User equipment, base station, communication method, and integrated circuit

Abstract

In the user equipment, the base station, the communication method, and the integrated circuit of the present application, the user equipment includes: circuitry configured to determine a physical uplink control channel (PUCCH) resource in a PUCCH resource set provided by cell-specific information, the cell-specific information being used to configure cell-specific PUCCH parameters for initial access; and at least one antenna configured to transmit acknowledgement (ACK) information using the PUCCH resource during the initial access. In the user equipment, the ACK information is transmitted using frequency hopping, and a frequency hopping pattern of the frequency hopping is a mirror pattern with a center of a frequency band used in a previous uplink transmission during the initial access as an axis.

Description

[0001] This application is a divisional application of Chinese invention patent application filed on January 12, 2018, with application number 201880084033.5, entitled "Base Station, Terminal and Communication Method", and filed by Panasonic Corporation (USA). Technical Field

[0002] This disclosure relates to base stations, terminals, and communication methods. Background Technology

[0003] With the recent widespread adoption of mobile broadband services, data traffic in mobile communications has increased exponentially. Therefore, expanding data transmission capacity for upcoming functionalities is considered an urgent task. Furthermore, the Internet of Things (IoT), which aims to connect all kinds of "things" via the internet, is expected to make significant strides in the coming years. To support the diversification of IoT services, substantial improvements are required not only in data transmission capacity but also in various aspects such as low latency and coverage. Against this backdrop, the technology development and standardization of fifth-generation mobile communication systems (5G) have been carried out, offering significant improvements in performance and characteristics compared to fourth-generation mobile communication systems (4G).

[0004] The 3rd Generation Partnership Project (3GPP) has been developing a new radio access technology (NR), which is not necessarily backward compatible with LTE in the 5G standard.

[0005] In NR, the terminal (UE: User Equipment) uses the uplink (UL) control channel (PUCCH: Physical Uplink Control Channel) to send response signals (ACK / NACK: Acknowledgment / Negative Acknowledgment) indicating the error detection results for downlink (DL) data, DL channel state information (CSI), and UL radio resource allocation request (SR: Scheduling Request) as in LTE (see, for example, non-patent literature (hereinafter referred to as "NPL") 1 and NPL 2 and 3).

[0006] The PUCCH resource parameters in NR, which have been standardized by 3GPP, include the symbol position in the time slot (hereinafter referred to as the in-slot symbol position), the number of symbols in the time slot (hereinafter referred to as the number of in-slot symbols), the frequency position, the on / off (enabled / disabled) state of the frequency hopping application, and code resources (such as cyclic shift sequences or orthogonal codes) (see NPL 3, for example). Terminals need to identify the parameters related to PUCCH resources in order to transmit the above information (ACK / NACK, CSI, or SR).

[0007] In NR, to identify the PUCCH resources used for transmitting ACK / NACK for DL ​​data, a method is employed where the base station indicates a semi-static PUCCH resource set via UE-specific higher-layer signals (e.g., Radio Resource Control (RRC) signaling) and indicates which PUCCH resource in the PUCCH resource set will actually be used via downlink control information (DCI) (e.g., see NPL 3). As described above, PUCCH resources include the symbol position within the time slot, the number of symbols within the time slot, the frequency position, the on / off state (enabled / disabled) of the frequency hopping application, and code resources (such as cyclic shift sequences or orthogonal codes).

[0008] Citation List

[0009] Non-patent literature

[0010] NPL 1

[0011] 3GPP TS 38.211V2.0.0, “NR; Physical channels and modulation (Version 15)”, December 2017

[0012] NPL 2

[0013] 3GPP TS 38.212V2.0.0, “NR; Multiplexing and channel coding (Version 15)”, December 2017

[0014] NPL 3

[0015] 3GPP TS 38.213V2.0.0, “NR; Physical layer procedure for control (Version 15)”, December 2017

[0016] NPL 4

[0017] RAN1#91, Chairman's Note, November 2017 Summary of the Invention

[0018] In NR, even during initial access, the terminal needs to identify parameters related to PUCCH resources in order to send ACK / NACK for message 4 during the Random Access Channel (RACH) process. As mentioned above, the method of using UE-specific higher-layer signals (RRC signaling) to identify PUCCH resources for sending ACK / NACK is effective for DL ​​data transmission after the RRC connection between the base station and the terminal is established; therefore, this method cannot be used during the initial access period before the RRC connection is established.

[0019] A non-limiting and exemplary embodiment helps to provide a base station, terminal, and communication method that can flexibly allocate PUCCH resources during initial access.

[0020] One aspect of the user equipment disclosed herein includes: circuitry for determining PUCCH resources in a physical uplink control channel (PUCCH) resource set provided by cell-specific information for configuring cell-specific PUCCH parameters for initial access; and at least one antenna for transmitting acknowledgment (ACK) information using the PUCCH resources during initial access, wherein frequency hopping is used to transmit the ACK information in a mirror pattern with the center of the frequency band used in previous uplink transmissions during the initial access period as the axis.

[0021] One aspect of this disclosure is a communication method for a user equipment, the communication method comprising: determining PUCCH resources in a physical uplink control channel (PUCCH) resource set provided by cell-specific information, the cell-specific information being used to configure cell-specific PUCCH parameters for initial access; and during initial access, using the PUCCH resources to send acknowledgment (ACK) information, wherein frequency hopping is used to send the ACK information, the frequency hopping pattern being a mirror pattern with the center of the frequency band used in previous uplink transmissions during the initial access as the axis.

[0022] One embodiment of the integrated circuit disclosed herein is used in a user equipment, the integrated circuit including control circuitry that controls the following processes: determining PUCCH resources in a physical uplink control channel (PUCCH) resource set provided by cell-specific information, the cell-specific information being used to configure cell-specific PUCCH parameters for initial access; and during initial access, using the PUCCH resources to send acknowledgment (ACK) information, wherein the ACK information is sent using frequency hopping, the frequency hopping pattern being a mirror pattern with the center of the frequency band used in previous uplink transmissions during the initial access as the axis.

[0023] One embodiment of the base station disclosed herein includes: at least one antenna that, during initial access, transmits cell-specific information for configuring cell-specific PUCCH parameters of a Physical Uplink Control Channel (PUCCH) resource set; and a receiving unit that receives acknowledgment (ACK) information transmitted using PUCCH resources in the PUCCH resource set, wherein the ACK information is transmitted using frequency hopping, the frequency hopping pattern being a mirror pattern with the center of the frequency band used in previous uplink transmissions during the initial access as the axis.

[0024] One aspect of the communication method disclosed herein is used for a base station, the communication method comprising: during initial access, transmitting cell-specific information for configuring cell-specific PUCCH parameters of a Physical Uplink Control Channel (PUCCH) resource set; and receiving acknowledgment (ACK) information transmitted using PUCCH resources in the PUCCH resource set, wherein the ACK information is transmitted using frequency hopping, the frequency hopping pattern being a mirror pattern with the center of the frequency band used in previous uplink transmissions during the initial access as the axis.

[0025] One embodiment of the integrated circuit disclosed herein is used in a base station. The integrated circuit includes control circuitry that controls the following processes: during initial access, transmitting cell-specific information for configuring cell-specific PUCCH parameters of a Physical Uplink Control Channel (PUCCH) resource set; and receiving acknowledgment (ACK) information transmitted using PUCCH resources in the PUCCH resource set, wherein the ACK information is transmitted using frequency hopping, the frequency hopping pattern being a mirror pattern with the center of the frequency band used in previous uplink transmissions during the initial access period as the axis.

[0026] In one general aspect, the technical features disclosed herein are: a base station comprising: circuitry for determining a set from a plurality of sets, wherein each set includes one or more candidates for resources used for an uplink (UL) control channel during initial access, and for determining a candidate from the one or more candidates included in the determined set; a transmitting unit for indicating the determined set to a terminal via higher-layer signaling and for indicating the determined candidate to the terminal via dynamic signaling; and a receiving unit for receiving UL control signals using resources corresponding to the determined candidate in the determined set, wherein an association between the value indicated by the higher-layer signaling and the plurality of sets is configured for each of one or more parameters relating to initial access.

[0027] On the other hand, the technical features disclosed herein are: a terminal comprising: a receiving unit that receives higher-layer signaling indicating any set among a plurality of sets, wherein each set includes one or more candidates for resources used for an uplink (UL) control channel during initial access, and receives dynamic signaling indicating any candidate among the one or more candidates in the set indicated by the higher-layer signaling; and a transmitting unit that transmits UL control signals using resources corresponding to the candidate indicated by the dynamic signaling among the one or more candidates included in the set indicated by the higher-layer signaling, wherein the value indicated by the higher-layer signaling is configured to associate with the plurality of sets for each of one or more parameters relating to initial access.

[0028] In yet another general aspect, the technology disclosed herein is characterized by: a communication method comprising: determining a set from a plurality of sets, wherein each set includes one or more candidates for resources used for an uplink (UL) control channel during initial access, and determining a candidate from the one or more candidates included in the determined set; indicating the determined set to a terminal via higher-layer signaling, and indicating the determined candidate to the terminal via dynamic signaling; and receiving UL control signals using resources corresponding to the determined candidate in the determined set, wherein the value indicated by the higher-layer signaling for each of the one or more parameters related to initial access is configured to be associated with the plurality of sets.

[0029] In yet another general aspect, the technology disclosed herein is characterized by: a communication method comprising: receiving higher-layer signaling indicating any set among a plurality of sets, wherein each set includes one or more candidates for resources used for an uplink (UL) control channel during initial access; and receiving dynamic signaling indicating any candidate among the one or more candidates for resources, the one or more candidates being included in the set indicated by the higher-layer signaling; and transmitting UL control signals using resources corresponding to the candidate indicated by the dynamic signaling among the one or more candidates included in the set indicated by the higher-layer signaling, wherein an association between the value indicated by the higher-layer signaling and the plurality of sets is configured for each of one or more parameters relating to initial access.

[0030] It should be noted that general or specific embodiments may be implemented as a system, apparatus, method, integrated circuit, computer program or storage medium, or any selective combination of system, apparatus, method, integrated circuit, computer program and storage medium.

[0031] According to one aspect of this disclosure, PUCCH resources can be flexibly allocated during initial access.

