Base station, communication method, and integrated circuit

Abstract

To appropriately control interference in an uplink control channel that includes 1-2 bits of uplink control information.SOLUTION: In a terminal 200, a control unit 209 determines a sequence to be used for an uplink control channel in response to uplink control information, and a transmission unit 214 transmits the uplink control information using the sequence. Here, the sequence is calculated using cell identification information that identifies a cell to which the terminal 200 belongs, and sub-cell specific information related to at least one sub-cell included in the cell.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a terminal and a communication method. [Background technology]

[0002] With the recent spread of services using mobile broadband, data traffic in mobile communications has been increasing exponentially, and there is an urgent need to expand data transmission capacity for the future. In addition, a dramatic development of the Internet of Things (IoT), in which all "things" are connected via the Internet, is expected in the future. In order to support the diversification of services through IoT, not only data transmission capacity but also various other requirements such as low latency and communication area (coverage) are required to be dramatically improved. In response to this background, technological development and standardization of the fifth generation mobile communication system (5G), which will significantly improve performance and functions compared to the fourth generation mobile communication system (4G), is being promoted.

[0003] In the standardization of 5G, the Third Generation Partnership Project (3GPP) is developing a new radio access technology (NR: New Radio) that is not necessarily backward compatible with LTE (Long Term Evolution)-Advanced (see, for example, Non-Patent Documents 1-3).

[0004] In NR, it is being considered that a terminal (UE: User Equipment) will use an uplink control channel (PUCCH: Physical Uplink Control Channel) to transmit uplink control information (UCI: Uplink Control Information) such as a response signal (ACK / NACK: Acknowledgement / Negative Acknowledgment or HARQ-ACK) indicating the result of an error detection in downlink data, downlink channel state information (CSI: Channel State Information), and an uplink radio resource allocation request (SR: Scheduling Request) to a base station (eNG or gNB).

[0005] In addition, in NR, consideration is being given to transmitting 1- to 2-bit UCI by including it in the PUCCH.

[0006] In addition, NR supports "Short PUCCH," which transmits PUCCH using one or two symbols within one slot, and "Long PUCCH," which transmits PUCCH using three or more symbols (for example, the minimum number of symbols may be four symbols). [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] 3GPP TS 36.211 V13.4.0, "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation (Release 13),"December 2016. [Non-Patent Document 2] 3GPP TS 36.212 V13.4.0, “Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding (Release 13),” December 2016. [Non-Patent Document 3] 3GPP TS 36.213 V13.4.0, "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures (Release 13),"December 2016. [Non-Patent Document 4] R1-1612228, "Proposal of subcell," Panasonic, RAN1#87, Nov. 2016. Summary of the Invention [Problem to be solved by the invention]

[0008] However, a method for controlling interference in a PUCCH including 1-2 bits of UCI has not been fully investigated.

[0009] One aspect of the present disclosure contributes to providing a terminal and a communication method capable of appropriately controlling interference in a PUCCH including 1- to 2-bit UCI. [Means for solving the problem]

[0010] A terminal according to one embodiment of the present disclosure includes a circuit for determining a sequence to be used for an uplink control channel in response to uplink control information, and a transmitter for transmitting the uplink control information using the sequence, where the sequence is determined using cell identification information that identifies a cell to which the terminal belongs, and sub-cell specific information for at least one sub-cell included in the cell.

[0011] A terminal according to one embodiment of the present disclosure includes a circuit for determining a sequence to be used for an uplink control channel in response to uplink control information, and a transmitter for transmitting the uplink control information using the sequence, and limits the maximum number of the sequences that can be allocated within one resource block of the uplink control channel.

[0012] A terminal according to one embodiment of the present disclosure includes a circuit for determining a sequence to be used for an uplink control channel in response to uplink control information, and a transmitter for transmitting the uplink control information using the sequence, wherein the uplink control information includes at least an ACK and a NACK, and a cyclic shift used for the sequence is separated into a first region including a cyclic shift assigned to the ACK and a second region including a cyclic shift assigned to the NACK.

[0013] A communication method according to one embodiment of the present disclosure determines a sequence to be used for an uplink control channel in accordance with uplink control information, and transmits the uplink control information using the sequence, where the sequence is determined using cell identification information that identifies a cell to which a terminal belongs, and sub-cell specific information for at least one sub-cell included in the cell.

[0014] A communication method according to one embodiment of the present disclosure determines a sequence to be used for an uplink control channel in response to uplink control information, transmits the uplink control information using the sequence, and limits a maximum number of the sequences that can be allocated within one resource block of the uplink control channel.

[0015] A communication method according to one embodiment of the present disclosure determines a sequence to be used for an uplink control channel in accordance with uplink control information, and transmits the uplink control information using the sequence, where the uplink control information includes at least an ACK and a NACK, and a cyclic shift used in the sequence is separated into a first region including a cyclic shift assigned to the ACK and a second region including a cyclic shift assigned to the NACK.

[0016] These comprehensive or specific aspects may be realized as a system, a method, an integrated circuit, a computer program, or a recording medium, or may be realized as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium. Effect of the Invention

[0017] According to one embodiment of the present disclosure, it is possible to appropriately control interference in a PUCCH including 1- to 2-bit UCI.

[0018] Further advantages and benefits of certain aspects of the present disclosure will become apparent from the specification and drawings, in which such advantages and / or benefits are provided by some of the embodiments and features described in the specification and drawings, respectively, but not necessarily all of which are provided to obtain one or more identical features. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 shows an example of the sequence selection method. [Diagram 2] FIG. 2 shows a partial configuration of the terminal according to the first embodiment. [Diagram 3] FIG. 3 shows a configuration of the base station according to the first embodiment. [Figure 4] FIG. 4 shows the configuration of a terminal according to the first embodiment. [Diagram 5] FIG. 5 shows processing of the terminal according to the first embodiment. [Figure 6] FIG. 6 shows an example of a method for determining a sequence ID using a subcell ID according to the first embodiment. [Figure 7] FIG. 7 shows an example of a method for determining a sequence ID using a beam ID according to the first embodiment. [Figure 8] FIG. 8 shows an example of a method for determining a sequence ID using a random access resource according to the first embodiment. [Figure 9]FIG. 9 shows an example of determining a cyclic shift pattern of 1-bit UCI according to the second embodiment. [Figure 10] FIG. 10 shows an example of determining a cyclic shift pattern of a 2-bit UCI according to the second embodiment. [Figure 11A] FIG. 11A illustrates an example of determining a cyclic shift pattern of 1-bit UCI according to the third embodiment. [Figure 11B] FIG. 11B illustrates an example of determining a cyclic shift pattern of a 2-bit UCI according to the third embodiment. [Figure 12A] FIG. 12A shows an example of UCI mapping according to the fourth embodiment. [Figure 12B] FIG. 12B illustrates an example of UCI mapping according to the fourth embodiment. [Figure 13] FIG. 13 shows an example of mapping of 1-bit UCI according to the fourth embodiment. [Figure 14] FIG. 14 shows an example of mapping of 2-bit UCI according to the fourth embodiment. [Figure 15] FIG. 15 shows an example of mapping of 1-bit UCI according to the fifth embodiment. [Figure 16] FIG. 16 shows an example of mapping of 2-bit UCI according to the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0021] As shown in Fig. 1, for Short PUCCH, a method (hereinafter referred to as a Sequence Selection method) is being considered for selecting a sequence used for Short PUCCH transmission based on 1-bit or 2-bit UCI and the presence or absence of SR. In Fig. 1, a combination of the presence or absence of ACK / NACK and SR is associated with a cyclic shift (amount of cyclic shift). For example, as shown in Fig. 1, a cyclic shift of a CAZAC (Constant Amplitude Zero Auto Correlation) code sequence or a CG (Computer Generated) sequence can be used for sequence selection.

