RU2788520C1 - Terminal and method for transmission - Google Patents

Abstract

FIELD: communication.

SUBSTANCE: invention relates to means of communication. The resource used to transmit a response signal to message B, said message being a response to the transmission of a random access signal, is determined. A first parameter indicating the resource in message B is transmitted to the communication terminal.

EFFECT: higher effectiveness of implementation of random access processes.

24 cl, 10 dwg

Description

Technical field

[0001] The present invention relates to a terminal and a transmission method.

State of the art

[0002] The 3rd Generation Partnership Project (3GPP) consortium has completed the specification for Edition 15 of the New Radio (NR) radio access technology for implementing 5G mobile communication systems. NR supports features for realizing Ultra Reliable and Low Latency Communication (URLC) combined with high speed and high bandwidth, which are the basic requirements for an enhanced mobile broadband network (Mobile Broadband, eMBB) (see. for example, non-patent literature (hereinafter referred to as "NPL" (Non-Patent Literature)) 1-7).

Link List

Non-Patent Literature

[0003] NPL 1

3GPP TS 38.211 V15.4.0, “NR; Physical channels and modulation (Release 15)" ("NR; Physical channels and modulation (Release 15)"), December 2018;

NPL 2

3GPP TS 38.212 V15.4.0, “NR; Multiplexing and channel coding (Release 15)” (“NR; Multiplexing and channel coding (Release 15)”), December 2018;

NPL 3

3GPP TS 38.213 V15.4.0, “NR; Physical layer procedure for control (Release 15), December 2018;

NPL 4

3GPP TS 38.214 V15.4.0, “NR; Physical layer procedures for data (Release 15)" December 2018

NPL 5

3GPP, TS38.300 V15.4.0, “NR; NR and NG-RAN overall description; Stage 2 (Release 15)" (NR; General description of NR and NG-RAN; Stage 2 (Release 15)"), December 2018

NPL 6

3GPP, TS38.321 V15.4.0, "NR; Medium access control (MAC) protocol specification (Release 15), December 2018

NPL 7

3GPP, TS38.331 V15.4.0, "NR; Radio resource control (RRC) protocol specification (Release 15), December 2018

NPL 8

B. Bertenyi, S. Nagata, H. Kooropaty, X. Zhou, W. Chen, Y. Kim, X. Dai, and X. Xu, “5G NR radio interface”, ICT Magazine , Volume 6 and 2, pp. 31-58, 2018.

NPL 9

RP-182881, "New work item: 2-step RACH for NR", ZTE Corporation, Sanechips, December 2018

Disclosure of the essence of the invention

[0004] However, random access processing has not been comprehensively studied.

[0005] In one non-limiting and exemplary embodiment of the present invention, a terminal and a transmission method are provided for improving the efficiency of random access data processing.

[0006] A terminal according to one embodiment of the present invention includes: a control circuit that, during operation, determines, based on a parameter configured for each of a plurality of terminals, a resource used for transmitting a response signal for a downlink signal addressed to a specified many terminals; and a transmission circuit that, during operation, transmits a response signal at the specified resource.

[0007] It should be noted that these general or specific aspects may be provided by a system, apparatus, method, integrated circuit, computer program, or storage medium, as well as by any combination of system, apparatus, method, integrated circuit, computer program, and carrier of information.

[0008] According to an exemplary embodiment of the present invention, the efficiency of random access processing can be improved.

[0009] Additional benefits and advantages of the disclosed exemplary embodiments will become apparent from the description of the invention and the drawings. Benefits and/or advantages may be separately obtained using the various embodiments and features presented in the description and drawings, which need not be provided all in order to obtain one or more of such benefits and/or advantages.

Brief description of the drawings

[0010]

in FIG. 1 shows an example of a 4-way random access procedure;

in FIG. 2 shows an example of a 2-stage random access procedure;

in FIG. 3 is a block diagram illustrating a configuration example of a terminal part according to Embodiment 1;

in FIG. 4 is a block diagram illustrating a configuration example of a base station according to Embodiment 1;

in FIG. 5 is a block diagram illustrating a configuration example of a terminal according to Embodiment 1;

in FIG. 6 is a flowchart illustrating an operation example of a base station and a terminal according to Embodiment 1;

in FIG. 7 shows an example of a 2-way random access procedure according to Embodiment 1;

in FIG. 8 shows another example of a 2-way random access procedure according to Embodiment 1;

in FIG. 9 shows an example configuration of message B; and

in FIG. 10 shows another example of message B configuration.

Implementation of the invention

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0012]

[Random access procedure]

In NR Release 15, a terminal (also referred to as a "mobile station" or "User Equipment" (User Equipment, UE)) transmits a random access signal (also referred to as a "Random Access Channel" (RACH) or "Physical RACH" (Physical RACH, PRACH) base station (also called "gNB" or "eNB"), for example, in the following cases:

(1) During initial access (eg, transition from the RRC_IDLE state to the RRC_CONNECTED state).

(2) When returning from the RRC_INACTIVE state to the RRC_CONNECTED state.

(3) When generating downlink or uplink data during a connection (eg, in the uplink synchronization state of "out of synchronization" in the RRC_CONNECTED state).

(4) When requesting system information (System Information, SI) on demand.

(5) When recovering from beam loss (Beam failure recovery, BFR)).

[0013] By transmitting a random access channel signal, an attempt is made to connect or recover synchronization by the terminal with the base station. The sequence of operations performed for such a connection or recovery of synchronization by the terminal with the base station is called the "random access procedure".

[0014] In NR Edition 15, the random access procedure consists of, for example, the four steps shown in FIG. 1 (referred to as "4-way random access procedure" or "4-way RACH procedure") (see, for example, NLT 8).

[0015] <Step 1: transmit message 1>

The terminal (e.g., UE) randomly selects for actual use a PRACH preamble resource from a set of potentially usable resources (e.g., resources indicated by a combination of time resources, frequency resources, and sequence resources) for a preamble signal (hereinafter referred to as "RACH preamble", "PRACH preamble or simply "preamble"). The terminal then transmits the PRACH preamble to the base station (eg, gNB) using the selected PRACH preamble resource. The PRACH preamble may be referred to as "message 1", for example.

[0016] <Step 2: message transmission 2>

Upon detection of a PRACH preamble, the base station transmits a RACH response (also referred to as a "Random Access Response" (RAR)). The RAR may be referred to as "message 2", for example. It should be noted that at this point, the base station cannot identify the terminal that transmitted the PRACH preamble. Thus, RAR is transmitted, for example, in the entire cell covered by the base station.

[0017] The RAR includes, for example, information about the resource (uplink resource) used by the terminal for transmitting the uplink signal (step 3: transmitting message 3) or transmission timing information for transmitting the uplink by the terminal. Meanwhile, when the terminal that transmitted the PRACH preamble does not receive RAR within a predetermined period (for example, called the RAR receive window) starting from the transmission timing of the PRACH preamble, the terminal again selects the PRACH preamble resource and transmits the PRACH preamble (in other words, retransmits the message 1).

[0018] <Step 3: Send Message 3>

The terminal transmits a "message 3" including, for example, a Radio Resource Control (RRC) connection request, a scheduling request, and the like using an uplink resource indicated by the base station via RAR.

[0019] <Step 4: message transmission 4>

The base station sends a message (referred to as "message 4") to the terminal including identification information (eg, UE ID) to identify the terminal. The base station transmits message 4 to confirm that there is no contention between the plurality of terminals (collision resolution). It should be noted that, for example, Cell-Radio Network Temporary Identifier (C-RNTI), temporary C-RNTI, and the like can be used as the UE identifier.

[0020] One example of a 4-stage random access procedure has been described above.

[0021] With regard to NR Edition 16, in order to efficiently connect or re-establish synchronization between a terminal and a base station with low latency, a two-stage random access procedure, such as those shown in FIG. 2 (which may also be referred to as "2-way random access procedure" or "2-way RACH procedure") (see, for example, NLT 9).

[0022] <Step 1: Message A transmission>

The terminal transmits to the base station a message (hereinafter referred to as "message A") including information corresponding to message 1 (in other words, preamble) and message 3 corresponding to step 1 and step 3 of the 4-way random access procedure (see, for example, FIG. 1).

[0023] <Step 2: transmit message B>

When message A is detected, the base station transmits message B. Message B includes, for example, information corresponding to message 2 or message 4 of the 4-way random access procedure (see, for example, FIG. 1) (for example, information from one or both from messages 2 and 4).

