Communication device, communication method and integrated circuit

Abstract

To provide a communication apparatus capable of properly performing random access processing.SOLUTION: A communication apparatus includes: a control circuit that is configured so as to, when the path loss between a communication apparatus and a base station is less than a threshold, select a random access preamble from first multiple random access preambles, and when the path loss is more than or equal to the threshold between the communication apparatus and the base station, select a random access preamble from second multiple random access preambles; and a transmitter that transmits the selected random access preamble. The first multiple interlace numbers associated with the first multiple random access preambles are consecutive, the second multiple interlace numbers associated with the second multiple random access preambles are consecutive, and the first multiple interlace numbers are different from the second multiple interlace numbers.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a transmitting device, a receiving device, a transmitting method, and a receiving method. [Background technology]

[0002] In the 5G standardization, new radio access technology (NR) that is not necessarily backward compatible with LTE / LTE-Advanced is being discussed at 3GPP.

[0003] In NR, operation in unlicensed bands is being discussed, similar to LTE-LAA (License-Assisted Access). LTE-LAA supports operation in unlicensed bands that is incidental to operation in licensed bands. On the other hand, in NR, there is a demand for operation in unlicensed bands (stand-alone operation) without using licensed bands.

[0004] Therefore, in NR, the introduction of PRACH (Physical Random Access Channel), which is used by terminals (also called UE (User Equipment)) for initial connection with base stations (also called gNB), into unlicensed bands is being considered (see, for example, Non-Patent Document 1). [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] R2-1809940, LG Electronics Inc., “Considerations on 2-Step CBRA procedure for NR-U SA”, 3GPP TSG-RAN WG2 Meeting#AH-1807 [Non-patent document 2] R1-1809726, Ericsson, “Feature lead summary for UL Signals and Channels”, 3GPP TSG-RAN WG1 Meeting#94 Summary of the Invention

[0006] However, the random access method in NR has not been thoroughly studied.

[0007] Non-limiting examples of the present disclosure contribute to providing a transmitting device, a receiving device, a transmitting method, and a receiving method that can appropriately perform random access processing.

[0008] A transmitting device according to one embodiment of the present disclosure includes a transmitting circuit that transmits a data signal, and a control circuit that determines a second resource to be used for transmitting the data signal based on a first resource to be used for transmitting a preamble signal.

[0009] A receiving device according to one embodiment of the present disclosure includes a receiving circuit that receives a data signal, and a control circuit that determines resources to be used for transmitting the data signal based on resources to be used for transmitting a preamble signal.

[0010] A transmission method according to an embodiment of the present disclosure determines resources to be used for transmitting a data signal based on resources to be used for transmitting a preamble signal, and transmits the data signal.

[0011] A receiving method according to an embodiment of the present disclosure determines resources to be used for transmitting a data signal based on resources to be used for transmitting a preamble signal, and receives the data signal.

[0012] These comprehensive or specific aspects may be realized as a system, an apparatus, 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.

[0013] According to an embodiment of the present disclosure, random access processing can be performed appropriately.

[0014] Further advantages and benefits of certain aspects of the present disclosure will become apparent from the specification and drawings. Such advantages and / or benefits may be provided by some of the embodiments and features described in the specification and drawings, respectively, but not necessarily all of them may be provided to obtain one or more identical features. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 shows an example of a random access procedure. [Figure 2] An example of block-based interlace design [Figure 3] FIG. 1 is a block diagram showing a partial configuration of a terminal according to a first embodiment; [Figure 4] FIG. 1 is a block diagram showing a partial configuration of a base station according to a first embodiment; [Figure 5] Block diagram showing the configuration of a terminal according to the first embodiment. [Figure 6] Block diagram showing a configuration of a base station according to a first embodiment. [Figure 7] FIG. 1 is a sequence diagram showing an example of the operation of a terminal and a base station according to the first embodiment; [Figure 8] FIG. 10 is a diagram showing an example of a correspondence relationship between transmission resources of a preamble part and a data part according to a first derivation example of the first embodiment; [Figure 9] FIG. 1 shows an example of transmission resource allocation according to Derivation Example 1 of Embodiment 1. [Figure 10] FIG. 10 is a diagram showing another example of the correspondence relationship between transmission resources of a preamble part and a data part according to derivation example 1 of the first embodiment; [Figure 11] FIG. 10 is a diagram showing an example of a correspondence relationship between transmission resources of a preamble part and a data part according to a second derivation example of the first embodiment; [Figure 12]FIG. 10 is a diagram showing an example of transmission resource allocation according to a second derivation example of the first embodiment. [Figure 13] FIG. 10 is a diagram showing an example of a correspondence relationship between transmission resources of a preamble part and a data part according to a third derivation example of the first embodiment; [Figure 14] FIG. 10 is a diagram showing an example of transmission resource allocation according to a third derivation example of the first embodiment. [Figure 15] FIG. 10 is a diagram showing an example of a correspondence relationship between transmission resources of a preamble part and a data part according to a derivation example 4 of the first embodiment; [Figure 16] FIG. 10 is a diagram showing an example of transmission resource allocation according to a derivation example 4 of the first embodiment. [Figure 17] FIG. 10 is a diagram showing an example of a correspondence relationship between transmission resources of a preamble part and a data part according to a derivation example 5 of the first embodiment; [Figure 18] FIG. 10 is a diagram showing an example of transmission resource allocation according to a derivation example 5 of the first embodiment. [Figure 19] FIG. 10 is a diagram showing an example of a correspondence relationship between transmission resources of a preamble part and a data part according to a sixth derivation example of the first embodiment; [Figure 20] FIG. 10 is a diagram showing an example of transmission resource allocation according to a derivation example 6 of the first embodiment. [Figure 21] FIG. 13 is a diagram showing an example of a correspondence relationship between transmission resources of a preamble part and a data part according to a seventh derivation example of the first embodiment; [Figure 22] FIG. 10 is a diagram showing an example of transmission resource allocation according to a seventh derivation example of the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0017] [Random Access Procedure] For example, the random access procedure in the licensed band is implemented using four-step random access (also called 4-step Random Access Channel (RACH) or 4-Step Contention Based Random Access (CBRA)).

[0018] In four-stage random access, for example, as shown in FIG. 1(a), a terminal (UE) transmits a preamble to a base station (gNB) as a first-stage transmission (MSG1). After receiving and decoding MSG1, the base station notifies the terminal of a response to the preamble (RA response) and scheduling information including the uplink transmission timing of MSG3 as a second-stage transmission (MSG2). After receiving and decoding MSG2, the terminal notifies the base station of RRC connection request information such as information about the terminal (e.g., terminal ID) using the scheduling information indicated in MSG2 as a third-stage transmission (MSG3). Finally, the base station notifies the terminal of control information for the terminal to establish an RRC connection or control information for contention resolution as a fourth-stage transmission (MSG4). The control information for contention resolution is, for example, a control signal notified from the terminal. In contention resolution, for example, a terminal compares the control signal transmitted by the terminal with the control information for contention resolution included in MSG4, and if they are not identical, it starts again from MSG1 to avoid RACH collisions between multiple terminals.

[0019] On the other hand, the introduction of two-step random access (also called 2-step RACH or 2-Step CBRA) is being considered as a random access procedure in the unlicensed band of NR (see, for example, Non-Patent Document 1).

[0020] In two-stage random access, for example, as shown in FIG. 1(b), the terminal transmits a preamble part (corresponding to the preamble (or MSG1) in FIG. 1(a)) and a data part (corresponding to MSG3 in FIG. 1(a)) to the base station as the first stage transmission (MSG1). The terminal may transmit the preamble part and the data part simultaneously, at consecutive times, or within a specified time (for example, within one slot).

[0021] Next, as shown in Figure 1(b), after receiving and decoding MSG1, the base station notifies the terminal of the uplink transmission timing and control information for the terminal's RRC connection or control information for contention resolution (corresponding to MSG2 and MSG4 in Figure 1(a)) as the second stage of transmission (MSG2).

[0022] The introduction of two-stage random access in unlicensed NR bands is expected to reduce the number of LBT (Listen Before Talk) processes and reduce the latency of random access. However, the introduction of two-stage random access is not limited to unlicensed bands. For example, it is being considered to reduce the latency of data transmission and reception by applying two-stage random access to licensed bands and applying it to services for Ultra-Reliable and Low Latency Communications (URLLC).

[0023] [PRACH] For example, a PRACH (e.g., MSG1 in FIG. 1(a)) for four-stage random access used in an NR licensed band is composed of a cyclic prefix (CP), a preamble, and a guard period (GP). The preamble is generated, for example, from a code sequence with good correlation characteristics (e.g., a Cyclic Shifted Zadoff-Chu (CS-ZC) sequence). The CP is a signal that is a copy of a portion of the preamble. The GP is a non-transmission interval. Note that the preamble is not limited to a CS-ZC sequence, and may be any code sequence with good correlation characteristics.