[0022] When using a Short PUCCH consisting of a CAZAC code sequence or a CG sequence, even if the sequences (sometimes called PUCCH sequences) used for PUCCHs transmitted from different terminals are different from each other, the PUCCH transmissions of those terminals are not completely orthogonal, so interference occurs due to the cross-correlation characteristics between the sequences. For example, the interference that occurs when different sequences are assigned between cells is called "inter-cell interference."

[0023] In addition, when the sequence used for the PUCCH transmitted from different terminals is the same, but the cyclic shifts used for the PUCCH transmitted from those terminals are different, if the time and frequency in the PUCCH transmission between those terminals are synchronized, the PUCCH transmissions of those terminals are completely orthogonal. On the other hand, when there is an influence of a transmission timing difference between terminals or a frequency selective fading channel, interference occurs even when the sequence used for the PUCCH transmitted from each terminal is the same and the cyclic shifts are different.

[0024] For the Short PUCCH, it is better to take into consideration the influence of the above-mentioned interference.

[0025] Here, 30 CG sequences are defined in LTE. The PUCCH for each cell is distinguished by identification information for identifying the cell (hereinafter, referred to as "cell ID"). If the cell ID is different, the CG sequence used for the PUCCH is different.

[0026] In addition, in LTE, in order to randomize the effect of interference, allocation of a CG sequence for PUCCH or determination of a cyclic shift pattern for PUCCH is applied based on a hopping pattern. If the cell ID is different, the initial value of the random sequence that determines the hopping pattern is different. In addition, in LTE, by using a virtual cell ID for generating a PUCCH signal sequence and setting the same cell ID between different cells, interference control can be performed when cells are synchronized, such as CoMP (Coordinated Multiple Point transmission and reception) (for example, see Non-Patent Document 1).

[0027] In NR, it is assumed that a plurality of TRPs (Transmission and Reception Points) are included in the same cell. In this case, it is necessary to distinguish between PUCCHs transmitted from terminals communicating with different TRPs in the same cell by using different PUCCH resources (cyclic shifts, time or frequency resources).

[0028] However, in the above-described allocation of PUCCH sequences based on cell IDs, the PUCCH resources required for PUCCH transmission of terminals communicating with different TRPs increase, and the frequency utilization efficiency of the uplink within the cell decreases.

[0029] In addition, by using the above-mentioned virtual cell ID to assign different cell IDs to terminals communicating with different TRPs, PUCCH resources in a cell can be distributed to different CG sequences. However, the virtual cell ID is notified by using a terminal-specific higher layer signal after the initial access is completed. For this reason, in the PUCCH transmission in the initial access stage (for example, an ACK / NACK response to message4), it is necessary to assign a PUCCH sequence based on the cell ID, not the virtual cell ID.

[0030] In one aspect of the present disclosure, a method for reducing the effect of interference in a wireless communication system that transmits a Short PUCCH will be described.

[0031] Each embodiment will be described in detail below.

[0032] (Embodiment 1) [Communication system overview] The communication system according to each embodiment of the present disclosure includes a base station 100 and a terminal 200.

[0033] Fig. 2 is a block diagram showing a configuration of a part of terminal 200 according to each embodiment of the present disclosure. In terminal 200 shown in Fig. 2, control unit 209 determines a sequence (PUCCH sequence) to be used for an uplink control channel (PUCCH) in accordance with uplink control information (UCI), and transmission unit 214 transmits the uplink control information using the above sequence. Here, the above sequence is calculated using cell identification information (cell ID) that identifies a cell to which terminal 200 belongs, and sub-cell specific information related to at least one sub-cell included in the cell.

[0034] [Base station configuration] Fig. 3 is a block diagram showing a configuration of a base station 100 according to the first embodiment of the present disclosure. In Fig. 3, the base station 100 includes a control unit 101, a data generating unit 102, an encoding unit 103, a retransmission control unit 104, a modulation unit 105, a higher-level control signal generating unit 106, an encoding unit 107, a modulation unit 108, a downlink control signal generating unit 109, an encoding unit 110, a modulation unit 111, a signal allocation unit 112, an IFFT (Inverse Fast Fourier Transform) unit 113, a transmission unit 114, an antenna 115, a reception unit 116, an FFT (Fast Fourier Transform) unit 117, an extraction unit 118, an SR detection unit 119, a PUCCH demodulation and decoding unit 120, and a determination unit 121.

[0035] The control unit 101 determines radio resource allocation for a downlink signal (for example, a Physical Downlink Shared Channel (PDSCH)), and outputs downlink resource allocation information instructing resource allocation for the downlink signal to the downlink control signal generation unit 109 and the signal allocation unit 112.

[0036] In addition, the control unit 101 determines PUCCH resource (time, frequency, sequence, etc.) allocation depending on the presence or absence of a HARQ-ACK signal and an SR for the downlink signal, and outputs information regarding the PUCCH resource allocation (PUCCH resource allocation information) to the higher control signal generation unit 106 (or the downlink control signal generation unit 109) and the extraction unit 118.

[0037] At this time, control section 101 determines the PUCCH sequence number or cyclic shift pattern as the PUCCH resource. Note that the method of determining the PUCCH resource will be described in detail later.

[0038] The data generator 102 generates downlink data for the terminal 200 and outputs the data to the encoder 103 .

[0039] The encoding unit 103 performs error correction coding on the downlink data input from the data generation unit 102 , and outputs the coded data signal to the retransmission control unit 104 .

[0040] At the time of the first transmission, retransmission control section 104 holds the coded data signal input from coding section 103 and outputs it to modulation section 105. Furthermore, when a NACK for the transmitted data signal is input from determination section 121 described later, retransmission control section 104 outputs the corresponding held data to modulation section 105. On the other hand, when an ACK for the transmitted data signal is input from determination section 121, retransmission control section 104 deletes the corresponding held data.

[0041] The modulation section 105 modulates the data signal inputted from the retransmission control section 104 and outputs the modulated data signal to the signal allocation section 112 .

[0042] Higher control signal generating section 106 generates a control information bit sequence using control information (eg, PUCCH resource allocation information) inputted from control section 101, and outputs the generated control information bit sequence to encoding section 107.

[0043] Encoding section 107 performs error correction coding on the control information bit string inputted from higher-level control signal generating section 106 and outputs the coded control signal to modulating section 108 .

[0044] Modulation section 108 modulates the control signal inputted from encoding section 107 and outputs the modulated control signal to signal allocation section 112 .

