Transmission device, reception device, transmission method, and reception method

Abstract

The invention provides a transmitting device, a receiving device, a transmitting method and a receiving method. The transmission device is provided with: a transmission circuit that transmits a random access channel signal; and a control circuit that sets a preamble sequence for the signal from among a plurality of candidate preamble sequences, the preamble sequence being transmitted at least at a first RACH timing and a second RACH timing, and the number of ZC (Zadoff-Chu) sequences included in the preamble sequence being different for each cell.

Description

[0001] This application is a divisional application of the invention patent application with national application number 202080023943.X, international application date March 24, 2020, date of entry into the Chinese national phase September 24, 2021, and invention name “Sending device and sending method”. Technical Field

[0002] The present disclosure relates to a sending device, a receiving device, a sending method and a receiving method. Background Art

[0003] In terms of 5G standardization, the 3rd Generation Partnership Project (3GPP) has discussed the new radio access technology (NR) and released the specifications of NR Release (Rel.) 15.

[0004] In wireless communication systems such as NR, a random access procedure using a random access channel is performed to connect a terminal (also called "UE (User Equipment)") and a base station (also called "gNB (gNodeB)").

[0005] Prior art literature

[0006] Patent Literature

[0007] Non-patent document 1: 3GPP, TR38.811, "Study on New Radio (NR) to support nonterrestrial networks"

[0008] Non-patent document 2: 3GPP TS38.321, "Medium Access Control (MAC) protocol specification" Summary of the invention

[0009] However, there is still room for research on an appropriate random access procedure corresponding to the propagation delay between the terminal and the base station.

[0010] The non-limiting embodiments of the present disclosure help to provide a transmitting apparatus, a receiving apparatus, a transmitting method, and a receiving method that can implement an appropriate random access procedure corresponding to a propagation delay between a terminal and a base station.

[0011] A transmitting device according to an embodiment of the present disclosure includes: a transmitting circuit for transmitting a signal of a random access channel; and a control circuit for setting a preamble code sequence for the signal from a plurality of candidate preamble code sequences, wherein at least one of the plurality of candidate preamble code sequences is composed of two or more code sequences that are different from each other.

[0012] A receiving device of an embodiment of the present disclosure includes: a receiving circuit, which receives a signal of a random access channel; and a control circuit, which determines a preamble code sequence contained in the signal from a plurality of candidate preamble code sequences, wherein at least one candidate preamble code sequence among the plurality of candidate preamble code sequences is composed of two or more code sequences that are different from each other.

[0013] A sending method according to an embodiment of the present disclosure sets a preamble code sequence for a signal of a random access channel from a plurality of candidate preamble code sequences; and sends the signal of the random access channel, wherein at least one of the plurality of candidate preamble code sequences is composed of two or more code sequences that are different from each other.

[0014] A receiving method according to an embodiment of the present disclosure receives a signal of a random access channel; and determines a preamble code sequence contained in the signal from a plurality of candidate preamble code sequences, wherein at least one candidate preamble code sequence among the plurality of candidate preamble code sequences is composed of two or more code sequences that are different from each other.

[0015] These general or specific aspects may be implemented by a system, an apparatus, a method, an integrated circuit, a computer program or a recording medium, or may be implemented by any combination of systems, apparatuses, methods, integrated circuits, computer programs and recording media.

[0016] According to one embodiment of the present disclosure, an appropriate random access procedure corresponding to the propagation delay between a terminal and a base station can be implemented.

[0017] More advantages and effects of an embodiment of the present disclosure will be explained through the description and drawings. These advantages and / or effects are provided by several embodiments, and the features described in the description and drawings, but not necessarily all of them need to be provided in order to obtain one or more of the same features. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a diagram showing an example of a four-step random access procedure.

[0019] Figure 2 This is a block diagram showing a partial structure of a terminal according to one embodiment.

[0020] Figure 3 This is a block diagram showing a partial structure of a base station according to one embodiment.

[0021] Figure 4 This is a block diagram showing an example of the structure of a terminal according to one embodiment.

[0022] Figure 5 This is a block diagram showing an example of the structure of a base station according to one embodiment.

[0023] Figure 6 This is a diagram showing a first example of a preamble sequence in one embodiment.

[0024] Figure 7 This is a diagram showing a reference example of a preamble sequence.

[0025] Figure 8 This is a diagram showing a second example of a preamble sequence according to one embodiment.

[0026] Fig. 9 This is a diagram showing a third example of a preamble sequence according to one embodiment.

[0027] Fig.10 is a diagram showing the fourth example of a preamble sequence in one embodiment.

[0028] Fig.11 This is a diagram showing an example of the combined use of preamble code sequences.

[0029] Fig.12 The figure shows an example of a CP (cyclic prefix) added to a preamble sequence.

[0030] Description of Reference Numerals

[0031] 100 terminal; 101 PRACH generating unit; 102, 206 data generating unit; 103, 208 wireless transmitting unit; 104, 201 antenna; 105, 202 wireless receiving unit; 106 demodulation / decoding unit; 200 base station; 203 data receiving processing unit; 204 PRACH detecting unit; 205 PRACH resource setting unit; 207 data transmitting processing unit. DETAILED DESCRIPTION

[0032] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0033] [Random access process]

[0034] For example, the random access procedure is implemented through four-step random access (also called "4-step RACH (Random Access Channel)" or "4-Step CBRA (Contention Based Random Access)").

[0035] Figure 1 is a diagram showing an example of a four-step random access process. In the four-step random access, for example, Figure 1 As shown, the terminal (UE) sends the preamble signal of PRACH (Physical Random Access Channel) to the base station (gNB) in the first step of transmission (MSG1). The MSG1 transmission in the terminal is implemented in the transmission timing (slot timing) notified by the base station for each cell.

[0036] The base station receives and decodes MSG1, and in the second step of transmission (MSG2), notifies the terminal of scheduling information including a response (RA response) to the preamble signal and uplink transmission timing of MSG3.

[0037] The terminal receives MSG2 and decodes it. In the third step of sending (MSG3), the terminal uses the scheduling information indicated by MSG2 to notify the base station of information related to the terminal (for example, terminal ID, etc.) and other information used to establish a connection. For example, MSG3 is notified in PUSCH (Physical Uplink Shared Channel). The information notified by MSG3 can also be called "RRC (Radio Resource Control) connection request information".

[0038] The base station receives and decodes MSG3, and in the fourth step (MSG4), notifies a connection establishment response and the like.

[0039] [PRACH]

[0040] For example, the PRACH used in NR (e.g. Figure 1MSG1) is composed of CP (cyclic prefix), preamble sequence (preamble part) and GP (guard period). The preamble sequence is generated, for example, by a code sequence with good correlation characteristics (for example, a cyclic shifted Zadoff-Chu (CS-ZC) sequence). In addition, CP is a signal obtained by copying a part of the preamble sequence. GP is a non-transmitted interval. In addition, the code sequence used for the preamble sequence is not limited to the CS-ZC sequence, as long as it is a code sequence with good correlation characteristics. In addition, a signal that includes CP, preamble sequence and GP and is sent in PRACH is sometimes recorded as a "preamble signal". In addition, the transmission of the preamble signal in PRACH is sometimes recorded as "PRACH transmission".