[0024] These pieces of information related to the PRACH are reported to the terminal as, for example, cell information of the base station. For example, a different CS-ZC sequence is uniquely associated with each preamble number. The terminal transmits a CS-ZC sequence corresponding to a randomly selected preamble number as a preamble. For example, even when multiple terminals transmit PRACH using the same time and frequency resources, if the multiple terminals each select different preamble numbers, the base station can simultaneously detect multiple preamble numbers (in other words, preambles of multiple terminals) by detecting correlation between the CS-ZC sequences.

[0025] [B-IFDMA] As one of the frequency resource allocation methods for PRACH (e.g., MSG1 in FIG. 1(a)), which is a channel for four-stage random access in unlicensed bands, application of block-based interlace design (also called B-IFDMA (Block-interleaved Frequency Division Multiple Access)) is being considered (see, for example, Non-Patent Document 2).

[0026] FIG. 2 shows an example of a block-based interlace design.

[0027] Block-based interlace design is used as a frequency resource allocation method for the Physical Uplink Shared Channel (PUSCH) in LTE-LAA. B-IFDMA is a signal transmission method that uses bands called interlaces that are uniformly distributed in the frequency direction within the system band to comply with the Occupied Channel Bandwidth (OCB) restrictions of unlicensed bands and mitigate the impact of the Power Spectral Density (PSD) limit.

[0028] An interlace is composed of a group of consecutive subcarriers (a group of consecutive frequency resources, for example, one PRB (Physical Resource Block)). For example, multiple interlaces are included in a band (hereinafter referred to as a cluster or cluster block) obtained by dividing a system band or a partial band of the system band (for example, a BWP (Bandwidth Part)) into multiple blocks. A number (hereinafter referred to as an "interlace number") is assigned to the interlaces included in each cluster.

[0029] Note that a cluster has the same meaning as the "interval" between interlaces with the same interlace number. In other words, interlaces with the same interlace number are uniformly distributed in the frequency direction across multiple Cluster Blocks.

[0030] Furthermore, a cluster is not limited to a band obtained by dividing the system band into multiple blocks, but may also be defined as a band obtained by dividing a certain band (for example, a band in which LBT (listen before talk) is implemented, a 20 MHz band, or a band that is an integer multiple of 20 MHz) into multiple blocks.

[0031] For example, in the example of Figure 2, the five interlaces in a cluster into which a certain band is divided are assigned interlace numbers as interlace #0, #1, #2, #3, #4. Also in Figure 2, each cluster is assigned a cluster number as Cluster #0, #1, #2, #3, ...

[0032] For example, a case will be described in which one interlace number (interlace #0 in FIG. 2) is set in the transmission resource of the PRACH as shown in FIG. 2. For example, when terminal A (UE #A) and terminal B (UE #B) each select different preamble numbers (for example, different CS-ZC sequences (ZC #X and ZC #Y)), the preambles transmitted from terminal A and terminal B are code-multiplexed.

[0033] However, in the unlicensed band of NR, radio resource allocation for two-stage random access has not been fully discussed. In particular, radio resource allocation for the data part of MSG1 (e.g., see Figure 1(b)) when block-based interlace design (e.g., see Figure 2) is applied to the preamble part of MSG1 (e.g., see Figure 1(b)) has not been discussed.

[0034] As described above, when block-based interlace design is applied to the radio resource allocation method for the preamble part in two-stage random access, different code sequences (e.g., CS-ZC sequences) are used for preambles of multiple terminals, each generated from a different preamble number. This allows preambles of multiple terminals to be code-multiplexed in frequency resources with the same interlace number.

[0035] On the other hand, in two-stage random access, the data part contains several tens of bits of transmission information such as a terminal-specific ID, and therefore the amount of information in the data part is larger than that in the preamble part. For this reason, it is difficult to apply code multiplexing to the data part in the same way as to the preamble part.

[0036] For example, if a different CS-ZC sequence is uniquely associated with each transmission information pattern of a Data part, the number of CS-ZC sequences associated with the transmission information patterns may exceed the number of sequences that can be generated. This also poses problems such as an increase in the processing load for correlation detection at the base station or degradation of detection performance.

[0037] Therefore, a method for appropriately allocating radio resources for the Data part when a terminal transmits a PRACH in two-stage random access will be described below.

[0038] In the following description, "two-step random access" refers to a random access procedure in which a preamble part (corresponding to MSG1 in four-step random access) and a data part (corresponding to MSG3 in four-step random access) are transmitted simultaneously, on consecutive radio resources, or on radio resources within a predetermined time period (e.g., within a slot). In other words, two-step random access refers to a random access procedure in which a data part is transmitted together with a preamble part. Alternatively, two-step random access refers to a random access procedure in which a terminal transmits a data part before receiving a response to a preamble (corresponding to MSG2 in four-step random access), or transmits a data part without waiting for a response to a preamble.

[0039] (Embodiment 1) [Communication System Overview] A communication system according to an embodiment of the present disclosure includes a terminal 100 and a base station 200. In the following description, as an example, the terminal 100 (corresponding to a transmitting device) transmits a PRACH, and the base station 200 (corresponding to a receiving device) receives the PRACH.

[0040] 3 is a block diagram showing a partial configuration of a terminal 100 according to an embodiment of the present disclosure. In the terminal 100 shown in FIG. 3, a radio transmitting unit 108 transmits a data signal (e.g., a data part). A control unit 101 determines a second resource to be used for transmitting the data signal based on a first resource (e.g., a code sequence corresponding to a preamble number) to be used for transmitting a preamble signal (e.g., a preamble part).

[0041] 4 is a block diagram showing a partial configuration of base station 200 according to an embodiment of the present disclosure. In base station 200 shown in FIG. 4, radio receiving unit 202 receives a data signal (e.g., a data part). Control unit 203 determines resources to be used for transmitting the data signal based on resources (e.g., a code sequence corresponding to a preamble number) used for transmitting a preamble signal (e.g., a preamble part).

[0042] [Device configuration] FIG. 5 is a block diagram showing the configuration of terminal 100 according to this embodiment.

[0043] In FIG. 5, terminal 100 includes control unit 101, preamble generation unit 104, preamble resource allocation unit 105, data generation unit 106, data resource allocation unit 107, radio transmission unit 108, antenna 109, radio reception unit 110, and demodulation and decoding unit 111.

[0044] The control unit 101 determines, for example, radio resources to which the PRACH is allocated (for example, resources to be allocated to the preamble part and data part included in MSG1 in two-stage random access). For example, the control unit 101 includes a preamble resource setting unit 102 and a data resource setting unit 103.

[0045] The preamble resource setting unit 102 determines candidates for transmission resources to be allocated to the preamble part, for example, based on PRACH transmission resource information (also referred to as random access configuration) indicating transmission resources for PRACH available in the cell of the base station 200. The transmission resources for the preamble include, for example, frequency resources indicating a frequency band represented by an interlace number and a cluster number, or time resources such as transmission timing. Furthermore, the candidates for transmission resources to be allocated to the preamble part are uniquely associated with, for example, a preamble number.

[0046] The preamble resource setting unit 102 randomly selects one preamble number from a group of preamble numbers including at least one preamble number, and outputs information indicating the selected preamble number and the transmission resource associated with the preamble number to the data resource setting unit 103, the preamble generation unit 104, and the preamble resource allocation unit 105.

[0047] The PRACH transmission resource information available to terminal 100 includes, for example, configuration information related to PRACH, such as a sequence number for a preamble, a CS amount, a PRACH time resource (for example, a period), a PRACH frequency resource position, and a preamble format number. The PRACH transmission resource information is included in control information broadcast from connected base station 200 (for example, a serving cell), and is notified in advance to terminal 100. Some of the PRACH transmission resource information may be, for example, system-wide information defined in specifications, and may not be notified from base station 200 to terminal 100.

[0048] The data resource setting unit 103 determines the transmission resource for the data part based on the transmission resource of the preamble part input from the preamble resource setting unit 102. For example, the data resource setting unit 103 sets the transmission resource for the data part based on the preamble number input from the preamble resource setting unit 102. The transmission resource for the data part includes, for example, a frequency resource represented by an interlace number and a cluster number, or a time resource such as transmission timing. The data resource setting unit 103 outputs information indicating the set transmission resource to the data resource allocating unit 107. Note that the method of deriving the transmission resource for the data part in the data resource setting unit 103 will be described in detail later.