[0045] The downlink control signal generating unit 109 generates a downlink control information bit string (for example, DCI: Downlink Control Information) using control information (for example, downlink resource allocation information, PUCCH resource allocation information, etc.) input from the control unit 101, and outputs the generated control information bit string to the encoding unit 110. Note that since control information may be transmitted to multiple terminals, the downlink control signal generating unit 109 may generate a bit string by including the terminal ID of each terminal in the control information for each terminal.

[0046] The encoding section 110 performs error correction coding on the control information bit string inputted from the downlink control signal generating section 109 and outputs the coded control signal to the modulating section 111 .

[0047] The modulation unit 111 modulates the control signal input from the encoding unit 110 and outputs the modulated control signal to the signal allocation unit 112 .

[0048] The signal allocation unit 112 maps the data signal input from the modulation unit 105 to the radio resources indicated in the downlink resource allocation information input from the control unit 101. The signal allocation unit 112 also maps the control signal input from the modulation unit 108 or the modulation unit 111 to the radio resources. The signal allocation unit 112 outputs the downlink signal onto which the signal has been mapped to the IFFT unit 113.

[0049] The IFFT unit 113 performs transmission waveform generation processing such as OFDM on the signal input from the signal allocation unit 112. In the case of OFDM transmission in which a CP (Cyclic Prefix) is added, the IFFT unit 113 adds a CP (not shown). The IFFT unit 113 outputs the generated transmission waveform to the transmission unit 114.

[0050] The transmitting section 114 performs RF (Radio Frequency) processing such as D / A (Digital-to-Analog) conversion and up-conversion on the signal input from the IFFT section 113 , and transmits the wireless signal to the terminal 200 via the antenna 115 .

[0051] The receiving unit 116 performs RF processing such as down-conversion or A / D (Analog-to-Digital) conversion on the uplink signal waveform from the terminal 200 received via the antenna 115, and outputs the uplink signal waveform after the reception processing to the FFT unit 117.

[0052] The FFT unit 117 performs FFT processing on the uplink signal waveform input from the receiving unit 116 to convert a time domain signal into a frequency domain signal. The FFT unit 117 outputs the frequency domain signal obtained by the FFT processing to the extracting unit 118.

[0053] Based on information received from the control unit 101 (PUCCH resource allocation information, etc.), the extraction unit 118 extracts the PUCCH radio resource portion for SR or HARQ-ACK from the signal input from the FFT unit 117, and outputs the extracted radio resource components to the SR detection unit 119 and the PUCCH demodulation and decoding unit 120, respectively.

[0054] The SR detection unit 119 detects the presence or absence of an SR by performing power detection on the signal input from the extraction unit 118. Furthermore, when the SR detection unit 119 detects that an SR is present and that an HARQ-ACK is transmitted using an SR resource, the SR detection unit 119 outputs the signal input from the extraction unit 118 to the PUCCH demodulation and decoding unit 120.

[0055] The PUCCH demodulation / decoding unit 120 performs equalization, demodulation, decoding or power detection on the PUCCH signal inputted from the extraction unit 118 or the SR detection unit 119, and outputs the decoded bit sequence or the power detected signal to the decision unit 121.

[0056] Determination section 121 determines whether the HARQ-ACK signal transmitted from terminal 200 indicates an ACK or a NACK for the transmitted data signal, based on the bit sequence or the signal after power detection input from PUCCH demodulation and decoding section 120. Determination section 121 outputs the determination result to retransmission control section 104.

[0057] [Device configuration] Fig. 4 is a block diagram showing a configuration of terminal 200 according to embodiment 1 of the present disclosure. In Fig. 40, terminal 200 includes antenna 201, receiving section 202, FFT section 203, extracting section 204, downlink control signal demodulating section 205, higher level control signal demodulating section 206, downlink data signal demodulating section 207, error detecting section 208, control section 209, SR generating section 210, HARQ-ACK generating section 211, signal allocating section 212, IFFT section 213, and transmitting section 214.

[0058] The receiving unit 202 performs RF processing such as down-conversion or A / D (Analog-to-Digital) conversion on the signal waveform of the downlink signal (data signal and control signal) from the base station 100 received via the antenna 201, and outputs the resulting received signal (baseband signal) to the FFT unit 203.

[0059] FFT section 203 performs FFT processing on the signal (time domain signal) input from receiving section 202 to convert the time domain signal into a frequency domain signal. FFT section 203 outputs the frequency domain signal obtained by the FFT processing to extraction section 204.

[0060] Based on the control information input from the control unit 209, extraction unit 204 extracts a downlink control signal from the signal input from the FFT unit 203 and outputs the signal to the downlink control signal demodulation unit 205. Furthermore, extraction unit 204 extracts a higher-level control signal and a lower-level data signal based on the control information input from the control unit 209, outputs the higher-level control signal to the higher-level control signal demodulation unit 206, and outputs the lower-level data signal to the downlink data signal demodulation unit 207.

[0061] The downlink control signal demodulation unit 205 blind decodes the downlink control signal input from the extraction unit 204 , and if it determines that the control signal is addressed to the own device, demodulates the control signal and outputs it to the control unit 209 .

[0062] The higher-order control signal demodulation section 206 demodulates the higher-order control signal inputted from the extraction section 204 , and outputs the demodulated higher-order control signal to the control section 209 .

[0063] The downlink data signal demodulation unit 207 demodulates and decodes the downlink data signal inputted from the extraction unit 204 and outputs the decoded downlink data to the error detection unit 208 .

[0064] The error detection unit 208 performs error detection on the downlink data input from the downlink data signal demodulation unit 207, and outputs the error detection result to the HARQ-ACK generation unit 211. Furthermore, the error detection unit 208 outputs the downlink data determined to be error-free as a result of the error detection as received data.

[0065] The control unit 209 calculates a radio resource allocation for the downlink data signal based on the downlink resource allocation information indicated in the control signal input from the downlink control signal demodulation unit 205, and outputs information indicating the calculated radio resource allocation to the extraction unit 204.

[0066] Furthermore, control unit 209 calculates PUCCH resources for transmitting SR and HARQ-ACK based on PUCCH resource allocation information regarding PUCCH resource allocation for SR and HARQ-ACK, which is indicated in the higher level control signal input from higher level control signal demodulation unit 206 or the control signal input from downlink control signal demodulation unit 205. Then, control unit 209 outputs information regarding the calculated PUCCH resources to signal allocation unit 212.

[0067] Furthermore, control section 209 determines time-frequency resources and sequences for the PUCCH in which terminal 200 actually transmits SR and HARQ-ACK, using a method described later, and outputs the determined information to signal allocation section 212 and transmission section 214.

[0068] The SR generating unit 210 generates an SR when the terminal 200 requests the base station 100 to allocate radio resources for uplink transmission, and outputs the generated SR signal to the signal allocating unit 212.

[0069] The HARQ-ACK generation unit 211 generates a HARQ-ACK signal (ACK or NACK) for the received downlink data, based on the error detection result input from the error detection unit 208. The HARQ-ACK generation unit 211 outputs the generated HARQ-ACK signal (bit sequence) to the signal allocation unit 212.

[0070] The signal allocation unit 212 maps the SR signal input from the SR generation unit 210 or the HARQ-ACK signal input from the HARQ-ACK generation unit 211 to a radio resource instructed by the control unit 209. The signal allocation unit 212 outputs to the IFFT unit 213 an uplink signal (for example, uplink control information (UCI)) onto which the signal is mapped.

