Downstream synchronization signal transmission method, device, base station, and readable storage medium

Abstract

This application discloses a method, an apparatus, a base station, and a readable storage medium for transmitting a downlink synchronization signal, which includes the steps of: obtaining an operating bandwidth and device data of a signal receiving end; determining an extension number of the basic bandwidth of the downlink synchronization signal according to the basic bandwidth of the downlink synchronization signal and the operating bandwidth; generating a basic sequence corresponding to the basic bandwidth of the downlink synchronization signal according to the device data and a predetermined subcarrier spacing; reconstructing the basic sequence according to the extension number and a sequence structure of the basic sequence to obtain a target reconstructed sequence that is compatible with the operating bandwidth; and generating a downlink synchronization signal according to the target reconstructed sequence and sending it to the signal receiving end.

Description

[Technical Field]

[0001] (Related Applications) This application claims priority from a Chinese patent application bearing application number 202310256186.6, filed on March 2, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the technical field of industrial networks, and in particular to a method, an apparatus, a base station and a readable storage medium for transmitting a downstream synchronization signal. [Background technology]

[0003] Downlink synchronization is a very important step in the development of wireless networks. Downlink synchronization occurs when a terminal user powers on and starts up, establishing time and frequency synchronization of the downlink transmission link with the base station, and then using cell search to quickly identify the cell number of the cell in which the terminal is located. The terminal then initiates the random access process and establishes uplink synchronization. After uplink and downlink synchronization, the terminal obtains detailed system information about the cell and information about neighboring cells, allowing it to initiate calls and monitor paging, and the base station can correctly demodulate information sent by the user equipment (UE).

[0004] With the increase in communication users and the improvement of communication quality demands, the introduction of "cells" and "small cells" has led to users needing a more stable downlink synchronization process to assist in a series of steps such as cell search and cell switching to meet user communication requirements. Therefore, an accurate and stable downlink synchronization process is essential for user communication.

[0005] In conventional wireless local area networks (WLANs), the Long Term Evolution (LTE) and New Radio (NR) systems led by the Third Generation Partnership Project (3GPP®), when a terminal synchronizes time and frequency with a network, it can only use signals that it can receive within its own operating bandwidth, i.e., the operating bandwidth excluding guard bands. Generally, since there may be terminals with various operating bandwidths in a network, in order to allow access by terminals with the minimum operating bandwidth, the frequency domain range occupied by the synchronization signal broadcast by the base station must, in principle, be smaller than the minimum operating bandwidth specified in the protocol. For example, even a terminal with a 10 / 20 MHz bandwidth can only use synchronization signals within 5 MHz. This prevents the terminal from fully utilizing frequency domain resources for synchronization, wasting opportunities to improve synchronization detection performance. Summary of the Invention [Problem to be solved by the invention]

[0006] The main objective of the present application is to provide a method, apparatus, base station and readable storage medium for transmitting a downlink synchronization signal, which aims to solve the problem that a terminal cannot synchronize by fully utilizing the frequency domain resources of a base station. [Means for solving the problem]

[0007] In order to achieve the above object, the present application provides a method for transmitting a downlink synchronization signal, the method for transmitting a downlink synchronization signal comprising: Obtaining an operating bandwidth and device data of a signal receiving end; determining an extension count of the basic bandwidth of the downlink synchronization signal based on the basic bandwidth of the downlink synchronization signal and the operating bandwidth; generating a basic sequence corresponding to a basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier interval; reconstructing the base sequence based on the number of extensions and the sequence structure of the base sequence to obtain a target reconstructed sequence that fits the operating bandwidth; generating a downstream synchronization signal based on the target reconfiguration sequence and sending the downstream synchronization signal to the signal receiving end;

[0008] In one embodiment, the step of generating a basic sequence corresponding to a basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier interval includes: determining a sequence structure of a base sequence based on the device data and a predetermined subcarrier interval; determining a length of a base sequence based on the sequence structure, a predetermined number of valid data subcarriers, and a predetermined number of DC subcarriers; generating a base sequence based on the length of the sequence.

[0009] In one embodiment, the step of determining a sequence structure of a basic sequence based on the device data and a predetermined subcarrier interval includes: calculating a maximum frequency offset range of the signal receiving end based on the device data; determining whether the maximum frequency offset range is larger or smaller than the predetermined subcarrier spacing; and determining that, when the predetermined subcarrier spacing is smaller than the maximum frequency offset range, it is necessary to insert zero values ​​between non-zero values ​​in a base sequence for the sequence structure.

[0010] In one embodiment, the step of determining the sequence length of the base sequence based on the sequence structure, the predetermined number of valid data subcarriers, and the predetermined number of DC subcarriers includes: determining a first length of the base sequence based on a predetermined number of valid data subcarriers; calculating a second length of the target reconstruction sequence based on the sequence structure and the first length, and calculating a sum of the second length and a predetermined number of DC subcarriers; If the added value is equal to or less than the preset number of valid data subcarriers, setting the first length to the length of the target reconstruction sequence.

[0011] In one embodiment, the step of generating a base sequence based on the length of the sequence comprises: determining a root value of a base sequence based on the length of the sequence, the root value being a positive integer less than the length of the sequence; generating a base sequence based on the length of the sequence and the root value.