[0049] Preamble generation section 104 generates a CS-ZC sequence using information indicating the transmission resource inputted from preamble resource setting section 102 (for example, a sequence number and cyclic shift amount corresponding to the selected preamble number), and outputs the generated CS-ZC sequence as a preamble part signal (or preamble signal) to preamble resource allocation section 105. Here, if different preamble numbers are selected in preamble resource setting section 102, different code sequences (CS-ZC sequences, etc.) that are orthogonal or have little correlation are generated in preamble generation section 104.

[0050] Preamble resource allocation section 105 allocates the preamble part signals inputted from preamble generation section 104 to the transmission resource information (for example, frequency resources corresponding to cluster numbers and interlace numbers) inputted from preamble resource setting section 102. Furthermore, preamble resource allocation section 105 outputs the preamble part signals to radio transmission section 108 based on the transmission timing indicated in the transmission resource information inputted from preamble resource setting section 102.

[0051] The data generation unit 106 generates a data signal (e.g., corresponding to MSG3 in four-stage random access) including RRC connection request information such as a terminal ID. The data generation unit 106 encodes and modulates the generated data signal, and outputs the modulated signal (data series) to the data resource allocation unit 107 as a data part signal.

[0052] The data resource allocation unit 107 allocates the data part signals received as input from the data generation unit 106 to frequency resources corresponding to the cluster numbers and interlace numbers indicated in the transmission resource information received as input from the data resource configuration unit 103. The data resource allocation unit 107 also outputs the data part signals to the radio transmission unit 108 based on the transmission timing indicated in the transmission resource information received as input from the data resource configuration unit 103.

[0053] The radio transmitting unit 108 performs transmission processing such as D / A conversion and up-conversion on the preamble part signal input from the preamble resource allocating unit 105 and the data part signal input from the data resource allocating unit 107, and transmits the radio signal obtained by the transmission processing (e.g., corresponding to MSG1 (see FIG. 1(b)) in two-stage random access) from the antenna 109 to the base station 200.

[0054] The radio receiving unit 110 performs receiving processing such as down-conversion and A / D conversion on a received signal received from the base station 200 via the antenna 109, and outputs the received signal obtained by the receiving processing to the demodulation and decoding unit 111. The received signal received from the base station 200 includes, for example, a response data signal of the PRACH in two-stage random access (for example, MSG2 shown in FIG. 1(b)).

[0055] The demodulation and decoding unit 111 demodulates and decodes the received signal input from the radio receiving unit 110. If the demodulation and decoding unit 111 can correctly receive the response data signal of the PRACH, the RRC connection process by two-stage random access is completed.

[0056] [Base station configuration] FIG. 6 is a block diagram showing a configuration of base station 200 according to this embodiment.

[0057] In FIG. 6 , base station 200 includes antenna 201, radio receiving unit 202, control unit 203, preamble detection unit 206, demodulation and decoding unit 207, scheduling unit 208, data generation unit 209, coding and modulation unit 210, and radio transmission unit 211.

[0058] The radio receiving unit 202 performs receiving processing such as down-conversion and A / D conversion on a RACH signal (e.g., MSG1 in two-stage random access) from the terminal 100 received via the antenna 201, for example, in a PRACH transmission resource available in the cell of the base station 200, and outputs the signal obtained by the receiving processing to the preamble detecting unit 206 and the demodulating and decoding unit 207.

[0059] Control section 203 determines, for example, radio resources to which each terminal 100 allocates a PRACH (for example, allocation resources for a preamble part and a data part included in MSG1 in two-stage random access). Note that the method of configuring the PRACH transmission resource in control section 203 is the same as the method of configuring the PRACH transmission resource in terminal 100 (control section 101). For example, control section 203 includes preamble resource configuration section 204 and data resource configuration section 205.

[0060] The preamble resource setting unit 204 outputs, for example, preamble numbers available in the cell of the base station 200 to the data resource setting unit 205 and the preamble detection unit 206 .

[0061] The data resource setting unit 205 sets the transmission resource of the data part based on the preamble number received from the preamble resource setting unit 204. The data resource setting unit 205 outputs information indicating the set transmission resource to the demodulation and decoding unit 207. A method for deriving the transmission resource of the data part in the data resource setting unit 205 will be described later in detail.

[0062] The preamble detection unit 206 generates a replica signal for detecting a PRACH preamble (for example, a CS-ZC sequence) using the sequence number and CS number corresponding to the preamble number received from the preamble resource configuration unit 204. The preamble detection unit 206 performs a correlation process between the generated replica signal and the signal received from the radio reception unit 202, and detects and estimates the timing of the PRACH preamble. The preamble detection unit 206 outputs the detection result and estimation result to the scheduling unit 208.

[0063] The correlation processing in preamble detection unit 206 may be a process of calculating a delay profile used in timing estimation by performing correlation processing in the time domain, or a process of calculating a delay profile by performing correlation processing (division processing) in the frequency domain and then performing IFFT (Inverse Fast Fourier Transform).

[0064] The demodulation and decoding unit 207 performs demodulation and decoding processing on received data (Data part signal) included in the transmission resource indicated in the transmission resource information input from the Data resource setting unit 205, out of the received signals input from the radio receiving unit 202, and outputs the decoding result to the scheduling unit 208.

[0065] Scheduling section 208 sets up an RRC connection with terminal 100 based on the timing information of terminal 100 input from preamble detection section 206 or terminal ID information etc. included in the Data part signal input from demodulation and decoding section 207. Scheduling section 208 sets data transmission resources including control information for the RRC connection on the terminal 100 side or control information for Contention resolution, and outputs the data transmission resource information to data generation section 209.

[0066] In the base station 200, for example, the control unit 203, the preamble detection unit 206, and the demodulation / decoding unit 207 attempt to detect the preamble part and demodulate and decode the data part signal for each preamble number available in the cell of the base station 200. Meanwhile, the scheduling unit 208 performs RRC connection processing for terminals 100 for which the decoding result of the data part signal is OK (no error).

[0067] The data generation unit 209 generates data including control information for RRC connection on the terminal side or control information for contention resolution using the radio resources indicated in the data transmission resource information input from the scheduling unit 208, and outputs the generated data signal (e.g., equivalent to MSG2 for two-stage random access) to the coding and modulation unit 210.

[0068] The encoding / modulation unit 210 modulates and encodes the data signal input from the data generation unit 209 and outputs the modulated signal to the radio transmission unit 211 .

[0069] The radio transmitting unit 211 performs transmission processing such as D / A conversion, up-conversion, and amplification on the signal input from the encoding / modulating unit 210, and transmits the radio signal obtained by the transmission processing (for example, MSG2 in two-stage random access (see, for example, Figure 1(b))) from the antenna 201 to the terminal 100.

[0070] [Operations of Terminal 100 and Base Station 200] An example of the operation of terminal 100 and base station 200 having the above configuration will be described.

[0071] FIG. 7 is a sequence diagram showing an example of the operation of the terminal 100 (FIG. 5) and the base station 200 (FIG. 6).

[0072] In FIG. 7, base station 200 notifies (in other words, broadcasts) cell information including information on PRACH transmission resources available in the cell to terminal 100 (ST101).

[0073] Terminal 100 determines the transmission resource for a preamble part signal included in a PRACH transmitted by terminal 100, based on PRACH transmission resource information indicated in the cell information (ST102).

[0074] Terminal 100 determines the transmission resource for the Data part signal based on the determined transmission resource for the Preamble part signal (ST103).

[0075] Terminal 100 uses the determined transmission resource to transmit a PRACH signal (for example, MSG1 in two-stage random access) including a preamble part signal and a data part signal to base station 200 (ST104).

[0076] Base station 200 detects the Preamble part signal and decodes the Data part signal (ST105). If the decoding of the Data part signal is OK, base station 200 sets up an RRC connection between corresponding terminal 100 and base station 200, and determines (schedules) a transmission resource for a response signal (for example, MSG2 in two-stage random access) that includes control information for the RRC connection on the terminal side or control information for contention resolution (ST106). Base station 200 transmits a data signal that includes the response signal to terminal 100 (ST107).

[0077] Terminal 100 decodes the data signal, and if it can decode the data signal without error and does not detect a collision with the RACH of another terminal, it ends the RRC connection process with base station 200 by two-stage random access (ST108). Note that if the data signal is decoded incorrectly or if it detects a collision with the RACH of another terminal, terminal 100 starts the random access again, for example, from the process in ST102.

[0078] [How to set up the sending resource for Data part] Next, an example of a method for configuring transmission resources for a data part in data resource configuration section 103 of terminal 100 and data resource configuration section 205 of base station 200 will be described.