[0032] Other benefits and advantages of the disclosed embodiments will become apparent from the description and accompanying drawings. Benefits and / or advantages may be obtained individually from the various embodiments and features in the description and drawings, and it is not necessary to provide all of them to obtain one or more such benefits and / or advantages. Attached Figure Description

[0033] Figure 1 This is a block diagram illustrating a portion of the configuration of a base station according to Embodiment 1;

[0034] Figure 2 This is a block diagram illustrating a portion of the configuration of the terminal according to Embodiment 1;

[0035] Figure 3 This is a block diagram illustrating the configuration of a base station according to Embodiment 1;

[0036] Figure 4 This is a block diagram illustrating the configuration of the terminal according to Embodiment 1;

[0037] Figure 5 This is a timing diagram illustrating the processing of the base station and terminal according to Embodiment 1;

[0038] Figure 6A This is a diagram illustrating an example of the association between RMSI and the PUCCH resource set;

[0039] Figure 6B This is a diagram illustrating an example of the association between DCI and PUCCH resources;

[0040] Figure 6C This is a diagram illustrating an example of the parameters that form a PUCCH resource;

[0041] Figure 7A This is a diagram illustrating an example of the association between the RMSI and the PUCCH resource set according to Embodiment 1;

[0042] Figure 7B This is a diagram illustrating an example of the association between DCI and PUCCH resources of PUCCH format 0 according to embodiment 1;

[0043] Figure 7C This is a diagram illustrating an example of parameters for forming a PUCCH resource of PUCCH format 0 according to Embodiment 1;

[0044] Figure 7D This is a diagram illustrating an example of the association between DCI according to Embodiment 1 and PUCCH resources of PUCCH Format 1;

[0045] Figure 7E This is a diagram illustrating an example of parameters for forming a PUCCH resource of PUCCH format 1 according to embodiment 1;

[0046] Figure 8 This is a diagram illustrating the PUCCH format determination method according to Variation 1 of Example 1;

[0047] Figure 9 This is a diagram illustrating another method for determining the PUCCH format according to a variant of Example 1 of Embodiment 1;

[0048] Figure 10 This is a diagram illustrating an example of parameters for forming a PUCCH resource of PUCCH format 0 according to a variant of embodiment 1, example 2;

[0049] Figure 11 This is a diagram illustrating an example of parameters for forming a PUCCH resource of PUCCH format 1 according to a variant 2 of embodiment 1;

[0050] Figure 12 This is a diagram illustrating an example of parameters for forming a PUCCH resource of PUCCH format 0 according to a variant of embodiment 1, example 2;

[0051] Figure 13A This is a diagram illustrating an example of parameters for forming a PUCCH resource of PUCCH format 0 according to a variant of embodiment 1, example 2;

[0052] Figure 13B This is a diagram illustrating an example of parameters for forming a PUCCH resource of PUCCH format 1 according to a variant 2 of embodiment 1;

[0053] Figure 14A This is a diagram illustrating an example of parameters for forming a PUCCH resource of PUCCH format 0 according to a variant of embodiment 1, example 2;

[0054] Figure 14B This is a diagram illustrating an example of parameters for forming a PUCCH resource of PUCCH format 1 according to a variant 2 of embodiment 1;

[0055] Figure 15A This is a diagram illustrating an example of the association between the RMSI and the PUCCH resource set according to Embodiment 2;

[0056] Figure 15B This is a diagram illustrating an example of the association between the DCI and the PUCCH resource of resource 0 in message 1 (Msg.1) according to embodiment 2;

[0057] Figure 15C This is a diagram illustrating an example of the parameters of the PUCCH resource that forms resource 0 of message 1 according to embodiment 2;

[0058] Figure 15DThis is a diagram illustrating an example of the association between the DCI and the PUCCH resource of resource 1 in message 1 according to embodiment 2;

[0059] Figure 15E This is a diagram illustrating an example of the parameters of the PUCCH resource that forms resource 1 of message 1 according to embodiment 2;

[0060] Figure 16A This is a diagram illustrating other examples of the parameters of the PUCCH resource that forms resource 0 of message 1 according to embodiment 2;

[0061] Figure 16B This is a diagram illustrating other examples of the parameters of the PUCCH resource that forms resource 1 of message 1 according to embodiment 2;

[0062] Figure 17 This is a diagram illustrating the PUCCH format determination method according to a variant of Example 2;

[0063] Figure 18 This is a diagram illustrating another PUCCH format determination method according to a variant of Example 2;

[0064] Figure 19A This is a diagram illustrating an example of the association between the RMSI and the PUCCH resource set according to Embodiment 3;

[0065] Figure 19B This is a diagram illustrating an example of the association between the DCI and the PUCCH resource of resource 0 in message 3 according to embodiment 3;

[0066] Figure 19C This is a diagram illustrating other examples of parameters of the PUCCH resource that forms message 3 resource 0 according to embodiment 3;

[0067] Figure 19D This is a diagram illustrating an example of the association between the DCI and the PUCCH resource of resource 1 in message 3 according to embodiment 3;

[0068] Figure 19E This is a diagram illustrating an example of the parameters of the PUCCH resource that forms resource 1 of message 3 according to embodiment 3;

[0069] Figure 20A This is a diagram illustrating an example of the parameters of the PUCCH resource that forms resource 0 of message 3 according to embodiment 3; and

[0070] Figure 20B This is a diagram illustrating an example of the parameters of the PUCCH resource of resource 1 forming message 3 according to embodiment 3. Detailed Implementation

[0071] In the following detailed description of embodiments of the present disclosure, reference will be made to the accompanying drawings.

[0072] As mentioned earlier, in NR, the terminal needs to identify parameters related to PUCCH resources in order to send ACK / NACK for message 4 during the RACH process during initial access.

[0073] In NR, the base station indicates to the terminal the PUCCH resource set used to send ACK / NACK for message 4 via cell-specific or group-specific higher-layer signals (e.g., RMSI: Remaining Minimal System Information) (see NPL 3). Ideally, the RMSI overhead should be as small as possible at this time. For this purpose, in NR, the payload size used to indicate the PUCCH resource set in the RMSI has been set to 4 bits (e.g., see NPL 4).

[0074] In this regard, the relationship between the 4 bits (16 modes) in the RMSI and the PUCCH resource set used to send ACK / NACK for message 4 needs to be discussed in detail.

[0075] For example, for PUCCH resources used for ACK / NACK data transmission after the RRC connection is established, in order to identify the PUCCH resources, multiple parameters need to be configured for the symbol position in the time slot, the number of symbols in the time slot, the frequency position, the on / off state (enabled / disabled) of the frequency hopping application, and the code resources (such as cyclic shift sequences or orthogonal codes).

[0076] Furthermore, the configurable values ​​for each parameter related to the PUCCH resources used for ACK / NACK data transmission in DL after the RRC connection is established are wide-ranging. For the symbol position (start position) within a time slot, for example, 0 to 13 can be configured for a time slot consisting of 14 symbols. Furthermore, for the number of symbols within a time slot, 1 or 2 symbols can be configured for PUCCH format 0 (a short PUCCH capable of transmitting 1-bit or 2-bit response signals), and 4 to 14 symbols can be configured for PUCCH format 1 (a long PUCCH capable of transmitting 1-bit or 2-bit response signals). Additionally, the frequency position (PRB index) can be configured from 0 to 274. For frequency hopping applications, the on / off state (enabled / disabled) of the frequency hopping application can be configured. For code resources, cyclic shift sequence indices 0 to 11 can be configured for PUCCH format 0, and cyclic shift sequence indices 0 to 11 and orthogonal code sequence indices 0 to 6 can be configured for PUCCH format 1.

[0077] Furthermore, as mentioned above, only 4 bits in the RMSI can be used to indicate the set of PUCCH resources used to send ACK / NACK for message 4 during the initial access period (before the RRC connection is established). Therefore, resource allocation cannot be as flexible as the allocation of PUCCH resources for ACK / NACK data transmission after the RRC connection is established.

[0078] In this regard, one aspect of this disclosure will give a description of a method for allocating PUCCH resources as flexibly as possible, even when only 4 bits in the RMSI are available to indicate the PUCCH resources prior to the completion of the RRC connection establishment in the NR (e.g., PUCCH resources for sending ACK / NACK for message 4).

[0079] Each embodiment will be described in detail below.

[0080] (Example 1)

[0081] [Overview of Communication Systems]

[0082] The communication system according to each embodiment of the present disclosure includes a base station 100 and a terminal 200.

[0083] Figure 1 This is a block diagram illustrating a portion of the configuration of a base station 100 according to each embodiment of the present disclosure. Figure 1 In the base station 100 shown, control unit 101 determines one of a plurality of sets (PUCCH resource sets), each set including one or more candidates for resources (PUCCH resources) used for the UL control channel during initial access, and determines one candidate from the one or more candidates included in the determined set. Transmitting unit 114 indicates the determined set to terminal 200 via higher-layer signaling (e.g., 4 bits in RMSI) and indicates the determined candidate to terminal 200 via dynamic signaling (e.g., PUCCH resource indicator in DCI). Receiving unit 116 uses the resources corresponding to the determined candidate in the determined set to receive UL control signals (e.g., ACK / NACK for message 4).

[0084] Figure 2 This is a block diagram illustrating a portion of the configuration of a terminal 200 according to each embodiment of the present disclosure. Figure 2In the terminal 200 shown, receiving unit 202 receives higher-layer signaling indicating any set of multiple sets, where each set includes one or more candidates for resources used for the UL control channel during initial access, and receives dynamic signaling indicating any candidate included in the one or more candidates of the indicated set. Sending unit 215 uses resources corresponding to the candidate indicated by the dynamic signaling among the one or more candidates included in the set indicated by the higher-layer signaling to send UL control signals (e.g., ACK / NACK for message 4).

[0085] In one aspect of this disclosure, each parameter related to initial access is configured with an association between a value indicated by higher-layer signaling (e.g., 4 bits in RMSI) and multiple sets (PUCCH resource sets).

[0086] [Base station configuration]

[0087] Figure 3 This is a block diagram illustrating the configuration of a base station 100 according to Embodiment 1 of the present invention. Figure 3 In this system, base station 100 includes control unit 101, data generation unit 102, encoding unit 103, retransmission control unit 104, modulation unit 105, higher layer control signal generation unit 106, encoding unit 107, modulation unit 108, DL control signal generation unit 109, encoding unit 110, modulation unit 111, signal dispatch unit 112, inverse fast Fourier transform (IFFT) processor 113, transmission unit 114, antenna 115, reception unit 116, fast Fourier transform (FFT) processor 117, extraction unit 118, demodulation unit and / or decoding unit (hereinafter referred to as demodulation unit / decoding unit) 119, and determination unit 120.

[0088] Control unit 101 determines the set of PUCCH resources for the period prior to the completion of RRC connection establishment, which will be indicated to terminal 200 (e.g., PUCCH resources for sending ACK / NACK for message 4). Control unit 101 outputs the determined information to higher-layer control signal generation unit 106.

[0089] Furthermore, the control unit 101 determines the UL resources for the ACK / NACK of message 4 for terminal 200 in the PUCCH resource set for sending ACK / NACK for message 4 (i.e., information related to the actual resource usage indicated by the PUCCH resource indicator of DCI). The control unit 101 outputs the determined information to the DL control information generation unit 109.

[0090] The control unit 101 outputs the determined information to the extraction unit 118 so as to correctly receive signals from the terminal 200.

[0091] In addition, the control unit 101 determines the radio resource allocation for DL ​​data (e.g., message 4) for terminal 200, and outputs DL resource allocation information for indicating the resource allocation for DL ​​data to the DL control signal generation unit 109 and the signal dispatch unit 112.

[0092] The data generation unit 102 generates DL data (e.g., message 4) for the terminal 200 and outputs the DL data to the encoding unit 103.

[0093] The encoding unit 103 applies error correction encoding to the DL data input from the data generation unit 102 and outputs the encoded data signal to the retransmission control unit 104.

[0094] During the initial transmission, the retransmission control unit 104 holds the encoded data signal input from the encoding unit 103 and also outputs the encoded data signal to the modulation unit 105. Furthermore, when a NACK for the transmitted data signal is input from the determination unit 122 (described below), the retransmission control unit 104 outputs the corresponding data held therein to the modulation unit 105. Simultaneously, when an ACK for the transmitted data signal is input from the determination unit 122, the retransmission control unit 104 deletes the corresponding data held therein.