[0041] Such PRACH-related information is included in the cell information of the base station and is notified to the terminal. For example, for each preamble code number, a different CS-ZC sequence uniquely corresponds. The terminal sets the CS-ZC sequence corresponding to the randomly selected preamble code number as the preamble code sequence. For example, even if multiple terminals use the same time resources and frequency resources to send PRACH, as long as the multiple terminals select different preamble code numbers respectively, the base station can still detect multiple preamble code numbers (in other words, preamble code signals of multiple terminals) at the same time through the correlation detection of the CS-ZC sequence.

[0042] [Expansion to non-terrestrial networks (NTN)]

[0043] In NR, expansion to non-terrestrial networks (NTN: Non-Terrestrial Network) such as communications using satellites and / or high-altitude pseudo-satellites (HAPS: High-altitude platform station) has been studied (for example, Non-Patent Document 1).

[0044] In the NTN environment, the coverage area (e.g., more than one cell) of a satellite for a ground terminal or an aircraft terminal is formed by a beam from the satellite. In addition, the round-trip time of radio wave propagation between the terminal and the satellite depends on the altitude of the satellite (e.g., up to about 36,000 km) and / or the angle from the terminal.

[0045] For example, a satellite forms a cell with a diameter of hundreds of kilometers. The cell formed by a satellite is larger than a cell with a diameter of several kilometers formed by a ground base station, etc. Therefore, depending on the position of a terminal in the cell formed by the satellite, the difference in propagation delay between the terminal and the satellite increases.

[0046] For example, non-patent document 1 records that in NTN, the round trip time (RTT) of radio wave propagation between the satellite and the terminal is about 544ms at most. In addition, non-patent document 1 also records that the maximum delay difference of about 1.6ms will be generated according to the position of the terminal in the beam (in the cell). The maximum delay difference refers to, for example, the difference between the round trip time between the terminal farthest from the satellite and the satellite within the beam (in the cell) and the round trip time between the terminal closest to the satellite and the satellite.

[0047] In a terrestrial cell with a diameter of several kilometers, the maximum delay difference is, for example, less than 0.1 ms. Therefore, the maximum delay difference in the NTN is very large compared with that in the terrestrial cell. Therefore, in the NTN, the delay difference of the preamble signal received by the satellite from the terminal will become larger.

[0048] In a cellular system, interference between cells can be reduced by using a different set of ZC sequences for each cell. For LTE or NR targeting terrestrial cells, CS multiplexing is used within the cell, so the number of CS-ZC sequences used in the cell corresponds to the product of the number of ZC sequences used in each cell and the number of CS multiplexing that can be performed. In this case, the probability (collision probability) that the preamble signal between terminals will collide due to the selection of the same CS-ZC sequence between terminals in the cell is reduced.

[0049] On the other hand, in the NTN environment, the size of the cell is extremely large compared to the ground cell of several kilometers, and the delay difference of the preamble signal is large, so it may not be possible to ensure a sufficient number of cells that can be multiplexed for CS. Therefore, in the NTN environment, in order to achieve a sufficiently low collision probability within the cell, it is possible to consider increasing the number of ZC sequences used in each cell in accordance with the reduction in the number of cells that can be multiplexed for CS. However, for example, because there is a limit on the number of ZC sequences that can be used (for example, a maximum of 838 ZC sequences with a sequence length of 839 can be used), if the number of ZC sequences used in each cell is large, the number of cells to which different ZC sequences can be allocated (reuse factor) will decrease, and the interference with other cells will increase. For example, in the NTN environment, a cell is formed by a beam formed by a satellite, so the signal power difference with other cells depends on the directional characteristics of the satellite beam rather than on the distance attenuation of the radio wave. Therefore, compared with the ground cell, the interference with other cells will become significant.

[0050] Therefore, in the present disclosure, for example, even in a case where the propagation delay between the terminal and the base station varies greatly between terminals such as in an NTN environment, an appropriate random access process corresponding to the propagation delay between the terminal and the base station can be achieved by flexibly setting the structure of the preamble code sequence.

[0051] (One embodiment)

[0052] [Overview of Communication System]

[0053] 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 (equivalent to a transmitting device) transmits a PRACH, and the base station 200 (equivalent to a receiving device) receives the PRACH.

[0054] Figure 2 1 is a block diagram showing a part of the structure of the terminal 100 according to an embodiment of the present disclosure. Figure 2 In the terminal 100 shown, the wireless transmission unit 103 transmits a signal of a random access channel. The control unit 107 sets a preamble sequence for the signal of the random access channel from a plurality of candidate preamble sequences. At least one candidate preamble sequence among the plurality of candidate preamble sequences is composed of two or more code sequences that are different from each other.

[0055] Figure 3 2 is a block diagram showing a part of the structure of the base station 200 according to the embodiment of the present disclosure. Figure 3 In the base station 200 shown, the wireless receiving unit 202 receives the signal of the random access channel. The control unit 209 determines the preamble sequence included in the signal of the random access channel from a plurality of candidate preamble sequences. At least one candidate preamble sequence among the plurality of candidate preamble sequences is composed of two or more code sequences that are different from each other.

[0056] [Terminal structure]

[0057] Figure 4 1 is a block diagram showing an example of the configuration of the terminal 100 according to Embodiment 1. The terminal 100 includes a PRACH generation unit 101, a data generation unit 102, a wireless transmission unit 103, an antenna 104, a wireless reception unit 105, and a demodulation / decoding unit 106. The PRACH generation unit 101, the data generation unit 102, and the demodulation / decoding unit 106 may be included in a control unit 107.

[0058] The PRACH generation unit 101 determines the PRACH transmission resource from the candidate PRACH transmission resources available in the cell of the base station 200, for example. For example, the PRACH generation unit 101 sets the time / frequency resource and preamble number for PRACH transmission based on the time / frequency resource and preamble number group information on which the PRACH can be transmitted. The time / frequency resource and preamble number group information on which the PRACH can be transmitted are notified by the base station 200, for example.

[0059] In addition, the information related to the candidate PRACH transmission resources available to the terminal 100 (PRACH transmission resource information) includes the candidate sequence number (preamble number group) for the preamble, the CS amount, the PRACH time resource (for example, period), the PRACH frequency resource position, the preamble format (Preamble format) number and other setting information associated with PRACH. In addition, the PRACH transmission resource information available to the terminal 100 may include frequency hopping information. The frequency hopping information is information indicating the frequency hopping mode for the sequence number used for the preamble. In other words, the PRACH transmission resource information includes information for generating the preamble signal of the PRACH and information related to the time / frequency resources for transmitting the preamble signal of the PRACH. In addition, the PRACH transmission resource information is included in the control information (RRC message (for example, RACH-ConfigCommon, RACH-ConfigDedicated and RACH-ConfigGeneric, etc.) sent by the connected base station 200 (for example, the serving cell), and is notified to the terminal 100 in the system information. In addition, part of the control information may be not notified to the terminal 100 from the base station 200 as system common information specified by the specification.