[0079] In this embodiment, when block based interlace design is applied to the preamble part in two-stage random access, the transmission resource of the data part is set (in other words, derived) based on the transmission resource of the preamble part.

[0080] For example, the terminal 100 and the base station 200 derive the frequency resource and the time resource of the data part based on at least the preamble number and the interlace number of the preamble part. In other words, in two-stage random access, when block-based interlace design is applied to the preamble part, the data parts of multiple terminals are separated and multiplexed by frequency resources or time resources.

[0081] For example, as described below, preamble numbers and transmission resources of data parts are associated so that the transmission resources (e.g., cluster numbers, interlace numbers, or transmission symbol positions, etc.) of data parts corresponding to each of multiple preamble numbers are different from one another.

[0082] As a result, the preamble parts of multiple terminals 100 are code-multiplexed on the same interlace, and the data parts of multiple terminals 100 are frequency-multiplexed or time-multiplexed.

[0083] Furthermore, by using a different interlace number for the PRACH from other uplink channels that use block-based interlace design (e.g., PUSCH (Physical Uplink Shared Channel), PUCCH (Physical Uplink Control Channel), SRS (Sounding Reference Signal), etc.), the PRACH can be easily frequency-multiplexed with other uplink channels.

[0084] Furthermore, since the terminal 100 and the base station 200 derive the transmission resource for the Data part from a predetermined correspondence relationship with the Preamble part, it is possible to reduce the signaling for indicating the transmission resource for the Data part.

[0085] The correspondence between the transmission resource of the preamble part (for example, the preamble number) and the transmission resource of the data part may be specified in advance in a specification. This eliminates the need for new signaling for introducing two-stage random access. Alternatively, the correspondence between the transmission resource of the preamble part and the data part may be broadcast as cell information. In this case, the correspondence may be semi-statically updated according to the communication environment within the cell.

[0086] In addition to the derivation process described below, the transmission resource for the Data part may be derived using information notified from base station 200 to terminal 100.

[0087] Below, examples 1 to 7 of deriving the transmission resource of the Data part will be explained.

[0088] [Derivation example 1] FIG. 8 shows an example of the correspondence relationship between the transmission resources of the preamble part and the data part according to the derivation example 1.

[0089] In FIG. 8, as an example, one interlace (e.g., interlace number 0) in each of ten clusters (e.g., cluster numbers 0 to 9) is set as the transmission resource of the preamble part. In other words, the transmission resource of the preamble part is distributed across multiple bands (e.g., clusters #0 to #9). Also in FIG. 8, as an example, five preamble numbers 0 to 4 are set for terminal 100. Each preamble number is associated with a different code sequence (e.g., CS-ZC sequence). For example, terminal 100 randomly selects one preamble number from preamble numbers 0 to 4.

[0090] In addition, in Derivation Example 1, the interlace set in the preamble part (interlace number 0 in FIG. 8) is set in the transmission resource of the data part as shown in FIG. 8. Note that the interlace number set in the transmission resource of the data part may be different from the interlace number of the preamble part.

[0091] In addition, in Derivation Example 1, as shown in Fig. 8, the transmission resources of the Data part are allocated to some of the clusters set as the transmission resources of the preamble. In other words, the transmission resources of the Data part are limited to some of the clusters (or cluster numbers) set as the transmission resources of the preamble part. Also, as shown in Fig. 8, the some of the clusters set as the transmission resources of the Data part are associated with preamble numbers (in other words, code sequences) set for the preamble part. For example, as shown in Fig. 8, different cluster numbers are associated with each preamble number as the transmission resources of the Data part. In Fig. 8, as an example, the interval between the clusters associated with each preamble number is 5 clusters.

[0092] FIG. 9 shows an example of setting transmission resources for terminal 100 in Derivation Example 1.

[0093] In Fig. 9, the horizontal axis represents the frequency domain (or frequency resource allocation). For example, in Fig. 9, the interlace bandwidth is 1 PRB, the cluster bandwidth is 5 PRB (in other words, 5 interlaces), the interlace numbers are 0 to 4, and the cluster numbers are #0, #1, #2, .... Also, in Fig. 9, the vertical axis represents the time domain (e.g., time resource allocation). For example, in Fig. 9, it represents 2 symbols (in the case of OFDM (Orthogonal Frequency Division Multiplexing), an OFDM symbol including a CP (Cyclic Prefix)). Note that the length of one symbol of the preamble part and the data part may differ.

[0094] 9 shows an example in which terminal A (UE#A) selects preamble number 0 shown in FIG. 8, and terminal B (UE#B) selects preamble number 1 shown in FIG.

[0095] As shown in Fig. 9, each preamble part of terminal A and terminal B is allocated to the frequency band of interlace number 0 of each cluster. In this frequency band, different CS-ZC sequences associated with preamble number 0 and preamble number 1, respectively, are used for each preamble part of terminal A and terminal B. Therefore, each preamble part of terminal A and terminal B is code-multiplexed in the same interlace and can be separated in base station 200.

[0096] 9, the data part of terminal A is allocated to the frequency band with interlace number 0, which is the same as the preamble parts in clusters with cluster numbers 0 and 5. Similarly, as shown in FIG. 9, the data part of terminal B is allocated to the frequency band with interlace number 0, which is the same as the preamble parts in clusters with cluster numbers 1 and 6.

[0097] In this way, different clusters (or cluster numbers) are used for the transmission resources of each Data part of terminal A and terminal B. Therefore, the Data parts of terminal A and terminal B having different preamble numbers are frequency-multiplexed into orthogonal frequency resources and can be separated in base station 200.

[0098] Therefore, in Derivation Example 1, Data part signals transmitted from multiple terminals 100 can be frequency-multiplexed without new signaling related to the transmission resources of the Data parts.

[0099] Here, for example, there is a provision for temporary operation defined for IEEE802.11ax OFDMA (Orthogonal Frequency Division Multiple Access) signals (for example, a provision that "in the same COT (Channel Occupancy Time), if some signals satisfy the OCB provision of 80-100%, the bandwidth of some signals may be 2 MHz or more"). In contrast, in Derivation Example 1, for example, as shown in FIG. 8, since the preamble part signal satisfies the OCB provision of 80-100%, the bandwidth of the data part signal may be, for example, 2 MHz or more.

[0100] 8, the Data part signals of each terminal 100 are assigned to clusters with relatively distant cluster numbers (cluster interval: 5 in FIG. 8). This allows the terminal 100 to transmit the Data part signals over a wide band, resulting in frequency diversity gain and improved reception performance of the Data part signals.

[0101] It should be noted that the transmission resources for the Data part are not limited to the example shown in Fig. 8. For example, in the case of TDD (Time Division Duplexing), if terminal 100 can estimate uplink reception quality and identify clusters with good quality, Data part signals may be allocated to clusters with relatively close cluster numbers, as shown in Fig. 10. For example, in Fig. 10, the cluster numbers associated with each preamble number are consecutive numbers. This allows terminal 100 to select a cluster (in other words, a preamble number) that is expected to have good quality and transmit the Data part signal, thereby improving reception performance of the Data part signal.

[0102] Note that the transmission resources (for example, cluster numbers) of the Data part shown in FIGS. 8 and 10 are merely examples, and the cluster numbers associated with each Preamble number for the Data part are not limited to these.

[0103] [Derivation example 2] FIG. 11 shows an example of the correspondence relationship between the transmission resources of the preamble part and the data part according to the derivation example 2.

[0104] In FIG. 11, the transmission resources of the preamble part are the same as those in Derivation Example 1 (see, for example, FIG. 8 or FIG. 9).

[0105] In Derivation Example 2, as shown in Fig. 11, the interlace set in the preamble part (interlace number 0 in Fig. 11) is set in the transmission resource of the data part, as in Derivation Example 1. Note that the interlace number set in the transmission resource of the data part may be different from the interlace number of the preamble part.

[0106] In addition, in Derivation Example 2, the transmission resources of the Data part are allocated to some of the clusters set as the transmission resources of the preamble in the frequency domain, as in Derivation Example 1. Furthermore, in Derivation Example 2, the transmission resources of the Data part are allocated to three symbols (Sym#0, Sym#1, and Sym#2) in the time domain, as shown in Fig. 11.

[0107] In Derivation Example 2, as shown in Fig. 11, the part of clusters set in the transmission resources of the Data part are associated with preamble numbers (in other words, code sequences) set for the preamble part. At this time, the part of clusters set in the transmission resources of the Data part are different for each of a plurality of symbols (Sym#0, Sym#1, and Sym#2 in Fig. 11). For example, as shown in Fig. 11, each preamble number is associated with a different cluster number for each symbol as the transmission resource of the Data part.