[0095] The modulation unit 105 modulates the data signal input from the retransmission control unit 104 and outputs the modulated data signal to the signal dispatch unit 112.

[0096] The higher-level control signal generation unit 106 uses the control information input from the control unit 101 (e.g., the PUCCH resource set for ACK / NACK of message 4) to generate a control information bit sequence (e.g., RMSI), and outputs the generated control information bit sequence to the encoding unit 107.

[0097] The encoding unit 107 applies error correction coding to the control information bit sequence input from the high-level control signal generation unit 106, and outputs the encoded control signal to the modulation unit 108.

[0098] The modulation unit 108 modulates the control signal input from the encoding unit 107 and outputs the modulated control signal to the signal dispatch unit 112.

[0099] The DL control signal generation unit 109 uses the control information input from the control unit 101 (information about the UL resources to be actually used by the terminal 200 and DL resource allocation information) to generate a control information bit sequence (e.g., DCI) and outputs the generated control information bit sequence to the encoding unit 110. Note that the DL control signal generation unit 109 may include the terminal ID of each terminal in the control information for each terminal, because the control information can be sent to multiple terminals.

[0100] The encoding unit 110 applies error correction coding to the control information bit sequence input from the DL control signal generation unit 109 and outputs the encoded control signal to the modulation unit 112.

[0101] The modulation unit 111 modulates the control signal input from the encoding unit 110 and outputs the modulated control signal to the signal dispatching unit 112.

[0102] Based on the DL resource allocation information input from the control unit 101, the signal dispatch unit 112 maps the data signal input from the modulation unit 105 to radio resources. Furthermore, the signal dispatch unit 112 maps the control signal input from the modulation unit 108 or modulation unit 111 to radio resources. The signal dispatch unit 112 then outputs the mapped DL signal to the IFFT processor 113.

[0103] The IFFT processor 113 applies transmission waveform generation processing, such as Orthogonal Frequency Division Multiplexing (OFDM), to the signal input from the signal dispatch unit 112. In the case of OFDM transmissions where a cyclic prefix (CP) (not shown) has already been added, the IFFT processor 113 adds a cyclic prefix (CP). The IFFT processor 113 outputs the generated transmission waveform to the transmission unit 114.

[0104] The transmitting unit 114 applies radio frequency (RF) processing, such as digital-to-analog (D / A) conversion and / or up-conversion, to the signal input from the IFFT processor 113, and transmits the radio signal to the terminal 200 via the antenna 115.

[0105] The receiving unit 116 applies RF processing, such as down-conversion or analog-to-digital (A / D) conversion, to the UL signal waveform received from the terminal 200 via the antenna 115, and outputs the resulting received signal to the FFT processor 117.

[0106] The FFT processor 117 applies an FFT process to the UL signal waveform input from the receiving unit 116 to convert the time-domain signal into a frequency-domain signal. The FFT processor 117 outputs the frequency-domain signal obtained through the FFT process to the extraction unit 118.

[0107] Based on the information received from the control unit 101 (information about the UL resources to be actually allocated to the terminal 200), the extraction unit 118 extracts the radio resources that have sent ACK / NACK from the signal input from the FFT processor 117, and outputs the components (ACK / NACK) of the extracted radio resources to the demodulation unit / decoding unit 119.

[0108] The demodulation / decoding unit 119 applies equalization, demodulation, and error correction decoding to the signal input from the extraction unit 118, and outputs the decoded bit sequence to the determination unit 120.

[0109] Based on the bit sequence input from the demodulation / decoding unit 119, the determining unit 120 determines whether the data signal transmitted by the ACK / NACK indication sent from the terminal 200 is ACK or NACK. The determining unit 120 outputs the determination result to the retransmission control unit 104.

[0110] [Terminal Configuration]

[0111] Figure 4 This is a block diagram illustrating the configuration of terminal 200 according to Embodiment 1 of the present disclosure. Figure 4 In the terminal 200, there are antenna 201, receiving unit 202, FFT processor 203, extraction unit 204, DL control signal demodulation unit 205, higher layer control signal demodulation unit 206, DL data signal demodulation unit 207, error detection unit 208, control unit 209, ACK / NACK generation unit 210, encoding unit 211, modulation unit 212, signal dispatching unit 213, IFFT processor 214, and transmitting unit 215.

[0112] The receiving unit 202 applies RF processing, such as down-conversion or analog-to-digital (A / D) conversion, to the signal waveform of the DL signal (data signal or control signal) received from the base station 100 via the antenna 201, and outputs the resulting received signal (baseband signal) to the FFT processor 203.

[0113] The FFT processor 203 applies FFT processing to the signal (time-domain signal) input from the receiving unit 202 to convert the time-domain signal into a frequency-domain signal. The FFT processor 203 outputs the frequency-domain signal obtained through the FFT processing to the extraction unit 204.

[0114] Extraction unit 204 extracts the DL control signal (DCI) from the signal input from FFT processor 203 based on the control information input from control unit 209, and outputs the DL control signal to DL control signal demodulation unit 205. Furthermore, extraction unit 204 extracts higher-level control signals (e.g., RMSI) and DL data signals (e.g., message 4) based on the control information input from control unit 209, and outputs the higher-level control signals to higher-level control signal demodulation unit 206 and the DL data signals to DL data signal demodulation unit 207.

[0115] The DL control signal demodulation unit 205 performs blind decoding on the DL control signal input from the extraction unit 204. When it is determined that the DL control signal is a control signal sent to the terminal 200 of the DL control signal demodulation unit 205, the DL control signal demodulation unit 205 demodulates the control signal and outputs the control signal to the control unit 209.

[0116] The high-rise control signal demodulation unit 206 demodulates the high-rise control signal input from the extraction unit 204 and outputs the demodulated high-rise control signal to the control unit 209.

[0117] The DL data signal demodulation unit 207 demodulates and / or decodes the DL data signal input from the extraction unit 204, and outputs the decoded signal to the error detection unit 208.

[0118] Error detection unit 208 performs error detection on the DL data input from DL data signal demodulation unit 207 and outputs the error detection result to ACK / NACK generation unit 210. Furthermore, error detection unit 208 outputs DL data that is determined to be error-free based on the error detection result as received data.

[0119] Furthermore, the control unit 209 calculates the radio resource allocation for the DL data signal based on the DL resource allocation information indicated by the control signal input from the DL control signal demodulation unit 205, and outputs the information indicating the radio resource allocation obtained by the calculation to the extraction unit 204.

[0120] Furthermore, the control unit 209 uses the higher-level control signals (the set of ACK / NACK PUCCH resources for message 4 indicated by RMSI) input from the higher-level control signal demodulation unit 206 and the control signals (information related to the UL resources to be actually used by the terminal 200 as indicated by DCI) input from the DL control signal demodulation unit 205 to calculate the UL resources to be used by the terminal 200 (PUCCH resources for sending ACK / NACK for message 4) using the method described below. The control unit 209 then outputs the information related to the UL resources obtained through calculation to the signal dispatch unit 213.

[0121] The ACK / NACK generation unit 210 generates an ACK / NACK (ACK or NACK) for the received DL data (message 4) based on the error detection result input from the error detection unit 208. The ACK / NACK generation unit 210 outputs the generated ACK / NACK (bit sequence) to the encoding unit 211.

[0122] The encoding unit 211 applies error correction coding to the bit sequence input from the ACK / NACK generation unit 210 and outputs the encoded bit sequence (ACK / NACK) to the modulation unit 212.

[0123] The modulation unit 212 modulates the ACK / NACK input from the encoding unit 211 and outputs the modulated ACK / NACK to the signal dispatch unit 213.

[0124] Signal dispatch unit 213 maps the ACK / NACK input from modulation unit 212 to the radio resource indicated by control unit 209. Signal dispatch unit 213 outputs the mapped UL signal to IFFT processor 214.

[0125] The IFFT processor 214 applies transmission waveform generation processing, such as OFDM, to the signal input from the signal dispatch unit 213. In the case of OFDM transmissions where a cyclic prefix (CP) (not shown) is added, the IFFT processor 214 adds a cyclic prefix (CP). Alternatively, when the IFFT processor 214 needs to generate a single carrier waveform, a Discrete Fourier Transform (DFT) processor (not shown) can be added before the signal dispatch unit 213. The IFFT processor 214 outputs the generated transmission waveform to the transmission unit 215.

[0126] The transmitting unit 215 applies radio frequency (RF) processing, such as digital-to-analog (D / A) conversion and / or up-conversion, to the signal input from the IFFT processor 214, and transmits the radio signal to the base station 100 via the antenna 201.

[0127] [Operation of Base Station 100 and Terminal 200]

[0128] The operation of the base station 100 and terminal 200 with the above configuration will be described in detail below.

[0129] Figure 5 The processing flow of base station 100 and terminal 200 according to embodiment 1 is shown.

[0130] Base station 100 indicates a synchronization signal (primary synchronization signal (PSS)) / (secondary synchronization signal (SSS)) or system information (primary information block (MIB)) / (system information block (SIB)) to terminal 200 (ST101). Terminal 200 acquires the synchronization signal or system information (ST102).

[0131] Next, base station 100 determines a PUCCH resource set for the terminal 200 during the initial access period from multiple resource sets (ST103), and sends an RMSI (4 bits) indicating the determined PUCCH resource set to the terminal 200 (ST104). The terminal 200 receives the RMSI (higher-layer signaling) sent from base station 100 and obtains the PUCCH resource set during the initial access period (ST105).

[0132] Terminal 200 and base station 100 perform initial access (random access) procedures (or RRC connection establishment), etc. (ST106 to ST112).

[0133] More specifically, terminal 200 sends message 1 (PRACH preamble) to base station 100 (ST106). Base station 100 sends message 2, as a response to message 1 received in ST106, to terminal 200 (ST107).

[0134] Next, terminal 200 sends message 3 (ST108) to base station 100 to request an RRC connection. Upon receiving message 3 in ST108, base station 100 determines, from the PUCCH resource set determined in ST103, information related to the actual resource usage to be indicated to terminal 200 using DCI (ST109). More specifically, base station 100 determines a candidate from the candidates of PUCCH resources included in the PUCCH resource set determined in ST103.

[0135] Base station 100 indicates to terminal 200 information related to the determined PUCCH resources and DL control information (DCI) including DL resource allocation information related to message 4 (DL data), and sends message 4 including information related to RRC connection to terminal 200 (ST110). Terminal 200 receives the DCI and obtains information about the resource usage of message 4 and information about the resource usage of ACK / NACK of message 4 (ST111).

[0136] Then, terminal 200 uses the PUCCH resources identified based on the PUCCH resource set obtained in ST105 and the DCI (PUCCH resource indicator) obtained in ST111 to send ACK / NACK for message 4 to base station 100 (ST112).

[0137] The processing of base station 100 and terminal 200 up to the initial access phase has now been described.

[0138] like Figure 5 As described, base station 100 uses 4 bits in RMSI to indicate to terminal 200 a semi-static PUCCH resource set (PUCCH resource set) (i.e., PUCCH resources before the RRC connection is established) (ST104) related to the PUCCH resources to be used for sending ACK / NACK for message 4.