[0012] In one embodiment, the step of reconstructing the base sequence based on the number of extensions and the sequence structure of the base sequence to obtain a target reconstructed sequence adapted to the operating bandwidth includes: Extending the basic sequence based on the extension count and the sequence structure of the basic sequence to obtain an extended sequence; and performing subcarrier mapping on the extended sequence to obtain a target reconstructed sequence that is adapted to the operating bandwidth.

[0013] In one embodiment, the step of extending the basic sequence based on the extension count and the sequence structure of the basic sequence to obtain an extended sequence includes: According to a sequence structure of the base sequence, inserting a predetermined DC subcarrier into the base sequence and inserting zero values ​​between non-zero values ​​to obtain a first base sequence; and extending the first basic sequence based on the extension count to obtain an extended sequence.

[0014] In one embodiment, the step of performing subcarrier mapping on the extended sequence to obtain a target reconstructed sequence adapted to the operating bandwidth includes: The method includes mapping the extended sequence to the predetermined effective data subcarriers centered on the predetermined DC subcarrier to obtain a target reconstructed sequence that fits the operating bandwidth.

[0015] In one embodiment, the step of determining the number of times of extension of the basic bandwidth of the downlink synchronization signal based on the basic bandwidth of the downlink synchronization signal and the operating bandwidth includes: determining a multiple of the basic bandwidth of the downlink synchronization signal and the operating bandwidth based on the basic bandwidth of the downlink synchronization signal and the operating bandwidth; The method includes a step of setting the multiple to be the number of times the sequence is extended, the number corresponding to the basic bandwidth of the downlink synchronization signal.

[0016] In order to achieve the above object, the present application provides a downlink synchronization signal transmission device, the downlink synchronization signal transmission device comprising: a bandwidth acquisition module for acquiring the operating bandwidth and device data of the signal receiving end; an extension number determination module for determining an extension number of the basic bandwidth of the downlink synchronization signal according to the basic bandwidth of the downlink synchronization signal and the operating bandwidth; a sequence generating module for generating a basic sequence corresponding to a basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier interval; a sequence reconstruction module for reconstructing the base sequence based on the extension count and a sequence structure of the base sequence to obtain a target reconstructed sequence that is compatible with the operating bandwidth; a signal transmitting module for generating a downstream synchronization signal according to the target reconfiguration sequence and transmitting the downstream synchronization signal to the signal receiving end;

[0017] In addition, in order to achieve the above object, the present application further provides a base station, which includes a memory, a processor, and a downlink synchronization signal transmission program stored in the memory and executable on the processor, and when the downlink synchronization signal transmission program is executed by the processor, it realizes the steps of the above-mentioned downlink synchronization signal transmission method.

[0018] In addition, in order to achieve the above object, the present application further provides a readable storage medium, in which a downlink synchronization signal transmission program is stored, and when the downlink synchronization signal transmission program is executed by a processor, the steps of the above-mentioned downlink synchronization signal transmission method are realized. (Effects of the Invention)

[0019] This application provides a method, apparatus, base station, and readable storage medium for transmitting a downlink synchronization signal. The method includes: obtaining an operating bandwidth and device data of a signal receiving end; determining a basic bandwidth of a downlink synchronization signal and an extension count for the basic bandwidth of the downlink synchronization signal based on the operating bandwidth; generating a basic sequence corresponding to the basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier spacing, thereby realizing the generation of a basic bandwidth when sequence extension is not required and providing a basic sequence for sequence extension; performing sequence reconfiguration on the basic sequence based on the extension count and the sequence structure of the basic sequence to obtain a target reconfigured sequence that is compatible with the operating bandwidth; generating a downlink synchronization signal based on the target reconfigured sequence and transmitting it to the signal receiving end; extending the basic bandwidth transmitted by the base station; and obtaining a signal sequence that is compatible with the bandwidth of the signal receiving end, so that the signal receiving end can fully utilize its wide bandwidth for signal synchronization. The sequence can be reconfigured to a sequence that is compatible with the operating bandwidth so that the signal receiving end can receive this bandwidth. The present application generates a sequence as a synchronization sequence for a basic bandwidth and extends it to a sequence that supports a wider bandwidth, thereby enabling the signal receiving end to maximize the use of the base station's frequency domain resources for synchronization and improve the utilization rate of the synchronization signal. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a schematic diagram illustrating a hardware operating environment related to an embodiment of a method for transmitting a downlink synchronization signal according to the present invention. [Figure 2] 3 is a flowchart of a first embodiment of a method for transmitting a downlink synchronization signal according to the present invention. [Figure 3] 10 is a flowchart of a second embodiment of a method for transmitting a downlink synchronization signal according to the present invention. [Figure 4] 10 is a flowchart of a third embodiment of a method for transmitting a downlink synchronization signal according to the present invention. [Figure 5]1 is a schematic diagram showing a sequence configuration when the operating bandwidth after zero insertion is 20 MHz in the downlink synchronization signal transmission method of the present application. [Figure 6] 1 is a schematic diagram showing an extended sequence configuration when the operating bandwidth is 40 MHz in the downlink synchronization signal transmission method of the present application. [Figure 7] 1 is a schematic diagram showing an extended sequence configuration when the operating bandwidth is 80 MHz in the downlink synchronization signal transmission method of the present application. [Figure 8] 1 is a schematic diagram showing a subcarrier mapping method in a downlink synchronization signal transmission method of the present application. [Figure 9] 1 is a schematic diagram of a transmission device for a downlink synchronization signal according to the present invention. The realization of the object of the present invention, the features and advantages of the functions will be further described in conjunction with the embodiments with reference to the drawings. DETAILED DESCRIPTION OF THE INVENTION

[0021] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be described in more detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are for illustrative purposes only and are not intended to limit the present application.