[0108] FIG. 12 shows an example of setting transmission resources for terminal 100 in Derivation Example 2.

[0109] In Fig. 12, the horizontal axis represents the frequency domain (or frequency resource allocation), and the vertical axis represents the time domain (for example, time resource allocation). The configuration of clusters and interlaces within clusters shown in Fig. 12 is the same as that in Derivation Example 1 (for example, Fig. 9). However, in Fig. 12, one symbol is set in the preamble part and three symbols are set in the data part in the time domain.

[0110] 12 shows an example in which terminal A (UE#A) selects preamble number 0 shown in FIG. 11, and terminal B (UE#B) selects preamble number 1 shown in FIG.

[0111] As shown in Figure 12, the preamble parts of terminal A and terminal B are allocated to the frequency band of interlace number 0 in each cluster, as in Figure 9, and different CS-ZC sequences associated with preamble number 0 and preamble number 1 are used.

[0112] Also, as shown in FIG. 12, the Data part of terminal A is allocated to the frequency band with interlace number 0, which is the same as the Preamble parts in clusters with cluster numbers 0 and 5, in symbol 0 (Sym#0), to the frequency band with interlace number 0, which is the same as the Preamble parts in clusters with cluster numbers 2 and 7 (cluster number 6 is not shown), in symbol 1 (Sym#1), and to the frequency band with interlace number 0, which is the same as the Preamble parts in clusters with cluster numbers 4 and 9 (cluster number 9 is not shown), in symbol 2 (Sym#2).

[0113] Similarly, as shown in FIG. 12, the Data part of terminal B is allocated to the frequency band with interlace number 0, which is the same as the Preamble parts in clusters with cluster numbers 1 and 6, in symbol 0 (Sym#0), to the frequency band with interlace number 0, which is the same as the Preamble parts in clusters with cluster numbers 3 and 8 (cluster number 8 is not shown), in symbol 1 (Sym#1), and to the frequency band with interlace number 0, which is the same as the Preamble parts in clusters with cluster numbers 0 and 5, in symbol 2 (Sym#2).

[0114] In this way, different clusters (or cluster numbers) are used in each symbol for the transmission resources of each Data part of terminal A and terminal B. Therefore, the Data parts of terminal A and terminal B having different preamble numbers are frequency-multiplexed into orthogonal frequency resources in each symbol, and can be separated in base station 200.

[0115] Furthermore, in Derivation Example 2, the Data part signal of each terminal 100 is frequency hopped among a plurality of symbols, and therefore the reception performance of the Data part signal can be improved by frequency diversity gain.

[0116] Although FIG. 12 shows an example in which the Data part signal of each terminal 100 is frequency hopped among a plurality of symbols, the Data part signal of each terminal 100 may be allocated to the same frequency band in a plurality of symbols.

[0117] [Derivation example 3] FIG. 13 shows an example of the correspondence relationship between the transmission resources of the preamble part and the data part according to the derivation example 3.

[0118] In Fig. 13, the transmission resources of the preamble part are the same as those in Derivation Example 1 (see, for example, Fig. 8 or 9). However, in Fig. 13, as an example, ten preamble numbers 0 to 9 are set for terminal 100. Each preamble number is associated with a different code sequence (for example, a CS-ZC sequence). For example, terminal 100 randomly selects one preamble number from preamble numbers 0 to 9.

[0119] In addition, in Derivation Example 3, as shown in Figure 13, the transmission resources of the Data part are set to the interlace set in the Preamble part (interlace number 0 in Figure 13) and some of the clusters (or cluster numbers) set in the Preamble part, as in Derivation Example 1 (see, for example, Figure 8 or Figure 9).

[0120] Furthermore, in Derivation Example 3, at least one sub-PRB included in the set cluster is set as the transmission resource of the Data part.

[0121] Here, a sub-PRB is, for example, a resource unit obtained by dividing one PRB (12 subcarriers in LTE or NR) into one or more subcarriers (for example, four or six subcarriers). In other words, a sub-PRB is a resource unit included in each interlace of multiple clusters in the transmission resources of the preamble part. Note that the number of subcarriers constituting one PRB (or one interlace in each cluster) is not limited to 12 subcarriers, and the number of subcarriers constituting a sub-PRB (in other words, the number of divisions of one PRB) is not limited to four or six subcarriers. The sub-PRB shown in FIG. 13 is a resource unit obtained by dividing one PRB into two.

[0122] For example, as shown in FIG. 13, the transmission resources of the Data part include at least one sub-PRB among the sub-PRBs included in the cluster in which the transmission resources of the Preamble part are arranged.

[0123] At least one sub-PRB set in the transmission resources of the Data part is associated with a preamble number (in other words, a code sequence) set for the preamble part. At this time, different sub-PRB numbers are associated with multiple preamble numbers for which the same cluster number is set in the transmission resources of the Data part. For example, in Fig. 13, sub-PRB number 0 (sub-PRB#0) and sub-PRB number 1 (sub-PRB#1) are associated with the pair of preamble numbers 0 and 1, respectively. The same applies to other pairs of preamble numbers associated with the same cluster number.

[0124] In other words, each preamble number shown in FIG. 13 is associated with a resource having a different cluster number or sub-PRB number as a transmission resource for the data part.

[0125] FIG. 14 shows an example of setting transmission resources for the terminal 100 in the third derivation example.

[0126] In Fig. 14, the horizontal axis represents the frequency domain (or frequency resource allocation), and the vertical axis represents the time domain (e.g., time resource allocation). The configuration of the clusters and interlaces within the clusters shown in Fig. 14 is the same as that in Derivation Example 1 (e.g., Fig. 9). However, in Fig. 14, each PRB (e.g., 12 subcarriers #0 to #11) is made up of sub-PRB#0 (e.g., subcarriers #0 to #5) and sub-PRB#1 (e.g., subcarriers #6 to #11).

[0127] 14 shows an example in which terminal A (UE#A) selects preamble number 0 shown in FIG. 13, and terminal B (UE#B) selects preamble number 1 shown in FIG.

[0128] As shown in Figure 14, the preamble parts of terminal A and terminal B are allocated to the frequency band of interlace number 0 in each cluster, as in Figure 9, and different CS-ZC sequences associated with preamble number 0 and preamble number 1 are used.

[0129] 14, the data part of terminal A is allocated to sub-PRB#0 with the same interlace number 0 as the preamble parts in clusters with cluster numbers 0 and 5. Similarly, as shown in FIG. 14, the data part of terminal B is allocated to sub-PRB#1 with the same interlace number 0 as the preamble parts in clusters with cluster numbers 0 and 5.

[0130] In this way, frequency resources with different cluster numbers and / or different sub-PRB numbers are used as transmission resources for each Data part of terminal A and terminal B. Therefore, each Data part of terminal A and terminal B with different preamble numbers is frequency-multiplexed into orthogonal frequency resources in interlaces with the same number, for example, and can be separated in base station 200.

[0131] In addition, in Derivation Example 3, it is possible to allocate Data part signals of different terminals 100 in sub-PRB units even to the same interlace of the same cluster, as shown in Fig. 14. In this way, according to Derivation Example 3, by allocating Data part signals in sub-PRB units, it is possible to increase the number of PRACHs that can be allocated to the same interlace, and reduce the collision rate of random access.

[0132] [Derivation example 4] FIG. 15 shows an example of the correspondence relationship between the transmission resources of the preamble part and the data part according to the derivation example 4.

[0133] In FIG. 15, the transmission resources of the preamble part are the same as those in Derivation Example 1 (see, for example, FIG. 8 or FIG. 9).

[0134] In Derivation Example 4, each of the plurality of clusters to which the preamble part and the data part are assigned is made up of a plurality of subcarriers (also called combs or tones, for example).

[0135] For example, numbers (e.g., subcarrier numbers, Com numbers, or Tone numbers) are assigned to multiple subcarriers in resource units of each of multiple clusters in the transmission resources of the preamble part (in other words, in interlace units within a cluster). For example, in Fig. 15, each interlace within a cluster includes five subcarriers (Comb numbers 0 to 4).

[0136] In Derivation Example 4, as shown in Fig. 15, frequency resources are set in subcarrier units as transmission resources for the Data part. For example, the transmission resources for the Data part include subcarriers with the same Comb number in multiple clusters. The Comb number included in the transmission resources for the Data part is associated with a Preamble number (in other words, a code sequence) set for the Preamble part.

[0137] 15, for example, different comb numbers 0 to 4 are associated with the preamble numbers 0 to 4. In other words, the transmission resources of the data part are allocated by interlace allocation in subcarrier units (for example, called tone-interlace design or IFDMA (Interleaved Frequency Division Multiple Access)).