[0139] The parameters that form a PUCCH resource set include the symbol position within a time slot, the number of symbols within a time slot, the frequency position, the on / off state of the frequency hopping application (enabled / disabled), and the code resources (such as cyclic shift sequences or orthogonal codes). Additionally, a PUCCH resource set includes multiple PUCCH resources (resource candidates), each defined by a combination of multiple parameters. For example, a PUCCH resource set can include 4 or 8 PUCCH resources. However, the number of PUCCH resources included in a PUCCH resource set is not limited to 4 or 8.

[0140] Base station 100 indicates which PUCCH resource among the multiple PUCCH resources included in the PUCCH resource set will be actually used (ST110) by including a PUCCH resource indicator in the DL control signal (DCI) used for scheduling message 4. For example, if the number of PUCCH resources included in the PUCCH resource set is 4, then 2 bits of the DCI can be used for the PUCCH resource indicator. Furthermore, if the number of PUCCH resources included in the PUCCH resource set is 8, then 3 bits of the DCI can be used for the PUCCH resource indicator.

[0141] The number of DCI bits used for the PUCCH resource indicator is X bits, and the number of PUCCH resources included in the PUCCH resource set is greater than 2. X In addition to explicit indication of PUCCH resources by the PUCCH resource indicator, base station 100 can implicitly indicate PUCCH resources. As a function of implicitly indicating PUCCH resources, one method is available in which base station 100 indicates a subset of PUCCH resources via the DCI PUCCH resource indicator and implicitly indicates the PUCCH resources within the subset. For example, for implicit indication, the identifier of terminal 200 (C-RNTI: Cell Radio Network Temporary Identifier or IMSI: International Mobile Subscriber Identifier) ​​or the Control Channel Element (CCE) of the DL Control Channel (PDCCH: Physical Downlink Control Channel) used for DCI transmission to terminal 200 can be used. For example, PUCCH can be implicitly indicated based on C-RNTI, IMSI, or CCE using C-RNTI mod Z, IMSI mod Z, or CCE mod Z, etc. Here, the term "Z" refers to the number of PUCCH resources included in the subset of PUCCH resources.

[0142] For the PUCCH resources to be used to send ACK / NACK for message 4 (i.e., PUCCH resources before the RRC connection is established), the use of one of the following PUCCH formats has been discussed: PUCCH format 0 (short PUCCH and PUCCH capable of sending 1 or 2 bits of ACK / NACK) and PUCCH format 1 (long PUCCH capable of sending 1 or 2 bits of ACK / NACK) (see, for example, NPL 4).

[0143] In Example 1, the association between the 4 bits of RMSI (16 modes) and the PUCCH resource set used to send ACK / NACK for message 4 is distinguished according to the PUCCH format (this association is different between the case of using PUCCH format 0 and the case of using PUCCH format 1).

[0144] Figure 6A The diagram illustrates an example of a situation where the association between the 4 bits (16 modes) in the RMSI and the PUCCH resource set used to send ACK / NACK for message 4 is common between PUCCH format 0 and PUCCH format 1. Figure 6B This shows the 2 bits (4 modes from 0 to 3) of the DCI (PUCCH resource indicator) and... Figure 6A The associations between PUCCH resources (PUCCH resources (n,x), where x = 0 to 3) included in the configured PUCCH resource set (set(n), where n = 0 to 15). Furthermore, Figure 6C Definitions are shown Figure 6B The parameters of the PUCCH resource (n,x) configured in the configuration include: symbol position A(n,x) within the time slot, number of symbols B(n,x) within the time slot, frequency position (before frequency hopping) C(n,x), frequency position (after frequency hopping) D(n,x), on / off state of frequency hopping application (enabled / disabled), code resources (cyclic shift sequence E(n,x), orthogonal code F(n,x))), and the PUCCH format of the PUCCH resource (n,x). Figure 6A In this case, the base station can configure a total of 16 PUCCH resource sets for PUCCH format 0 and PUCCH format 1.

[0145] at the same time, Figure 7A An example is shown of the association between 4 bits (16 patterns) in the RMSI according to Embodiment 1 and the PUCCH resource set used to send ACK / NACK for message 4.

[0146] like Figure 7A The diagram illustrates the association between the 4 bits (16 modes) in the RMSI configured for each of PUCCH formats 0 and 1, and the PUCCH resource set used to send ACK / NACK for message 4. More specifically, in Example 1, the diagram shows the association between the values ​​indicated by higher-layer signaling (4 bits in the RMSI) for each PUCCH format configuration and multiple PUCCH resource sets.

[0147] Figure 7B This shows the 2-bit (4 modes from 0 to 3) of DCI (PUCCH Resource Indicator) for PUCCH format 0, and includes... Figure 7A The associations between PUCCH resources (PUCCH resource (0,n,x), where x = 0 to 3) within the configured PUCCH resource set (set (0,n), where n = 0 to 15). Furthermore, Figure 7C This shows the definition for PUCCH format 0. Figure 7B The parameters of the PUCCH resource (0,n,x) configured in the configuration include: symbol position A(0,n,x) within the time slot, number of symbols B(0,n,x) within the time slot, frequency position (before frequency hopping) C(0,n,x), frequency position (after frequency hopping) D(0,n,x), on / off state of frequency hopping application, and code resource (circular shift sequence E(0,n,x)). Note that in Figure 7C In this context, the PUCCH format is PUCCH format 0.

[0148] same, Figure 7DThis shows the 2-bit (0 to 3, 4 modes) of DCI (PUCCH Resource Indicator) for PUCCH format 1, and includes... Figure 7A The associations between PUCCH resources (PUCCH resource (1,n,x), where x = 0 to 3) within the configured PUCCH resource set (set (1,n), where n = 0 to 15). Furthermore, Figure 7E This shows the definition for PUCCH format 1. Figure 7D The parameters of the PUCCH resource (1,n,x) configured in the configuration include: symbol position A(1,n,x) within the time slot, number of symbols B(1,n,x) within the time slot, frequency position (before frequency hopping) C(1,n,x), frequency position (after frequency hopping) D(1,n,x), on / off state of frequency hopping, and code resources (cyclic shift sequence E(1,n,x) and orthogonal code F(1,n,x)). Note that in Figure 7E In this context, the PUCCH format is PUCCH format 1.

[0149] like Figure 7A As shown, in Embodiment 1, base station 100 can configure 16 PUCCH resource sets for each of PUCCH format 0 and PUCCH format 1, and can configure 32 PUCCH resource sets throughout the system. More specifically, according to Embodiment 1 ( Figure 7A ), and the case where a common PUCCH resource set is configured for each PUCCH format ( Figure 6A Compared to this, it makes it possible to increase the number of configurable PUCCH resource sets.

[0150] Furthermore, in Embodiment 1, for each PUCCH format, the association of 4 bits in the RMSI with the PUCCH resource set is configured. Therefore, base station 100 can configure parameters for the PUCCH resource set indicated by the 4 bits in the RMSI for each PUCCH format. In PUCCH format 0, for example, the orthogonal code F is not used. Therefore, since base station 100 does not need to indicate the orthogonal code F, base station 100 can add combinations of other parameters in the association between the 4 bits in the RMSI and the PUCCH resource set, such as... Figure 7C In cases where the orthogonal code F is not needed.

[0151] As described above, according to Embodiment 1, even when only 4 bits in the RMSI are available to indicate the PUCCH resource set during initial access, each parameter related to the PUCCH resource used to send ACK / NACK can be flexibly configured.

[0152] (Variation 1 of Example 1)

[0153] In Example 1, the association between the 4 bits (16 modes) in the RMSI and the PUCCH resource set used to send ACK / NACK for message 4 is distinguished according to the PUCCH format (this association is different between the case of using PUCCH format 0 and the case of using PUCCH format 1).

[0154] In this case, terminal 200 needs to pre-identify which PUCCH format (PUCCH format 0 (short PUCCH) or PUCCH format 1 (long PUCCH)) will be used. The method for terminal 200 to identify the PUCCH format will be described below.

[0155] <Method 1-1>

[0156] Terminal 200 can be based on Figure 8 The sending mode of message 2 or message 3 in the RACH process shown determines which PUCCH format to use for sending ACK / NACK for message 4 (which one of PUCCH format 0 and PUCCH format 1 to use). Note that... Figure 8 It shows in Figure 5 The processing shown includes the sending of messages (ST106 to ST108 and ST110) and the sending of ACK / NACK for message 4 (ST112).

[0157] When message 2 or message 3 is transmitted based on time slots (transmitted in units of time slots) (PDSCH mapping type A), for example, terminal 200 may use PUCCH format 1 to transmit ACK / NACK for message 4. And when message 2 or message 3 is transmitted non-time slot-based (not transmitted in units of time slots) (PDSCH mapping type B or based on micro-time slots (in units of micro-time slots)), for example, terminal 200 may use PUCCH format 0 to transmit ACK / NACK for message 4.

[0158] Therefore, the overhead used to indicate the PUCCH format from base station 100 to terminal 200 can be reduced.

[0159] <Method 1-2>

[0160] Terminal 200 can determine, based on the information explicitly indicated by message 4, which PUCCH format (either PUCCH format 0 or PUCCH format 1) will be used to send the ACK / NACK for message 4.

[0161] Therefore, for example, base station 100 can dynamically change the PUCCH format at the time of message 4 transmission according to the operating conditions of terminal 200.

[0162] <Methods 1-3>

[0163] Terminal 200 can be based on, for example Figure 9 The sending mode of message 4 in the RACH process shown determines which PUCCH format to use for sending ACK / NACK for message 4 (whether to use PUCCH format 0 or PUCCH format 1). Note that... Figure 9 It shows in Figure 5 The processing shown includes the sending of messages (ST106 to ST108 and ST110) and the sending of ACK / NACK for message 4 (ST112).

[0164] When message 4 is transmitted based on time slots (transmitted in units of time slots) (PDSCH mapping type A), for example, terminal 200 can use PUCCH format 1 to transmit ACK / NACK for message 4. And when message 4 is transmitted non-time slots (not transmitted in units of time slots) (PDSCH mapping type B), for example, terminal 200 can use PUCCH format 0 to transmit ACK / NACK for message 4.

[0165] Therefore, the overhead for indicating the PUCCH format from base station 100 to terminal 200 can be reduced, and base station 100 can dynamically change the PUCCH format.

[0166] (Variation 2 of Example 1)

[0167] In Example 1, the association between the 4 bits (16 modes) in the RMSI and the PUCCH resource set used to send ACK / NACK for message 4 is distinguished according to the PUCCH format (this association is different between the case of using PUCCH format 0 and the case of using PUCCH format 1).

[0168] Base station 100 can be configured with 16 PUCCH resource sets for each of PUCCH format 0 and PUCCH format 1, such as Figure 7A As shown. However, as mentioned above, the parameters defining PUCCH resources include, for example, the symbol position within a time slot, the number of symbols within a time slot, the frequency position, the on / off state of the frequency hopping application (enabled / disabled), and the code resources (cyclic shift sequence or orthogonal code). Therefore, it is difficult to flexibly configure all parameters (combinations) using only 4 bits in RMSI.