[0022] As shown in FIG. 1, FIG. 1 is a diagram showing the terminal configuration of the hardware operating environment according to the embodiment of the present invention.

[0023] The terminal according to the embodiment of the present application is a base station.

[0024] As shown in FIG. 1 , the terminal may include a processor 1001 (e.g., a CPU), a communication bus 1002, a user interface 1003, a DVI interface 1004, a USB interface 1005, and a memory 1006. The communication bus 1002 is used to connect and communicate between these components. The user interface 1003 may include a display and an input unit such as a keyboard, and may further include a standard wired interface and a wireless interface. The DVI interface 1004 may include a standard wired interface connected to other external devices via a DVI cable. The USB interface 1005 may include a standard wired interface connected to other external devices via a USB connection cable. The memory 1006 may be a high-speed RAM memory or a non-volatile memory such as a disk memory. The memory 1006 may also be a storage device independent of the processor 1001.

[0025] In one embodiment, the terminal may further include audio circuitry etc., which will not be further described here.

[0026] Those skilled in the art will appreciate that the terminal structure shown in FIG. 1 is not limiting and the terminal may include more or fewer components than shown, and certain components may be combined or arranged in different components.

[0027] As shown in FIG. 1, the memory 1006, which is a computer storage medium, can include an operating system, a DVI interface module, a USB interface module, a user interface module, and a downstream synchronization signal transmission program.

[0028] In the terminal shown in FIG. 1, the DVI interface 1004 is mainly connected to an external device and used for data communication with the external device. The USB interface 1005 is mainly connected to an external device and used for data communication with the external device. The user interface 1003 is mainly connected to a client and used for data communication with the client. The processor 1001 may be used to call a downlink synchronization signal transmission program stored in the memory 1006, and performs the following operations: Obtaining an operating bandwidth and device data of the signal receiving end; determining an extension count of the basic bandwidth of the downlink synchronization signal based on the basic bandwidth of the downlink synchronization signal and the operating bandwidth; generating a basic sequence corresponding to a basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier interval; reconstructing the base sequence based on the number of extensions and a sequence structure of the base sequence to obtain a target reconstructed sequence that is adapted to the operating bandwidth; A downstream synchronization signal is generated based on the target reconfiguration sequence and sent to the signal receiving end.

[0029] Furthermore, the processor 1001 may call a downlink synchronization signal transmission program stored in the memory 1006, and perform the following operations: determining a sequence structure of a basic sequence based on the device data and a predetermined subcarrier interval; determining a number of valid data subcarriers based on the operating bandwidth, the predetermined subcarrier spacing, and a predetermined number of guard subcarriers; determining a length of the base sequence based on the sequence structure, the number of valid data subcarriers, and a predetermined number of DC subcarriers; A base sequence is generated based on the length of the sequence.

[0030] Furthermore, the processor 1001 may call a downlink synchronization signal transmission program stored in the memory 1006, and perform the following operations: Calculating a maximum frequency offset range of the signal receiving end based on the device data; determining whether the maximum frequency offset range is larger or smaller than the predetermined subcarrier interval; If the predetermined subcarrier spacing is smaller than the maximum frequency offset range, it is determined that a zero value needs to be inserted between non-zero values ​​in the base sequence for the sequence structure.

[0031] Furthermore, the processor 1001 may call a downlink synchronization signal transmission program stored in the memory 1006, and perform the following operations: determining a first length of a base sequence based on the number of valid data subcarriers; Calculating a second length of the target reconstruction sequence based on the sequence structure and the first length, and calculating a sum of the second length and a predetermined number of DC subcarriers; If the added value is equal to or less than the preset number of valid data subcarriers, the first length is set as the length of the target reconstruction sequence.

[0032] Furthermore, the processor 1001 may call a downlink synchronization signal transmission program stored in the memory 1006, and perform the following operations: determining a root value of a base sequence based on the length of the sequence, the root value being a positive integer less than the length of the sequence; A base sequence is generated based on the length of the sequence and the root value.

[0033] Furthermore, the processor 1001 may call a downlink synchronization signal transmission program stored in the memory 1006, and perform the following operations: Extending the basic sequence based on the extension count and the sequence structure of the basic sequence to obtain an extended sequence; Subcarrier mapping is performed on the extended sequence to obtain a target reconstructed sequence that fits the operating bandwidth.

[0034] Furthermore, the processor 1001 may call a downlink synchronization signal transmission program stored in the memory 1006, and perform the following operations: According to a sequence structure of the base sequence, insert a predetermined DC subcarrier and a predetermined guard subcarrier into the base sequence, and insert zero values ​​between non-zero values ​​to obtain a first base sequence; The first basic sequence is extended based on the extension count to obtain an extended sequence.

[0035] Furthermore, the processor 1001 may call a downlink synchronization signal transmission program stored in the memory 1006, and perform the following operations: The reconstructed sequence is mapped to the effective data subcarriers of a target reconstructed sequence, centered on the predetermined DC subcarrier, to obtain a target reconstructed sequence that is adapted to the operating bandwidth.

[0036] Furthermore, the processor 1001 may call a downlink synchronization signal transmission program stored in the memory 1006, and perform the following operations: determining a multiple of the basic bandwidth of the downlink synchronization signal and the operating bandwidth based on the basic bandwidth of the downlink synchronization signal and the operating bandwidth; The multiple is set as the number of times the sequence is extended, corresponding to the basic bandwidth of the downlink synchronization signal.