[0024]

[Retransmission control in random access procedure]

In the 4-round random access procedure, the transmission of message 2 is a multicast (or multicast) transmission. In message 2, for example, a Medium Access Control layer Protocol Data Unit (MAC PDU) includes a MAC RAR (or MAC subPDU) for one or more terminals. In addition, a Hybrid Automatic Repeat Request (HARQ), which is a retransmission control, is not applied to message 2.

[0025] In addition, in the 4-round random access procedure, the transmission of message 4 is unicast, and HARQ is applied to message 4.

[0026] On the other hand, in the 2-way random access procedure, message B includes: a MAC PDU including at least a RACH response (eg, RAR); and a MAC PDU including a message (eg, MAC CE for contention resolution) including identification information (eg, UE ID) for identifying the terminal.

[0027] For example, if message B transmission is unicast, as message 4 in the 4-way random access procedure, base station 100 schedules message B transmission for all random access terminals on a downlink control channel (e.g., physical channel downlink control (Physical Downlink Control Channel, PDCCH)). In this case, the resource consumption for the downlink control channel may increase with an increase in, for example, the number of terminals performing random access.

[0028] Accordingly, it is assumed that the multicast is applicable to the transmission of message B, as for message 2 in the 4-way random access procedure. Thus, resource consumption for the downlink control channel can be reduced.

[0029] In addition, in addition to the RAR-containing MAC PDU and the UE ID-containing MAC PDU described above, Message B may contain, for example, a MAC PDU containing a Radio Resource Control (RRC) signal. , relating to RRC connection, RRC reconnection, and RRC reconnection. If the MAC PDU including the RRC signal is included in message B, this can further reduce the delay in the 2-way random access procedure.

[0030] However, the amount of data in the RRC signal is large compared to other signals. Thus, it is assumed that the spectral efficiency of downlink resources is improved, for example, by applying HARQ to message B as well as to message 4 in the 4-way random access procedure. If HARQ is applied to Message B, the terminal sends a response signal (eg, Acknowledgment/Negative Acknowledgment (ACK/NACK)) indicating an error detection result of detecting downlink data (eg, RRC signal) to the base uplink station.

[0031] However, the transmission method of the ACK/NACK signal for message B transmitted by multicasting in the 2-way random access procedure has not been thoroughly considered.

[0032] For example, according to NR 15, resource allocation of an uplink control channel (e.g., a physical uplink control channel (Physical Uplink Control Channel, PUCCH)) (hereinafter referred to as PUCCH resources) was introduced for signal transmission ACK/NACK for message 4 (see, for example, NFL 3).

[0033] For example, using cell-specific higher layer signaling (e.g., Remaining Minimum System Information RMSI) such as a System Information Block (SIB), the base station indicates the resource configuration to the terminal in advance (eg, PUCCH resource set) indicating a combination of a plurality of parameters related to PUCCH resources. For example, according to NR 15, the PUCCH resource set includes 16 combinations of parameters related to PUCCH resources.

[0034] In addition, the base station selects from the set of PUCCH resources one combination of parameters related to the PUCCH resources actually used by the terminal, based on some bits within the PDCCH for which message 4 is scheduled (for example, 3 bits according to NR Revision 15), and based on the control channel element (CCE) number, which is the PDCCH resource allocation information.

[0035] For example, a _PUCCH combination r (eg, 16 combinations from 0th to 15th combinations) of parameters related to PUCCH resources can be given by the following equation:

[0036] In Equation 1, n _CCE is the CCE number, N _CCE is the number of CCEs, and Δ _PRI is a value (eg, any from 0 to 7) that is uniquely indicated by some bits (eg, 3 bits) of the PDCCH.

[0037] In this case, since the transmission of message 4 is a unicast, message 4 for each terminal is scheduled with a different PDCCH. Therefore, the PUCCH resources for the ACK/NACK signals for message 4 do not create a conflict between the terminals, for example, when the base station appropriately configures the combination of parameters related to the PUCCH resources indicated in equation 1 and _∆PRI indicated by the PDCCH.

[0038] At the same time, if the transmission of message B is a multicast, MAC PDUs for a plurality of terminals are included in the message B. Therefore, depending on the channel state for each terminal, there is a possibility that there are both terminals in the cell capable of correctly decode the MAC PDU, and terminals that are unable to decode the MAC PDU. In other words, the decoding result (in other words, the ACK/NACK signal) for the MAC PDU (eg, the MAC PDU including the RRC signal) in message B for each of the terminals may differ between terminals.

[0039] However, if the transmission of message B is multicast, the base station schedules one PDCCH for message B including MAC PDUs addressed to multiple terminals. For this reason, for example, when allocating a PUCCH resource for message 4 according to NR Edition 15 as defined in Equation 1, the same PUCCH resources are assigned to all terminals. Accordingly, when each of the terminals transmits the ACK/NACK signal corresponding to the decoding result for the MAC PDU in message B to the base station, all terminals transmit ACK/NACK signals using the same PUCCH resources. In other words, the PUCCH resources for ACK/NACK signals for message B may create a collision between terminals.

[0040] For example, if the base station transmits a PDCCH including Δ _PRI for each terminal (see, for example, Equation 1), PUCCH resource collision for ACK/NACK signals for message B between terminals can be reduced. However, in this case, the resource consumption of the PDCCH increases. For example, if it is assumed that _ΔPRI occupies 3 bits, according to NR edition 15, the resource consumption is: number of terminals (in other words, number of users) × 3 bits.

[0041] As a solution to the above, an exemplary embodiment of the present invention will be described with respect to a transmission method for transmitting an ACK/NACK signal for message B when transmission of message B is multicast in a 2-way random access procedure. According to an exemplary embodiment of the present invention, PUCCH resource collision between terminals can be reduced while reducing PDCCH resource consumption.

[0042] Hereinafter, embodiments of the present invention will be described in detail.

[0043] (Embodiment 1)

[Brief description of the communication system]

The communication system in accordance with each of the embodiments of the present invention includes a base station 100 and a terminal 200.

[0044] FIG. 3 is a block diagram illustrating a configuration example of a portion of a terminal 200 according to each of the embodiments of the present invention. In terminal 200 shown in FIG. 3, the controller 209 (corresponding to the control scheme), based on a parameter configured for each of the plurality of terminals, determines a resource used for transmitting a response signal (e.g., an ACK/NACK signal) for a downlink signal (e.g., message B) addressed to the plurality of terminals. terminals. Transmitter 218 transmits a response using the resource described above.

[0045]

[Base Station Configuration]

FIG. 4 is a block diagram illustrating a configuration example of a base station 100 according to Embodiment 1 of the present invention. FIG. 4, base station 100 includes a controller 101, a data generator 102, an encoder 103, a retransmission controller 104, a modulator 105, an upper control signal generator 106, an encoder 107, a modulator 108, a downlink control signal generator 109, an encoder 110, a modulator 111 , a signal distributor 112, an Inverse Fast Fourier Transform (IFFT) section 113, a transmitter 114, an antenna 115, a receiver 116, a Fast Fourier Transform (Fast Fourier Transform) section 117, an extractor 118, a detector 119 , demodulator 120 and decoder 121.

[0046] The controller 101 determines the information for transmitting message A by the terminal 200 (also referred to as "message A transmission parameter"), and outputs certain information to the extractor 118, demodulator 120, and decoder 121. In addition, the controller 101 outputs certain information to the generator 106 of the senior signal management. Information for transmitting message A may include, for example, information about PRACH preamble resources, PUSCH resources, PUSCH Transport Block Size (TBS), or MCS of message A.

[0047] In addition, the controller 101 determines the allocation of a radio resource (eg, downlink resources, MCS, etc.) for the downlink signal to transmit a data signal (eg, message B, etc.), a control signal over high level (eg, senior control signal) or downlink control information (eg, downlink control signal). The controller 101 outputs certain information (eg, including scheduling information) to the encoders 103, 107, and 110, the modulators 105, 108, and 111, and the signal distributor 112. In addition, the controller 101 outputs certain information to the downlink control signal generator 109 .

[0048] In addition, based on the decoding result of message A (e.g., control plane data (C-Plane) or user plane data (User Plane, UP)) received from the decoder 121, and the detection result of message A (e.g., PRACH preamble ) received from the detector 119, the controller 101 determines the information to be included in the message B, and outputs the determined information to the data generator 102.