[0138] FIG. 16 shows an example of setting transmission resources for terminal 100 in Derivation Example 4.

[0139] In Fig. 16, the horizontal axis represents the frequency domain (or frequency resource allocation), and the vertical axis represents the time domain (for example, time resource allocation). In addition, the configuration of clusters and interlaces within clusters in the symbols to which the preamble parts shown in Fig. 16 are allocated is the same as that in Derivation Example 1 (for example, Fig. 9).

[0140] On the other hand, in Fig. 16, in the symbol to which the Data part is assigned, each PRB includes five Combs #0 to #4 (subcarriers or subcarrier groups). Note that the number of Combs constituting a PRB is not limited to five, and may be any other number.

[0141] 16 shows an example in which terminal A (UE#A) selects preamble number 0 shown in FIG. 15, and terminal B (UE#B) selects preamble number 1 shown in FIG.

[0142] As shown in Figure 16, the preamble parts of terminal A and terminal B are allocated to the frequency band of interlace number 0 in each cluster, as in Figure 9, and different CS-ZC sequences associated with preamble number 0 and preamble number 1 are used.

[0143] 16, the data part of terminal A is allocated to the comb (or subcarrier) with comb number 0 in each of interlaces #0 to #4 in each cluster. Similarly, as shown in FIG. 16, the data part of terminal B is allocated to the comb (or subcarrier) with comb number 1 in each of interlaces #0 to #4 in each cluster.

[0144] In this way, the data parts of terminal A and terminal B, which have different preamble numbers, are frequency-multiplexed onto orthogonal frequency resources and can be separated in base station 200.

[0145] Furthermore, in Derivation Example 4, the Data part signals of each terminal 100 are allocated to multiple interlaces in each cluster. In other words, the Data part signals of each terminal 100 are allocated to each cluster to which the Preamble part signals are allocated. Therefore, the Data part signals of each terminal 100 are allocated across the same band as the Preamble part signals (clusters #0 to #9 in FIG. 16).

[0146] Regarding signal transmission in unlicensed bands, the ETSI (European Telecommunications Standards Institute) has established the "OCB Regulations," which state that signals should be transmitted in a bandwidth that is 80-100% of the carrier sense band (or a band that is an integer multiple of 20 MHz, also known as a subband).

[0147] In Derivation Example 4, for example, as shown in FIG. 16, both the preamble part and the data part are transmitted using clusters with cluster numbers 0 to 9, so that the OCB specification of 80-100% can be satisfied.

[0148] [Derivation example 5] FIG. 17 shows an example of the correspondence relationship between the transmission resources of the preamble part and the data part according to the derivation example 5.

[0149] In Fig. 17, the transmission resources of the preamble part are the same as those in Derivation Example 1 (see, for example, Fig. 8 or 9). However, in Fig. 17, as an example, ten preamble numbers 0 to 9 are set for terminal 100. Each preamble number is associated with a different code sequence (for example, a CS-ZC sequence). For example, terminal 100 randomly selects one preamble number from preamble numbers 0 to 9.

[0150] In addition, in Derivation Example 5, as shown in FIG. 17, the transmission resources of the Data part are set in the frequency domain to the interlace set in the Preamble part (interlace number 0 in FIG. 17) and some of the clusters (or cluster numbers) set in the Preamble part, as in Derivation Example 1 (see, for example, FIG. 8 or FIG. 9).

[0151] Furthermore, in Derivation Example 5, at least one symbol out of a plurality of symbols (two symbols in FIG. 17) is set as the transmission resource of the Data part in the time domain.

[0152] At least one symbol set in the transmission resource of the Data part is associated with a preamble number (in other words, a code sequence) set for the preamble part. At this time, as shown in Fig. 17, different symbol numbers (symbol numbers 0 and 1) are associated with multiple preamble numbers for which the same cluster number is set in the transmission resource of the Data part. For example, in Fig. 17, symbol number 0 and symbol number 1 are associated with the pair of preamble numbers 0 and 1, respectively. The same applies to other pairs of preamble numbers associated with the same cluster number. In other words, each preamble number shown in Fig. 17 is associated with a resource having a different cluster number or symbol number as the transmission resource of the Data part.

[0153] FIG. 18 shows an example of setting transmission resources for terminal 100 in Derivation Example 5.

[0154] In Fig. 18, the horizontal axis represents the frequency domain (or frequency resource allocation), and the vertical axis represents the time domain (for example, time resource allocation). The configuration of clusters and interlaces within clusters shown in Fig. 18 is the same as that in Derivation Example 1 (for example, Fig. 9). However, in Fig. 18, one symbol is set in the preamble part in the time domain, and multiple symbols (two symbols in Fig. 18) are set in the data part.

[0155] 18 shows an example in which terminal A (UE#A) selects preamble number 0 shown in FIG. 17, and terminal B (UE#B) selects preamble number 1 shown in FIG.

[0156] As shown in Figure 18, the preamble parts of terminal A and terminal B are allocated to the frequency band of interlace number 0 in each cluster, as in Figure 9, and different CS-ZC sequences associated with preamble number 0 and preamble number 1 are used.

[0157] 18, the data part of terminal A is assigned to the symbol (Sym#0) with symbol number 0 of the same interlace number 0 as the preamble parts in the clusters with cluster numbers 0 and 5. Similarly, as shown in FIG. 18, the data part of terminal B is assigned to the symbol (Sym#1) with symbol number 1 of the same interlace number 0 as the preamble parts in the clusters with cluster numbers 0 and 5.

[0158] In this way, resources with different cluster numbers and / or different symbol numbers are used as transmission resources for each Data part of terminal A and terminal B. Therefore, each Data part of terminal A and terminal B with different preamble numbers is time-multiplexed into symbols that are orthogonal time resources in interlaces with the same number, for example, and can be separated in base station 200.

[0159] In addition, in Derivation Example 5, for example, compared to Derivation Example 1, the time resources (e.g., the number of symbols) for transmitting Data part signals are increased, which increases the number of PRACHs that can be assigned to the same interlace and reduces the collision rate of random access.

[0160] [Derivation example 6] FIG. 19 shows an example of the correspondence relationship between the transmission resources of the preamble part and the data part according to the derivation example 6.

[0161] In Fig. 19, the transmission resources of the preamble part are the same as those in Derivation Example 1 (see, for example, Fig. 8 or 9). However, in Fig. 19, as an example, four preamble numbers 0 to 3 are set for terminal 100. Each preamble number is associated with a different code sequence (for example, a CS-ZC sequence). For example, terminal 100 randomly selects one preamble number from preamble numbers 0 to 3.

[0162] In addition, in Derivation Example 6, the preamble part and the data part are frequency-multiplexed onto different interlaces within the same symbol.

[0163] For example, as shown in Fig. 19, in each cluster set in the preamble part, an interlace (or interlace number) different from the interlace set in the preamble part (interlace number 0 in Fig. 19) is set in the transmission resource of the data part. The interlace to which the transmission resource of the data part is set corresponds to the preamble number (in other words, code sequence) set for the preamble part. In this case, the data parts of terminals 100 using different preamble numbers are frequency-multiplexed into different interlaces in the same symbol.

[0164] As shown in FIG. 19, the transmission resources of the Data part are set to the same clusters (or cluster numbers) as the clusters (cluster numbers 0 to 9 in FIG. 19) set to the Preamble part.

[0165] FIG. 20 shows an example of setting transmission resources for terminal 100 in Derivation Example 6.

[0166] In Fig. 20, the horizontal axis represents the frequency domain (or frequency resource allocation), and the vertical axis represents the time domain (for example, time resource allocation). The configuration of clusters and interlaces within clusters shown in Fig. 20 is the same as that in Derivation Example 1 (for example, Fig. 9). However, in Fig. 20, one symbol is set for both the preamble part and the data part in the time domain.

[0167] 20 shows an example in which terminal A (UE#A) selects preamble number 0 shown in FIG. 19, and terminal B (UE#B) selects preamble number 1 shown in FIG.

[0168] As shown in Figure 20, the preamble parts of terminal A and terminal B are allocated to the frequency band of interlace number 0 in each cluster, as in Figure 9, and different CS-ZC sequences associated with preamble number 0 and preamble number 1 are used.

[0169] 20, the data part of terminal A is allocated to the frequency band of interlace number 1 in each cluster, and the data part of terminal B is allocated to the frequency band of interlace number 2 in each cluster.

[0170] In this way, the preamble parts of terminal A and terminal B and the data parts of terminal A and terminal B having different preamble numbers are frequency-multiplexed into orthogonal frequency resources and can be separated in base station 200. In other words, multiple terminals 100 can transmit preamble parts and data parts using the same symbol.