[0169] In this regard, in Variation 2, the terminal 200 is indicated with a PUCCH resource set one or more parameters relating to the PUCCH resources used for sending ACK / NACK for message 4, and the remaining parameters are configured without being indicated by the PUCCH resource set. Examples of parameters that are neither indicated by the RMSI nor included in the PUCCH resource set could be values ​​determined by the specification or by the operating mode when the terminal 200 performs initial access. As described herein, not indicating one or more parameters defining the PUCCH resources and pre-determining these parameters allows for flexible configuration of the parameters to be indicated by the PUCCH resource set.

[0170] The following describes a method for determining parameters in Variant Example 2 that are not indicated by the PUCCH resource. Note that the <Methods 2-1 to 2-7> for determining parameters described below can be used individually or in combination.

[0171] <Method 2-1>

[0172] For example, in PUCCH format 0 (short PUCCH), one or two symbols can be configured as the number of symbols in a time slot. However, sending a PUCCH for ACK / NACK of message 4 requires robust transmission. In this regard, in method 2-1, the number of symbols used for PUCCH format 0 is fixed at two symbols, as shown below. Figure 10 As shown.

[0173] Setting a fixed value for the number of symbols eliminates the need for base station 100 to use 4 bits of the RMSI to indicate the number of symbols within a time slot for PUCCH format 0. More specifically, the number of symbols can be removed from the PUCCH resource set (set (0,n)) (e.g., Figure 7C The parameter B(0,n,x) in the RMSI allows base station 100 to use 4 bits in the RMSI to more flexibly configure another parameter to be included in the PUCCH resource set. Furthermore, terminal 200 can use two fixed symbols to robustly send ACK / NACK for message 4.

[0174] Note that in some cases, PUCCH format 0 is used to achieve low latency initial access. In these cases, the number of symbols for PUCCH format 0 can be fixed at one symbol (not shown). Therefore, low latency can be achieved in initial access.

[0175] <Method 2-2>

[0176] In PUCCH format 1 (long PUCCH), for example, 11 candidates of 4 to 14 symbols can be configured as the number of symbols in a time slot. Using RMSI to indicate all 11 candidates makes it difficult to flexibly configure the remaining parameters. Furthermore, sending a PUCCH for ACK / NACK of message 4 requires robust transmission.

[0177] In this regard, in method 2-2, for PUCCH format 1, the number of symbols is fixed at 14, such as... Figure 11 As shown.

[0178] Setting a fixed value for the number of symbols eliminates the need for base station 100 to use 4 bits of the RMSI to indicate the number of symbols within a time slot for PUCCH format 1. More specifically, the number of symbols can be removed from the PUCCH resource set (set (1,n)) (e.g., Figure 7E The parameter B(0,n,x) in the RMSI allows base station 100 to use 4 bits in the RMSI to more flexibly configure another parameter to be included in the PUCCH resource set. Furthermore, terminal 200 can robustly send ACK / NACK for message 4 using a fixed set of 14 symbols.

[0179] In addition, such as Figure 11 As shown, when the number of symbols is fixed at a maximum of 14, the symbol position (start position) within a time slot is also fixed at symbol index 0 (the first symbol in the time slot). Therefore, in Figure 11 In PUCCH format 1, base station 100 does not need to use the 4 bits in RMSI to indicate not only the number of symbols in the time slot (parameter B(1,n,x)), but also the symbol position (i.e., Figure 7E The parameter A(1,n,x) is shown in the figure. Therefore, base station 100 can use 4 bits in RMSI to configure another parameter more flexibly.

[0180] Note that when multiple coverages need to be supported during initial access, multiple candidates can be configured for the number of symbols. In addition to the 14 symbols mentioned above, candidates for the number of symbols can be configured, for example, 7 or 10 symbols.

[0181] Note that the number of symbols indicated by RMSI is not limited to 7, 10, or 14 symbols, and can be any other number of symbols. More specifically, in method 2-2, RMSI can be used to indicate only one or some of the 11 candidates that can be configured as a number of symbols.

[0182] Furthermore, terminal 200 can implicitly determine the number of symbols for the PUCCH resource based on the slot format indicated by MIB or RMSI. In this case, base station 100 no longer needs to use 4 bits in the RMSI to indicate the number of symbols within a slot (parameter B).

[0183] <Method 2-3>

[0184] For example, in PUCCH format 0 (short PUCCH), 14 candidate symbols with indices 0 to 13 can be configured as symbol positions in a time slot. Using RMSI to indicate all 14 candidates would limit the flexibility to configure the remaining parameters.

[0185] In this regard, in methods 2-3, such as Figure 12 As shown, for PUCCH format 0, the symbol position (start position) within a time slot is fixed to the second symbol from the end of the time slot (i.e., symbol index 12).

[0186] Setting a fixed value for the symbol position within a time slot eliminates the need for base station 100 to use 4 bits from the RMSI to indicate the symbol position within a time slot for PUCCH format 0. More specifically, the symbol position can be removed from the PUCCH resource set (set (0,n)) (e.g., Figure 7C The parameter A(0,n,x) in the RMSI. Therefore, base station 100 can use 4 bits in the RMSI to more flexibly configure another parameter to be included in the PUCCH resource set.

[0187] In addition, such as Figure 12 As shown, with the symbol position fixed at symbol index 12, the number of symbols within a time slot can be configured to a fixed value (2 symbols). Figure 12 In PUCCH format 0, base station 100 does not need to use the 4 bits in RMSI to indicate not only the symbol position within the time slot (parameter A(0,n,x)), but also the number of symbols (e.g., Figure 7C The parameter B(0,n,x) is shown in the diagram. Therefore, base station 100 can use 4 bits in the RMSI to configure another parameter more flexibly.

[0188] Note that the symbol position indicated by RMSI is not limited to symbol number 12, but can be another symbol position. More specifically, in methods 2-3, among the 14 candidates that can be configured as symbol positions, RMSI can be used to indicate only one or some of the candidates. The symbol position indicated by RMSI can be, for example, symbol index 13 (the last symbol in the time slot). Furthermore, if the symbol position is fixed at symbol index 13, the number of symbols in the time slot can be fixed to a fixed value (one symbol).

[0189] <Method 2-4>

[0190] In PUCCH format 1 (long PUCCH), for example, 11 candidates with symbol indices 0 to 10 can be configured as symbol positions in a time slot. Using RMSI to indicate all 11 candidates would limit the flexibility to configure the remaining parameters.

[0191] In this regard, in methods 2-4, the symbol position within a time slot is limited to one or more configurable values ​​(11 candidates) for PUCCH format 1 (not shown) (e.g., one or more symbol positions).

[0192] Therefore, when the symbol position within a time slot is fixed to one symbol position, for PUCCH format 1, base station 100 no longer needs to use 4 bits in the RMSI to indicate the symbol position within the time slot (parameter A(1,n,x)). Furthermore, when the symbol position within a time slot is fixed to certain symbol positions, the number of bits required to indicate the symbol position from base station 100 to terminal 200 can be reduced. Therefore, 4 bits in the RMSI can be used to configure another parameter more flexibly.

[0193] Note that, as described in <Method 2-2>, when only 14 symbols are used as the number of symbols, the symbol position is always configured as symbol number 0. Therefore, base station 100 no longer needs to indicate... Figure 11 The symbol position within the time slot (parameter A(1,n,x)). Furthermore, when the number of symbols can be configured to be 7, for example, the symbol position can be limited to symbol number 7. Similarly, in this case, base station 100 no longer needs to indicate the symbol position within the time slot.

[0194] <Method 2-5>

[0195] For example, in PUCCH format 0 (short PUCCH) and PUCCH format 1 (long PUCCH), the on-off state (enabled / disabled) of the frequency hopping application is typically configurable (however, in the case of one symbol of PUCCH format 0, there is no frequency hopping application). Furthermore, sending PUCCH ACK / NACK for message 4 requires robust transmission.

[0196] In this regard, in methods 2-5, such as Figure 13A and 13BAs shown, frequency hopping is always applied (enabled). More specifically, the parameter indicating the on-off state (enabled / disabled) of frequency hopping always indicates the on state (enabled). Therefore, for PUCCH format 0 (in the case of 2 symbols) and PUCCH format 1, base station 100 no longer needs to use 4 bits in the RMSI to indicate the on-off state (enabled / disabled) of frequency hopping. More specifically, the value indicating the on-off state (enabled / disabled) of frequency hopping can be removed from the PUCCH resource set. Figure 13A and Figure 13B (The value of "frequency hopping" is shown). Therefore, base station 100 can use 4 bits in RMSI to more flexibly configure another parameter to be included in the PUCCH resource set. In addition, terminal 200 can robustly send ACK / NACK for message 4 by applying frequency hopping.

[0197] Note that in methods 2-5, it is also possible to configure frequency hopping to not be applied at all (always disabled). More specifically, the parameter indicating the on-off state (enabled / disabled) of frequency hopping application can always indicate the off state (disabled). Also in this case, for PUCCH format 0 and PUCCH format 1, base station 100 no longer needs to use the 4 bits in the RMSI to indicate the on-off state (enabled / disabled) of frequency hopping application.

[0198] <Method 2-6>

[0199] When frequency hopping is applied, for example in PUCCH format 0 (short PUCCH, in the case of 2 symbols) and PUCCH format 1 (long PUCCH), PRB indices 0 to 274 can typically be configured as the frequency position after the frequency hopping is applied (the PRB index of the second hop). However, it is difficult to use RMSI to indicate all candidates for PRB indices.

[0200] In this regard, in methods 2-6, such as Figure 14A As shown in Figure 14, the frequency position after the frequency hopping (the PRB index of the first hop) is determined based on the frequency position before the frequency hopping (the PRB index of the first hop). The frequency position after the frequency hopping can, for example, be configured as a mirror image of the frequency position before the frequency hopping, with the center of the initial UL band (initial uplink BWP: bandwidth portion) as the axis, configured to send ACK / NACK PUCCH messages for message 4. Note that the frequency position after the frequency hopping can be determined by another association, and is not limited to a mirror image of the frequency position before the frequency hopping.

[0201] Therefore, for PUCCH format 0 (in the case of 2 symbols) and PUCCH format 1, base station 100 no longer needs to use 4 bits in the RMSI to indicate the frequency position after frequency hopping. More specifically, the frequency position (PRB index of the second hop) (parameter D) can be removed from the PUCCH resource set. Therefore, base station 100 can use 4 bits in the RMSI to more flexibly configure another parameter to be included in the PUCCH resource set.

[0202] <Method 2-7>

[0203] For example, in PUCCH format 0 (short PUCCH) and PUCCH format 1 (long PUCCH), PRB indices 0 to 274 can be configured as frequency positions (PRB indices of the first hop). However, it is difficult to use RMSI to indicate all PRB index candidates.

[0204] In this regard, in methods 2-7, the frequency position (PRB index of the first hop) is associated with the initial UL BWP, in which a PUCCH for sending ACK / NACK for message 4 is configured. The frequency position (PRB index of the first hop) can, for example, be the PRB (a predetermined number of PRBs) at the edge of the initial UL BWP.