[0049] In addition, the controller 101 determines information about the PUCCH resource used by the terminal 200 to transmit the ACK/NACK signal for message B. The controller 101 outputs certain information to the high control signal generator 106, the downlink control signal generator 109, the data generator 102 or extractor 118.

[0050] The data generator 102 generates an information bit sequence (in other words, downlink data) of a message B using the information to be included in the message B received from the controller 101, and outputs the generated information bit sequence to the encoder 103.

[0051] The encoder 103 performs error correction encoding on the sequence of information bits (data signal) received from the data generator 102 and outputs the encoded data signal to the retransmission controller 104 .

[0052] The retransmission controller 104 outputs the encoded data signal from the encoder 103 to the modulator 105 during initial transmission. In addition, the retransmission controller 104 stores the encoded data signal. In addition, when a NACK for the transmitted data signal is received from the decoder 121, the retransmission controller 104 outputs the corresponding stored data to the modulator 105. When an ACK is received for the transmitted data, the retransmission controller 104 deletes the corresponding stored data.

[0053] The modulator 105 modulates the data signal received from the controller 104 retransmission, and outputs the modulated data signal to the device 112 signal distribution.

[0054] The high control signal generator 106 generates a control information bit sequence (high control signal) using the control information received from the controller 101, and outputs the generated control information bit sequence (high control signal) to the encoder 107.

[0055] The encoder 107 performs error correction encoding on the sequence of control information bits received from the senior control signal generator 106 and outputs the encoded control signal to the modulator 108.

[0056] The modulator 108 modulates the control signal received from the encoder 107, and outputs the modulated control signal to the signal distributor 112.

[0057] The downlink control signal generator 109 generates a sequence of control information bits (a downlink control signal such as Downlink Control Information) using the control information supplied from the controller 101, and outputs the generated sequence of information control bits to the encoder 110. Accordingly, the downlink control information generator 109 is configured to scramble control information (eg, a Physical Downlink Control Channel (PDCCH)) for terminals that use identification information (eg, Random Access RNTI (Random Access-RNTI, RA-RNTI)) for all terminals, UE-specific identification information (eg, C-RNTI), or the like.

[0058] The encoder 110 performs error correction encoding on the control information bit sequence supplied from the downlink control signal generator 109 and outputs the encoded control signal to the modulator 111.

[0059] The modulator 111 modulates the control signal received from the encoder 110, and outputs the modulated control signal to the signal distributor 112.

[0060] Based on the information indicating the radio resources received from the controller 101, the signal distributor 112 compares with the radio resources the data signal received from the modulator 105, the senior control signal received from the modulator 108, or the downlink control signal received from the modulator 111 The signal distributor 112 outputs to the IFFT section 113 a downlink signal in which the specified signal is mapped.

[0061] The IFFT section 113 performs transmission signal generation processing such as Orthogonal Frequency Division Multiplexing (OFDM) on the signal received from the signal distributor 112 . In the case of OFDM transmission with the addition of a cyclic prefix (Cyclic Prefix, CP), IFFT section 113 adds a CP (not shown). IFFT section 113 outputs the generated signal to transmitter 114.

[0062] The transmitter 114 performs radio frequency (Radio Frequency, RF) processing, such as digital-to-analog (Digital-to-Analog, D/A) conversion, frequency upconversion, and the like, on the signal received from section 113 IFFT, and transmits a radio signal to terminal 200 via antenna 115.

[0063] The receiver 116 performs RF processing, such as down-conversion or analog-to-digital (A/D) conversion, on the uplink signal received from terminal 200 via antenna 115, and after receiving processing outputs the uplink signal to the FFT section 117 .

[0064] The FFT section 117 performs FFT processing on the uplink signal received from the receiver 116 to convert the signal in the time domain to a signal in the frequency domain. The FFT section 117 outputs the frequency domain signal obtained by the FFT processing to the extractor 118.

[0065] Based on the information received from the controller 101, the extractor 118 extracts from the signal received from the FFT section 117, the part of the radio resource through which the PRACH preamble is transmitted, or the part of the radio resource through which the PUSCH messages A are transmitted. The extractor 118 outputs to the detector 119 the extracted radio resource portion by which the PRACH preamble is transmitted, and outputs to the demodulator 120 the extracted radio resource portion by which another signal other than the PRACH preamble is transmitted (eg, PUSCH of message A). In addition, based on the information provided by the controller 101, the extractor 118 extracts the ACK/NACK signal for message B from the signal received from the FFT section 117 and outputs the ACK/NACK signal to the demodulator 120.

[0066] The detector 119 performs detection of the PRACH preamble in the part of the radio resource received from the extractor 118 that corresponds to the PRACH preamble. The detector 119 outputs the PRACH preamble detection result information to the controller 101.

[0067] Based on the information provided by the controller 101, the demodulator 120 demodulates the message A data or the ACK/NACK signal for the message B received from the extractor 118, and outputs the demodulation result (demodulation sequence) to the decoder 121.

[0068] Based on the information from the controller 101, the decoder 121 performs error correction decoding on the demodulation result from the demodulator 120 and outputs a decoded bit sequence (including, for example, UCI, control plane data, or UP data). For example, decoder 121 also outputs the decoding result of message A to controller 101.

[0069] In addition, the decoder 121 decodes the ACK/NACK signal for message B based on the demodulation result from the demodulator 120, and determines whether the ACK/NACK signal for the transmitted data signal is ACK or NACK. The decoder 121 outputs the result of said determination (ACK or NACK) to the retransmission controller 104 .

[0070]

[Terminal configuration]

FIG. 5 is a block diagram illustrating a configuration example of a terminal 200 according to one embodiment of the present invention. FIG. 5, terminal 200 includes an antenna 201, receiver 202, FFT section 203, extractor 204, demodulator 205, decoder 206, downlink control signal demodulator 207, decoder 208, controller 209, PRACH preamble generator 210, ACK/NACK generator 211, encoder 212, modulator 213, encoder 214, modulator 215, signal distributor 216, IFFT section 217, and transmitter 218.

[0071] The receiver 202 performs RF processing, such as down-converting, analog-to-digital (A/D) conversion, or the like, on the downlink signal from the base station 100 received by the antenna 201, and outputs the received the received signal (baseband signal) to the FFT section 203 . The downlink signal includes, for example, a data signal (eg, message B or the like), a senior control signal, or a downlink control signal.

[0072] The FFT section 203 performs FFT processing on the downlink signal (time domain signal) received from the receiver 202 to convert the time domain signal into a frequency domain signal. The FFT section 203 outputs the frequency domain signal obtained by the FFT processing to the extractor 204.

[0073] Based on the control information (eg, radio resource information for the control signal) received from the controller 209, the extractor 204 extracts a data signal (eg, message B or the like), a downlink control signal, or an older control signal from signal received from section 203 FFT. The extractor 204 outputs the data signal or the senior control signal to the demodulator 205 and outputs the downlink control signal to the demodulator 207 of the downlink control signal.

[0074] The demodulator 205 demodulates the data signal or the senior control signal received from the extractor 204 and outputs the demodulation result to the decoder 206.

[0075] The decoder 206 performs error correction decoding using the demodulation result from the demodulator 205 to obtain received data (eg, message B) or control information. The decoder 208 outputs the received received data or control information to the controller 209. In addition, the decoder 206 performs error detection on the received data and outputs an error detection result (eg, the presence or absence of an error) to the ACK/NACK generator 211 .

[0076] The downlink control signal demodulator 207 demodulates the downlink control signal received from the extractor 204 and outputs the demodulation result to the decoder 208.

[0077] The decoder 208 performs error correction decoding using the demodulation result from the demodulator 207 of the downlink control signal to obtain control information. The decoder 208 outputs the received control information to the controller 209.

[0078] The controller 209 determines a parameter related to the uplink transmission (eg, message A transmission) based on the control information received from the decoder 206 or the decoder 208. The controller 209 outputs the determined information to the PRACH preamble generator 210, encoders 212 and 214, modulators 213 and 215, and a signal distributor 216.

[0079] In addition, the controller 209 determines ACK/NACK signaling information (e.g., uplink resource, transmission method, parameter, or the like) based on the ACK/NACK signaling resource information for message B, which comes from decoder 206 or decoder 208. Controller 209 outputs certain information to encoder 212, modulator 213, and signal distributor 216.