[0037] The specific embodiments of the base station of the present invention are basically the same as the embodiments of the downlink synchronization signal transmission program described later, and therefore will not be further described here.

[0038] Referring to FIG. 2, FIG. 2 is a flowchart of a first embodiment of the method for transmitting a downlink synchronization signal of the present invention, and the method for transmitting a downlink synchronization signal according to this embodiment includes the following steps. Step S10: Obtain the operating bandwidth and device data of the signal receiving end. This application applies to a base station, i.e., a public mobile communication base station, which is an interface device through which a signal receiving end accesses the Internet. Here, the relevant signal receiving end, i.e., user equipment (UE), can represent any applicable end-user equipment, such as a wireless transmit / receive unit (WTRU), a mobile station, a mobile node, a mobile device, a fixed or mobile subscriber unit, a pager, a mobile phone, a personal digital assistant (PDA), a smartphone, a laptop, a computer, a touchscreen device, a wireless sensor, or a home appliance. The operating bandwidth refers to the operating frequency range of the signal receiving end, including 20 MHz, 40 MHz, and 80 MHz. The base station can acquire the operating bandwidth of the signal receiving end from the signal broadcast by the signal receiving end. The device data refers to the hardware data of the signal receiving end, i.e., the crystal oscillator.

[0039] Step S20: determining the extension times of the basic bandwidth of the downlink synchronization signal according to the basic bandwidth of the downlink synchronization signal and the operating bandwidth; In a wireless communication system, downlink synchronization between a base station and a signal receiving end is achieved by transmitting a synchronization sequence and the signal receiving end detecting the sequence. Therefore, in the process of downlink synchronization between a base station and a signal receiving end, synchronization is achieved based on a sequence corresponding to the basic bandwidth of the base station. Here, the basic bandwidth refers to the minimum bandwidth that the base station can transmit. The operating bandwidth refers to the bandwidth used by the signal receiving end when it is operating.

[0040] In a preferred embodiment, the basic bandwidth is set to 20 MHz. When the operating bandwidth is 20 MHz, there is no need to extend, i.e., the number of extensions is set to 0. When the operating bandwidth is 40 MHz, the sequence needs to be extended twice. When the operating bandwidth is 80 MHz, the sequence needs to be extended four times.

[0041] Specifically, in one embodiment, step S20 includes: A step A21 of determining a multiple of the basic bandwidth of the downlink synchronization signal and the operating bandwidth based on the basic bandwidth of the downlink synchronization signal and the operating bandwidth; The method further includes step A22 of setting the multiple to the number of extensions of the sequence corresponding to the basic bandwidth of the downlink synchronization signal. In this embodiment, in one communication system, the basic bandwidth may be set to 20 MHz, and the operating bandwidth includes 20 MHz, 40 MHz, and 80 MHz. When the operating bandwidth is 20 MHz, it indicates that there is no need to extend the sequence, and the multiple is 0, that is, the number of extensions is 0. The operating bandwidth is represented by K, and when it is 40 MHz or 80 MHz, K=20 MHz*(2^N), N=1, 2, that is, the multiple of the basic bandwidth and the operating bandwidth is [2^N], N=1, 2, that is, the number of extensions is 2 or 4.

[0042] Step S30: generating a basic sequence corresponding to a basic bandwidth of the downlink synchronization signal according to the device data and a preset subcarrier interval. In a preferred embodiment, the preset subcarrier spacing is selected to be 78.125 kHz. Of course, those skilled in the art can select 156.25 kHz as needed, but the present application is not limited thereto. Because the base station and the signal receiving end need to synchronize via a sequence, a basic sequence that matches the basic bandwidth is first generated, and then the basic sequence can be extended according to the extension number.

[0043] Step S40: reconstructing the base sequence based on the extension number and the sequence structure of the base sequence to obtain a target reconstructed sequence that is compatible with the operating bandwidth; The number of extensions includes 0, 2, and 4, and the sequence structure includes a structure that requires zero insertion within the sequence and a structure that does not require zero insertion within the sequence. When the number of extensions is 2 or 4, or the sequence structure requires zero insertion, sequence reconstruction is required, and the sequence reconstruction includes extension and subcarrier mapping. For specific reconstruction methods, please refer to the following examples and no further description is provided in this application.

[0044] Step S50: generating a downstream synchronization signal according to the target reconfiguration sequence and sending it to the signal receiving end.

[0045] After obtaining the target reconstruction sequence, an inverse Fourier transform (IFFT) is performed based on the set subcarrier spacing. IFFT Here, N IFFT can be obtained by calculating the quotient of the basic bandwidth and the subcarrier spacing. If the subcarrier spacing is 78.125 kHz and the basic bandwidth is 20 MHz, then N IFFT =256.

[0046] To generate a downlink synchronization signal, the target reconstructed sequence needs to be subjected to an inverse Fourier transform (IFFT) and then a cyclic prefix (CP) is added to generate the downlink synchronization signal. Here, the IFFT transform refers to a 256-point IFFT transform on the generated target reconstructed sequence. The CP is added in front of the mapped sequence time-domain signal and is obtained by truncating the end of the mapped sequence time-domain signal.