[0060] For example, the PRACH generation unit 101 sets a preamble number from the preamble number group. The PRACH generation unit 101 sets the preamble sequence based on the ZC sequence and frequency hopping information corresponding to the set preamble number. Then, the PRACH generation unit 101 generates a PRACH signal (e.g., a preamble signal) to be transmitted in the set time / frequency resource.

[0061] In addition, an example of a preamble code sequence generated based on the ZC sequence and frequency hopping information will be described later.

[0062] In addition, the PRACH generation unit 101 may perform a cyclic shift on the generated preamble sequence using the CS amount.

[0063] The data generating unit 102 generates an uplink transmission data stream and generates a data signal to be transmitted using the time / frequency resources and MCS (Modulation and Coding Scheme) allocated by the base station 200 for transmitting the data signal.

[0064] The wireless transmission unit 103 performs transmission processing such as D / A (Digital / Analog) conversion and up-conversion on the signal output from the PRACH generation unit 101 and the data signal output from the data generation unit 102, and transmits the wireless signal obtained by the transmission processing from the antenna 104 to the base station 200.

[0065] The wireless reception unit 105 performs reception processing such as down-conversion and A / D (Analog / Digital) conversion on the reception signal received from the base station 200 via the antenna 104 , and outputs the reception-processed signal to the demodulation / decoding unit 106 .

[0066] The demodulation / decoding unit 106 demodulates and decodes the signal output from the wireless receiving unit 105. For example, the demodulation / decoding unit 106 demodulates and decodes the response data signal of the PRACH. For example, when the information obtained by demodulation and decoding includes frequency hopping information, the demodulation / decoding unit 106 outputs the frequency hopping information to the PRACH generating unit 101.

[0067] [Structure of base station]

[0068] Figure 5 2 is a block diagram showing an example of the configuration of the base station 200 according to the present embodiment. The base station 200 includes an antenna 201, a wireless receiving unit 202, a data receiving processing unit 203, a PRACH detecting unit 204, a PRACH resource setting unit 205, a data generating unit 206, a data transmission processing unit 207, and a wireless transmitting unit 208. The data receiving processing unit 203, the PRACH detecting unit 204, the PRACH resource setting unit 205, the data generating unit 206, and the data transmission processing unit 207 may be included in the control unit 209.

[0069] The wireless reception unit 202 performs reception processing such as down-conversion and A / D conversion on the data signal and PRACH signal received from the terminal 100 via the antenna 201 , and outputs the reception processed signals to the data reception processing unit 203 and the PRACH detection unit 204 .

[0070] The PRACH resource setting unit 205 sets the time / frequency resources and preamble numbers that can be used for PRACH transmission in the cell to the PRACH detection unit 204. In addition, the PRACH resource setting unit 205 outputs system information (e.g., random access configuration and RACH-Config, etc.) including the time / frequency resources and preamble numbers that can be used for PRACH transmission in the cell to the data generation unit 206. Here, the time / frequency resources that can be used for PRACH transmission are sometimes referred to as "RACH Occasion".

[0071] In addition, the information that the PRACH resource setting unit 205 sets to the PRACH detection unit 204 may include frequency hopping information. In addition, the system information that the PRACH resource setting unit 205 outputs to the data generation unit 206 may include frequency hopping information. In addition, the frequency hopping information may be set for each cell.

[0072] The PRACH detection unit 204 performs correlation processing on the received PRACH preamble signal and the replica signal of the preamble signal, thereby detecting the PRACH preamble signal and estimating the sending timing and receiving timing. The replica signal of the preamble signal is a signal generated using the ZC sequence and frequency hopping information corresponding to the preamble number set by the PRACH resource setting unit 205.

[0073] In addition, the correlation processing in the PRACH detection unit 204 can be a process of calculating the delay distribution in the time domain, or a process of calculating the delay distribution by performing IFFT (Inverse Fast Fourier Transform) after performing correlation processing (division processing) in the frequency domain. The calculated delay distribution can be used for estimating the transmission timing and / or reception timing.

[0074] The data reception processing unit 203 performs demodulation / decoding processing on the received data signal. In addition, the data reception processing unit 203 can perform channel estimation and timing estimation based on the received data signal.

[0075] The data generation unit 206 generates a downlink data signal including user data, system information, dedicated control information, etc. The data generation unit 206 outputs the generated downlink data signal to the data transmission processing unit 207 .

[0076] The data transmission processing unit 207 encodes and modulates the downlink data signal output from the data generation unit 206 , and outputs the modulated signal to the wireless transmission unit 208 .

[0077] The wireless transmission unit 208 performs transmission processing such as D / A conversion, up-conversion, and amplification on the signal output from the data transmission processing unit 207 , and transmits a wireless signal obtained by the transmission processing from the antenna 201 .

[0078] Next, the preamble sequence in this embodiment is described. In addition, an example of a preamble sequence having four ZC sequences is described below. A preamble sequence having four ZC sequences can be regarded as a preamble sequence formed by connecting four ZC sequences (or a preamble sequence having a connection number of 4). In addition, the following describes the preamble sequence that can be used by each cell (in other words, the candidate preamble sequence) for the case where the number of preamble sequences that can be used by each cell is 64 and two cells are used.

[0079] [First example of a preamble sequence]

[0080] Figure 6 : is a diagram showing a first example of a preamble sequence according to this embodiment. Figure 6 The figure shows the preamble sequences that can be used by two cells (cell 0 and cell 1). In addition, the preamble sequences that can be used by each cell are 64 preamble sequences, namely preamble 0 to preamble 63. Preamble 0 to preamble 63 have identification numbers (preamble numbers) of the preamble sequences, namely preamble numbers 0 to 63. In addition, Figure 6 The Seq.i shown in FIG. 1 represents a ZC sequence, and i represents the sequence number of the ZC sequence. Figure 6 In the example of , i takes a value of an integer from 0 to 63. In addition, the cell identification number (cell ID (Identification)) of cell 0 is 0, and the cell ID of cell 1 is 1.

[0081] exist Figure 6 In the example, the ZC sequence shown in the left column is sometimes described as a "base sequence" (or "root sequence"). In addition, the ZC sequences connected to the base sequence are sometimes described as "concatenated sequence #1", "concatenated sequence #2", and "concatenated sequence #3" in sequence.

[0082] exist Figure 6 In the example of , a common set of basic sequences between cells is set, and different offsets are set for each cell. Figure 6 In , the set of 64 ZC sequences Seq.0 to Seq.63 is the set of basic sequences common to cell 0 and cell 1. Figure 6 In the example, the offset of cell 0 is 4 and the offset of cell 1 is 7.

[0083] like Figure 6As shown, in the first example, the usable preamble sequences (candidate preamble sequences) include preamble sequences having code sequences different from each other.