[0080] The controller 209 also outputs to the extractor 204 the radio resource information for the control signal, which is included in the control information received from the decoder 206 or the decoder 208.

[0081] The PRACH preamble generator 210 generates a PRACH preamble based on the control information (eg, message transmission parameter A) received from the controller 209, and outputs the generated PRACH preamble to the signal distributor 216 .

[0082] Based on the error detection result from the decoder 206, the ACK/NACK generator 211 generates an ACK/NACK signal for the received downlink data (e.g., message B) and outputs an ACK/NACK signal (e.g., an ACK/NACK signal sequence ) to encoder 212.

[0083] Based on the information received from the controller 209 (for example, information about the transmission of the ACK/NACK signal), the encoder 212 performs error correction encoding for the ACK/NACK signal sequence received from the ACK/NACK generator 211, and outputs the encoded signal sequence ACK/NACK to modulator 213.

[0084] Based on the information received from the controller 209, the modulator 213 modulates the ACK/NACK signal sequence received from the encoder 212 and outputs the modulated ACK/NACK signal sequence (modulation symbol sequence) to the signal distributor 216 .

[0085] Based on the control information (for example, message transmission parameter A) received from the controller 209, the encoder 214 performs error correction encoding, for example, for a sequence of information bits (for example, control plane data and UP data) to be transmitted in part as message data A, and outputs the encoded bit sequence to the modulator 215.

[0086] Based on the information received from the controller 209, the modulator 215 modulates the bit sequence received from the encoder 214, and outputs a data signal (sequence of modulation symbols) to the signal distributor 216 .

[0087] The signal distributor 216 matches the radio resources specified by the controller 209 with the signal from the PRACH preamble generator 210, the signal from the modulator 213, or the signal from the modulator 215, and outputs to the IFFT section 217 the uplink signal, with which the specified signal is associated.

[0088] The IFFT section 217 performs transmission signal generation processing, such as OFDM, on the signal received from the signal distributor 216 . In the case of OFDM transmission with CP addition, IFFT section 217 adds CP (not shown). In an alternative embodiment, if the IFFT section 217 generates a single carrier signal, a Discrete Fourier Transform (DFT) section (not shown) may be added before the signal distributor 216 . IFFT section 217 outputs the generated transmit signal to transmitter 218.

[0089] The transmitter 218 performs RF processing such as D/A conversion, upconversion, and/or the like on the signal received from the IFFT section 217, and transmits the radio signal to the base station 100 via the antenna 201.

[0090]

[Operation example of base station 100 and terminal 200]

Next, an operation example of the base station 100 and the terminal 200 having the above configurations will be described.

[0091] FIG. 6 shows an example of a flow related to transmission and reception processing for transmitting and receiving an ACK/NACK signal for a message B between the base station 100 and the terminal 200 according to the present embodiment.

[0092] As shown in FIG. 6, the base station 100 indicates to the terminal 200 the uplink resource information (eg, the PUCCH resource), for example (ST101). The PUCCH resource information includes, for example, PUCCH resource information for transmitting an ACK/NACK signal for message B. Terminal 200 obtains PUCCH resource information (ST102).

[0093] The base station 100 transmits to the terminal 200 scheduling information including, for example, allocation information for message B (ST103). The scheduling information for message B may be transmitted, for example, using the PDCCH. Terminal 200 receives scheduling information for message B (ST104).

[0094] The base station 100 transmits message B to terminal 200 based on, for example, scheduling information for message B (ST105).

[0095] When receiving a B message, the terminal 200 demodulates and decodes the B message (ST106). In addition, terminal 200 generates an ACK/NACK signal for message B.

[0096] Based on at least one of, for example, PUCCH resource information, scheduling information (eg, PDCCH), and message B (eg, RAR), terminal 200 determines an uplink resource for transmitting an ACK/NACK signal for message B (eg RRC signal) (ST107).

[0097] Then, the terminal 200 transmits an ACK/NACK signal for the message B to the base station 100 using the determined resource (ST108) of the uplink.

[0098]

[Transmission method of ACK/NACK signal for message B]

Next, an example of the ACK/NACK signal transmission method for message B will be described.

[0099] In the present embodiment, terminal 200, for example, transmits an ACK/NACK signal for message B on PUCCH.

[0100] Wherein, terminal 200 determines a PUCCH resource for transmitting an ACK/NACK signal for message B, for example, based on an indication (for example, a parameter given by Equation 1) of a PUCCH resource for transmitting an ACK/NACK signal for message 4 in 4- step-by-step random access procedure, and, in addition, based on the new parameter "X". The parameter X may be, for example, a value configured for each of the plurality of terminals 200 to which transmission of message B is addressed.

[0101] Next, Operation Example 1 and Operation Example 2 in the 2-step RACH procedure in the present embodiment will be described first.

[0102] Here, the case where three terminals 200 (eg, UE #A, UE #B, and UE #C) transmit message A to base station 100 (eg, gNB) will be described as an example.

[0103]

[Example 1 work]

FIG. 7 shows an example of a 2-stage random access procedure according to Operation Example 1.

[0104]<Message A transmission>

Each of the terminals 200 transmits message A to the base station 100.

[0105] Message A includes, for example, a RACH preamble (eg, one of preambles #1 to #3) and PUSCH (eg, a data part or a UCI+ data part). In addition, the PUSCH includes, for example, a UE ID for identifying the terminal 200 (eg, one of UE ID #A, UE ID #B, and UE ID #C).

[0106] In addition, when timing the transmission of the RACH preamble (in other words, message A), each terminal 200 operates with a "message B receive window" (in other words, with a timer), which is the period during which message B can be received. .

[0107]<Transmit Message To>

Upon detecting message A transmitted by each of terminals 200 and successfully decoding message A correctly, base station 100 transmits message B. Message B includes, for example, a message (e.g., MAC RAR and MAC CE) containing RAR and a UE ID to identify terminal 200 .

[0108] At the same time, if message A (eg, PRACH preamble) cannot be detected or message A (eg, PUSCH) cannot be correctly decoded, base station 100 does not include in message B information addressed to terminal 200 that transmitted the corresponding message. AND.

[0109] For example, in the example illustrated in FIG. 7, the base station (gNB) 100 detects preamble #1 of message A transmitted by UE #A (detection result: SUCCESS) and correctly decodes the PUSCH (decode result: SUCCESS). At the same time, the base station (gNB) 100 detects preamble #2 of message A transmitted by UE #B (detection result: SUCCESS), but it fails to decode the PUSCH correctly (decode result: FAILED). In addition, the base station (gNB) 100 fails to detect preamble #1 of message A transmitted by UE #C (detection result: FAILED) and fails to properly decode the PUSCH (decode result: FAILURE).

[0110] Thus, in the example illustrated in FIG. 7, the base station 100 generates a message B containing the RAR for UE #A and the UE ID #A of UE #A. In other words, in FIG. 7, message B does not include information addressed to UE #B and UE #C.

[0111]<Receive message B>

If a message B containing information addressed to the terminal 200 that sent the message A is not received, the terminal 200 that sent the message A retransmits the message A within the window period for receiving message B (in other words, restarts the random access process with message A). In the example shown in FIG. 7, UE #B and UE #C do not receive message B addressed to UE #B and UE #C during the receive window period of message B and retransmit message A accordingly.

[0112] On the other hand, if the terminal 200 that transmitted the message A receives a message B containing information addressed to the corresponding terminal 200 during the receive window period of the message B, and if the UE ID included in the message B matches the UE ID included in the transmitted message A, the terminal determines the execution of the RACH procedure as successful. In the example shown in FIG. 7, UE #A receives message B addressed to UE #A during the message reception window period B, and the UE ID (UE ID #A) included in message B matches the UE ID (UE ID #A) included in the transmitted message. message A. Accordingly, UE #A determines the execution of the RACH procedure as successful (RA procedure: SUCCESS).

[0113]<Job Example 2>

FIG. 8 shows an example of a 2-step RACH procedure according to Operation Example 2.

[0114]<Message A Transmission>

Each of the terminals 200 transmits message A to the base station 100.

[0115] As in Operation Example 1, message A includes, for example, a RACH preamble (eg, any of preambles #1 to #3) and PUSCH (eg, a data part or a UCI+ data part). In addition, the PUSCH includes, for example, a UE ID for identifying terminal 200 (eg, any of UE ID #A, UE ID #B, and UE ID #C).