[0071] The IFFT unit 213 performs transmission waveform generation processing such as OFDM on the signal input from the signal allocation unit 212. In the case of OFDM transmission in which a CP (Cyclic Prefix) is added, the IFFT unit 213 adds a CP (not shown). Alternatively, in the case where the IFFT unit 213 generates a single carrier waveform, a DFT (Discrete Fourier Transform) unit may be added (not shown) before the signal allocation unit 212. The IFFT unit 213 outputs the generated transmission waveform to the transmission unit 214.

[0072] The transmitting unit 214 performs RF (Radio Frequency) processing such as transmission power control, D / A (Digital-to-Analog) conversion, and up-conversion on the signal input from the IFFT unit 213 based on information input from the control unit 209, and transmits a wireless signal to the base station 100 via the antenna 201.

[0073] [Operation of base station 100 and terminal 200] The operations of base station 100 and terminal 200 having the above configuration will now be described in detail.

[0074] FIG. 5 shows a flow of processing in terminal 200 according to this embodiment.

[0075] In this embodiment, the sequence number (sequence ID) of a PUCCH sequence (for example, a CG sequence) is determined using additional identification information (identification ID) in addition to the cell ID.

[0076] For example, the additional identification information may be information related to a subcell (e.g., a subcell ID for identifying a subcell), information related to a beam (e.g., a beam ID for identifying a beam) in a wireless communication system that applies beamforming, or information related to initial access (random access), etc. Hereinafter, the additional identification information is referred to as "subcell specific information" which is information specific to a subcell.

[0077] As shown in FIG. 6 described later, a "subcell" is, for example, a cell formed for one or more TRPs in one cell (see, for example, Non-Patent Document 4). A subcell can also be a cell formed for one or more beams formed in one cell (or TRP). When subbands having different numerologies are formed in a system band in one cell (or TRP), a subcell can also be a cell formed for each subband. A subcell can also be a cell set according to the coverage in the cell.

[0078] In addition, the information related to random access may be, for example, information about random access resources notified by a "PDCCH order" in which the network requests random access from terminal 200, or, when a random access procedure is initiated by terminal 200, information about the random access resources (time, frequency, code sequence) actually used by terminal 200.

[0079] The terminal 200 identifies the cell ID of the cell (base station 100) to which the terminal 200 belongs and the subcell specific information (ST101). For example, the terminal 200 identifies at least one of the subcell ID (the subcell ID of the subcell to which the terminal 200 is connected) corresponding to the TRP that communicates with the terminal 200, the beam ID of the beam that the terminal 200 uses for communication, and the information indicating the random access resource that the terminal 200 uses for communication.

[0080] Next, terminal 200 calculates identification information for calculating a sequence index of a PUCCH sequence (hereinafter referred to as an identification ID used for PUCCH) using the cell ID and subcell specific information (ST102). Then, terminal 200 determines a PUCCH resource (sequence index of a PUCCH sequence) based on the calculated identification ID used for PUCCH.

[0081] Then, terminal 200 allocates UCI (HARQ-ACK, SR, etc.) to the determined PUCCH resource (ST103), and transmits PUCCH to base station 100 (ST104).

[0082] As described above, in LTE, when the cell ID is different, the initial value of the random sequence that determines the hopping pattern of the PUCCH sequence is different. In the present embodiment, similarly to LTE, when the identification ID used for the PUCCH that is determined based on the cell ID and the subcell specific information is different, the initial value of the random sequence that determines the hopping pattern of the PUCCH sequence is different, and the PUCCH sequence is different.

[0083] In other words, if the sub-cell specific information corresponding to different TRPs in the same cell (i.e., when the same cell ID is used) is different, the identification IDs (values ​​determined based on the cell ID and the sub-cell specific information) for determining the sequence numbers of the PUCCH sequences used in communication with these different TRPs are different, and the sequence numbers of the PUCCH sequences can be made different.

[0084] Therefore, even in an environment where multiple TRPs are operated in the same cell, PUCCH sequences can be assigned based on different hopping patterns (different sequence numbers) between terminals 200 communicating with different TRPs. This makes it possible to prevent the same PUCCH sequence from colliding continuously in the PUCCHs transmitted from each terminal 200, or to prevent interference bias caused by multiple colliding sequences always being the same. In other words, interference can be randomized in the transmission of Short PUCCH, and the effect of interference can be reduced, thereby improving system performance.

[0085] Next, a specific example of a method for determining sequence index i of a PUCCH sequence allocated in a certain time unit n will be described.

[0086] Here, for example, sequence index i of the PUCCH sequence is determined according to equation (1). i = f(n) mod N sequence (1)

[0087] In equation (1), f(n) is a hopping pattern. f(n) is generated using a pseudorandom sequence, for example, as described in section 5.5.1.3 of Non-Patent Document 1. In addition, N sequence is the number of sequences prepared for PUCCH (for example, 30 in LTE).

[0088] The method of generating the pseudorandom sequence used to generate f(n) is, for example, specified in Section 7.2 of Non-Patent Document 1. The pseudorandom sequence is, for example, int In equation (2), the initial value c int If different, the pseudorandom sequence generated will be different.

number

[0089] In formula (2), n IDis the identification ID used for the PUCCH described above. ID ) may be notified to terminal 200 by terminal-specific higher layer signaling, and may be expressed as cell ID (n ID cell ) and subcell specific information (n ID subcell , n ID beam , n order RA , and n index RA may be set in the terminal 200 using at least one of the above. n ID = n ID cell + n ID subcell n ID = n ID cell + n ID beam n ID = n ID cell + n order RA n ID = n ID cell + n index RA

[0090] n ID subcell indicates the subcell ID, and n ID beam indicates the beam ID, and n order RA indicates information about random access resources notified in a PDCCH order in which the network requests random access to terminal 200, and n index RA indicates the number of a random access resource (time, frequency, code sequence) actually used by terminal 200. Furthermore, an identification ID used for a PUCCH may be set using a plurality of pieces of sub-cell specific information described above.

[0091] Examples of the time unit n for hopping the PUCCH sequence include a symbol unit, a slot unit, a subframe unit, etc. Examples of the time interval for initializing the pseudo-random sequence include a multiple symbol unit, a slot unit, a multiple slot unit, a subframe unit, a multiple subframe unit, a radio frame unit, etc.

[0092] 6, 7, and 8 show, as an example, how identification IDs used for PUCCH are set according to subcells, beams, and random access resources (RA resources), respectively.

[0093] As shown in FIG. 6, FIG. 7, and FIG. 8, the identification ID (n ID The cell ID used to set the cell ID (n ID cell A ).

[0094] For example, as shown in FIG. 6, the terminal 200 is connected to the subcell 1 (subcell ID: n ID subcell 1 ), TRP corresponding to subcell 2 (subcell ID: n ID subcell 2 ) and subcell 3 (subcell ID: n ID subcell 3 ), according to the TRP with which terminal 200 communicates, an identification ID (n ID In Figure 6, n ID (subcell1), n ID (subcell2), n ID (subcell3) are different values ​​from each other.