[0205] Therefore, for PUCCH format 0 (in the case of 2 symbols) and PUCCH format 1, base station 100 no longer needs to use 4 bits in the RMSI to indicate the frequency position (PRB index of the first hop), or the number of bits required for indication can be reduced. More specifically, the frequency position (PRB index of the first hop) (parameter C) can be removed from the PUCCH resource set, or the number of candidate frequency positions can be reduced. Thus, base station 100 can use 4 bits in the RMSI to more flexibly configure another parameter to be included in the PUCCH resource set.

[0206] (Variation 3 of Example 1)

[0207] PUCCH format 0 and PUCCH format 1 are sequence transmissions using computer-generated (CG) sequences. Therefore, when different sequences are assigned to different cells, inter-cell interference occurs due to the cross-correlation properties between the sequences. To suppress inter-cell interference, methods exist for using different frequency resources for different cells. In this case, using the cell ID to change the PUCCH frequency resource location for each cell makes it possible to reduce the impact of inter-cell interference.

[0208] In this regard, in Variation 3, the frequency positions (PRB index of the first hop and / or the PRB index of the second hop) of PUCCH format 0 (short PUCCH) and PUCCH format 1 (long PUCCH) are calculated based on the cell ID. The frequency position can be, for example, obtained by adding the offset of the PRB from the edge of the initial UL BWP using the cell ID as a function. Note that the method of calculating the frequency position using the cell ID is not limited to this method, and another method can be used.

[0209] Therefore, base station 100 no longer needs to use 4 bits in the RMSI to indicate the frequency location, or can reduce the number of bits required for indication. More specifically, the frequency location (parameter C or D) can be removed from the PUCCH resource set, or the number of candidate frequency locations can be reduced. Thus, base station 100 can use 4 bits in the RMSI to more flexibly configure another parameter to be included in the PUCCH resource set.

[0210] In addition, it can reduce inter-cell interference in PUCCH.

[0211] (Example 2)

[0212] The base station and terminal according to Embodiment 2 have a common basic configuration to the base station 100 and terminal 200 according to Embodiment 1, therefore, in combination Figure 3 and Figure 4 A description will be provided at that time.

[0213] Base station 100 can be configured with multiple resources in the system for terminal 200 to send message 1 during the RACH process. In this regard, in embodiment 2, the association between 4 bits (16 modes) in RMSI and the PUCCH resource set used to send ACK / NACK for message 4 is distinguished according to the resource of message 1 (hereinafter, message 1 resource). This association is different for different resources.

[0214] As described in Example 1, base station 100 uses 4 bits of the RMSI to indicate to terminal 200 the set of PUCCH resources related to the PUCCH resources to be used for sending ACK / NACK for message 4 (i.e., PUCCH resources before the RRC connection is established). Figure 5 ST104 in the middle).

[0215] As in Example 1, the parameters forming the PUCCH resource set include the symbol position within the time slot, the number of symbols within the time slot, the frequency position, the on / off state of the frequency hopping application (enabled / disabled), and the code resources (such as cyclic shift sequences or orthogonal codes). Furthermore, the PUCCH resource set includes multiple PUCCH resources, each defined by a combination of multiple parameters. For example, the number of PUCCH resources included in a PUCCH resource set can be 4 or 8. The number of PUCCH resources included in a PUCCH resource set is not limited to 4 or 8.

[0216] Furthermore, base station 100 indicates which PUCCH resource among the multiple PUCCH resources included in the PUCCH resource set will actually be used by means of a PUCCH resource indicator included in the DL control signal (DCI) for scheduling message 4. Figure 5 (ST110 in the PUCCH resource set). When the number of PUCCH resources included in the PUCCH resource set is 4, for example, 2 bits of DCI can be used for the PUCCH resource indicator. Furthermore, when the number of PUCCH resources included in the PUCCH resource set is 8, 3 bits of DCI can be used for the PUCCH resource indicator.

[0217] The number of DCI bits used for the PUCCH resource indicator is X bits, and the number of PUCCH resources included in the PUCCH resource set is greater than 2. X In addition to the explicit indication of PUCCH resources by the PUCCH resource indicator, base station 100 can implicitly indicate PUCCH resources. As a function of implicitly indicating PUCCH resources, one method is available in which base station 100 indicates a subset of PUCCH resources via the DCI PUCCH resource indicator, and implicitly indicates the PUCCH resources within the subset. For example, for implicit indication, PUCCH resources can be implicitly indicated using C-RNTI mod Z, IMSI mod Z, or CCE mod Z, based on the identifier of terminal 200 (C-RNTI or IMSI) or the CCE of the DL control channel (PDCCH) used for DCI transmission to terminal 200. Here, the term "Z" refers to the number of PUCCH resources included in the subset of PUCCH resources.

[0218] Figure 15A An example is shown of the association between the 4 bits (16 patterns) in the RMSI according to Embodiment 2 and the PUCCH resource set used to send ACK / NACK for message 4. For example... Figure 15A As shown, in Example 2, the 4 bits (16 patterns) in the RMSI and the configuration of multiple resources for each of the multiple message 1 resources (multiple resources are configured) Figure 15A The two PUCCH resource sets (Message 1 Resource 0 and Message 1 Resource 1) used to send ACK / NACK for Message 4 are associated. More specifically, in Embodiment 2, the association between the value (4 bits in RMSI) to be indicated by higher-layer signaling for each Message 1 resource set is configured with multiple PUCCH resource sets.

[0219] Figure 15B This shows the 2 bits (0 to 3 of the 4 modes) of the DCI (PUCCH resource indicator) for message 1 resource 0 and in Figure 15A The associations between PUCCH resources (PUCCH resources (0,n,x), where x = 0 to 3) included in the configured PUCCH resource set (set (0,n), where n = 0 to 15). Furthermore, Figure 15C This shows the definition to be made for resource 0 in message 1. Figure 15B The parameters of the PUCCH resource (0,n,x) configured in the configuration include: symbol position A(0,n,x) in the time slot, number of symbols B(0,n,x) in the time slot, frequency position (before frequency hopping) C(0,n,x), frequency position (after frequency hopping) D(0,n,x), on / off state of frequency hopping application (enabled / disabled), code resources (cyclic shift sequence E(0,n,x) and orthogonal code F(0,n,x))), and the PUCCH format of the PUCCH resource (0,n,x).

[0220] same, Figure 15D This shows the 2 bits (0 to 3 of the 4 modes) of the DCI (PUCCH resource indicator) for message 1 resource 1 and in Figure 15A The associations between PUCCH resources (PUCCH resources (1,n,x), where x = 0 to 3) included in the configured PUCCH resource set (set (1,n), where n = 0 to 15). Furthermore, Figure 15E This shows that for message 1 resource 1, the definition to be made is... Figure 15D The parameters of the PUCCH resource (1,n,x) configured in the configuration include: symbol position A(1,n,x) in the time slot, number of symbols B(1,n,x) in the time slot, frequency position (before frequency hopping) C(1,n,x), frequency position (after frequency hopping) D(1,n,x), on / off state of frequency hopping application (enabled / disabled), code resources (circular shift sequence E(1,n,x) and orthogonal code F(1,n,x))), and the PUCCH format of the PUCCH resource (1,n,x).

[0221] For example, the association between the 4 bits (16 modes) in the RMSI and the PUCCH resource set used to send ACK / NACK for message 4 is common regardless of the message 1 resource (see, for example, see...). Figure 6A The base station can be configured with a total of 16 PUCCH resource sets in the system.

[0222] In this regard, according to Embodiment 2, for example, since base station 100 can configure 16 PUCCH resource sets for each message 1 resource, it is possible to configure (16×N) PUCCH resource sets for N message 1 resources in the entire system. More specifically, according to Embodiment 2 ( Figure 15A This increases the number of configurable PUCCH resource sets compared to configuring a common PUCCH resource set regardless of message 1 resources.

[0223] As described above, according to Embodiment 2, even when only 4 bits in the RMSI are available to indicate the PUCCH resource set during initial access, parameters related to the PUCCH resources used for sending ACK / NACK can be flexibly configured.

[0224] Meanwhile, message 1 resources are typically configured in a way that avoids inter-cell interference between adjacent cells. Therefore, associating the PUCCH resource set used for sending ACK / NACK for message 4 with the message 1 resources has the advantage of simultaneously avoiding inter-cell interference of the PUCCH resources used for sending ACK / NACK for message 4.

[0225] Furthermore, due to the association between the Message 1 resource and the PUCCH resource used to send ACK / NACK for Message 4, for example, refer to... Figure 16A and Figure 16B The frequency resource (PRB of message 1) shown in the diagram determines the frequency location (PRB number) of the PUCCH resource used to send the ACK / NACK for message 4.

[0226] (Variation of Example 2)

[0227] In Embodiment 2, base station 100 can configure 16 PUCCH resource sets for each message 1 resource. However, for example, as described above, the parameters defining PUCCH resources include the symbol position within the time slot, the number of symbols within the time slot, the frequency position, the on / off state of the frequency hopping application (enabled / disabled), and the code resource (cyclic shift sequence or orthogonal code). Therefore, it is difficult to flexibly configure all parameters (combinations) using only 4 bits in the RMSI.

[0228] In this regard, in a variant of embodiment 2, for multiple parameters defining the PUCCH resources used to send ACK / NACK for message 4, as in <methods 2-1 to 2-7> in variant 2 of embodiment 1, one or some of the multiple parameters are indicated to the terminal 200 through the PUCCH resource set, and the remaining parameters of the multiple parameters are configured without being indicated through the PUCCH resource set.

[0229] Furthermore, regarding the PUCCH format, as in <Methods 1-1 to 1-3> of Variation 1 of Example 1, the PUCCH format may not be included in the indication via RMSI. Additionally, regarding the PUCCH format, it can be determined in association with message 1 based on the following methods other than <Methods 1-1 to 1-3>.

[0230] <Method 4-1>

[0231] Terminal 200 can be based on, for example Figure 17 The Message 1 resource in the RACH process shown determines which PUCCH format (PUCCH format 0 or PUCCH format 1) will be used to send the ACK / NACK for message 4. Note that... Figure 17 It shows in Figure 5 The processing shown includes the sending of messages (ST106 to ST108 and ST110) and the sending of ACK / NACK for message 4 (ST112).

[0232] For example, base station 100 can configure different Message 1 resources between the case where Message 2, Message 3, or Message 4 is transmitted based on time slots and the case where Message 2, Message 3, or Message 4 is transmitted non-time slots, and can associate different PUCCH formats with each Message 1 resource. Figure 17 In the case of sending message 1 using the time-slot-based message 1 resource (resource 0), terminal 200 selects PUCCH format 1 (long PUCCH), and in the case of sending message 1 using the non-time-slot-based message 1 resource (resource 1), terminal 200 selects PUCCH format 0 (short PUCCH).

[0233] Using this configuration, terminal 200 can identify the PUCCH format without the indication of RMSI, thereby reducing the overhead of indicating the PUCCH format from base station 100 to terminal 200.

[0234] <Method 4-2>

[0235] Terminal 200 can determine which PUCCH format (PUCCH format 0 or PUCCH format 1) to use for sending ACK / NACK for message 4 based on the message 1 format (which may be referred to as "PRACH format" or "preamble format"). Note that Figure 18 It shows in Figure 5 The processing shown includes the transmission of messages (ST106 to ST108 and ST110) and the transmission of ACK / NACK for message 4 (ST112).