[0116] In addition, when timing the transmission of the RACH preamble (in other words, message A), each terminal 200 operates with a "message B receive window" (in other words, with a timer), which is a period during which message B can be received. .

[0117]<Transmit Message To>

Upon detecting message A transmitted by each of terminals 200 and successfully decoding message A correctly, base station 100 transmits message B. Message B includes, for example, a message (e.g., MAC RAR and MAC CE) containing RAR and a UE ID to identify terminal 200 .

[0118] The base station 100 also transmits message B when the RACH preamble of message A transmitted by each of the terminals 200 is detected but fails to correctly decode the data part. If the base station 100 detects the RACH preamble but fails to correctly decode the data part, the base station 100 cannot identify the terminal 200 that transmitted the RACH preamble at that moment. Thus, in this case, for example, message B includes RAR (in other words, the UE ID is not included). For example, with respect to the terminal 200 that transmitted the corresponding RACH preamble, the RAR may contain retransmission request information for the data part and information about the resources used in the uplink.

[0119] On the other hand, if the message A (e.g., the PRACH preamble) cannot be detected, the base station 100 does not include in the message B information addressed to the terminal 200 that sent the corresponding message A.

[0120] For example, in the example illustrated in FIG. 8, as in the operation example 1 (for example, FIG. 7), the base station 100 (gNB) detects the preamble #1 of the message A transmitted by the UE #A (detection result: SUCCESS), and correctly decodes the PUSCH (decode result: SUCCESS) . At the same time, the base station (gNB) 100 detects preamble #2 of message A transmitted by UE #B (detection result: SUCCESS), but it fails to decode the PUSCH correctly (decode result: FAILED). In addition, the base station (gNB) 100 fails to detect preamble #1 of message A transmitted by UE #C (detection result: FAILED) and fails to properly decode the PUSCH (decode result: FAILURE).

[0121] Thus, in the example shown in FIG. 8, base station 100 generates message B including RAR for UE #A, UE ID #A, and RAR for UE #B. In other words, as shown in FIG. 7, message B does not include information addressed to UE #C.

[0122]<Receive message B>

If a message B containing information addressed to the terminal 200 that sent the message A is not received, the terminal 200 that sent the message A retransmits the message A within the window period for receiving message B (in other words, restarts the random access process with message A). In the example shown in FIG. 8, UE #C does not receive message B addressed to UE #C during the receive window period of message B, and accordingly retransmits message A.

[0123] On the other hand, if the terminal 200 that transmitted the message A receives a message B containing information addressed to the corresponding terminal 200 during the message reception window period B, but the UE ID included in the message B does not match the UE ID included in the transmitted message A, the terminal performs uplink transmission according to the information included in the RAR corresponding to message A (eg, the PRACH preamble). In the example shown in FIG. 8, UE #B receives a message B (eg, RAR) addressed to UE #B during the message reception window period B, but the UE ID (UE ID #A) included in the message B does not match the UE ID (UE ID #B). ) included in the transmitted message A. Accordingly, UE #B determines the execution of the RACH procedure as failed (RA procedure: FAILED). UE #B may retransmit the PUSCH based on, for example, the information included in the RAR for UE #B in message B. In other words, UE #B may perform message 3 transmission of the 4-way random access procedure.

[0124] In addition, if the terminal 200 that transmitted the message A receives a message B containing information addressed to the corresponding terminal 200 during the message reception window period B, and if the UE ID included in the message B matches the UE ID included in the transmitted message A, the terminal determines the execution of the RACH procedure as successful. In the example shown in FIG. 8, UE #A receives a message B addressed to UE #A during the message reception window period B, and the UE ID (UE ID #A) included in the message B corresponds to the UE ID (UE ID #A) included in the transmitted message. A. Accordingly, UE #A determines that the execution of the RACH procedure is successful (RA procedure: SUCCESSFUL).

[0125] Examples 1 and 2 have been described above for the operation of the 2-step random access procedure.

[0126] As described above, if base station 100 detects and correctly decodes message A, message B includes a MAC PDU including RAR and a MAC PDU including a message (e.g., MAC CE for contention resolution) including includes a UE identifier to identify terminal 200.

[0127] In addition, the MAC PDU including RAR may, for example, contain uplink signal transmission timing information for terminal 200, temporary C-RNTI (TC-RNTI), or resource information used by terminal 200 in uplink communication lines.

[0128] In addition to a MAC PDU including RAR and a MAC PDU including a UE ID, Message B may, for example, include a MAC PDU including an RRC signal for RRC connection, RRC reconnection, and reconnection. RRC.

[0129] FIG. 9 and 10 illustrate message B configuration examples. FIG. 9 shows an example in which a MAC PDU including an RRC signal is not included in message B, while in FIG. 10 shows an example in which a MAC PDU including an RRC signal is included in message B.

[0130] For example, if the terminal 200 receives a message B including information addressed to the terminal 200, if the UE ID included in the message B matches the UE ID included in the transmitted message A, and if the message B includes a MAC PDU, including the RRC signal addressed to the terminal 200, the terminal 200 decodes the MAC PDU including the RRC signal and transmits an ACK/NACK signal corresponding to the decoding result (or error detection result) to the base station 100 in the specified uplink resource ( e.g. PUCCH resource).

[0131] Next, a method for determining PUCCH resources for transmitting an ACK/NACK signal will be described.

[0132] For example, using cell-specific higher layer signaling (e.g., RMSI) such as SIB, base station 100 indicates to terminal 200 a resource configuration (e.g., PUCCH resource set) in advance by indicating a combination of a plurality of parameters related to PUCCH resources. For example, according to NR 15, the PUCCH resource set includes 16 combinations of parameters related to PUCCH resources. It should be noted that the number of combinations of parameters related to the PUCCH resources included in the PUCCH resource set is not limited to 16, and may be any other number.

[0133] In addition, the base station 100 selects from the set of PUCCH resources one combination of parameters related to the PUCCH resources actually used by the terminal 200, based on some bits within the PDCCH for which message B is scheduled (for example, 3 bits according to NR Revision 15 ), based on the PDCCH CCE number and based on additional information "X" indicating.

[0134] For example, the _PUCCH combination r (eg, 16 combinations from the 0th to the 15th combination) of parameters related to PUCCH resources can be given by the following equation:

[0135] In Equation 2, n _CCE is the CCE number, N _CCE is the number of CCEs, and Δ _PRI is a value (eg, any from 0 to 7) that is uniquely indicated by 3 bits of the PDCCH. It should be noted that _ΔPRI is not limited to 3 PDCCH bits and may correspond to other number of bits.

[0136] As described above, the terminal 200 determines the uplink resources to be used for transmitting the ACK/NACK signal based on, for example, a value related to the message B indicated by the PDCCH (e.g., Δ _PRI ), the resource to which the PDCCH (eg, n _CCE ), and a parameter "X" configured for each terminal 200. In other words, terminal 200 determines PUCCH resources for signaling ACK/NACK for message B based on a method (eg, see Equation 2) other than from a method (eg, see Equation 1) to determine PUCCH resources for ACK/NACK signaling for message 4, eg, a 4-round random access procedure.

[0137] In Equation 2, the parameter "X" may be indicated by the base station 100 to the terminal 200 explicitly or implicitly, for example, in the following ways (any of options 1-5 or a combination thereof).

[0138]<Option1>

The "X" parameter may be included in the MAC RAR of the message B (in other words, the response information of the message A (PRACH preamble)).

[0139] The MAC PDU including the RAR may contain, in addition to the "X" parameter, uplink transmission timing information for the terminal 200, TC-RNTI, or resource information used by the terminal 200 in the uplink.

[0140]<Option2>

The "X" parameter may be associated with a UE ID included in message A sent by terminal 200.

[0141] For example, the association may be such that X = UE ID mod Y. In this case, Y is the number of combinations of a set of parameters related to PUCCH resources included in the PUCCH resource set, and Y=16 according to NR 15.

[0142]<Option3>

The "X" parameter may be a value associated with the order (e.g., called "RAR order") of the RAR corresponding to the set of terminals 200 in message B.

[0143] For example, message B illustrated in FIG. 10, includes RAR in the following order: MAC subPDU3A, MAC subPDU4A,

[…]. In addition, in message B shown in FIG. 10, an RRC signal addressed to terminal 200 corresponding to the MAC subPDU3A is included in the MAC subPDU3C, and an RRC signal addressed to the terminal 200 corresponding to the MAC subPDU4A is included in the MAC subPDU4C.