[0095] For example, as shown in FIG. 7, the terminal 200 is connected to the beam 1 (beam ID: n ID beam 1 ), Beam 2 (Beam ID: n ID beam 2 ), and beam 3 (beam ID: n ID beam 3), according to the beam used in communication between the terminal 200 and the TRP, an identification ID (n ID In Figure 7, n ID (beam1), n ID (beam2), n ID (beam3) are different values ​​from each other.

[0096] Also, for example, as shown in FIG. 8, the terminal 200 uses RA resource 1 (n ID RA1 ), RA Resource 2(n ID RA2 ), and RA resource 3(n ID RA3 ), the identification ID (n ID In Figure 8, n ID (RA1), n ID (RA2), n ID (RA3) are different values ​​from each other.

[0097] Furthermore, base station 100, like terminal 200, uses subcell specific information corresponding to the TRP with which terminal 200 communicates to identify a PUCCH resource (a PUCCH sequence number) to which a PUCCH transmitted from terminal 200 is assigned. Then, base station 100 receives the PUCCH (UCI) transmitted in the determined PUCCH resource.

[0098] As described above, in this embodiment, terminal 200 determines a sequence (PUCCH sequence) to be used for PUCCH according to UCI (ACK, NACK, SR, or the like), and transmits UCI using the PUCCH sequence. At this time, the PUCCH sequence is calculated using the cell ID of the cell to which terminal 200 belongs and sub-cell specific information. Specifically, the sub-cell specific information is used to calculate an initial value of a pseudo-random sequence used in a hopping pattern of sequence numbers of the PUCCH sequence.

[0099] For example, as shown in Figs. 6, 7, and 8, ID cell A Even in the above case, terminal 200 can determine a PUCCH sequence using subcell-specific information that is specific to the TRP (or subcell) with which terminal 200 communicates, thereby allocating different PUCCH resources to the PUCCHs transmitted from terminals 200 communicating with different TRPs in the same cell, thereby enabling them to be distinguished from each other.

[0100] Therefore, according to this embodiment, even in an environment where a plurality of TRPs are operated in the same cell, it is possible to randomize interference in the transmission of Short PUCCH, and to reduce the influence of interference. That is, according to this embodiment, it is possible to appropriately control interference in PUCCH including 1-2 bits of UCI.

[0101] (Embodiment 2) A base station and a terminal according to this embodiment have basic configurations in common with base station 100 and terminal 200 according to embodiment 1, and therefore will be described with reference to FIGS.

[0102] In the first embodiment, a method for setting sequence index i of a PUCCH sequence as a PUCCH resource determined based on subcell specific information has been described. In contrast, in the present embodiment, a method for setting a cyclic shift pattern of a PUCCH (PUCCH sequence) (i.e., mapping between each UCI (ACK / NACK, SR) and a sequence (cyclic shift)) as a PUCCH resource will be described.

[0103] In the present embodiment, similarly to the first embodiment, the cyclic shift pattern of the PUCCH is determined using sub-cell specific information in addition to the cell ID.

[0104] As in the first embodiment, the subcell specific information may be, for example, a subcell ID, a beam ID, or information related to initial access (random access), etc. As in the first embodiment, the information related to random access may be, for example, information related to random access resources notified by a "PDCCH order" in which the network requests terminal 200 to access randomly, or information related to random access resources (time, frequency, code sequence) actually used by terminal 200.

[0105] That is, terminal 200 identifies the cell ID of the cell (base station 100) to which terminal 200 belongs and sub-cell specific information (ST101 shown in FIG. 5), calculates identification information (identification ID to be used for PUCCH) for calculating a PUCCH sequence (cyclic shift pattern) using the cell ID and the sub-cell specific information (ST102 shown in FIG. 5), and determines a PUCCH resource (cyclic shift pattern of PUCCH) based on the calculated identification ID to be used for PUCCH. Then, terminal 200 allocates UCI (HARQ-ACK and / or SR) to the determined PUCCH resource (ST103 shown in FIG. 5), and transmits PUCCH to base station 100 (ST104 shown in FIG. 5).

[0106] As described above, in LTE, when the cell ID is different, the initial value of the random sequence that determines the hopping pattern used in the cyclic shift pattern of the PUCCH is different. In the present embodiment, similarly to LTE, when the identification ID used in the PUCCH, which is determined based on the cell ID and the subcell specific information, is different, the initial value of the random sequence that determines the above-mentioned hopping pattern is different, and the cyclic shift pattern is different.

[0107] That is, terminal 200 shifts the cyclic shift pattern used for PUCCH according to the sub-cell specific information corresponding to the TRP to be communicated. As a result, if the sub-cell specific information corresponding to different TRPs in the same cell (that is, when the same cell ID is used) is different from one another, the identification ID (a value determined based on the cell ID and the sub-cell specific information) for determining the cyclic shift pattern of the PUCCH used in communication with these different TRPs is different from one another, and the cyclic shift pattern can be made different.

[0108] Therefore, even in an environment where a plurality of TRPs are operated in the same cell, PUCCH sequences can be allocated based on different hopping patterns (different cyclic shift patterns) between terminals 200 communicating with different TRPs. This makes it possible to prevent the same cyclic shift patterns from colliding consecutively in the PUCCHs transmitted from each terminal 200, or to prevent interference bias caused by a plurality of colliding cyclic shift patterns always being the same. In other words, interference can be randomized in the transmission of Short PUCCH, and the effect of interference can be reduced, thereby improving system performance.

[0109] Next, a specific example of a method for determining a cyclic shift pattern of a PUCCH allocated in a certain time unit n will be described.

[0110] The cyclic shift pattern may be given as a cyclic shift offset, for example, as shown in Fig. 9 (in the case of 1-bit UCI) and Fig. 10 (in the case of 2-bit UCI). For example, the cyclic shift pattern on the right side of Fig. 9 is a pattern in which an offset of 2 has been added to the cyclic shift pattern on the left side of Fig. 9. Also, the cyclic shift pattern on the right side of Fig. 10 is a pattern in which an offset of 7 has been added to the cyclic shift pattern on the left side of Fig. 10.

[0111] The cyclic shift pattern of the PUCCH is generated using a pseudo-random sequence, for example, as shown in section 5.4 of Non-Patent Document 1. The method of generating the pseudo-random sequence is specified, for example, in section 7.2 of Non-Patent Document 1. Specifically, the pseudo-random sequence is generated by subtracting the initial value c int In equation (3), the initial value c int If different, the pseudorandom sequence generated will be different. c int =n ID (3)

[0112] In formula (3), n ID is the identification information used for the PUCCH described above. In equation (3), the identification ID (n ID ) may be notified to terminal 200 by terminal-specific higher layer signaling, and may be expressed as cell ID (n ID cell ) and subcell specific information (n ID subcell , n ID beam , n order RA , and n index RA may be set in the terminal 200 using at least one of the above. n ID = n ID cell + n ID subcell n ID = n ID cell + n ID beam n ID = n ID cell + n order RA n ID = n ID cell + n index RA

[0113] n IDsubcell indicates the subcell ID, and n ID beam indicates the beam ID, and n order RA indicates information about random access resources notified in a PDCCH order in which the network requests random access to terminal 200, and n index RA indicates the number of a random access resource (time, frequency, code sequence) actually used by terminal 200. Furthermore, an identification ID used for a PUCCH may be set using a plurality of pieces of sub-cell specific information described above.