[0236] NR supports multiple PRACH formats with different sequence lengths to support multiple coverage levels. Figure 18 In the case of sending message 1 using the PRACH format (short format) with a short sequence length, terminal 200 selects PUCCH format 0 for sending ACK / NACK for message 4, and in the case of sending message 1 using the PRACH format (short format) with a long sequence length, terminal 200 selects PUCCH format 1 for sending ACK / NACK for message 4.

[0237] Using this configuration, terminal 200 can identify the PUCCH format without the indication of RMSI, thereby reducing the overhead of indicating the PUCCH format from base station 100 to terminal 200.

[0238] (Example 3)

[0239] The base station and terminal according to Embodiment 3 have the same basic configuration as the base station 100 and terminal 200 according to Embodiment 1, and therefore will be combined here. Figure 3 and Figure 4 A description will be provided at that time.

[0240] Base station 100 is able to allocate resources for terminal 200 to send message 3 during the RACH process. In this regard, in embodiment 3, the association between the 4 bits (16 modes) in the RMSI and the PUCCH resource set used to send ACK / NACK for message 4 is distinguished according to the resources of message 3 (this association is different for different resources).

[0241] As described in Example 1, base station 100 uses 4 bits of the RMSI to indicate to terminal 200 the set of PUCCH resources related to the PUCCH resources to be used for sending ACK / NACK for message 4 (i.e., PUCCH resources before the RRC connection is established). Figure 5 ST104 in the middle).

[0242] As in Example 1, the parameters forming the PUCCH resource set include the symbol position within the time slot, the number of symbols within the time slot, the frequency position, the on / off state of the frequency hopping application (enabled / disabled), and the code resources (such as cyclic shift sequences or orthogonal codes). Furthermore, the PUCCH resource set includes multiple PUCCH resources, each defined by a combination of multiple parameters. For example, the number of PUCCH resources included in a PUCCH resource set can be 4 or 8. However, the number of PUCCH resources included in a PUCCH resource set is not limited to 4 or 8.

[0243] Furthermore, base station 100 indicates which PUCCH resource among the multiple PUCCH resources included in the PUCCH resource set will actually be used by means of a PUCCH resource indicator included in the DL control signal (DCI) for scheduling message 4. Figure 5 (ST110 in the PUCCH resource set). When the number of PUCCH resources included in the PUCCH resource set is 4, for example, 2 bits of the DCI can be used for the PUCCH resource indicator. Furthermore, when the number of PUCCH resources included in the PUCCH resource set is 8, 3 bits of the DCI can be used for the PUCCH resource indicator.

[0244] Furthermore, the number of DCI bits used for the PUCCH resource indicator is X bits and the number of PUCCH resources included in the PUCCH resource set is greater than 2. X In addition to explicit indication of PUCCH resources via PUCCH resource indicators, base station 100 can implicitly indicate PUCCH resources. As a function of implicitly indicating PUCCH resources, one method is available in which base station 100 indicates a subset of PUCCH resources via a DCI PUCCH resource indicator, and implicitly indicates the PUCCH resources within the subset. For example, for implicit indication, PUCCH resources can be implicitly indicated using C-RNTI mod Z, IMSI mod Z, or CCE mod Z, based on the identifier of terminal 200 (C-RNTI or IMSI) or the CCE of the DL control channel (PDCCH) used for DCI transmission to terminal 200. Here, the term "Z" refers to the number of PUCCH resources included in the subset of PUCCH resources.

[0245] Figure 19A An example is shown showing the association between 4 bits (16 patterns) in the RMSI according to Embodiment 3 and the PUCCH resource set used to send ACK / NACK for message 4. For example... Figure 19A As shown, in embodiment 3, for message 3 resources allocated to each terminal 200 ( Figure 19AEach of Message 3 Resources 0 and Message 3 Resources 1 is associated with a 4-bit (16 modes) RMSI and a PUCCH resource set used to send an ACK / NACK for Message 4. More specifically, in Embodiment 3, the association between each Message 3 Resource configuration and multiple PUCCH resource sets is configured via a value indicated by higher-layer signaling (4 bits in the RMSI).

[0246] Figure 19B This shows the 2 bits (4 modes from 0 to 3) of the DCI (PUCCH resource indicator) for message 3, resource 0. Figure 19A The associations between PUCCH resources (PUCCH resources (0,n,x), where x = 0 to 3) included in the configured PUCCH resource set (set (0,n), where n = 0 to 15). Furthermore, Figure 19C This shows that for message 3 resource 0, the definition to be made is... Figure 19B The parameters of the PUCCH resource (0,n,x) configured in the configuration include: symbol position A(0,n,x) in the time slot, number of symbols B(0,n,x) in the time slot, frequency position (before frequency hopping) C(0,n,x), frequency position (after frequency hopping) D(0,n,x), on / off state of frequency hopping application (enabled / disabled), code resources (cyclic shift sequence E(0,n,x) and orthogonal code F(0,n,x))), and the PUCCH format of the PUCCH resource (0,n,x).

[0247] same, Figure 19D This shows the 2 bits (0 to 3 of the 4 modes) of the DCI (PUCCH resource indicator) for message 3, resource 1. Figure 19A The associations between PUCCH resources (PUCCH resources (1,n,x), where x = 0 to 3) included in the configured PUCCH resource set (set (1,n), where n = 0 to 15). Furthermore, Figure 19E This shows that for message 3 resource 1, the definition is to be... Figure 19D The parameters of the PUCCH resource (1,n,x) configured in the configuration include: symbol position A(1,n,x) in the time slot, number of symbols B(1,n,x) in the time slot, frequency position (before frequency hopping) C(1,n,x), frequency position (after frequency hopping) D(1,n,x), on / off state of frequency hopping application (enabled / disabled), code resources (circular shift sequence E(1,n,x) and orthogonal code F(1,n,x))), and the PUCCH format of the PUCCH resource (1,n,x).

[0248] For example, the association between the 4 bits (16 modes) in the RMSI and the PUCCH resource set used to send ACK / NACK for message 4 is common regardless of the message 3 resource (see, for example, see...). Figure 6A The base station can be configured with a total of 16 PUCCH resource sets in the system.

[0249] In this regard, according to Embodiment 3, for example, since base station 100 can configure 16 PUCCH resource sets for each message 3 resource, (16×N) PUCCH resource sets can be configured for N message 3 resources in the entire system. More specifically, according to Embodiment 3 ( Figure 19A This makes it possible to increase the number of configurable PUCCH resource sets, compared to configuring a common PUCCH resource set regardless of message 3 resources.

[0250] As described above, according to Embodiment 3, even when only 4 bits in the RMSI are available to indicate the PUCCH resource set during initial access, parameters related to the PUCCH resources used for sending ACK / NACK can be flexibly configured.

[0251] Meanwhile, compared to the resource configuration of message 1, the resource configuration of message 3 allows for more flexible resource allocation. To this end, the PUCCH resource set used for sending ACK / NACK for message 4 is associated with the resources of message 3, allowing for more flexible PUCCH resource allocation for sending ACK / NACK for message 4.

[0252] Furthermore, due to the association between the message 3 resource and the PUCCH resource used to send ACK / NACK for message 4, for example, it can be referenced as follows: Figure 20A and Figure 20B The frequency resource (PRB of message 3) shown in message 3 determines the frequency location (PRB number) of the PUCCH resource used to send the ACK / NACK for message 4.

[0253] For the PUCCH resources used to send ACK / NACK for message 4, as in Methods 2-1 to 2-7 of Variation 2 of Embodiment 1, one or more parameters can be indicated to terminal 200 via the PUCCH resource set, and the remaining parameters can be configured without RMSI indication. Furthermore, for the PUCCH format, as in Methods 1-1 to 1-3 of Variation 1 of Embodiment 1, and Methods 4-1 and 4-2 of Variation 2 of Embodiment 2, the PUCCH format may not be included in the indication via RMSI.

[0254] Each embodiment of this disclosure has now been described.

[0255] Note that, regarding the PUCCH used to send ACK / NACK for message 4, in addition to the parameters mentioned above, terminal 200 also needs to identify which parameter set (numberology) (subcarrier spacing) will be used. For the parameter set (subcarrier spacing) used to send ACK / NACK for message 4, for example, the same parameter set (subcarrier spacing) as the parameter set of message 1 or message 3 can be used, or the parameter set can be determined in association with the parameter set (subcarrier spacing) of message 1 or message 3.

[0256] In addition, terminal 200 can determine the set of parameters (subcarrier spacing) for sending ACK / NACK for message 4 based on information explicitly indicated in the RACH configuration or information explicitly indicated to terminal 200 by base station 100 through message 4.

[0257] Furthermore, in the above embodiments, the case of distinguishing the association between the 4 bits in the RMSI and the PUCCH resource set for each PUCCH format, each message 1 resource, or each message 3 resource has been described. The parameter used as the basis for distinguishing the association between the 4 bits in the RMSI and the PUCCH resource set is not limited to the PUCCH format, message 1 resource, or message 3 resource, and can be any parameter related to the initial access (RACH procedure). The parameter used as the basis for changing the association between the 4 bits in the RMSI and the PUCCH resource set can be, for example, a pre-configured parameter used in the initial access process, and can be a parameter related to the operating mode (operating conditions) when performing the initial access process.

[0258] Furthermore, all or any two of Examples 1 to 3 can be applied simultaneously. Therefore, even more PUCCH resource sets can be configured.

[0259] This disclosure can be implemented in software, hardware, or software cooperating with hardware. Each functional block used in the description of each of the above embodiments can be partially or wholly implemented by an LSI such as an integrated circuit, and each process described in each embodiment can be partially or wholly controlled by the same LSI or a combination of LSIs. An LSI can be formed as a chip on its own, or a chip can be formed to include some or all of the functional blocks. An LSI can include data inputs and outputs coupled thereto. Depending on the level of integration, an LSI herein may be referred to as an IC, a system LSI, a super LSI, or an ultra-LSI. However, the techniques for implementing integrated circuits are not limited to LSIs and can be implemented using dedicated circuits, general-purpose processors, or special-purpose processors. Additionally, a field-programmable gate array (FPGA) programmable after the LSI is manufactured, or a reconfigurable processing unit in which the connections and settings of circuit cells arranged within the LSI can be reconfigured, can be used. This disclosure can be implemented as digital or analog processing. If future integrated circuit technologies replace LSIs due to advancements in semiconductor technology or other derivative technologies, future integrated circuit technologies can be used to integrate the functional blocks. Biotechnology can also be applied.

[0260] A base station according to the present disclosure includes: circuitry for determining a set from a plurality of sets, each set including one or more candidates for resources used for an uplink (UL) control channel during initial access, and determining a candidate from the one or more candidates included in the determined set; a transmitting unit for indicating the determined set to a terminal via higher-layer signaling and indicating the determined candidate to the terminal via dynamic signaling; and a receiving unit for receiving UL control signals using resources corresponding to the determined candidate in the determined set, wherein the value indicated by the higher-layer signaling for each of the one or more parameters related to initial access is configured to be associated with the plurality of sets.

[0261] In the base station according to this disclosure, one or more parameters relating to initial access include the format of the UL control channel.

[0262] In the base station according to this disclosure, one or more parameters related to initial access include resources for sending message 1 during initial access.