[0171] Therefore, according to Derivation Example 6, by frequency-multiplexing the preamble part and the data part, it is possible to reduce the delay time required for random access.

[0172] In addition, in Derivation Example 6, for example, as shown in FIG. 20, both the preamble part and the data part are transmitted using clusters with cluster numbers 0 to 9, so similar to Derivation Example 4, the 80-100% OCB specification can be met.

[0173] [Derivation example 7] FIG. 21 shows an example of the correspondence relationship between the transmission resources of the preamble part and the data part according to the seventh derivation example.

[0174] In Fig. 21, the transmission resources of the preamble part are the same as those in Derivation Example 1 (see, for example, Fig. 8 or 9). However, in Fig. 21, as an example, four preamble numbers 0 to 3 are set for terminal 100. Each preamble number is associated with a different code sequence (for example, a CS-ZC sequence). For example, terminal 100 randomly selects one preamble number from preamble numbers 0 to 3.

[0175] In addition, in Derivation Example 7, similarly to Derivation Example 1, the transmission resources of the Data part are allocated to some of the clusters among the multiple clusters set for the transmission resources of the Preamble. For example, as shown in Fig. 21, each Preamble number is associated with a cluster having a different cluster number for the transmission resources of the Data part.

[0176] Furthermore, in Derivation Example 7, the number of clusters for transmission resources of the Data part associated with the preamble number differs for each preamble (in other words, for each code sequence used in the preamble part signal), as shown in Fig. 21. For example, as shown in Fig. 21, three clusters (or cluster numbers) are associated with preamble numbers 0 and 1, respectively, whereas two clusters (or cluster numbers) are associated with preamble numbers 2 and 3, respectively.

[0177] For example, a preamble number that can be selected by the terminal 100 may be set according to the reception quality of the terminal 100. The reception quality of the terminal 100 may be, for example, a path loss level between the terminal 100 (UE) and the base station 200 (gNB), a received signal level (for example, Received Signal Reception Power (RSRP)), or another parameter.

[0178] 21, terminal 100 may be able to select, for example, preamble numbers 0 and 1 when the path loss level is greater than threshold value X, and may be able to select preamble numbers 2 and 3 when the path loss level is equal to or less than threshold value X. Note that FIG. 21 is just an example, and the number of clusters associated with preamble numbers in the transmission resources of the Data part is not limited to two or three, and the number of types of clusters associated with preamble numbers is not limited to two, but may be three or more.

[0179] FIG. 22 shows an example of setting transmission resources for terminal 100 in Derivation Example 7.

[0180] In Fig. 22, the horizontal axis represents the frequency domain (or frequency resource allocation), and the vertical axis represents the time domain (for example, time resource allocation). The configuration of clusters and interlaces within clusters shown in Fig. 22 is the same as in Fig. 9.

[0181] FIG. 22 also shows an example in which terminal A (UE#A) has a path loss level greater than threshold X and randomly selects preamble number 0 shown in FIG. 21, and terminal B (UE#B) has a path loss level less than threshold X and randomly selects preamble number 2 shown in FIG. 21.

[0182] As shown in Figure 22, the preamble parts of terminal A and terminal B are allocated to the frequency band of interlace number 0 in each cluster, as in Figure 9, and different CS-ZC sequences associated with preamble number 0 and preamble number 1 are used.

[0183] 22, the data part of terminal A is allocated to sub-PRB#0 with the same interlace number 0 as the preamble parts in three clusters, cluster numbers 0, 3, and 5. Also, as shown in FIG. 22, the data part of terminal B is allocated to sub-PRB#1 with the same interlace number 0 as the preamble parts in two clusters, cluster numbers 2 and 7.

[0184] In this way, the data parts of terminal A and terminal B, which have different preamble numbers, are frequency-multiplexed onto orthogonal frequency resources and can be separated in base station 200.

[0185] For example, the amount of data transmitted in the Data part is constant. Therefore, as the number of clusters for transmitting the Data part increases, the coding rate of the Data part decreases, and performance improves. Therefore, for example, as shown in Fig. 22, terminal A, whose path loss level is greater than threshold X, can improve the performance of the Data part by transmitting the Data part using more clusters than terminal B, whose path loss level is equal to or less than threshold X.

[0186] Therefore, according to Derivation Example 7, by appropriately changing the amount of frequency resources for transmitting a Data part signal or the coding rate in accordance with the reception quality (for example, path loss level) of terminal 100, it is possible to improve the performance of the Data part.

[0187] The above has explained examples 1 to 7 of deriving the transmission resource of the Data part.

[0188] It is also possible to combine at least two of the above-described Derivation Examples 1 to 7. For example, by combining Derivation Example 2 and Derivation Example 3, it is possible to obtain a frequency diversity effect for the Data part, increase the number of PRACHs that can be allocated in the same interlace, and reduce the collision rate of random access.

[0189] Alternatively, terminal 100 and base station 200 may switch between at least two of derivation examples 1 to 7 depending on the setting of terminal 100 (or the situation of terminal 100), for example.

[0190] As described above, in this embodiment, resources used for transmitting a Data part are determined based on resources used for transmitting a Preamble part. For example, a Preamble number selectable by terminal 100 is associated with a transmission resource for the Data part (e.g., a cluster number, an interlace number, a sub-PRB number, a Comb number, or a symbol number) in addition to a transmission resource for the Preamble part (e.g., a cluster number and an interlace number).

[0191] This allows the terminal 100 and base station 200 to identify transmission resources for both the preamble part and the data part according to the set preamble number. Furthermore, the preamble parts transmitted from multiple terminals 100 are code-multiplexed, and the data parts transmitted from multiple terminals 100 are frequency-multiplexed or time-multiplexed.

[0192] Therefore, according to this embodiment, the random access process can be performed appropriately.

[0193] The embodiments of the present disclosure have been described above.

[0194] (Other embodiments) (1) In the above embodiment, the operation in an unlicensed band has been described. However, the present disclosure is not limited to the unlicensed band and can also be applied to a licensed band, and similar effects can be obtained. For example, the present disclosure can be applied to grant-free transmission in which transmission resources are predefined in a licensed band, or to transmission of a URLLC service, and the present disclosure can reduce delay time or improve performance.

[0195] (2) In the above embodiment, the correspondence between the preamble number and the transmission resources of the preamble part and the data part is defined, for example, in the tables shown in Figures 8, 10, 11, 13, 15, 17, 19, and 21, but is not limited to this and may be defined, for example, by an equation.

[0196] As an example, in the derivation example 2 (see, for example, FIG. 11), the cluster numbers (represented as C0, C1, and C2) for each symbol (symbol number) in the transmission resources of the Data part are expressed by the following equations. C0 = P, P + N / 2 C1 = P + 2 , mod(P + 2 +N / 2, N) C2 = P + 4 , mod(P + 4 +N / 2, N) however, C0: Cluster number used for symbol number 0 of Data part (any of 0 to N-1) C1: Cluster number used for symbol number 1 of Data part (any of 0 to N-1) C2: Cluster number used in symbol number 2 of Data part (any of 0 to N-1) P: Preamble number (e.g., 0 to 4 in Figure 11) N: Number of clusters (e.g., N=10 in Figure 11)

[0197] (3) Resources (e.g., free resources) other than the transmission resources of the PRACH (e.g., preamble part and data part) described in the above embodiments may be set to, for example, another RACH resource (RACH occasion) or may be used for scheduling another uplink channel (e.g., PUSCH, PUCCH, SRS).

[0198] (4) In the above embodiment, the PRACH has been described as an example of a transmission signal. However, the transmission signal is not limited to the PRACH. For example, the transmission signal may be another signal transmitted from the terminal 100 (corresponding to the transmitting device) to the base station 200 (corresponding to the receiving device), or may be a transmission signal transmitted from the base station 200 (corresponding to the transmitting device) to the terminal 100 (corresponding to the receiving device).

[0199] (5) Interlaces may be expressed, for example, by the number of interlaces in a certain band (e.g., represented as M, corresponding to the number of interlaces in a cluster) and the number of PRBs constituting each interlace (e.g., represented as N, corresponding to the number of clusters). Furthermore, each interlace is not limited to being distributed and arranged in units of PRBs in the frequency domain, but may be distributed and arranged in units consisting of a subcarrier group that is smaller than the subcarriers constituting one PRB. Furthermore, the frequency intervals of the resources in which each interlace is arranged are not limited to being equal intervals.

[0200] (6) The number of clusters in a specific frequency band (e.g., system band), the number of interlaces in each cluster, and the number of subcarriers per interlace (or PRB) are not limited to those exemplified in the above embodiments, and may be other values.