[0084] Figure 6 For example, the base sequence of preamble 0 of cell 0 is Seq.0. With respect to base sequence Seq.0, Seq.4 having sequence number 4 obtained by adding the sequence number of Seq.0 to the offset of cell 0, i.e., 4, is set as concatenated sequence #1. Seq.8 having sequence number 8 obtained by adding the sequence number of Seq.4 to 4 is set as concatenated sequence #2. Seq.12 having sequence number 12 obtained by adding the sequence number of Seq.8 to 4 is set as concatenated sequence #3. For preamble 1 to preamble 63 of cell 0, concatenated sequence #1 to concatenated sequence #3 are set based on the base sequence and the offset in the same manner as preamble 0 of cell 0.

[0085] Figure 6 For example, the base sequence of preamble 0 of cell 1 is the same as preamble 0 of cell 0, which is Seq.0. The sequence number of Seq.0 is sequentially added with the offset of cell 1, that is, 7, so that Seq.7, Seq.14, and Seq.21 are set as concatenation sequence #1, concatenation sequence #2, and concatenation sequence #3, respectively. For preamble 1 to preamble 63 of cell 1, concatenation sequence #1 to concatenation sequence #3 are set based on the base sequence and the offset, similarly to preamble 0 of cell 1.

[0086] In addition, the Mod operation can be used to add an offset. For example, Figure 6 In the example of , a sequence number not exceeding the number of usable ZC sequences is calculated by using a Mod64 operation corresponding to the number of usable preamble sequences (usable ZC sequences) of 64. Figure 6 The preamble 63 of Seq. 63 is added with the offset of cell 0, ie, 4, to the sequence number of Seq. 63 relative to the base sequence of Seq. 63. Next, Seq. 3 having the sequence number 3 calculated by operation using Mod64 (for example, (63+4)Mod64=3) is set as concatenated sequence #1.

[0087] exist Figure 6 In the example shown, a set of common basic sequences between cell 0 and cell 1 is set, and different offsets are set between cell 0 and cell 1. According to this setting, a base station receiving a preamble signal can identify the preamble sequence within a cell and between cells. In addition, according to this setting, the reuse factor of the sequence number of the ZC sequence can be increased. In addition, the base station can perform synthesis and receive a preamble signal including a preamble sequence formed by connecting multiple ZC sequences. Therefore, for example, long-distance wireless communication in an NTN environment (for example, a satellite communication environment) can be performed.

[0088] In addition, Figure 6 In the example of , the example of different offsets between cells is 4 or 7, but as long as the offsets are different between cells, they are not limited to 4 or 7. For example, the offset can be greater than 1. In addition, the offset can also be the number of ZC sequences contained in the preamble sequence (in Figure 6 In the example, it is 4) or above.

[0089] In addition, the offset in the first example may be equivalent to an example of a frequency hopping pattern represented by the frequency hopping information. For example, the frequency hopping pattern may be a pattern that sequentially specifies an offset for setting the concatenation sequence #1 from the base sequence, an offset for setting the concatenation sequence #2 from the concatenation sequence #1, and an offset for setting the concatenation sequence #3 from the concatenation sequence #2. For example, it can be understood that, Figure 6 The frequency hopping pattern of cell 0 is {4, 4, 4}, Figure 6 The frequency hopping pattern of cell 1 is {7, 7, 7}. In addition, the frequency hopping information may indicate one offset or a frequency hopping pattern including multiple offsets.

[0090] For example, the PRACH generation unit 101 of the terminal 100 in the cell 0 selects the preamble code number group ( Figure 6 A preamble code number is set in the range of 0 to 63 in the PRACH generator 101. The PRACH generator 101 generates a preamble code based on the ZC sequence and frequency hopping information ( Figure 6 The preamble sequence is generated by using the offset 4 in the PRACH generator 101. Here, the ZC sequence corresponding to the preamble number set by the PRACH generator 101 corresponds to the base sequence. For example, the PRACH generator 101 sets each concatenated sequence based on the base sequence and the frequency hopping information, and concatenates the base sequence with the concatenated sequence to generate the preamble sequence.

[0091] For example, the PRACH detection unit 204 of the base station 200 also sets each concatenated sequence based on the base sequence and the frequency hopping information, and concatenates the base sequence and the concatenated sequence to generate a preamble sequence, similarly to the PRACH generation unit 101. The PRACH detection unit 204 generates a preamble sequence that can be used in the cell, and generates a replica signal of the preamble signal including the preamble sequence.

[0092] [Second example of preamble sequence]

[0093] Figure 7 This is a diagram showing a reference example of a preamble sequence. Figure 7 64 preamble sequences (preamble 0 to preamble 63) are shown in the case where the offset is set to 1 in the first example.

[0094] exist Figure 7 For example, in the preamble 1 Figure 7 If the ZC sequence is shifted to the right by one, the shifted Seq.1, Seq.2, and Seq.3 of preamble 1 will partially overlap with Seq.1, Seq.2, and Seq.3 of preamble 0. Figure 7 The shift in the right direction (or left direction) in , for example, corresponds to the shift (e.g., delay) of the preamble signal including the preamble sequence in the time domain. Therefore, for example, when the preamble signal including the preamble 1 is shifted by one ZC sequence in the time domain, the base station receiving the preamble signal will have difficulty distinguishing the preamble 1 from the preamble 2.

[0095] In the second example, an example of a preamble sequence will be described in which, even when one preamble sequence is shifted in the time domain, a ZC sequence included in the one preamble sequence does not overlap with (does not continuously be the same as) a ZC sequence of another preamble sequence.

[0096] Figure 8 It is a diagram showing a second example of the preamble sequence according to the present embodiment. Figure 8 In, with Figure 6 Similarly, preamble sequences that can be used by two cells (cell 0 and cell 1) are shown.

[0097] exist Figure 8 In the example of , a set of common base sequences between cells is set, and different offsets are set for each cell. Moreover, the offsets are set to different values ​​between adjacent ZC sequences. Sometimes, the offset used to set the concatenated sequence #1 from the base sequence is recorded as "first offset", the offset used to set the concatenated sequence #2 from the concatenated sequence #1 is recorded as "second offset", and the offset used to set the concatenated sequence #3 from the concatenated sequence #2 is recorded as "third offset".

[0098] The offset in the second example can be set based on the order of the cell identification number and the offset. The jth offset N1 in the case of a cell identification number of k can be set to N1 = {k × (J-1)} + j. Here, J is the number of ZC sequences contained in the preamble sequence. For example, in Figure 8 , J is 4.

[0099] For example, in Figure 8 In cell 0, the first offset is 1, the second offset is 2, and the third offset is 3. Figure 8 In cell 1, the first offset is 4, the second offset is 5, and the third offset is 6. Moreover, in Figure 8 In the example, concatenated sequence #1 to concatenated sequence #3 are set based on the base sequence and each offset.

[0100] like Figure 8As shown, in the second example, the usable preamble sequences (candidate preamble sequences) include preamble sequences having code sequences different from each other.

[0101] In addition, the offset setting and the offset addition operation can use Mod operation. Figure 8 In the example of , by using the Mod64 operation corresponding to the number of usable preamble code sequences (usable ZC sequences) 64, the sequence number that does not exceed the number of usable ZC sequences is calculated.