[0263] In the base station according to this disclosure, one or more parameters related to initial access include resources for sending message 3 during initial access.

[0264] In the base station according to this disclosure, one or more parameters relating to resources for the UL control channel are included in a defined set and indicated to the terminal, and the remaining parameter of the one or more parameters is configured without being indicated to the terminal through the defined set.

[0265] In the base station according to this disclosure: one of the remaining parameters includes the format of the UL control channel, and the format of the UL control channel is determined based on the transmission mode of message 2 or message 3 during initial access.

[0266] In the base station according to this disclosure: the remaining parameters of one or more parameters include the format of the UL control channel, and the format of the UL control channel is indicated to the terminal via message 4 during initial access.

[0267] In the base station according to this disclosure: one of the remaining parameters includes the format of the UL control channel, and the format of the UL control channel is determined based on the transmission mode of message 4 during initial access.

[0268] In a base station according to this disclosure: the remaining parameter of one or more parameters includes at least one of symbol position and number of symbols in a time slot, and at least one of symbol position and number of symbols in a time slot is a fixed value.

[0269] In a base station according to this disclosure: the remaining one of one or more parameters includes at least one in-slot symbol position, and the at least one in-slot symbol position is limited to one or more configurable values.

[0270] In a base station according to this disclosure: the remaining parameter of one or more parameters includes a value indicating the on-off state (enabled / disabled) of frequency hopping application, and frequency hopping is always applied.

[0271] In a base station according to this disclosure: the remaining one of one or more parameters includes a first frequency position after frequency hopping is applied, and the first frequency position is determined based on a second frequency position before frequency hopping is applied.

[0272] In the base station according to this disclosure: one of the other parameters includes a frequency location, and the frequency location is calculated based on the cell ID of the cell in which the terminal is located.

[0273] In the base station according to this disclosure, the format of the UL control channel is determined based on the resources to be used for sending message 1 during initial access.

[0274] In the base station according to this disclosure, the format of the UL control channel is determined based on the format of message 1 in the initial access.

[0275] In the base station according to this disclosure, the subcarrier spacing of the UL control channel is determined based on the subcarrier spacing during the transmission of message 1 or message 3 in the initial access.

[0276] In the base station according to this disclosure, the subcarrier spacing of the UL control channel is explicitly indicated from the base station to the terminal.

[0277] A terminal according to this disclosure includes: a receiving unit that receives higher-layer signaling indicating any set among a plurality of sets, wherein each set includes one or more candidates for resources used for an uplink (UL) control channel during initial access, and receives dynamic signaling indicating any candidate among the one or more candidates in the set indicated by the higher-layer signaling; and a transmitting unit that transmits UL control signals using resources corresponding to the candidate indicated by the dynamic signaling among the one or more candidates included in the set indicated by the higher-layer signaling, wherein the value indicated by the higher-layer signaling is configured to be associated with the plurality of sets for each of one or more parameters related to initial access.

[0278] A communication method according to this disclosure includes: determining a set from a plurality of sets, wherein each set includes one or more candidates for resources used for an uplink (UL) control channel during initial access, and determining a candidate from the one or more candidates included in the determined set; indicating the determined set to a terminal via higher-layer signaling, and indicating the determined candidate to the terminal via dynamic signaling; and receiving UL control signals using resources corresponding to the determined candidate in the determined set, wherein the value indicated by the higher-layer signaling for each of one or more parameters related to initial access is configured to be associated with the plurality of sets.

[0279] A communication method according to this disclosure includes: receiving higher-layer signaling indicating any set among a plurality of sets, wherein each set includes one or more candidates for resources used for an uplink (UL) control channel during initial access; and receiving dynamic signaling indicating any candidate among the one or more candidates for resources, the one or more candidates being included in the set indicated by the higher-layer signaling; and transmitting UL control signals using resources corresponding to the candidate indicated by the dynamic signaling among the one or more candidates included in the set indicated by the higher-layer signaling, wherein an association between the value indicated by the higher-layer signaling and the plurality of sets is configured for each of one or more parameters relating to initial access.

[0280] Industrial applicability

[0281] One aspect of this disclosure is useful in mobile communication systems.

[0282] Reference number list

[0283] 100 base stations

[0284] 101, 209 control units

[0285] 102 Data Generation Unit

[0286] Encoding units 103, 107, 110, and 211

[0287] 104 retransmission control unit

[0288] 105, 108, 111, 212 modulation units

[0289] 106 High-rise Control Signal Generation Unit

[0290] 109DL Control Signal Generation Unit

[0291] Signal dispatching units 112 and 213

[0292] 113, 214 IFFT processors

[0293] Transmitting units 114 and 215

[0294] 115, 201 antennas

[0295] Receiver units 116 and 202

[0296] 117, 203 FFT processors

[0297] Extraction units 118 and 204

[0298] 119 Demodulation / Decoding Unit

[0299] 120 Determining Unit

[0300] 200 terminals

[0301] 205DL Control Signal Demodulation Unit

[0302] 206 High-rise control signal demodulation unit

[0303] 207DL Data Signal Demodulation Unit

[0304] 208 Error Detection Unit

[0305] 211ACK / NACK generation unit

Claims

1. A user equipment, comprising: The circuit determines the PUCCH resources in the Physical Uplink Control Channel (PUCCH) resource set provided by cell-specific information, which is used to configure cell-specific PUCCH parameters for initial access. as well as At least one antenna uses the PUCCH resource to send an acknowledgment (ACK) message during initial access. Specifically, before instructing the PUCCH resource configuration information in the Radio Resource Control (RRC) signaling, the circuit determines the PUCCH resource. Before indicating the PUCCH resource configuration information, the at least one antenna always uses frequency hopping to transmit the ACK information, and the frequency hopping pattern is a mirror pattern with the center of the frequency band used in the previous uplink transmission during the initial access as the axis. The cell-specific information has 4 bits, and the cell-specific information indicates one of the 16 PUCCH resource sets. The association between the bits of the cell-specific information and one of the 16 PUCCH resource sets is set for each resource used by message 3 during the initial access period, and varies depending on the resource used by message 3.

2. The user equipment according to claim 1, in, The circuit determines the PUCCH resource based on the value of the PUCCH resource indicator included in the downlink control information (DCI). The number of PUCCH resources in the PUCCH resource set is greater than 2 raised to the power of the number of bits of the PUCCH resource indicator.

3. The user equipment according to claim 1, in, The frequency domain location of the PUCCH resource is determined based on the frequency resources used by message 3 during the initial access period.

4. A communication method for a user equipment, the communication method comprising: Determine the PUCCH resources in the Physical Uplink Control Channel (PUCCH) resource set provided by cell-specific information, which is used to configure cell-specific PUCCH parameters for initial access; and During initial access, the PUCCH resource is used to send acknowledgment (ACK) messages. Specifically, before instructing the PUCCH resource configuration information in the Radio Resource Control (RRC) signaling, the PUCCH resource is determined. Before indicating the PUCCH resource configuration information, frequency hopping is always used to send the ACK information, and the frequency hopping pattern is a mirror pattern with the center of the frequency band used in the previous uplink transmission during the initial access as the axis. The cell-specific information has 4 bits, and the cell-specific information indicates one of the 16 PUCCH resource sets. The association between the bits of the cell-specific information and one of the 16 PUCCH resource sets is set for each resource used by message 3 during the initial access period, and varies depending on the resource used by message 3.

5. An integrated circuit for use in a user equipment, said integrated circuit including control circuitry. The control circuit controls the following processes: Determine the PUCCH resources in the Physical Uplink Control Channel (PUCCH) resource set provided by cell-specific information, which is used to configure cell-specific PUCCH parameters for initial access; and During initial access, the PUCCH resource is used to send acknowledgment (ACK) messages. in, Before instructing the PUCCH resource configuration information in the Radio Resource Control (RRC) signaling, the PUCCH resource is determined. Before indicating the PUCCH resource configuration information, frequency hopping is always used to send the ACK information, and the frequency hopping pattern is a mirror pattern with the center of the frequency band used in the previous uplink transmission during the initial access as the axis. The cell-specific information has 4 bits, and the cell-specific information indicates one of the 16 PUCCH resource sets. The association between the bits of the cell-specific information and one of the 16 PUCCH resource sets is set for each resource used by message 3 during the initial access period, and varies depending on the resource used by message 3.

6. A base station, comprising: At least one antenna transmits cell-specific information during initial access for configuring cell-specific PUCCH parameters of the Physical Uplink Control Channel (PUCCH) resource set. as well as The receiving unit receives ACK information sent using PUCCH resources from the PUCCH resource set. Specifically, before instructing the PUCCH resource configuration information in the Radio Resource Control (RRC) signaling, the PUCCH resource is determined. Before indicating the PUCCH resource configuration information, frequency hopping is always used to send the ACK information, and the frequency hopping pattern is a mirror pattern with the center of the frequency band used in the previous uplink transmission during the initial access as the axis. The cell-specific information has 4 bits, and the cell-specific information indicates one of the 16 PUCCH resource sets. The association between the bits of the cell-specific information and one of the 16 PUCCH resource sets is set for each resource used by message 3 during the initial access period, and varies depending on the resource used by message 3.

7. The base station according to claim 6, in, The PUCCH resource is determined based on the value of the PUCCH resource indicator included in the downlink control information (DCI). The number of PUCCH resources in the PUCCH resource set is greater than 2 raised to the power of the number of bits of the PUCCH resource indicator.

8. The base station according to claim 6, in, The frequency domain location of the PUCCH resource is determined based on the frequency resources used by message 3 during the initial access period.

9. A communication method for a base station, the communication method comprising: During initial access, cell-specific information is sent to configure cell-specific PUCCH parameters for the Physical Uplink Control Channel (PUCCH) resource set; as well as Receive ACK information sent using PUCCH resources from the PUCCH resource set. Specifically, before instructing the PUCCH resource configuration information in the Radio Resource Control (RRC) signaling, the PUCCH resource is determined. Before indicating the PUCCH resource configuration information, frequency hopping is always used to send the ACK information, and the frequency hopping pattern is a mirror pattern with the center of the frequency band used in the previous uplink transmission during the initial access as the axis. The cell-specific information has 4 bits, and the cell-specific information indicates one of the 16 PUCCH resource sets. The association between the bits of the cell-specific information and one of the 16 PUCCH resource sets is set for each resource used by message 3 during the initial access period, and varies depending on the resource used by message 3.

10. An integrated circuit for use in a base station, said integrated circuit including control circuitry. The control circuit controls the following processes: During initial access, cell-specific information is sent for configuring cell-specific PUCCH parameters of the Physical Uplink Control Channel (PUCCH) resource set; and Receive ACK information sent using PUCCH resources from the PUCCH resource set. in, Before instructing the PUCCH resource configuration information in the Radio Resource Control (RRC) signaling, the PUCCH resource is determined. Before indicating the PUCCH resource configuration information, frequency hopping is always used to send the ACK information, and the frequency hopping pattern is a mirror pattern with the center of the frequency band used in the previous uplink transmission during the initial access as the axis. The cell-specific information has 4 bits, and the cell-specific information indicates one of the 16 PUCCH resource sets. The association between the bits of the cell-specific information and one of the 16 PUCCH resource sets is set for each resource used by message 3 during the initial access period, and varies depending on the resource used by message 3.

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