16, 2023, are incorporated herein by reference.

An embodiment of the present disclosure is useful in wireless communication systems.

100 Base station 101, 201 Receiving section 102, 202 Demapping section 103, 203 Demodulation and decoding section 104 Scheduling section 105 Resource control section 106, 206 Control information storage section 107, 207 Data and control information generation section 108, 208 Coding and modulation section 109, 209 Mapping section 110, 210 Transmitting section 200 Terminal 204 Resource determination section 205 Control section

Claims (13)

a control circuit for changing resources of a control channel region when at least a part of the resources of the control channel region is unavailable for a downlink control channel;
a transmission circuit for transmitting a signal of the downlink control channel in resources of the control channel region;
A base station comprising: the control circuit changes a size of the resource of the control channel region according to resources available for the downlink control channel.
The base station according to claim 1 . the control circuit changes a position of resources in the control channel region according to resources available for the downlink control channel.
The base station according to claim 1 . the control circuit changes a reception timing of the signal at the terminal in accordance with resources available for the downlink control channel.
The base station according to claim 1 . The control circuit sets one candidate according to resources available for the downlink control channel from among a plurality of candidates for at least one of the resources of the control channel region and the search space included in the control channel region.
The base station according to claim 1 . The control circuit sets one of a plurality of candidates for the control channel region based on the number of blind decodings and the number of control channel elements (CCEs).
The base station according to claim 1 . the control circuit changes a position of an allocation candidate of the downlink control channel included in the control channel region according to resources available for the downlink control channel.
The base station according to claim 1 . the control circuit changes a method of transmitting the signal in a part of available resources among resources allocated to the downlink control channel included in the control channel region;
The base station according to claim 1 . The control circuit punctures a control channel element (CCE) or a resource element group (REG) of an unavailable resource among resources assigned to the downlink control channel.
The base station according to claim 8. the control circuit applies rate matching to available resources among resources allocated to the downlink control channel.
The base station according to claim 8. a control circuit for changing resources of a control channel region when at least a part of the resources of the control channel region is unavailable for a downlink control channel;
a receiving circuit for receiving a signal of the downlink control channel in the control channel region;
A terminal comprising: The base station is
When at least a part of the resources of the control channel region is unavailable for the downlink control channel, modifying the resources of the control channel region;
Transmitting a signal of the downlink control channel in the control channel region.
Communication methods. The terminal is
When at least a part of the resources of the control channel region is unavailable for the downlink control channel, modifying the resources of the control channel region;
receiving a signal of the downlink control channel in the control channel region;
Communication methods.

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