[0047] The present application provides a method for transmitting a downlink synchronization signal. The method obtains an operating bandwidth and device data of a signal receiving end, determines a basic bandwidth of a downlink synchronization signal and an extension count for the basic bandwidth of the downlink synchronization signal based on the operating bandwidth, and generates a base sequence corresponding to the basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier spacing. This realizes the generation of the basic bandwidth when sequence extension is not required and provides a base sequence for sequence extension. Based on the extension count and the sequence structure of the base sequence, sequence reconfiguration is performed on the base sequence to obtain a target reconfigured sequence that is compatible with the operating bandwidth. A downlink synchronization signal is generated based on the target reconfigured sequence and transmitted to the signal receiving end. This extends the basic bandwidth transmitted from the base station, thereby obtaining a signal sequence that is compatible with the bandwidth of the signal receiving end, allowing the signal receiving end to fully utilize its own wide bandwidth for signal synchronization. The signal receiving end can then reconfigure the sequence to a sequence that is compatible with the operating bandwidth so that it can receive this bandwidth. The present application generates a sequence as a synchronization sequence for the basic bandwidth and then extends it to a sequence that supports a wider bandwidth, allowing the signal receiving end to fully utilize the frequency domain resources of the base station for synchronization and improve the utilization rate of the synchronization signal.

[0048] Further, referring to FIG. 3, a second embodiment of the present invention is proposed based on the first embodiment of the method for transmitting a downlink synchronization signal of the present invention, and the step S30 is as follows: The method further includes a step S31 of determining a sequence structure of a basic sequence based on the device data and a predetermined subcarrier interval; There are two sequence structures: one that requires zero insertion into the sequence, and one that does not require zero insertion into the sequence. Inserting zeros is the insertion of virtual subcarriers into the sequence so that the sequence is repeated twice in the time domain.

[0049] Specifically, in one embodiment, the step S31 further includes the following steps: Step A311: calculating the maximum frequency offset range of the signal receiving end according to the device data; The device data is the crystal oscillator of the signal receiving end. After determining the crystal oscillator of the signal receiving end, the center frequency of the crystal oscillator is calculated based on the crystal oscillator, and then the maximum frequency offset range of the signal receiving end is determined based on the center frequency. For example, if the accuracy of the crystal oscillator is <±10 ppm, and the center frequency is assumed to be 5.8 GHz, the maximum frequency offset range of the signal receiving end is calculated to be ±58 kHz. If the center frequency is assumed to be 3.33 GHz, the center frequency of the crystal oscillator is ±33.33 kHz. As a preferred embodiment, the communication system described herein selects ±58 kHz as the maximum frequency offset range. Step A312: determining whether the maximum frequency offset range is larger or smaller than the predetermined subcarrier interval; Step A313: if the predetermined subcarrier spacing is smaller than the maximum frequency offset range, it is determined that a zero value needs to be inserted between non-zero values ​​in the base sequence for the sequence structure.

[0050] To ensure that the preset subcarrier spacing is greater than the maximum frequency offset range and cover the maximum frequency offset range, it is necessary to determine the difference between the two. In this embodiment, under the condition that the subcarrier spacing SCS = 78.125 kHz, the time domain sequence can be repeated twice by inserting one zero into the interval, resulting in an actual sequence symbol length of 12.8 us, and the frequency offset estimation range is ±(1 / 6.4 / 2) = ±78.125 kHz > ±58 kHz, which meets the system requirements. Therefore, in this embodiment, zero insertion is required.

[0051] Note that a sequence is formed by a plurality of subcarriers, including real subcarriers and virtual subcarriers, where a non-zero value refers to a real subcarrier and can be represented by 1. A zero refers to a virtual subcarrier and can be represented by 0. Therefore, inserting zeros means inserting zeros every other time in the sequence.

[0052] Step S32: Determine the length of a basic sequence according to the sequence structure, the preset number of valid data subcarriers, and the preset number of DC subcarriers; The preset effective data subcarriers refer to effective data subcarriers corresponding to the operating bandwidth. Specifically, the number of the preset effective data subcarriers may be 240.

[0053] In one embodiment, the step S32 further includes the following steps: Step A321: determining a first length of a base sequence based on a preset number of valid data subcarriers; When determining the first length, a first length smaller than the number of valid data subcarriers may be selected, for example, if the number of valid data subcarriers is 240, 110, 111, or 112 smaller than 240 may be selected as the first length, and in this embodiment, 113 will be selected as the preferred first length in the following description. Note that when selecting the first length, a length smaller than half the number of valid data subcarriers may be preferentially selected as the first length so that the final sequence length is smaller than the number of valid data subcarriers.

[0054] Step A322: calculate a second length of the target reconstruction sequence based on the sequence structure and the first length, and calculate the sum of the second length and a preset number of DC subcarriers.

[0055] In this embodiment, the preset DC subcarrier is located at the middle position of the sequence, that is, the DC subcarrier in FIG.

[0056] Specifically, when calculating the second length and the additional value, if the first length is 113 and the sequence structure requires zero insertion, the second length becomes 113×2−1, or 225, because every other zero is inserted into the sequence, and the additional value becomes 228. If the sequence structure does not require zero insertion, the second length remains 113, and the additional value becomes 116.

[0057] Step A323: if the added value is smaller than the preset number of valid data subcarriers, the first length is set as the length of the target reconstruction sequence.

[0058] Step A324: if the added value is greater than the number of valid data subcarriers, execute step A331 until the added value is equal to or less than the number of valid data subcarriers.

[0059] In this embodiment, to avoid the problem that subcarrier mapping cannot be performed for the reconstructed sequence subsequently generated based on the length of the sequence, the first length can be determined as the length of the target reconstructed sequence only if the added value is smaller than the number of valid data subcarriers.