[0102] The preamble sequence is set based on the above offset, thereby, even if a preamble sequence is shifted in the time domain, it is possible to avoid the ZC sequence contained in the preamble sequence from overlapping with the ZC sequence of other preamble sequences. Therefore, for example, even in the case where the delay difference between terminals such as an NTN environment (e.g., a satellite communication environment) is relatively large, the part (overlapping part) of the preamble sequence contained in the delayed preamble signal that is the same as the preamble sequence of the preamble signal of the other terminal can be reduced, thereby reducing interference between terminals in the cell and interference between cells.

[0103] In addition, the offset in the second example may be equivalent to an example of a frequency hopping pattern represented by the frequency hopping information. For example, the frequency hopping pattern may be a pattern that specifies the first offset, the second offset, and the third offset in sequence. For example, it can be understood that, Figure 8 The frequency hopping pattern of cell 0 is {1, 2, 3}, Figure 8 The frequency hopping pattern of cell 1 is {4, 5, 6}. In addition, the frequency hopping information may indicate one offset or a frequency hopping pattern including a plurality of offsets. In addition, in the second example, the offset is set according to the order of the cell identification number and the offset. Therefore, for example, when the terminal 100 has information indicating the cell identification number and information indicating the order of the offset (for example, information indicating the number of connections of the preamble sequence, the format of the preamble sequence, etc.), the terminal 100 may calculate the offset according to the order of the cell identification number and the offset. In this case, the frequency hopping information may not be notified to the terminal 100.

[0104] [Third example of preamble sequence]

[0105] In the first example and the second example, an example is shown in which the method for setting the preamble sequence from the base sequence is common to each preamble sequence in the preamble sequence that can be used in a cell. The present disclosure is not limited thereto. In the third example, an example is described in which the method for setting the preamble sequence from the base sequence is different for each preamble sequence that can be used in a cell.

[0106] Fig. 9 It is a diagram showing a third example of the preamble sequence according to the present embodiment. Fig. 9 In, with Figure 6 and Figure 8 Similarly, preamble sequences that can be used by two cells (cell 0 and cell 1) are shown.

[0107] exist Fig. 9 In the example of , a set of common base sequences is set between cells. Furthermore, the offset of the preamble sequence (for example, concatenation sequence #1 to concatenation sequence #3) is set differently for each preamble sequence from the base sequence.

[0108] The offset in the third example may be set based on the cell identification number and the preamble number. For example, when the cell identification number is k, the offset N2 for setting the preamble sequence with the preamble number m may be set to N2=k+m.

[0109] For example, in Fig. 9 In cell 0 of , the offset of the preamble sequence (preamble 0) with preamble number 0 is set to 0, and the offset of the preamble sequence (preamble 1) with preamble number 1 is set to 1. In addition, for example, in Fig. 9 In cell 1, the offset of the preamble sequence (preamble 0) with preamble number 0 is set to 1, and the offset of the preamble sequence (preamble 1) with preamble number 1 is set to 2. Fig. 9 In the example, concatenated sequence #1 to concatenated sequence #3 are set based on the base sequence and each offset.

[0110] like Fig. 9 As shown, in the third example, the usable preamble sequences (candidate preamble sequences) include preamble sequences having code sequences different from each other.

[0111] In addition, the Mod operation can be used to set the offset and add the offset. Fig. 9 In the example of , by using the Mod64 operation corresponding to the number of usable preamble code sequences (usable ZC sequences) 64, the sequence number that does not exceed the number of usable ZC sequences is calculated.

[0112] The preamble sequence is set based on the above offset, thereby, even if a preamble sequence is shifted in the time domain, it is possible to avoid the ZC sequence contained in the preamble sequence from overlapping with the ZC sequence of other preamble sequences. Therefore, for example, even in the case where the delay difference between terminals such as an NTN environment (e.g., a satellite communication environment) is relatively large, the part (overlapping part) of the preamble sequence contained in the delayed preamble signal that is the same as the preamble sequence of the preamble signal of the other terminal can be reduced, thereby reducing interference between terminals in the cell and interference between cells.

[0113] In addition, the offset in the third example may be equivalent to an example of a frequency hopping pattern. For example, the frequency hopping pattern may be a pattern that sequentially specifies a first offset, a second offset, and a third offset. For example, it may be understood that, Fig. 9 The frequency hopping pattern of the preamble code 0 of the cell 0 is {0, 0, 0}. In addition, for example, it can be understood that, Fig. 9 The frequency hopping pattern of the preamble code 0 of the cell 1 is {1, 1, 1}. In addition, the frequency hopping information may represent one offset or a frequency hopping pattern including multiple offsets according to the preamble code number. In addition, in the third example, the offset is set according to the cell identification number and the preamble code number. In addition, the terminal 100 sets a preamble code number from the preamble code number group. Therefore, for example, in the case where the terminal 100 has information indicating the cell identification number, the terminal 100 may calculate the offset according to the cell identification number and the preamble code number. In this case, the frequency hopping information may not be notified to the terminal 100.

[0114] [Fourth example of preamble sequence]

[0115] Fig.10 It is a diagram showing a fourth example of the preamble sequence according to the present embodiment. Fig.10 In, with Figure 6 , Figure 8 and Fig. 9 Similarly, preamble sequences that can be used by two cells (cell 0 and cell 1) are shown.

[0116] also, Fig.10 The preamble sequence that can be used in cell 0 is equivalent to Figure 8 The preamble code sequence that can be used in cell 0 is shown.

[0117] Fig.10 The preamble code sequence that can be used in cell 1 is equivalent to the sequence after the preamble code sequence that can be used in cell 0 is cyclically shifted by two ZC sequences.

[0118] like Fig.10As shown, in the fourth example, usable preamble sequences (candidate preamble sequences) include preamble sequences having code sequences different from each other.

[0119] For example, Fig.10 Preamble 0 in cell 1 is equivalent to a sequence obtained by cyclically shifting preamble 1 in cell 0 by two ZC sequences. Preamble 0 to preamble 63 are also cyclically shifted in the same manner as preamble 0.

[0120] According to the setting of the preamble sequence, by making the second cell (for example, Fig.10 0) to set the first cell (for example, Fig.10 The preamble code sequence of cell 1) can be used to increase the reuse factor of the ZC sequence. In addition, when the delay difference between terminals in different cells is less than the specified difference (for example, the delay difference equivalent to two ZC sequences), the interference between cells can be reduced.

[0121] Here, when the preamble sequence of the first cell is set based on the preamble sequence of the second cell, the second cell may be referred to as the "reference cell" of the first cell. In this case, the frequency hopping information in the fourth example may include the frequency hopping information of the reference cell and information indicating the cyclic shift amount relative to the preamble sequence of the reference cell. In other words, Fig.10 In the case of, for example, in the frequency hopping information, for cell 1, information related to the setting of the preamble sequence that can be used in cell 0 (first information) and information indicating the cyclic shift amount for setting the preamble sequence that can be used in cell 1 from the preamble sequence that can be used in cell 0 (second information) can be included. In this case, the PRACH generation unit 101 of the terminal 100 of cell 1 generates a preamble sequence from the preamble sequence that can be used in cell 0 based on the first information. Then, the terminal 100 of cell 1 cyclically shifts the generated preamble sequence based on the second information, thereby generating a preamble sequence used by cell 1.