[0201] (7) In the above embodiment, the block-based interlace design may be referred to as a "PRB-based interlace design." An interlace may also be referred to as a "cluster." A cluster may also be referred to as a "cluster block." For example, it may be expressed that a cluster block contains multiple clusters.

[0202] Other embodiments have been described above.

[0203] The present disclosure can be realized by software, hardware, or software in conjunction with hardware. Each functional block described in the above embodiments may be partially or entirely realized as an LSI, which is an integrated circuit. Each process described in the above embodiments may be partially or entirely controlled by a single LSI or a combination of LSIs. An LSI may be composed of individual chips, or may be composed of a single chip that includes some or all of the functional blocks. An LSI may have data inputs and outputs. Depending on the level of integration, an LSI may be referred to as an IC, system LSI, super LSI, or ultra LSI. The integration method is not limited to LSIs; it may also be realized by dedicated circuits, general-purpose processors, or dedicated processors. Furthermore, a field programmable gate array (FPGA), which can be programmed after LSI fabrication, or a reconfigurable processor, which allows the connections and settings of circuit cells within an LSI to be reconfigured, may also be used. The present disclosure may be realized as digital or analog processing. Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derivative technologies, it is natural that such technology can be used to integrate functional blocks. The application of biotechnology is also a possibility.

[0204] The present disclosure may be implemented in any type of apparatus, device, or system with communications capabilities (collectively referred to as communications apparatus), including, but not limited to, telephones (e.g., cell phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still / video cameras), digital players (e.g., digital audio / video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), game consoles, digital book readers, telehealth / telemedicine devices, communications-enabled vehicles or mobile transportation (e.g., cars, airplanes, ships), and combinations of the above.

[0205] Communications equipment is not limited to portable or mobile equipment, but also includes non-portable or fixed equipment, devices, and systems of any kind, such as smart home devices (such as appliances, lighting equipment, smart meters or metering devices, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0206] Communications include data communications via cellular systems, wireless LAN systems, communications satellite systems, etc., as well as data communications via combinations of these.

[0207] A communications apparatus also includes devices such as controllers and sensors connected or coupled to a communications device that performs the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications device to perform the communications functions of the communications apparatus.

[0208] The communication apparatus also includes infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicates with or controls the various apparatuses listed above, but are not limited to these.

[0209] A transmitting device in one embodiment of the present disclosure includes a transmitting circuit that transmits a data signal, and a control circuit that determines a second resource to be used for transmitting the data signal based on a first resource to be used for transmitting a preamble signal.

[0210] In a transmission device according to an embodiment of the present disclosure, the first resources are distributed among a plurality of bands, and the second resources are allocated to a portion of the plurality of bands.

[0211] In the transmitting device according to an embodiment of the present disclosure, the partial band is associated with a code sequence set for the preamble signal.

[0212] In a transmitting device according to an embodiment of the present disclosure, the partial band differs for each of a plurality of symbols in which the second resource is allocated.

[0213] In a transmitting device according to one embodiment of the present disclosure, each resource of the plurality of bands in the first resource includes a plurality of resource units, the second resource includes at least one resource unit of the plurality of resource units included in the partial band, and the at least one resource unit is associated with a code sequence set for the preamble signal.

[0214] In a transmitting device according to one embodiment of the present disclosure, the second resource includes at least one symbol among a plurality of symbols, and the at least one symbol corresponds to a code sequence set for the preamble signal.

[0215] In a transmitting device according to an embodiment of the present disclosure, the number of bands included in the partial bands varies depending on the code sequence set for the preamble signal.

[0216] In a transmitting device according to one embodiment of the present disclosure, each of the plurality of bands is composed of a plurality of subcarriers, and numbers are assigned to the plurality of subcarriers in resource units for each of the plurality of bands in the first resource, the second resource includes the subcarriers with the same numbers within the plurality of bands, and the numbers of the subcarriers included in the second resource correspond to a code sequence set for the preamble signal.

[0217] In a transmitting device according to one embodiment of the present disclosure, the data signal and the preamble signal are frequency-multiplexed, the first resources are distributed across a plurality of bands, the second resources include resources in each of the plurality of bands that are different from the first resources, and the second resources correspond to a code sequence set in the preamble signal.

[0218] A receiving device in one embodiment of the present disclosure includes a receiving circuit that receives a data signal, and a control circuit that determines resources to be used for transmitting the data signal based on resources to be used for transmitting a preamble signal.

[0219] A transmission method according to an embodiment of the present disclosure determines resources to be used for transmitting a data signal based on resources to be used for transmitting a preamble signal, and transmits the data signal.

[0220] A receiving method according to an embodiment of the present disclosure determines resources to be used for transmitting a data signal based on resources to be used for transmitting a preamble signal, and receives the data signal.

[0221] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2018-206734, filed November 1, 2018, are incorporated herein by reference in their entirety. [Industrial Applicability]

[0222] An embodiment of the present disclosure is useful in a mobile communication system. [Explanation of symbols]

[0223] 100 devices 101,203 Control unit 102,204 Preamble resource setting section 103,205 Data resource setting section 104 Preamble generation section 105 Preamble resource allocation section 106 Data generation section 107 Data Resource Allocation Department 108,211 Radio transmitter 109,201 antennas 110,202 Radio receiver 111,207 Demodulation and Decoding Section 200 base stations 206 Preamble detection unit 208 Scheduling Department 209 Data Generation Department 210 Encoding and Modulation Section

Claims

1. A control circuit for selecting a random access preamble from a first plurality of random access preambles when the path loss between a communication device and a base station is smaller than a threshold value, and selecting a random access preamble from a second plurality of random access preambles when the path loss between the communication device and the base station is equal to or greater than the threshold value, in a two-stage random access; a transmitter that transmits the selected random access preamble and transmits data using an interlace with an interlace number associated with the selected random access preamble; a first plurality of interlace numbers associated with the first plurality of random access preambles are contiguous, a second plurality of interlace numbers associated with the second plurality of random access preambles are contiguous, and the first plurality of interlace numbers are different from the second plurality of interlace numbers; Communication equipment.

2. the first plurality of random access preambles and the second plurality of random access preambles are generated based on different code sequences, respectively; The communication device according to claim 1 .

3. the resources indicated by the first plurality of interlace numbers or the second plurality of interlace numbers are distributed and arranged in a frequency domain; The communication device according to claim 1 .

4. the transmitter transmits a data signal in a random access procedure using resources indicated by the first plurality of interlace numbers or the second plurality of interlace numbers; The communication device according to claim 1 .

5. a portion of the resources in each of the first plurality of interlace numbers and a portion of the resources in each of the second plurality of interlace numbers are arranged within a cluster of physical resource blocks. The communication device according to claim 1 .

6. In two-stage random access, when a path loss between a communication device and a base station is smaller than a threshold, a random access preamble is selected from a first plurality of random access preambles, and when a path loss between the communication device and the base station is equal to or greater than the threshold, a random access preamble is selected from a second plurality of random access preambles; transmitting the selected random access preamble and transmitting data using an interlace having an interlace number associated with the selected random access preamble; a first plurality of interlace numbers associated with the first plurality of random access preambles are contiguous, a second plurality of interlace numbers associated with the second plurality of random access preambles are contiguous, and the first plurality of interlace numbers are different from the second plurality of interlace numbers; Communication method.

7. the first plurality of random access preambles and the second plurality of random access preambles are generated based on different code sequences, respectively; The communication method according to claim 6.

8. the resources indicated by the first plurality of interlace numbers or the second plurality of interlace numbers are distributed and arranged in a frequency domain; The communication method according to claim 6.

9. transmitting a data signal in a random access procedure using resources indicated by the first plurality of interlace numbers or the second plurality of interlace numbers; The communication method according to claim 6.

10. a portion of the resources in each of the first plurality of interlace numbers and a portion of the resources in each of the second plurality of interlace numbers are arranged within a cluster of physical resource blocks. The communication method according to claim 6.

11. In two-stage random access, a process of selecting a random access preamble from a first plurality of random access preambles when the path loss between a communication device and a base station is smaller than a threshold, and selecting a random access preamble from a second plurality of random access preambles when the path loss between the communication device and the base station is equal to or greater than the threshold; transmitting the selected random access preamble and transmitting data using an interlace with an interlace number associated with the selected random access preamble; a first plurality of interlace numbers associated with the first plurality of random access preambles are contiguous, a second plurality of interlace numbers associated with the second plurality of random access preambles are contiguous, and the first plurality of interlace numbers are different from the second plurality of interlace numbers; Integrated circuit.

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