[0114] Examples of the time unit n for hopping the PUCCH cyclic shift pattern include a symbol unit, a slot unit, a subframe unit, etc. Examples of the time interval for initializing the pseudo-random sequence include a multiple symbol unit, a slot unit, a multiple slot unit, a subframe unit, a multiple subframe unit, a radio frame unit, etc.

[0115] As described above, in this embodiment, terminal 200 determines a sequence (PUCCH sequence) to be used for PUCCH according to UCI (ACK, NACK, SR, or the like), and transmits UCI using the PUCCH sequence. At this time, the PUCCH sequence is calculated using the cell ID of the cell to which terminal 200 belongs and sub-cell specific information. Specifically, the sub-cell specific information is used to calculate an initial value of a pseudo-random sequence used for hopping of a cyclic shift pattern used in the PUCCH sequence.

[0116] For example, even in the same cell (same cell ID), terminal 200 can randomize interference with PUCCHs transmitted from terminals 200 communicating with different TRPs in the same cell by determining a cyclic shift pattern of a PUCCH sequence using subcell specific information specific to the TRP (or subcell) with which terminal 200 communicates, thereby reducing the effect of interference. That is, according to the present embodiment, interference can be appropriately controlled in a PUCCH including 1-2 bits of UCI.

[0117] Note that the cyclic shift pattern hopping described in this embodiment and the PUCCH sequence hopping (sequence hopping) described in the first embodiment may be used together. When cyclic shift pattern hopping and sequence hopping are used together, the time unit for applying sequence hopping and the time unit for applying cyclic shift hopping may be the same or different. For example, sequence hopping may be performed in slot units, and cyclic shift hopping may be performed in symbol units. Also, the time interval for initializing the pseudo-random sequence may be the same or different between sequence hopping and cyclic shift hopping. Also, the identification ID (n ID ) may be the same or different between sequence hopping and cyclic shift hopping. This allows different sequence numbers or different cyclic shift patterns to be assigned to PUCCHs transmitted from terminals 200 communicating with different TRPs in the same cell, thereby reducing the effect of interference.

[0118] (Embodiment 3) In the sequence selection method, in the case of 1-bit UCI, PUCCH resources (cyclic shift sequences) for transmitting ACK without SR, NACK without SR, ACK with SR, and NACK with SR are reserved in advance for each terminal. When sequences to be assigned to the same terminal exist in the same PRB, four PUCCH resources out of 12 PUCCH resources (cyclic shift sequences) that can be assigned to one PRB are assigned to one terminal.

[0119] Similarly, in the case of 2-bit UCI, PUCCH resources (cyclic shift sequences) for transmitting ACK / ACK without SR, ACK / NACK without SR, NACK / ACK without SR, NACK / NACK without SR, ACK / ACK with SR, ACK / NACK with SR, NACK / ACK with SR, and NACK / NACK with SR are secured for each terminal. Therefore, of the 12 PUCCH resources (cyclic shift sequences) that can be allocated to one PRB, 8 PUCCH resources are allocated to each terminal.

[0120] That is, theoretically, in one PRB, a maximum of 12 cyclic shift sequences can be used, and for example, in the case of 1-bit UCI, a maximum of 3 UEs can be multiplexed. However, in this case, since all 12 cyclic shift sequences are used, even if the above-mentioned cyclic shift hopping is applied, the effect of randomizing interference is reduced.

[0121] Therefore, in this embodiment, a method of reducing the influence of interference by limiting the maximum number of sequences (cyclic shifts) that can be assigned within one PRB will be described.

[0122] A base station and a terminal according to the present embodiment have basic configurations in common with base station 100 and terminal 200 according to the first and second embodiments, and therefore will be described with reference to FIGS.

[0123] FIG. 11A (in the case of 1-bit UCI) and FIG. 11B (in the case of 2-bit UCI) show examples of cyclic shift patterns when the maximum number of sequences (cyclic shifts) that can be assigned within one PRB is limited to eight.

[0124] As described above, in the case of 1-bit UCI, four PUCCH resources are allocated per terminal 200, so a maximum of two terminals are multiplexed in one PRB in Fig. 11A. Also, as described above, in the case of 2-bit UCI, eight PUCCH resources are allocated per terminal 200, so a maximum of one terminal is multiplexed in one PRB in Fig. 11B.

[0125] That is, in Fig. 11A and Fig. 11B, of the 12 cyclic shift sequences in one PRB, 4 cyclic shift sequences are not used for the PUCCH sequence. As a result, in the cyclic shift patterns shown in Fig. 11A and Fig. 11B, it is possible to space out the cyclic shift sequences used for the PUCCH sequence. Therefore, in this case, by applying the above-mentioned cyclic shift hopping, it becomes more likely that different cyclic shift sequences are assigned to PUCCHs transmitted from terminals 200 using different cyclic shift patterns, and it is possible to obtain the effect of randomizing interference.

[0126] Instead of limiting the maximum number of sequences to be allocated within one PRB (8 in Figs. 11A and 11B), the number of terminals to be allocated within one PRB may be limited. For example, in Fig. 11A, the maximum number of terminals that can be allocated within one PRB is limited to two terminals, and in Fig. 11B, the maximum number of terminals that can be allocated within one PRB is limited to one terminal.

[0127] Furthermore, the maximum number of sequences (cyclic shifts) that can be assigned within one PRB is not limited to 8, and for example, the number of terminals multiplexed may be limited to 1. In the case of a 1-bit UCI, the maximum number of sequences (cyclic shifts) that can be assigned within one PRB is 4 sequences, and in the case of a 2-bit UCI, the maximum number of sequences (cyclic shifts) that can be assigned within one PRB is 8 sequences.

[0128] In this way, according to the present embodiment, by limiting the maximum number of sequences (cyclic shifts) (or the number of terminals) that can be assigned to one PRB in a cyclic shift pattern, some cyclic shifts among the cyclic shifts in one PRB are not used as PUCCH sequences. Cyclic shifts that are not used as PUCCH sequences can be used for PUCCH sequences in different cyclic shift patterns. Therefore, it is possible to reduce PUCCH sequences that use the same cyclic shift pattern as PUCCH resources. As a result, according to the present embodiment, it is possible to further increase the effect of randomizing interference.

[0129] (Embodiment 4) In this embodiment, a mapping design between uplink control signals such as ACK, NACK, and SR and PUCCH (cyclic shift) will be considered.

[0130] In this embodiment, attention is paid to the difference in occurrence probability between ACK, NACK, and SR.

[0131] The target error rate for the initial packet transmission in downlink HARQ is, for example, about 10%. This means that, stochastically, the transmission (occurrence probability) of ACKs increases and the transmission (occurrence probability) of NACKs decreases. Therefore, stochastically, NACKs are likely to be adversely affected by ACKs transmitted from other terminals that are multiplexed with them.

[0132] 11A, when terminal 1 (UE1) transmits a NACK, terminal 2 (UE2) is likely to transmit an ACK based on the occurrence probability of ACK and NACK. Therefore, in the base station, the NACK transmitted from terminal 1 is likely to be erroneously received as an ACK mapped to a cyclic shift adjacent to the cyclic shift (i.e., corresponding to the ACK) that terminal 2 is likely to transmit.