[0122] In addition, Fig.10 The example of cyclic shifting two ZC sequences (the cyclic shift amount is an example of an amount equivalent to two ZC sequences) is shown in the example, but the present disclosure is not limited to this. The amount of cyclic shift may also be an amount equivalent to one ZC sequence, or an amount equivalent to three or more ZC sequences. For example, when the amount of cyclic shift is an amount equivalent to one ZC sequence, as long as the delay difference between cells is less than the delay difference equivalent to one ZC sequence, the interference between cells can be reduced.

[0123] In addition, Fig.10 In the example, it is shown that the preamble sequence that can be used in cell 0 is equivalent to Figure 8The example of the preamble sequence that can be used by cell 0 is shown in FIG. 1 , but the present disclosure is not limited thereto. The method of setting the preamble sequence that can be used by the reference cell may also be the method of setting shown in the other examples (eg, the first example or the third example) described above.

[0124] In the present embodiment described above, the terminal 100 sets the preamble sequence for PRACH transmission from the available preamble sequences (candidate preamble sequences). Moreover, in the present embodiment, the candidate preamble sequences include preamble sequences having two or more code sequences that are different from each other. According to this setting, even in the case where the propagation delay between the terminal and the base station is greatly different between the terminals such as in the NTN environment, by flexibly setting the structure of the preamble sequence, an appropriate random access process corresponding to the propagation delay between the terminal and the base station can be implemented.

[0125] According to this setting, a base station receiving a preamble signal can identify a preamble sequence within a cell and between cells. In addition, according to this setting, the reuse factor of the sequence number of the ZC sequence can be increased. In addition, the base station can synthesize and receive a preamble signal including a preamble sequence formed by concatenating multiple ZC sequences. Therefore, for example, long-distance wireless communication in an NTN environment (e.g., a satellite communication environment) can be performed.

[0126] In addition, the first to fourth examples of the above-mentioned implementation methods can be used in combination or can be switched dynamically. For example, the base station 200 can also select a setting method (generation method) of a preamble sequence shown in the first to fourth examples for the terminal 100. In this case, information indicating the selected setting method can be notified to the terminal 100. For example, the information indicating the selected setting method can be included in the frequency hopping information, or other signaling (for example, high-layer signaling and DCI, etc.) can be used to notify the information.

[0127] In addition, in the above-mentioned embodiment, the cell can be an area defined by the receiving power of SSB (Synchronization Signal / Physical Broadcast Channel Block, PBCHBlock) and / or CSI-RS (Channel State Information-Reference Signal) sent by the base station (satellite), or it can be an area defined by a geographical location.

[0128] In the RRC signaling, the setting of the PRACH resource sent by the base station can be notified by parameter sets such as RACH-ConfigCommon, RACH-ConfigDedicated and RACH-ConfigGeneric. For example, the sequence hopping information in the above implementation mode can also be notified in the above RRC signaling. In addition, the sequence hopping information in the above implementation mode can be broadcast in the system information or notified in the terminal-specific information.

[0129] In addition, in the above-mentioned embodiment, an example of generating a preamble sequence by connecting four ZC sequences is shown, but the present disclosure is not limited to this. The number of connections of the ZC sequence in the preamble sequence can be less than 3 or more than 5. In addition, the number of connections of the ZC sequence in the preamble sequence can also be variable according to the cell. For example, in a cell located close to a satellite (base station), the number of connections of the ZC sequence in the preamble sequence can be relatively reduced, and in a cell located far from the satellite, the number of connections of the ZC sequence in the preamble sequence can be relatively increased. By changing the number of connections according to the cell, the necessary and sufficient PRACH resources can be set. In addition, the preamble signal of the PRACH between cells can be identified based on the number of connections changed according to the cell.

[0130] In addition, in the above-mentioned embodiment, an example of using a ZC sequence in a preamble sequence is shown, but the present disclosure is not limited thereto. For example, other code sequences different from the ZC sequence may also be used for the preamble sequence. For example, a frequency-hopped sequence used by NB-IoT (Narrowband Internet of Things) may also be used for the preamble sequence.

[0131] In addition, in the above embodiment, an example is shown in which the number of preamble sequences that can be used in each cell is 64, but the present disclosure is not limited thereto. The number of preamble sequences that can be used in each cell may be a number other than 64.

[0132] Furthermore, in the above-mentioned embodiment, the preamble sequences in two cells are exemplified, but the present disclosure can be used for setting the preamble sequences in three or more cells.

[0133] In addition, in the above-mentioned embodiment, an example of generating a usable preamble sequence by concatenating ZC sequences, in other words, an example of generating a candidate preamble sequence by concatenating ZC sequences is shown, but the present disclosure is not limited to this. It is also possible to use a preamble sequence generated by concatenating ZC sequences and a preamble sequence generated by repeating a ZC sequence. For example, the use of a preamble sequence generated by concatenating ZC sequences and the use of a preamble sequence generated by repeating a ZC sequence can be set in units of RACH opportunities.

[0134] Fig.11 This is a diagram showing an example of the combined use of preamble code sequences. Fig.11 The horizontal axis represents the time axis. Fig.11 , an example of a preamble signal of a PRACH transmitted in two RACH opportunities (RACH opportunity #1 and RACH opportunity #2) set in the time domain is shown.

[0135] exist Fig.11 In the example, the preamble signal transmitted in RACH opportunity #1 starting from time slot 3 includes a preamble sequence generated by repeating Seq.0 and a CP obtained by copying the last part of Seq.0. In addition, the preamble signal transmitted in RACH opportunity #2 starting from time slot 8 includes a preamble sequence generated by concatenating a plurality of ZC sequences including Seq.0, Seq.1, Seq.2, and Seq.7, and a CP obtained by copying the last part of Seq.7.

[0136] like Fig.11 As shown, by using a preamble sequence generated by concatenating ZC sequences and a preamble sequence generated by repeating one ZC sequence in combination, it is possible to cope with longer distance communication, for example.

[0137] In addition, the concatenation of ZC sequences in this embodiment is not limited to the concatenation of ZC sequences having different sequence numbers, and may also include the concatenation of ZC sequences having the same sequence number. In other words, the preamble sequence generated by concatenating ZC sequences in this embodiment may include a preamble sequence generated by repeating one ZC sequence.

[0138] In addition, for example, in Fig.11 , a CP of a portion of the last part of a preamble sequence having multiple ZC sequences is copied and attached to the front end of the preamble sequence, but the present disclosure is not limited thereto. For example, a CP may be attached to each of the multiple ZC sequences included in the preamble sequence.

[0139] Fig.12 This is a diagram showing an example of a CP added to a preamble sequence. Fig.12 , two options (Option 1 and Option 2) related to the CP added to the preamble sequence are shown.