[0060] Step S33: Generate a base sequence based on the length of the sequence.

[0061] In one embodiment, the step S33 further includes the following steps: Step A331: determine a root value of a basic sequence according to the length of the sequence, where the root value is a positive integer less than the length of the sequence; If the length of the sequence is 113, the root value is 1, 2, 3, ..., 112, that is, one of the positive integers less than 113, and is represented by u. The specific root value can be arbitrarily selected within this range, and the present application is not limited thereto.

[0062] Step A332 generates a base sequence based on the length of the sequence and the root value.

[0063] A reconstructed sequence is generated by the following formula, and the reconstructed sequence is a ZC sequence:

number

[0064] In the present application, the sequence structure of the basic sequence is determined based on the device data and the preset subcarrier spacing, and then the length of the basic sequence is determined based on the sequence structure, the preset number of valid data subcarriers, and the preset number of DC subcarriers, and the basic sequence is generated based on the length of the sequence, thereby realizing the generation of basic bandwidth when sequence extension is not required and providing a basic sequence for sequence extension.

[0065] Further, referring to Fig. 4, a third embodiment of the present invention is proposed based on the first embodiment of the method for transmitting a downlink synchronization signal of the present invention. The step S40 further includes the following steps: Step S41: extending the basic sequence based on the extension count and the sequence structure of the basic sequence to obtain an extended sequence; If the number of extensions is 2 or 4, or if the sequence structure requires zero insertion, the base sequence needs to be extended.

[0066] Specifically, in one embodiment, the step A41 further includes the following steps: Step A411: according to the sequence structure of the basic sequence, insert a preset DC subcarrier into the basic sequence, and insert zero values ​​between non-zero values ​​to obtain a first basic sequence.

[0067] Referring to Figure 5, it is a schematic diagram showing the sequence structure when the bandwidth after zero insertion is 20 MHz. The shaded area is a value of 0, and the areas on both sides of the shaded area are a value of 1. If the sequence structure requires a zero insertion operation, a zero is inserted every other time in the base sequence. For example, the length of the base sequence is 113, and after the zero insertion operation, the length of the first base sequence obtained is 225.

[0068] In addition, the number of preset DC subcarriers can be set to three according to the communication standard protocol, and the length of the first basic sequence after inserting the preset DC subcarriers is 228.

[0069] Step A412: extend the first basic sequence based on the extension count to obtain an extended sequence.

[0070] If the extension count is 0, it indicates that the sequence does not need to be extended, and the resulting extended sequence remains the original basic sequence. If the extension count is 2, from the perspective of sequence symmetry, the sequence is copied twice and inverted twice to obtain an extended sequence with a 40 MHz bandwidth. Specifically, referring to Figures 5 and 6, Figure 5 is a schematic diagram showing the sequence structure when the bandwidth is 20 MHz, and Figure 6 is a schematic diagram showing the extended sequence structure when the bandwidth is 40 MHz. The schematic diagram of the 20 MHz sequence structure is copied twice and inverted twice to obtain the 40 MHz structure diagram in Figure 6. Of these, the 20 MHz basicSince the basic sequence in the bandwidth has the characteristic of central symmetry, SEQ1 = SEQ2 in the figure. After copying SEQ1 and SEQ2 to both ends of the basic bandwidth respectively and then inverting them, the sequence structure shown in Figure 6 is obtained.

[0071] When the number of extensions is four, refer to Fig. 7, which is a schematic diagram of the corresponding sequence structure when the bandwidth is 80 MHz. When the basic bandwidth is 20 MHz, the corresponding basic sequence is copied four times and inverted four times to obtain the sequence structure shown in Fig. 7.

[0072] Step S42: Subcarrier mapping is performed on the extended sequence to obtain a target reconstructed sequence that is compatible with the operating bandwidth.

[0073] Subcarrier mapping refers to mapping the spreading sequence onto useful data subcarriers.

[0074] Specifically, in one embodiment, step A42 further includes the following steps: Step A421: centering on the preset DC subcarrier, mapping the extension sequence to the preset effective data subcarriers to obtain a target reconstruction sequence that is compatible with the operating bandwidth.

[0075] Referring to FIG. 8, FIG. 8 is a schematic diagram of a subcarrier mapping scheme, in which the preset valid data subcarriers of the target reconstruction sequence may be set to 240, where 0 in FIG. 8 represents the DC subcarrier and k is 120. Since the length of the extension sequence is 228, when performing subcarrier mapping, the DC subcarrier is used as the center and the extension sequence is mapped to the preset valid data subcarriers on both sides one by one. If the length of the extension sequence, i.e., the number of subcarriers, does not match the number of preset valid data subcarriers, zeros are padded on both sides of the extension sequence until the length of the extension sequence matches the preset valid data subcarriers. That is, the subcarrier mapping is completed and a target reconstruction sequence that is compatible with the operating bandwidth is obtained.

[0076] In this application, the basic sequence is extended based on the extension count and the sequence structure of the basic sequence to obtain an extended sequence, and subcarrier mapping is performed on the extended sequence to obtain a target reconstruction sequence that is compatible with the operating bandwidth. The synchronization sequence is generated for the basic bandwidth, and then extended to a sequence that supports a wider bandwidth using a stepwise copy and inversion method, thereby improving the utilization rate of the synchronization signal.