[0133] In such a mapping method, even if a shift in the cyclic shift pattern as described in the second embodiment is applied, it is not possible to randomize the influence of interference between multiple terminals in a cell.

[0134] Therefore, in this embodiment, the mapping of ACK, NACK, and SR to PUCCH (cyclic shift) is made different between terminals in which ACK / NACK or SR is multiplexed. In this way, the influence of interference from multiple terminals occurring between cyclic shifts can be randomized.

[0135] A base station and a terminal according to this embodiment have basic configurations in common with base station 100 and terminal 200 according to embodiment 1, and therefore will be described with reference to FIGS.

[0136] 12A and 12B show an example of a mapping method between ACK, NACK, and SR and PUCCH (cyclic shift) in each of terminals 1 and 2 (UE1 and UE2) in which ACK / NACK or SR is multiplexed.

[0137] Specifically, in FIGS. 12A and 12B, the mapping for terminal 1 is the same as the mapping shown in FIG. 11A.

[0138] On the other hand, Fig. 12A shows cyclic shift patterns obtained by adding an offset of 3 to the cyclic shift patterns of ACK with SR, ACK without SR, NACK with SR, and NACK without SR for terminal 2 shown in Fig. 11A. Also, Fig. 12B shows cyclic shift patterns obtained by adding an offset of 6 (i.e., an offset of 3 to the cyclic shift patterns shown in Fig. 12A) to the cyclic shift patterns of ACK with SR, ACK without SR, NACK with SR, and NACK without SR for terminal 2 shown in Fig. 11A.

[0139] As a result, an ACK with a high occurrence probability is more likely to be mapped to a cyclic shift adjacent to a cyclic shift to which a NACK with a low occurrence probability is mapped. As a result, even if terminal 1 (UE1) transmits a NACK, for example, the base station is less likely to erroneously receive the NACK transmitted from terminal 1 as an ACK due to the ACK transmitted by terminal 2 with a high probability.

[0140] Next, another mapping method that takes into account the difference in occurrence probability of ACK, NACK, and SR will be described. Specifically, the hopping of the cyclic shift pattern described in the above-mentioned second embodiment is applied in consideration of the difference in occurrence probability of ACK, NACK, and SR.

[0141] For example, as shown in FIG. 13 or 14, an area including a cyclic shift assigned to an ACK (ACK area) and an area including a cyclic shift assigned to a NACK (NACK area) may be separated.

[0142] In this case, the hopping of the cyclic shift pattern is performed for each of the ACK and the NACK, that is, the cyclic shifts available for the ACK are cyclic shifts in the ACK region, and the cyclic shifts available for the NACK are cyclic shifts in the NACK region.

[0143] Also, as shown in FIG. 13 or 14, in the 12 cyclic shifts (0 to 11) that can be assigned to one PRB, the ratio of the ACK area may be set higher than the ratio of the NACK area.

[0144] By increasing the ratio of cyclic shifts that can be assigned to ACKs among the cyclic shifts that can be assigned within one PRB, the number of cyclic shift patterns for ACKs increases, thereby reducing the probability that an ACK that is highly likely to be transmitted will be transmitted in the same cyclic shift pattern from multiple terminals 200.

[0145] On the other hand, when the ratio of cyclic shifts that can be assigned to NACKs among the cyclic shifts that can be assigned within one PRB is reduced, the number of cyclic shift patterns for NACKs is reduced. However, since the probability of NACK transmission is low, the probability of NACKs being simultaneously transmitted in the same cyclic shift pattern from multiple terminals 200 is low, and the probability of PUCCHs including NACKs colliding with each other is low, so the impact on system performance is small.

[0146] As described above, according to this embodiment, by setting the mapping of the PUCCH sequence (cyclic shift) according to the occurrence probability of ACK and NACK transmitted using the PUCCH, it is possible to randomize interference in the transmission of Short PUCCH, and by reducing the effect of interference, it is possible to improve system performance.

[0147] (Embodiment 5) In this embodiment, a case will be described in which the hopping of the cyclic shift pattern described in the second embodiment is applied in consideration of the differences in the target error rates for ACK, NACK, and SR.

[0148] A base station and a terminal according to this embodiment have basic configurations in common with base station 100 and terminal 200 according to embodiment 1, and therefore will be described with reference to FIGS.

[0149] For example, as shown in FIGS. 15 and 16, an area including a cyclic shift to be assigned to an ACK (ACK area) is separated from an area including a cyclic shift to be assigned to a NACK (NACK area).

[0150] In this case, the hopping of the cyclic shift pattern is performed for each of the ACK and the NACK, that is, the cyclic shifts available for the ACK are cyclic shifts in the ACK region, and the cyclic shifts available for the NACK are cyclic shifts in the NACK region.

[0151] Also, as shown in FIGS. 15 and 16, in the 12 cyclic shifts (0 to 11) that can be assigned to one PRB, the ratio of the NACK area is set higher than the ratio of the ACK area.

[0152] By increasing the ratio of cyclic shifts that can be assigned to NACKs among the cyclic shifts that can be assigned within one PRB, the number of cyclic shift patterns for NACKs increases, so that it is possible to reduce the probability that NACKs with high requirements for the target error rate are transmitted in the same cyclic shift pattern from multiple terminals 200.

[0153] On the other hand, when the ratio of cyclic shifts that can be assigned to ACKs among the cyclic shifts that can be assigned within one PRB is reduced, the number of cyclic shift patterns for ACKs is reduced. However, even if ACKs with low target error rate requirements are transmitted from multiple terminals 200 using the same cyclic shift pattern and collision occurs between PUCCHs including ACKs, the impact on the system is smaller than that of NACKs.

[0154] As described above, according to this embodiment, by setting the mapping of the PUCCH sequence (cyclic shift) according to the target error rate (transmission reliability) of the ACK and NACK transmitted using the PUCCH, it is possible to randomize interference in the transmission of Short PUCCH, and by reducing the effect of interference, it is possible to improve system performance.

[0155] The embodiments of the present disclosure have been described above.

[0156] [Other embodiments] (1) In the above embodiment, SR and HARQ-ACK have been described as uplink control information (UCI) transmitted by terminal 200. However, the uplink control information transmitted by terminal 200 is not limited to SR and HARQ-ACK, and may be other uplink control information (for example, CSI, etc.).

[0157] (2) In the above embodiment, the identification ID (n ID In the above description, the sub-cell ID, the beam ID, and information related to random access are used as examples of identification information (sub-cell specific information) used in addition to the cell ID when calculating the identification ID used for PUCCH. However, the identification information used in addition to the cell ID when calculating the identification ID used for PUCCH is not limited to these pieces of information, and may be other information that can take different values ​​for each TRP. Furthermore, the identification information used in addition to the cell ID when calculating the identification ID used for PUCCH may be information set for the terminal 200 at the stage of initial access (random access).

[0158] (3) In the above embodiment, the Short PUCCH has been described. However, the above-described aspect of the present disclosure may be applied to a case where 1 to 2 bits of UCI are transmitted in the Long PUCCH.