[0140] exist Fig.12 In Option 1, a CP obtained by copying a portion of the last ZC sequence in the ZC sequence included in the preamble sequence is attached to the front end of the preamble sequence. For example, in the example of Option 1-1, a CP obtained by copying a portion of the last Seq.7 is attached to the front end of the preamble sequence, and in the example of Option 1-2, a CP obtained by copying a portion of the last Seq.9 is attached to the front end of the preamble sequence.

[0141] exist Fig.12 In Option 2, a CP is attached to each ZC sequence contained in the preamble sequence. For example, in the example of Option 2-1, a portion of the CP of the last part of Seq.0 contained in the preamble sequence is copied and attached to the front end of Seq.0. For other ZC sequences (for example, Seq.1, Seq.2, Seq.7, and the ZC sequence between Seq.2 and Seq.7), as with Seq.0, a portion of the CP of the last part of each ZC sequence is copied and attached to the front end of each corresponding ZC sequence. The example of Option 2-2 is also similar to Option 2-1, in that a portion of the CP of the last part of each ZC sequence is copied and attached to the front end of each corresponding ZC sequence.

[0142] Furthermore, it can also be understood that, in Option 2, the CP added to the ZC sequence other than the leading ZC sequence is inserted between ZC sequences.

[0143] When a plurality of ZC sequences are transmitted, they may be transmitted continuously or at intervals.

[0144] In addition, in the above embodiments, an NTN environment (e.g., a satellite communication environment) is used as an example for description, but the present disclosure is not limited thereto. The present disclosure may also be applied to other communication environments (e.g., a terrestrial cellular environment of LTE and / or NR).

[0145] In addition, for example, CS multiplexing and / or multiplexing using a Walsh-Hadamard sequence may be applied to the preamble sequence in the above-mentioned embodiment.

[0146] In addition, expressions such as "...part" in the above embodiments may also be replaced by other expressions such as "...circuitry", "...device", "...unit" or "...module".

[0147] In addition, the term "connect" in the above-mentioned embodiments may be replaced with other terms such as "combine", "arrange (sequentially)", "arrange (sequentially)", etc.

[0148] The present disclosure can be implemented by software, hardware or software in cooperation with hardware. Each functional block used in the description of the above-mentioned embodiment is partially or entirely implemented as an LSI (Large Scale Integration) as an integrated circuit, and each process described in the above-mentioned embodiment can also be partially or entirely controlled by an LSI or a combination of LSIs. LSI can be composed of individual chips, or it can be composed of a chip in a manner that includes part or all of the functional blocks. LSI can also include the input and output of data. LSI can also be called "IC (Integrated Circuit)", "System LSI (System LSI)", "Super LSI (Super LSI)", "Ultra LSI (Ultra LSI)" according to the different integration levels. The method of integrated circuitization is not limited to LSI, and can also be implemented by a dedicated circuit, a general-purpose processor or a dedicated processor. In addition, an FPGA (Field Programmable Gate Array) that can be programmed after LSI manufacturing, or a reconfigurable processor (Reconfigurable Processor) that can reconfigure the connection or setting of the circuit block inside the LSI can also be used. The present disclosure can also be implemented as digital processing or analog processing. Furthermore, if integrated circuit technology that replaces LSI emerges as semiconductor technology advances or other technologies are derived, it is of course possible to use this technology to achieve integration of functional blocks. There is also the possibility of applying biotechnology, etc.

[0149] The present disclosure may be implemented in all kinds of devices, equipment, and systems (collectively referred to as "communication devices") having communication functions. Non-limiting examples of communication devices include phones (mobile phones, smart phones, etc.), tablet computers, personal computers (PCs) (laptops, desktops, notebook computers, etc.), cameras (digital cameras, digital video cameras, etc.), digital players (digital audio / video players, etc.), wearable devices (wearable cameras, smart watches, tracking devices, etc.), game consoles, e-book readers, telehealth / telemedicine (telehealth / prescription) devices, vehicles or transportation vehicles with communication functions (cars, airplanes, ships, etc.), and combinations of the above devices.

[0150] Communication devices are not limited to portable or mobile devices, but also include all kinds of devices, equipment, and systems that cannot be carried or fixed. For example, they include: smart home devices (home appliances, lighting equipment, smart meters or meters, control panels, etc.), vending machines, and all other "things" that can exist on the IoT (Internet of Things) network.

[0151] The communication includes data communication performed by a cellular system, a wireless LAN (Local Area Network) system, a communication satellite system, etc., and also includes data communication performed by a combination of these systems.

[0152] In addition, the communication device also includes devices such as a controller or a sensor connected or linked to the communication device that performs the communication function described in the present disclosure. For example, it includes a controller or a sensor that generates a control signal or a data signal used by the communication device that performs the communication function of the communication device.

[0153] In addition, the communication device includes infrastructure equipment that communicates with the above-mentioned non-limiting various devices or controls the above-mentioned various devices, such as base stations, access points, and all other devices, equipment, and systems.

[0154] A transmitting device according to an embodiment of the present disclosure includes: a transmitting circuit for transmitting a signal of a random access channel; and a control circuit for setting a preamble code sequence for the signal from a plurality of candidate preamble code sequences, wherein at least one of the plurality of candidate preamble code sequences is composed of two or more code sequences that are different from each other.

[0155] In the transmitting device of one embodiment of the present disclosure, the control circuit sets the preamble code sequence based on a sequence number indicating a first code sequence and a frequency hopping pattern for the sequence number.

[0156] In a transmitting device of one embodiment of the present disclosure, the multiple candidate preamble code sequences include a preamble code sequence formed by concatenating a first code sequence and a second code sequence, the second code sequence is a sequence obtained from the first code sequence by a prescribed method, the set of the first code sequences allocated to multiple cells is common among the cells, and the prescribed method is different among the cells.

[0157] In a sending device of one embodiment of the present disclosure, the second code sequence has a sequence number, and the sequence number depends on the sequence number of the first code sequence, the identifier of the cell, and the position of the second code sequence, and the position of the second code sequence is the position calculated from the first code sequence in the preamble code sequences included in the multiple candidate preamble code sequences.

[0158] In a transmitting device of one embodiment of the present disclosure, the preamble code sequence contained in the multiple candidate preamble code sequences includes the first code sequence and M (M is an integer greater than 1) second code sequences sequentially connected to the first code sequence, and the mth (m is an integer greater than 1 and less than M) connected second code sequence has a sequence number obtained by adding m×N (N is an integer greater than 1) to the sequence number of the first code sequence, and N is different between the cells.

[0159] In a transmitting device according to an embodiment of the present disclosure, N has a value that depends on an identifier of the cell and a sequence number of the first code sequence.

[0160] In a transmitting device of one embodiment of the present disclosure, the preamble code sequence contained in the multiple candidate preamble code sequences has the first code sequence and M (M is an integer greater than 1) second code sequences sequentially connected to the first code sequence, the first connected second code sequence has a sequence number obtained by adding N to the sequence number of the first code sequence, the m-th (m is an integer greater than 2 and less than M) connected second code sequence has a sequence number obtained by adding N to the sequence number of the m-1-th connected second code sequence, and N has a value that depends on the identifier of the cell and the connection bit order of the second code sequence.