[0144] In this case, for example, based on the order in which the RARs are included in the message B (position order), X=0 may be configured for the terminal 200 corresponding to the MAC subPDU3C (eg, the first RAR), X=1 may be configured for the terminal 200 corresponding to the subPDU4C MAC (eg, the second RAR). It should be noted that the number of RARs included in Message B and the X values associated with the order of the RARs are not limited to the above values.

[0145]<Option4>

The "X" parameter may be a value associated with the RACH preamble number (eg, PAID) used in message A sent by terminal 200.

[0146] For example, the association may be such that X=PAID mod Y. In this case, Y is the number of combinations of a set of parameters related to PUCCH resources included in the PUCCH resource set, and Y=16 according to 15 NR.

[0147]<Option5>

The "X" parameter may be a value associated with the port number (e.g., DMRS port number) of the PUSCH reference signal (e.g., demodulation reference signal (DMRS)) used in message A transmitted by terminal 200.

[0148] For example, the association may be such that X=DMRS port index mod Y. In this case, Y is the number of combinations of the parameter set related to PUCCH resources included in the PUCCH resource set, and Y=16 according to 15 NR.

[0149] Methods for specifying (options 1-5) the parameter "X" have been described above.

[0150] In accordance with the above five options, the parameter "X" is indicated to the terminal 200 without increasing the resource consumption of the PDCCH.

[0151] In addition, for example, according to Equation 2 including the "X" parameter, each terminal 200 may select a combination of r _PUCCH parameters related to PUCCH resources for each terminal 200. In other words, the terminal 200 may separately determine based on parameter "X" configured for each terminal 200, PUCCH resources for transmitting an ACK/NACK signal for message B (in other words, a signal addressed to a plurality of terminals 200) transmitted using multicast. Thus, PUCCH resource collision between terminals 200 can be reduced when ACK/NACK signaling for message B (eg, RRC signal) is signaled.

[0152] Therefore, according to the present embodiment, even if message B (for example, including RRC signals) is transmitted using multicast, PUCCH resource collision between terminals 200 can be reduced in ACK/NACK signaling for RRC signals without increasing the resource consumption of the PDCCH. Thus, in the present embodiment, the efficiency of random access processing (eg, retransmission control) for message B in the 2-way random access procedure can be improved.

[0153] It should be noted that any of the above options 1-5 may be applied, or a combination of a plurality of these options may be applied.

[0154] In addition, the present embodiment is not limited to the case where the terminal 200 determines the PUCCH using multiple PDCCH bits for which message B is scheduled (for example, 3 bits according to NR 15), a CCE number that is resource allocation information PDCCH, and, in addition, the "X" parameter. For example, terminal 200 may determine the PUCCH resources using the "X" parameter without using multiple PDCCH bits for which message B is scheduled and a CCE number. In this case, the resource consumption for the PDCCH can be further reduced.

[0155] In addition, if multiple multicast and unicast transmission methods are supported for message B, terminal 200 may determine PUCCH resources depending on the transmission method for message B. For example, terminal 200 determines PUCCH resources using the "X" parameter if the message B is configured for multicast (see, for example, equation 2), and terminal 200 may determine PUCCH resources without using the "X" parameter if unicast is configured (see, for example, equation 1).

[0156] (Embodiment 2)

Since the base station and the terminal according to the present embodiment have the same basic configurations as the base station 100 and the terminal 200 according to Embodiment 1, they will be described with reference to FIG. 4 and 5.

[0157] In the present embodiment, terminal 200 transmits an ACK/NACK signal for message B on an uplink control channel (eg, PUCCH).

[0158] Wherein, the base station 100 indicates to the terminal 200 the PUCCH resources for transmitting the ACK/NACK signal using, for example, the uplink assignment information (e.g., referred to as "UL Grant") included in the RAR of message B. The terminal 200 determines the resources PUCCH for transmitting an ACK/NACK signal for message B (e.g., an RRC signal) based on, for example, granting a UL included in the RAR of message B addressed to terminal 200.

[0159] For example, in example 2 of operation of the 2-way random access procedure in Embodiment 1 (see, for example, FIG. 8), base station 100 transmits message B when message A is detected and correctly decoded. Wherein, message B includes a message, including a RAR and a UE identifier for identifying the terminal 200.

[0160] In the present embodiment, upon detecting and correctly decoding message A, base station 100 indicates, in the UL grant included in RAR, uplink resources (e.g., PUCCH resources) to transmit an ACK/NACK signal for message B (e.g., RRC signal ). For example, if terminal 200 receives message B including information addressed to terminal 200, if the UE identifier included in message B matches the UE identifier transmitted in message A, and if message B includes a MAC PDU including signal RRC addressed to terminal 200, terminal 200 decodes the MAC PDU and transmits the decoding result (eg, ACK/NACK signal) to base station 100 using the PUCCH resources specified in the UL grant.

[0161] For example, in the example shown in FIG. 8, base station (gNB) 100 detects preamble #1 of message A transmitted by UE #A (detection result: SUCCESS) and correctly decodes the PUSCH (decode result: SUCCESS). That is, the base station 100 configures, in the UL grant included in the RAR for UE #A in message B, PUCCH resources to transmit an ACK/NACK signal for message B. UE #A transmits an ACK/NACK signal for message B based on the PUCCH resources, specified in the UL grant included in the RAR for UE #A included in message B.

[0162] In addition, in the operation example 2 of the 2-way random access procedure according to Embodiment 1 (see, for example, FIG. 8), base station 100 also transmits message B when it detects the RACH preamble of message A, but it cannot properly decode part as data. Here, message B includes RAR. For example, with respect to the terminal 200 transmitting the corresponding RACH preamble, the RAR may contain retransmission request information for the data portion and information (UL Grant) of the resources used by the terminal 200 in the uplink.

[0163] In the present embodiment, for example, upon detecting the RACH preamble of message A (in FIG. 8 of message A of UE #B), but at the same time, if unable to correctly decode the data part, the base station 100 indicates to grant UL included in RAR, uplink resources (eg, PUSCH resources) to retransmit the data portion (eg, PUSCH) in message A. Terminal 200 (UE #B in FIG. 8) retransmits the data portion ( e.g., PUSCH) of message A based on the PUSCH resources specified in the UL grant included in the RAR for terminal 200 in message B.

[0164] It should be noted that the RAR may contain a flag to determine whether the UL grant indicates uplink resources for retransmission of message A (e.g., PUSCH) or PUCCH resources for ACK/NACK signaling for message B.

[0165] According to NR 15, for example, the UL grant included in RAR has a 27-bit field. In the present embodiment, for example, a portion of the 27-bit field included in the UL grant may be used to indicate PUCCH resources for ACK/NACK signaling for message B. The size of the field included in the UL grant is not limited to 27 bits.

[0166] In addition, for example, if the number of combinations of a plurality of parameters related to PUCCH resources included in a PUCCH resource set is 16 (according to NR 15), 4 bits may be used to indicate PUCCH resources for transmitting an ACK/NACK signal for message B. The remainder of the field may be used for other purposes or may be reserved. It should be noted that the number of bits used to indicate PUCCH resources is not limited to 4 bits.

[0167] According to the present embodiment, base station 100 indicates PUCCH resources for ACK/NACK signaling for message B with the UL grant included in the RAR in message B. In other words, base station 100 can configure (in other words, schedule) PUCCH resources for each terminal 200 in the UL grant included in the RAR for each terminal 200 in message B.

[0168] Thus, terminal 200 can separately determine, based on the UL grant configured for each terminal 200, PUCCH resources for transmitting an ACK/NACK signal for message B transmitted using multicast (in other words, a signal addressed to multiple terminals 200) . Thus, PUCCH resource collision between terminals 200 can be reduced when ACK/NACK signaling for message B (eg, RRC signal) is signaled.

[0169] In addition, since the base station 100 does not need to indicate PUCCH resources with the PDCCH (in other words, DCI), the resource consumption of the PDCCH can be reduced.

[0170] (Embodiment 3) Since the base station and the terminal according to the present embodiment have the same basic configurations as the base station 100 and the terminal 200 according to Embodiment 1, they will be described with reference to FIG. 4 and 5.

[0171] In the present embodiment, terminal 200 transmits an ACK/NACK signal for message B on an uplink data channel (eg, PUSCH).