[0077] Also, referring to FIG. 9, the embodiment of the present application further proposes a downlink synchronization signal transmitting device, and the downlink synchronization signal transmitting device comprises: A bandwidth acquisition module (01) for acquiring the operating bandwidth and device data of a signal receiving end; an extension number determination module (02) for determining the extension number of the basic bandwidth of the downlink synchronization signal according to the basic bandwidth of the downlink synchronization signal and the operating bandwidth; a sequence generating module (03) for generating a basic sequence corresponding to a basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier interval; a sequence reconstruction module (04) for reconstructing the base sequence based on the extension number and the sequence structure of the base sequence to obtain a target reconstructed sequence adapted to the operating bandwidth; and a signal transmitting module (05) for generating a downstream synchronization signal based on the target reconfiguration sequence and transmitting the generated downstream synchronization signal to the signal receiving end.

[0078] An embodiment of the present application further provides a readable storage medium, the readable storage medium storing a downlink synchronization signal transmission program, which, when executed by a processor, realizes the following operations: Obtaining an operating bandwidth and device data of the signal receiving end; determining an extension count of the basic bandwidth of the downlink synchronization signal based on the basic bandwidth of the downlink synchronization signal and the operating bandwidth; generating a basic sequence corresponding to a basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier interval; reconstructing the base sequence based on the number of extensions and a sequence structure of the base sequence to obtain a target reconstructed sequence that is adapted to the operating bandwidth; A downstream synchronization signal is generated based on the target reconfiguration sequence and sent to the signal receiving end.

[0079] Furthermore, when the downlink synchronization signal transmission program is executed by a processor, the following operations are further realized: determining a sequence structure of a basic sequence based on the device data and a predetermined subcarrier interval; determining a length of a base sequence based on the sequence structure, the predetermined number of valid data subcarriers, and the predetermined number of DC subcarriers; A base sequence is generated based on the length of the sequence.

[0080] Furthermore, when the position detection program is executed by a processor, the following operations are further realized: Calculating a maximum frequency offset range of the signal receiving end based on the device data; determining whether the maximum frequency offset range is larger or smaller than the predetermined subcarrier interval; If the predetermined subcarrier spacing is smaller than the maximum frequency offset range, it is determined that a zero value needs to be inserted between non-zero values ​​in the base sequence for the sequence structure.

[0081] Furthermore, when the downlink synchronization signal transmission program is executed by a processor, the following operations are further realized: determining a first length of the base sequence based on a predetermined number of valid data subcarriers; Calculating a second length of the target reconstruction sequence based on the sequence structure and the first length, and calculating a sum of the second length and a predetermined number of DC subcarriers; If the added value is equal to or less than the preset number of valid data subcarriers, the first length is set as the length of the target reconstruction sequence.

[0082] Furthermore, when the downlink synchronization signal transmission program is executed by a processor, the following operations are further realized: determining a root value of a base sequence based on the length of the sequence, the root value being a positive integer less than the length of the sequence; A base sequence is generated based on the length of the sequence and the root value.

[0083] Furthermore, when the downlink synchronization signal transmission program is executed by a processor, the following operations are further realized: Extending the basic sequence based on the extension count and the sequence structure of the basic sequence to obtain an extended sequence; Subcarrier mapping is performed on the extended sequence to obtain a target reconstructed sequence that fits the operating bandwidth.

[0084] Furthermore, when the downlink synchronization signal transmission program is executed by a processor, the following operations are further realized: According to a sequence structure of the base sequence, insert a predetermined DC subcarrier into the base sequence and insert zero values ​​between non-zero values ​​to obtain a first base sequence; The first basic sequence is extended based on the extension count to obtain an extended sequence.

[0085] Furthermore, when the downlink synchronization signal transmission program is executed by a processor, the following operations are further realized: The extended sequence is mapped to the predetermined effective data subcarriers centered on the predetermined DC subcarrier to obtain a target reconstructed sequence that is compatible with the operating bandwidth.

[0086] Furthermore, when the downlink synchronization signal transmission program is executed by a processor, the following operations are further realized: determining a multiple of the basic bandwidth of the downlink synchronization signal and the operating bandwidth based on the basic bandwidth of the downlink synchronization signal and the operating bandwidth; The multiple is set as the number of times the sequence is extended, corresponding to the basic bandwidth of the downlink synchronization signal.

[0087] The readable storage medium may be the memory 1006 in the terminal of FIG. 1, or at least one of a ROM (Read-Only Memory) / RAM (Random Access Memory), a magnetic disk, and an optical disk, and the readable storage medium contains some information for causing the terminal to execute the methods described in each embodiment of the present application.

[0088] It should be noted that, as used herein, "comprises," "including," or any other variation thereof, is intended to encompass a non-exclusive inclusion, and thus a process, method, article, or system that includes a set of elements includes not only those elements but also other elements not expressly listed or that are inherent in such process, method, article, or system. Absent further limitation, an element qualified by the phrase "comprises a ..." does not exclude the presence of other similar elements in the process, method, article, or system that includes that element.

[0089] The numbers of the above examples of the present application are for the purpose of explanation and do not indicate the superiority or inferiority of the examples.

[0090] Having described the above embodiments, it will be apparent to those skilled in the art that the methods of the above examples may be implemented either by software and a required general-purpose hardware platform, or by hardware, with the former being the more preferred embodiment in many cases.