[0161] In a sending device of one embodiment of the present disclosure, the second preamble code sequence will not overlap with any of the multiple candidate preamble code sequences in units of code sequences, and the second preamble code sequence is a sequence that shifts the first preamble code sequence contained in the multiple candidate preamble code sequences in units of code sequences.

[0162] In a transmitting device of an embodiment of the present disclosure, the first preamble code sequence included in the multiple candidate preamble code sequences in the first cell is a preamble code sequence that cyclically shifts the second preamble code sequence included in the multiple candidate preamble code sequences in the second cell in units of code sequences.

[0163] A receiving device of an embodiment of the present disclosure includes: a receiving circuit, which receives a signal of a random access channel; and a control circuit, which determines a preamble code sequence contained in the signal from a plurality of candidate preamble code sequences, wherein at least one candidate preamble code sequence among the plurality of candidate preamble code sequences is composed of two or more code sequences that are different from each other.

[0164] In a sending method of one embodiment of the present disclosure, a preamble code sequence for a signal of a random access channel is set from a plurality of candidate preamble code sequences; and the signal of the random access channel is sent, wherein at least one candidate preamble code sequence among the plurality of candidate preamble code sequences is composed of two or more code sequences that are different from each other.

[0165] In a receiving method of one embodiment of the present disclosure, a signal of a random access channel is received; and a preamble code sequence contained in the signal is determined from multiple candidate preamble code sequences, at least one candidate preamble code sequence among the multiple candidate preamble code sequences is composed of more than two code sequences that are different from each other.

[0166] The disclosures of the specification, drawings, and abstract contained in Japanese patent application No. 2019-064605 filed on March 28, 2019 are incorporated herein by reference in their entirety.

[0167] Industrial Applicability

[0168] One embodiment of the present disclosure is useful for a wireless communication system.

Claims

1. A sending device, comprising: A transmitting circuit for transmitting a signal of a random access channel; and The control circuit sets a preamble sequence for the signal from a plurality of candidate preamble sequences, The preamble sequence is sent at least on the first random access channel, i.e., the first RACH timing and the second RACH timing, The number of ZC (Zadoff-Chu) sequences included in the preamble sequence varies for each cell.

2. The transmitting device according to claim 1, wherein: The preamble code sequence is generated by repeating a code sequence.

3. The transmitting device according to claim 1, wherein: At least one candidate preamble code sequence among the plurality of candidate preamble code sequences is composed of two or more code sequences that are different from each other.

4. The transmitting device according to claim 3, wherein: The control circuit sets the preamble sequence based on a sequence number indicating a first code sequence and a frequency hopping pattern for the sequence number.

5. The transmitting device according to claim 3, wherein: The plurality of candidate preamble sequences include a preamble sequence obtained by concatenating a first code sequence and a second code sequence, wherein the second code sequence is a sequence obtained from the first code sequence by a predetermined method, The set of the first code sequences allocated to the plurality of cells is common among the cells, The provision method differs between the cells.

6. The transmitting device according to claim 5, wherein: The second code sequence has a sequence number, and the sequence number depends on the sequence number of the first code sequence, the identifier of the cell, and the position of the second code sequence, and the position of the second code sequence is a position counted from the first code sequence in the preamble code sequences included in the multiple candidate preamble code sequences.

7. The transmitting device according to claim 6, wherein: The preamble code sequence included in the plurality of candidate preamble code sequences includes the first code sequence and M second code sequences sequentially connected to the first code sequence, where M is an integer greater than 1, The m-th concatenated second code sequence has a sequence number obtained by adding m×N to the sequence number of the first code sequence, where m is an integer greater than or equal to 1 and less than or equal to M, and N is an integer greater than or equal to 1. N differs between the cells.

8. The transmitting device according to claim 7, wherein: N has a value that depends on an identifier of the cell and a sequence number of the first code sequence.

9. The transmitting device according to claim 6, wherein: The preamble code sequence included in the plurality of candidate preamble code sequences includes the first code sequence and M second code sequences sequentially connected to the first code sequence, where M is an integer greater than 1, The first concatenated second code sequence has a sequence number obtained by adding N to the sequence number of the first code sequence, The m-th concatenated second code sequence has a sequence number obtained by adding N to the sequence number of the m-1-th concatenated second code sequence, where m is an integer greater than or equal to 2 and less than or equal to M. N has a value that depends on the identifier of the cell and the concatenation bit order of the second code sequence.

10. The transmitting device according to claim 3, wherein: The second preamble sequence does not overlap with any of the plurality of candidate preamble sequences in units of code sequences, and the second preamble sequence is a sequence obtained by shifting the first preamble sequence included in the plurality of candidate preamble sequences in units of code sequences.

11. The transmitting device according to claim 3, wherein: The first preamble sequence included in the plurality of candidate preamble sequences in the first cell is a preamble sequence obtained by cyclically shifting the second preamble sequence included in the plurality of candidate preamble sequences in the second cell in units of code sequences.

12. The transmitting device according to claim 1, wherein: The first ZC (Zadoff-Chu) sequence after the cyclic prefix (CP) sent at the second RACH opportunity is the same as the first ZC sequence after the CP sent at the first RACH opportunity.

13. A receiving device comprising: A receiving circuit for receiving a signal from a random access channel; and The control circuit determines the preamble sequence included in the signal from a plurality of candidate preamble sequences, The preamble sequence is sent at least on the first random access channel, i.e., the first RACH timing and the second RACH timing, The number of ZC (Zadoff-Chu) sequences included in the preamble sequence varies for each cell.

14. The receiving device according to claim 13, wherein: The first ZC (Zadoff-Chu) sequence after the cyclic prefix (CP) sent at the second RACH opportunity is the same as the first ZC sequence after the CP sent at the first RACH opportunity.

15. A sending method, comprising: The transmitting device sets a preamble sequence for a signal of a random access channel from a plurality of candidate preamble sequences; as well as sending the signal of the random access channel, The preamble sequence is sent at least on the first random access channel, i.e., the first RACH timing and the second RACH timing, The number of ZC (Zadoff-Chu) sequences included in the preamble sequence varies for each cell.

16. The sending method according to claim 15, wherein: The first ZC (Zadoff-Chu) sequence after the cyclic prefix (CP) sent at the second RACH opportunity is the same as the first ZC sequence after the CP sent at the first RACH opportunity.

17. A receiving method, comprising: The receiving device receives a signal of a random access channel; as well as Determine the preamble sequence included in the signal from a plurality of candidate preamble sequences, The preamble sequence is received at least at the first random access channel, i.e., the first RACH timing and the second RACH timing, The number of ZC (Zadoff-Chu) sequences included in the preamble sequence varies for each cell.

18. The receiving method according to claim 17, wherein: The first ZC (Zadoff-Chu) sequence after the cyclic prefix (CP) sent at the second RACH opportunity is the same as the first ZC sequence after the CP sent at the first RACH opportunity.

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