[0172] Wherein, the base station 100 indicates to the terminal 200 the PUSCH resources for transmitting the ACK/NACK signal using, for example, granting the UL included in the RAR of the message B. The terminal 200 determines the PUSCH resources for transmitting the ACK/NACK signal for the message B (for example, RRC signal) based on, for example, the provision of a UL included in the RAR of message B addressed to terminal 200.

[0173] For example, in example 2 of operation of the 2-way random access procedure in Embodiment 1 (see, for example, FIG. 8), base station 100 transmits message B upon detecting and correctly decoding message A. Wherein, message B includes a message, including a RAR and a UE identifier for identifying the terminal 200.

[0174] In the present embodiment, upon detecting and correctly decoding message A, base station 100 indicates, in the UL grant included in RAR, uplink resources (e.g., PUSCH resources) to transmit an ACK/NACK signal for message B (e.g., RRC signal ). For example, if terminal 200 receives message B including information addressed to terminal 200, if the UE identifier included in message B matches the UE identifier transmitted in message A, and if message B includes a MAC PDU including signal RRC addressed to terminal 200, terminal 200 decodes the MAC PDU and transmits the result of the decoding (eg, an ACK/NACK signal) to the base station 100 using the PUSCH resources specified in the UL grant.

[0175] For example, in the example shown in FIG. 8, base station (gNB) 100 detects preamble #1 of message A transmitted by UE #A (detection result: SUCCESS) and correctly decodes the PUSCH (decode result: SUCCESS). Thus, the base station 100 configures, in the UL grant included in the RAR for UE #A in message B, PUSCH resources to transmit an ACK/NACK signal for message B. UE #A transmits an ACK/NACK signal for message B based on the PUSCH resources, specified in the UL grant included in the RAR for UE #A included in message B.

[0176] In addition, in the operation example 2 of the 2-way random access procedure according to Embodiment 1 (see, for example, FIG. 8), base station 100 also transmits message B when it detects the RACH preamble of message A, but it cannot properly decode part as data. Here, message B includes RAR. For example, with respect to the terminal 200 transmitting the corresponding RACH preamble, the RAR may contain retransmission request information for the data portion and information (UL Grant) of the resources used by the terminal 200 in the uplink.

[0177] In the present embodiment, for example, upon detecting the RACH preamble of message A (in FIG. 8 of message A of UE #B), but at the same time, if unable to correctly decode the data part, the base station 100 indicates to grant UL included in RAR, uplink resources (eg, PUSCH resources) to retransmit the data portion (eg, PUSCH) in message A. Terminal 200 (UE #B in FIG. 8) retransmits the data portion ( e.g., PUSCH) of message A based on the PUSCH resources specified in the UL grant included in the RAR addressed to terminal 200 in message B.

[0178] It should be noted that in the present embodiment, for example, in FIG. 6, processes for transmitting and receiving PUCCH resource information for transmitting ACK/NACK for message B (eg, processes ST101 and ST102) are optional.

[0179] In addition, for example, one of the following two methods can be applied as a matching method for matching the ACK/NACK signal to PUSCH.

[0180] The first method is a method in which, as in the case of the UL Shared Channel (UL-SCH), the ACK/NACK signal is mapped to the PUSCH in the same way as the data part is mapped. In this case, the ACK/NACK signal is transmitted according to the MCS specified in the UL grant.

[0181] The second method is a method of mapping an ACK/NACK signal to a PUSCH using a method of multiplexing uplink control information (UCI) in a PUSCH (see, for example, NFL 2 and 3), for example, in the absence of UL -SCH (according to edition 15 NR). In this case, the ACK/NACK signal may be transmitted according to an MCS lower than the MCS specified in the UL grant.

[0182] According to the present embodiment, base station 100 indicates PUSCH resources for ACK/NACK signaling for message B with the UL grant included in the RAR in message B. In other words, base station 100 can configure (in other words, schedule) PUSCH resources for each terminal 200 in the UL grant included in the RAR for each terminal 200 in message B.

[0183] In this way, the terminal 200 can separately determine, based on the UL grant configured for each terminal 200, PUSCH resources for transmitting an ACK/NACK signal for message B (in other words, a signal addressed to a plurality of terminals 200) transmitted using multicast. . Thus, PUSCH resource collision between terminals 200 can be reduced when ACK/NACK signaling for message B (eg, RRC signal) is signaled.

[0184] In addition, since the base station 100 does not need to indicate PUSCH resources with the PDCCH (in other words, DCI), the resource consumption of the PDCCH can be reduced.

[0185] In addition, in the present embodiment, PUSCH resources for retransmitting message A (e.g., PUSCH) or PUSCH resources for signaling ACK/NACK for message B are specified in the UL grant included in the RAR of message B. In other words, in the present embodiment, the resources indicated in the RAR of the message B are PUSCH resources regardless of the result of detection and decoding of the message A by the base station 100. Thus, according to the present embodiment, the information indicated in the UL grant in the RAR does not need to change depending on the result of decoding message A by the base station 100. Thus, the RAR configuration can be simplified.

[0186] Exemplary embodiments of the present invention have been described above.

[0187] The above embodiments have been described with respect to the case where terminal 200 transmits an ACK/NACK signal (ACK or NACK) for message B. However, terminal 200 may, for example, send NACK to base station 100 when it fails to decode message B, and shall not send an ACK to base station 100 upon successful decoding of message B.

[0188] For example, if the PDCCH scheduled for message B is correctly decoded and the MAC PDU included in message B is correctly decoded, terminal 200 determines that the random access operation was successful. In addition, the terminal 200 does not send an ACK to the base station 100.

[0189] On the other hand, if the PDCCH for which message B is scheduled is correctly decoded, but if the MAC PDU included in message B cannot be correctly decoded, terminal 200 sends a NACK to base station 100 to request retransmission of message B.

[0190] Terminal 200 may control a timer when timing NACK transmission. Upon successful reception of the NACK transmitted by the terminal 200, the base station 100 retransmits the B message. B. Here, if the timer synchronizing NACK transmission exceeds the predetermined period, the terminal 200 performs the RACH operation again.

[0191] As described above, terminal 200 does not transmit ACK.

Thus, the uplink resource consumption can be reduced to reduce the power consumption of the terminal 200.

[0192] In addition, in the embodiments described above, terminal 200 may, for example, send an ACK to base station 100 when message B is successfully decoded, and does not need to send NACK to base station 100 when message B is unsuccessfully decoded.

[0193] For example, if message B includes a MAC PDU including RAR and a MAC PDU including a message (eg, MAC CE for conflict resolution) including identification information (eg, UE ID) for identifying terminal, and if terminal 200 fails to decode the B message, terminal 200 cannot determine whether the B message that terminal 200 attempted to decode is addressed to the corresponding terminal 200. For this reason, terminal 200 need not send a NACK to base station 100.

[0194] The present invention may be implemented using software, hardware, or software and hardware. Each functional block used in the description of each embodiment above may be partially or wholly implemented by an LSI such as an integrated circuit, and each process described in each embodiment may be partially or wholly controlled by the same LSI or combinations of LSI. The LSI may be formed separately as chips, or a single chip may be formed to include some or all of the functional blocks. The LSI may include input and output data associated with it. The LSI in this document may be referred to as an integrated circuit (IC), system LSI, super-LSI or ultra-LSI depending on the difference in the degree of integration. However, the implementation method of the integrated circuit is not limited to the LSI, and may be implemented using a dedicated circuit, a general purpose processor, or a special purpose processor. In addition, an FPGA (Field Programmable Gate Array) can be used, which can be programmed after the LSI is manufactured or reconfigurable processor, in which the connection configuration and settings of the circuit cells located inside the LSI can be changed. The present invention may be implemented as digital data processing or analog data processing. If future integrated circuit technology replaces LSIs as a result of the development of semiconductor technology or other derivative technology, functional blocks can be integrated using future integrated circuit technology. In addition, biotechnology may be applied.

[0195] The present invention may be implemented using any type of apparatus, device, or system having a communication function, referred to as communication apparatuses. The communications apparatus may include a transceiver and a processing/control circuit. The transceiver may comprise a receiver and a transmitter and/or function as both a receiver and a transmitter. A transceiver in the form of a transmitter and receiver may include a radio frequency (RF) module and one or more antennas. The RF module may include an amplifier, an RF modulator/demodulator, and the like. Non-limiting examples of such communication devices include telephone (e.g., cellular phone, smartphone), tablet, personal computer (PC) (e.g., laptop, desktop computer, netbook), camera (e.g., digital camera/camcorder), digital player (digital audio/video player), wearable device (e.g. wearable camera, smart watch, tracking device), game console, digital e-book reader, healthcare/medical teleservices (remote healthcare and medicine) and a vehicle that has communication functionality (for example, a car, an aircraft, a ship), as well as various combinations thereof.