[0159] (4) The present disclosure can be realized by software, hardware, or software linked to hardware. Each functional block used in the description of the above embodiment may be realized, in part or in whole, as an LSI, which is an integrated circuit, and each process described in the above embodiment may be controlled, in part or in whole, by one LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of one chip to include some or all of the functional blocks. The LSI may have input and output data. Depending on the degree of integration, the LSI may be called an IC, a system LSI, a super LSI, or an ultra LSI. The method of integration is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. In addition, a field programmable gate array (FPGA) that can be programmed after LSI manufacture, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells inside the LSI may be used. The present disclosure may be realized as digital processing or analog processing. Furthermore, if a new integrated circuit technology that can replace LSI appears due to the progress of semiconductor technology or a derivative technology, it is possible to integrate the functional blocks using that technology. The application of biotechnology is also a possibility.

[0160] A terminal of the present disclosure includes a circuit that determines a sequence to be used for an uplink control channel in response to uplink control information, and a transmitter that transmits the uplink control information using the sequence, and the sequence is determined using cell identification information that identifies a cell to which the terminal belongs, and sub-cell specific information for at least one sub-cell included in the cell.

[0161] In the terminal of the present disclosure, the sub-cell specific information includes at least one of information identifying a sub-cell to which the terminal is connected, information identifying a beam used by the terminal for communication, and information indicating a random access resource used by the terminal for communication.

[0162] In the terminal of the present disclosure, the sub-cell specific information is used to calculate an initial value of a pseudo-random sequence used for hopping the sequence number of the sequence.

[0163] In the terminal of the present disclosure, the sub-cell specific information is used to calculate an initial value of a pseudo-random sequence used for hopping of a cyclic shift pattern used in the sequence.

[0164] In the terminals of the present disclosure, the cyclic shift pattern differs for each terminal.

[0165] A terminal of the present disclosure includes a circuit that determines a sequence to be used for an uplink control channel in response to uplink control information, and a transmitter that transmits the uplink control information using the sequence, and limits the maximum number of the sequences that can be allocated within one resource block of the uplink control channel.

[0166] In the terminal of the present disclosure, the one resource block is composed of 12 subcarriers, and the maximum number is eight.

[0167] In the terminal of the present disclosure, one resource block is composed of 12 subcarriers, and the maximum number is 4 when the uplink control information is 1 bit, and 8 when the uplink control information is 2 bits.

[0168] A terminal of the present disclosure includes a circuit that determines a sequence to be used for an uplink control channel in response to uplink control information, and a transmitter that transmits the uplink control information using the sequence, where the uplink control information includes at least an ACK and a NACK, and a cyclic shift used in the sequence is separated into a first region that includes a cyclic shift assigned to the ACK and a second region that includes a cyclic shift assigned to the NACK.

[0169] In the terminal of the present disclosure, the number of cyclic shifts included in the first region is greater than the number of cyclic shifts included in the second region.

[0170] In the terminal of the present disclosure, the number of cyclic shifts included in the second region is greater than the number of cyclic shifts included in the first region.

[0171] In the terminal of the present disclosure, the hopping of the cyclic shift pattern for the ACK is performed using a cyclic shift included in the first region, and the hopping of the cyclic shift pattern for the NACK is performed using a cyclic shift included in the second region.

[0172] The communication method of the present disclosure determines a sequence to be used for an uplink control channel in accordance with uplink control information, and transmits the uplink control information using the sequence, where the sequence is determined using cell identification information that identifies a cell to which a terminal belongs, and sub-cell specific information for at least one sub-cell included in the cell.

[0173] The communication method of the present disclosure determines a sequence to be used for an uplink control channel in accordance with uplink control information, transmits the uplink control information using the sequence, and limits the maximum number of the sequences that can be allocated within one resource block of the uplink control channel.

[0174] A communication method of the present disclosure determines a sequence to be used for an uplink control channel in accordance with uplink control information, and transmits the uplink control information using the sequence, where the uplink control information includes at least an ACK and a NACK, and a cyclic shift used in the sequence is separated into a first region including a cyclic shift assigned to the ACK and a second region including a cyclic shift assigned to the NACK. [Industrial Applicability]

[0175] One aspect of the present disclosure is useful for mobile communication systems. [Explanation of symbols]

[0176] 100 base stations 101,209 Control section 102 Data Generation Department 103,107,110 Encoding section 104 Retransmission control section 105, 108, 111 Modulation section 106 Upper control signal generator 109 Downstream control signal generator 112,212 Signal allocation section 113,213 IFFT section 114,214 Transmitter 115,201 Antennas 116,202 Receiver 117,203 FFT section 118,204 Extraction part 119 SR detector 120 PUCCH demodulation and decoding unit 121 Judgment section 200 terminals 205 Downstream control signal demodulation section 206 Higher control signal demodulation section 207 Downstream data signal demodulation section 208 Error detection unit 210 SR generation section 211 HARQ-ACK generation section

Claims

1. A transmitter for transmitting information regarding a PUCCH resource to a terminal; A receiver receives uplink control information transmitted from the terminals by using a cyclic shift determined based on information set at an initial access stage according to uplink control information from among a plurality of cyclic shifts assignable to two terminals, the cyclic shifts being limited to a part of 12 cyclic shift sequences and based on information on the PUCCH resource; Equipped with Base station.

2. The number of the multiple assignable cyclic shifts is limited. The base station according to claim 1 .

3. the number of the assignable cyclic shifts is less than 12; A base station as claimed in claim 1 or 2.

4. The uplink control information is 1 bit or 2 bits. A base station according to any one of claims 1 to 3.

5. The uplink control information is transmitted on a Short PUCCH of one symbol or two symbols. A base station according to any one of claims 1 to 4.

6. The uplink control information includes at least one of an ACK and a NACK, and the cyclic shift is determined in response to at least one of the ACK and the NACK. A base station according to any one of claims 1 to 5.

7. each of the assignable cyclic shifts corresponds to at least one of an ACK and a NACK; Among the multiple assignable cyclic shifts, one of two adjacent cyclic shifts is associated with the ACK, and the other is associated with the NACK. A base station according to any one of claims 1 to 6.

8. Among the multiple assignable cyclic shifts, a cyclic shift assigned to one terminal is a cyclic shift assigned to another terminal plus a predetermined offset. A base station according to any one of claims 1 to 7.

9. a transmitter for transmitting information regarding the PUCCH resource; Equipped with The cyclic shift is determined based on information about the PUCCH resource. A base station according to any one of claims 1 to 8.

10. The cyclic shift is determined based on a terminal specific signal. A base station according to any one of claims 1 to 9.

11. transmitting information about a PUCCH resource to a terminal; receiving the uplink control information transmitted from the terminals by using a cyclic shift determined based on information set in an initial access stage according to uplink control information from among a plurality of cyclic shifts assignable to two terminals, the cyclic shifts being limited to a part of 12 cyclic shift sequences and based on information on the PUCCH resources; Equipped with Communication methods.

12. transmitting information about a PUCCH resource to a terminal; receiving the uplink control information transmitted from the terminals by using a cyclic shift determined based on information set in an initial access stage according to uplink control information from among a plurality of cyclic shifts assignable to two terminals, the cyclic shifts being limited to a part of 12 cyclic shift sequences and based on information on the PUCCH resources; Controlling Integrated circuits.

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