[0091] The above is merely a preferred embodiment of the present application, and does not limit the scope of the claims of the present application. Any equivalent structure or equivalent process conversion made by utilizing the contents of the specification and drawings of the present application, or those operated directly or indirectly in other related technical fields, are included in the patent protection scope of the present application.

Claims

1. A method for transmitting a downlink synchronization signal, the method comprising: Obtaining an operating bandwidth and device data of a signal receiving end; determining an extension count of the basic bandwidth of the downlink synchronization signal based on the basic bandwidth of the downlink synchronization signal and the operating bandwidth; generating a basic sequence corresponding to a basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier interval; reconstructing the base sequence based on the number of extensions and the sequence structure of the base sequence to obtain a target reconstructed sequence that fits the operating bandwidth; generating a downlink synchronization signal based on the target reconfiguration sequence and transmitting the generated downlink synchronization signal to the signal receiving end.

2. generating a basic sequence corresponding to a basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier interval, determining a sequence structure of a base sequence based on the device data and a predetermined subcarrier interval; determining a length of a base sequence based on the sequence structure, a predetermined number of valid data subcarriers, and a predetermined number of DC subcarriers; The method for transmitting a downlink synchronization signal according to claim 1 , further comprising: generating a base sequence based on the length of the sequence.

3. The step of determining a sequence structure of a base sequence based on the device data and a predetermined subcarrier interval includes: calculating a maximum frequency offset range of the signal receiving end based on the device data; determining whether the maximum frequency offset range is larger or smaller than the predetermined subcarrier spacing; and determining, when the predetermined subcarrier spacing is smaller than the maximum frequency offset range, that it is necessary to insert zero values ​​between non-zero values ​​in a basic sequence for the sequence structure.

4. determining a length of the base sequence based on the sequence structure, a predetermined number of valid data subcarriers, and a predetermined number of DC subcarriers, determining a first length of the base sequence based on a predetermined number of valid data subcarriers; calculating a second length of the target reconstruction sequence based on the sequence structure and the first length, and calculating a sum of the second length and a predetermined number of DC subcarriers; 4. The method for transmitting a downlink synchronization signal according to claim 3, further comprising the step of: when the added value is equal to or less than the predetermined number of valid data subcarriers, setting the first length to the length of the target reconstruction sequence.

5. The step of generating a base sequence based on the length of the sequence comprises: determining a root value of a base sequence based on the length of the sequence, the root value being a positive integer less than the length of the sequence; 5. The method for transmitting a downlink synchronization signal according to claim 4, further comprising the step of: generating a base sequence based on the length of the sequence and the root value.

6. The step of reconstructing the base sequence based on the number of extensions and the sequence structure of the base sequence to obtain a target reconstructed sequence adapted to the operating bandwidth includes: Extending the basic sequence based on the extension count and the sequence structure of the basic sequence to obtain an extended sequence; 6. The method for transmitting a downlink synchronization signal according to claim 5, further comprising: performing subcarrier mapping on the extended sequence to obtain a target reconstructed sequence that is adapted to the operating bandwidth.

7. The step of extending the basic sequence based on the extension count and the sequence structure of the basic sequence to obtain an extended sequence includes: According to a sequence structure of the basic sequence, inserting a predetermined DC subcarrier into the basic sequence and inserting zero values ​​between non-zero values ​​to obtain a first basic sequence; 7. The method for transmitting a downlink synchronization signal according to claim 6, further comprising: extending the first basic sequence based on the number of extensions to obtain an extended sequence.

8. The step of performing subcarrier mapping on the extended sequence to obtain a target reconstructed sequence adapted to the operating bandwidth includes:

8. The method for transmitting a downlink synchronization signal according to claim 7, further comprising: mapping the extended sequence to the predetermined effective data subcarriers centered on the predetermined DC subcarrier to obtain a target reconstruction sequence adapted to the operating bandwidth.

9. The step of determining the number of times of extension of the basic bandwidth of the downlink synchronization signal based on the basic bandwidth of the downlink synchronization signal and the operating bandwidth includes: determining a multiple of a fundamental bandwidth of a downstream synchronization signal and an operating bandwidth; 2. The method for transmitting a downlink synchronization signal according to claim 1, further comprising the step of: setting the multiple to an extension number of the sequence corresponding to a basic bandwidth of the downlink synchronization signal.

10. A downlink synchronization signal transmitting device, a bandwidth acquisition module for acquiring the operating bandwidth and device data of the signal receiving end; an extension number determination module for determining an extension number of the basic bandwidth of the downlink synchronization signal according to the basic bandwidth of the downlink synchronization signal and the operating bandwidth; a sequence generating module for generating a basic sequence corresponding to a basic bandwidth of the downlink synchronization signal based on the device data and a predetermined subcarrier interval; a sequence reconstruction module for reconstructing the base sequence based on the extension count and a sequence structure of the base sequence to obtain a target reconstructed sequence that is compatible with the operating bandwidth; a signal transmitting module for generating the downlink synchronization signal according to the target reconfiguration sequence and transmitting the downlink synchronization signal to the signal receiving end.

11. A base station, Memory and a processor; a downlink synchronization signal transmission program stored in the memory and executable on the processor; A base station that, when the downlink synchronization signal transmission program is executed by the processor, implements the steps of the downlink synchronization signal transmission method according to any one of claims 1 to 9.

12. A readable storage medium having a downlink synchronization signal transmission program stored therein, the downlink synchronization signal transmission program realizing the steps of the downlink synchronization signal transmission method described in any one of claims 1 to 9 when executed by a processor.

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