[0196] The communication apparatus is not limited to portable or mobile devices, and may also include any type of apparatus, device, or system that is non-portable or stationary, such as a smart home device (e.g., electrical appliance, lighting device, smart meter, control panel) , vending machine and any other “things” in the Internet of Things (IoT) network.

[0197] Communication may include the exchange of data, for example, through a cellular system, wireless LAN system, satellite system, etc., as well as various combinations thereof.

[0198] The communication apparatus may include a device, such as a controller or a sensor, that is connected to a communication device that performs the communication function described in the present invention. For example, the communication device may include a controller or sensor that generates control signals or data signals used by the communication device to perform the communications function of the communication device.

[0199] A communications apparatus may also include an infrastructure entity such as a base station, an access point, and any other apparatus, device, or system configured to communicate with or control apparatuses, such as apparatuses described in the examples above that do not have restrictive nature.

[0200] A terminal according to one embodiment of the present invention includes: a control circuit that, during operation, determines, based on a parameter configured for each of the plurality of terminals, a resource used for transmitting a response signal for a downlink signal addressed to a specified many terminals; and a transmission circuit that, during operation, transmits a response signal at the specified resource.

[0201] In an exemplary embodiment of the present invention, the control circuit determines the resource based on the value indicated in the control information for the downlink signal, the resource for which the control information is allocated, and the parameter.

[0202] In an exemplary embodiment of the present invention, the downlink signal includes response information to the random access signal transmitted by each of the plurality of terminals, and a parameter is included in said response information.

[0203] In an exemplary embodiment of the present invention, the downlink signal includes information about a response to a random access signal transmitted by each of the plurality of terminals, and the parameter indicates a value associated with information included in the random access signal, said information is for identifying each of the plurality of terminals.

[0204] In one embodiment of the present invention, the downlink signal includes information about the response to the random access signal transmitted by each of the plurality of terminals, and the parameter indicates a value related to the order of the response information corresponding to each of the plurality of terminals, in downlink signal.

[0205] In an exemplary embodiment of the present invention, the downlink signal includes information about the response to the random access signal transmitted by each of the plurality of terminals, and the parameter indicates a value associated with the preamble number used in the random access signal.

[0206] In an exemplary embodiment of the present invention, the downlink signal includes response information to a random access signal transmitted by each of the plurality of terminals, the random access signal having a preamble part and a data part, and the parameter indicates value associated with the port number of the reference signal used for the data part.

[0207] In the exemplary embodiment of the present invention, the downlink signal includes response information to the random access signal transmitted by each of the plurality of terminals, and the parameter is uplink resource allocation information included in said response information .

[0208] In an exemplary embodiment of the present invention, the resource is an uplink control resource.

[0209] In an exemplary embodiment of the present invention, the resource is an uplink data resource.

[0210] The transmission method according to an exemplary embodiment of the present invention includes: determining, based on a parameter configured for each of the plurality of terminals, a resource used to transmit a response signal for a downlink signal addressed to the plurality of terminals; and transmitting a response signal in the indicated resource.

[0211] The description of Japanese Patent Application No. 2019-061499 dated March 27, 2019, including the technical description, drawings, and abstract, is incorporated herein by reference in its entirety.

Industrial Applicability

[0212] An exemplary embodiment of the present invention can be applied to mobile communication systems.

List of reference positions

[0213]

100 - base station

101, 209 - controller

102 - data generator

103, 107, 110, 212, 214 - encoder

104 - retransmission controller

105, 108, 111, 213, 215 - modulator

106 - senior control signal generator

109 - downlink control signal generator

112, 216 - signal distribution device

113, 217 - IFFT section

114, 218 - transmitter

115, 201 - antenna

116, 202 - receiver

117, 203 - FFT section

118, 204 - extractor 119 - detector

120, 205 - demodulator

121, 206, 208 - decoder 200 - terminal

207 - downlink control signal demodulator

210 - PRACH preamble generator

211 - ACK/NACK generator

Claims (38)

1. Communication terminal, containing: a control scheme that, during operation, determines, based on a first parameter included in the B message, which is a response to the transmission of the random access signal, a resource used to send a response to the message B; and a transmission scheme that, during operation, transmits a response signal at the specified resource. 2. The communication terminal of claim 1, wherein the control circuit determines the resource based on the first parameter without using Physical Downlink Control Channel (PDCCH) bits and control channel element (CCE) index. 3. The communication terminal of claim 1, wherein the control circuit determines the resource based on a first parameter of the plurality of resources, the plurality of resources being indicated by higher layer signaling. 4. The communications terminal of claim 1, wherein message B also includes transmission timing information used to transmit the response signal. 5. The communication terminal according to claim 1, wherein the control circuit considers the random access procedure successful in the case where the identification information on the communication terminal is included in message B. 6. The communication terminal according to claim 1, wherein the transmission circuit performs transmission of message 3 by using another resource indicated by message B in case message B requests retransmission of the random access signal data portion. 7. The communication terminal according to claim 6, in which the identification information at the communication terminal is not included in the message B in the case where the message B requests retransmission of a portion as random access signal data. 8. The communication terminal according to claim 1, wherein the control circuit launches a window related to message B after transmission of the random access signal, and the transmission circuit performs retransmission of the random access signal in case message B is not received in the window. 9. The communication terminal according to claim 1, wherein the message B does not include control information of one or more communication terminals, the random access signal preamble part of which is not detected in the base station. 10. The communication terminal of claim 1, wherein the random access signal includes both a random access channel (RACH) preamble and a physical uplink shared channel (PUSCH). 11. The base station, comprising: a control circuit that, during operation, determines the resource used to transmit a response signal to message B, which is a response to the transmission of a random access signal; and a transmission scheme that, during operation, transmits to the communication terminal a first parameter indicating a resource by using a B message. 12. The base station of claim 11, wherein the resource is indicated by the first parameter without using the Physical Downlink Control Channel (PDCCH) bits and the control channel element (CCE) index. 13. The base station of claim 11, wherein the control circuit determines a resource from a plurality of resources, the plurality of resources being indicated by higher layer signaling. 14. The base station of claim 11, wherein message B also includes transmission timing information used to transmit the response signal. 15. The base station of claim 11, wherein message B includes identification information at the communication terminal that indicates that the random access procedure was successful at the communication terminal. 16. The base station of claim 11, wherein message B includes a request to retransmit a portion in the form of random access signal data and uplink resource information, and also comprising: a receiving scheme that, during operation, receives message 3 on another resource indicated by the uplink resource information. 17. The base station of claim 16, wherein the identification information at the communication terminal is not included in message B in the case where message B requests retransmission of the random access signal data part. 18. The base station of claim 11, further comprising a reception circuit that, during operation, receives a retransmission of the random access signal in the event that message B is not transmitted in the window related to message B. 19. The base station of claim 11, wherein the message B does not include control information of one or more communication terminals, the random access signal preamble portion of which is not detected in the base station. 20. The base station of claim 11, wherein the random access signal includes both a random access channel (RACH) preamble and a physical uplink shared channel (PUSCH). 21. A communication method performed by a communication terminal, including: determining, based on a first parameter included in message B, which is a response to the transmission of the random access signal, a resource used to send a response signal to the message B; and transmitting a response signal in the specified resource. 22. The communication method performed by the base station, including: determining a resource used for transmitting a response signal to the message B, which is a response to the transmission of the random access signal; and transmission to the communication terminal of the first parameter indicating the resource in message B. 23. Integrated circuit for communication, implemented in the communication terminal, containing: a control circuit that, during operation, controls the determination of a resource used for signaling a response to message B based on a first parameter included in message B, which is a response to transmission of a random access signal; and a transmission scheme that, during operation, controls the transmission of a response signal in the specified resource. 24. Integrated circuit for communication, implemented in the base station, containing: a control circuit that, during operation, manages the determination of a resource used for signaling a response to message B, which is a response to the transmission of a random access signal; and a transfer scheme that, during operation, controls the transfer of the first parameter indicating the resource in message B.

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