Frame synchronization method, apparatus, device and medium for wireless communication system

Abstract

The application relates to a frame synchronization method, device, equipment and medium for a wireless communication system. The method comprises the following steps: preprocessing a long preamble sequence of a received signal to obtain a preprocessing signal; performing autocorrelation and modulus squaring on the preprocessing signal to obtain an autocorrelation result; performing shift storage on the preprocessing signal, performing cross-correlation and modulus squaring on the output sequence after the shift and the preprocessing local long preamble sequence to obtain a cross-correlation result; performing peak detection according to the product of the autocorrelation result, a local long preamble sequence autocorrelation modulus square threshold value and a peak value judgment threshold value and the cross-correlation result, and performing frame synchronization according to a peak detection result. The method can improve the frame synchronization precision and efficiency of the wireless communication system in a low signal-to-noise ratio environment.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to a frame synchronization method, apparatus, device, and medium for wireless communication systems. Background Technology

[0002] With the rapid development and widespread application of communication technology, Wireless Local Area Networks (WLANs) have become an indispensable part of people's daily lives and work. Among WLANs, the IEEE 802.11 standard, as the mainstream standard, has long been a hot research area for companies and universities. With the continuous improvement of performance requirements for communication systems, the importance of physical layer frame detection and synchronization in wireless communication reception has become increasingly prominent. Frame detection and synchronization, as the first step in the physical layer of wireless communication reception, directly affects the reception performance of the entire system. Synchronization algorithms can be broadly divided into two categories: time-domain synchronization and frequency-domain synchronization. Time-domain synchronization is usually based on correlation operations, and its core idea is to detect and synchronize frames through the correlation between signals. With the continuous improvement of synchronization accuracy requirements, various synchronization algorithms based on correlation operations have emerged and are constantly being improved and optimized.

[0003] Existing wireless LAN synchronization technologies often achieve frame timing synchronization through platform detection and peak detection, which involves calculations such as autocorrelation of received signals, delayed autocorrelation, and local cross-correlation. The synchronization scheme disclosed in Chinese patent application CN106789819B combines coarse and fine synchronization to achieve frame synchronization. Coarse synchronization is achieved through peak detection; however, this scheme has significant shortcomings in low signal-to-noise ratio (SNR) environments. The platform threshold in fine synchronization is highly sensitive to timing position offsets, further reducing synchronization performance in low SNR environments and consequently affecting the overall demodulation system performance. Currently, some coarse synchronization methods employ the aforementioned platform detection approach, while fine synchronization uses a normalized peak detection method based on local long preamble sequence cross-correlation (e.g., Figure 4 (As shown), however, the platform detection in the coarse synchronization of this method is easily affected by signal-to-noise ratio fluctuations, leading to missed synchronization or false synchronization. Summary of the Invention

[0004] Therefore, it is necessary to provide a frame synchronization method, apparatus, device, and medium for wireless communication systems to address the aforementioned technical problems.

[0005] A frame synchronization method for wireless communication systems, the method comprising:

[0006] The long preamble sequence of the received signal is preprocessed to obtain the preprocessed signal;

[0007] The autocorrelation of the preprocessed signal is performed, and then the square of the modulus is calculated to obtain the autocorrelation result.

[0008] The preprocessed signal is shifted and stored. The shifted output sequence and the preprocessed local long preamble sequence are cross-correlated and the magnitude squared to obtain the cross-correlation result.

[0009] Peak detection is performed based on the product of the autocorrelation result, the squared threshold of the autocorrelation modulus of the local long leader sequence, and the peak determination threshold, and the cross-correlation result. Frame synchronization is then performed based on the peak detection result.

[0010] A frame synchronization device for a wireless communication system, the device comprising:

[0011] The preprocessing module is used to preprocess the long preamble sequence of the received signal to obtain the preprocessed signal;

[0012] The autocorrelation module is used to perform autocorrelation on the preprocessed signal and then calculate the square of the modulus to obtain the autocorrelation result.

[0013] The cross-correlation module is used to shift and store the preprocessed signal, cross-correlate the shifted output sequence with the preprocessed local long preamble sequence, and then calculate the square of the modulus to obtain the cross-correlation result;

[0014] The frame synchronization module is used to perform peak detection based on the product of the autocorrelation result, the squared threshold of the autocorrelation modulus of the local long leader sequence, and the peak determination threshold, and the cross-correlation result, and to perform frame synchronization based on the peak detection result.

[0015] A computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program performing the following steps:

[0016] The long preamble sequence of the received signal is preprocessed to obtain the preprocessed signal;

[0017] The autocorrelation of the preprocessed signal is performed, and then the square of the modulus is calculated to obtain the autocorrelation result.

[0018] The preprocessed signal is shifted and stored. The shifted output sequence and the preprocessed local long preamble sequence are cross-correlated and the magnitude squared to obtain the cross-correlation result.

[0019] Peak detection is performed based on the product of the autocorrelation result, the squared threshold of the autocorrelation modulus of the local long leader sequence, and the peak determination threshold, and the cross-correlation result. Frame synchronization is then performed based on the peak detection result.

[0020] A computer-readable storage medium having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0021] The long preamble sequence of the received signal is preprocessed to obtain the preprocessed signal;

[0022] The autocorrelation of the preprocessed signal is performed, and then the square of the modulus is calculated to obtain the autocorrelation result.

[0023] The preprocessed signal is shifted and stored. The shifted output sequence and the preprocessed local long preamble sequence are cross-correlated and the magnitude squared to obtain the cross-correlation result.

[0024] Peak detection is performed based on the product of the autocorrelation result, the squared threshold of the autocorrelation modulus of the local long leader sequence, and the peak determination threshold, and the cross-correlation result. Frame synchronization is then performed based on the peak detection result.

[0025] The aforementioned frame synchronization method, apparatus, device, and medium for wireless communication systems improve synchronization accuracy and conserve algorithm resources by synchronizing a long training field after gain adjustment and stabilization. Specifically, preprocessing the long preamble sequence of the received signal and the local long preamble sequence shortens the length of periodic sequences in the signal and reduces the window width of correlation operations, thereby reducing the occurrence of spurious peaks. Peak detection is performed based on the product of the autocorrelation result, the squared autocorrelation modulus threshold of the local long preamble sequence, and the peak value determination threshold, along with the cross-correlation result. Frame synchronization is then performed based on the peak detection result, reducing computational latency and improving system demodulation efficiency. This invention can improve the frame synchronization accuracy and efficiency of wireless communication systems in low signal-to-noise ratio environments. Attached Figure Description

[0026] Figure 1 This is a flowchart illustrating a frame synchronization method for a wireless communication system in one embodiment.

[0027] Figure 2 This is a schematic diagram of a typical frame structure in one embodiment;

[0028] Figure 3 This is a flowchart illustrating the differential correlation synchronization algorithm in one embodiment;

[0029] Figure 4 This is a traditional synchronization algorithm used in the simulation comparison experiment of one embodiment;

[0030] Figure 5 This is a schematic diagram comparing the correlation peak results of the differential correlation synchronization algorithm and the traditional synchronization algorithm in one embodiment, wherein (a) is a schematic diagram of the correlation peak results using the differential correlation synchronization algorithm, and (b) is a schematic diagram of the correlation peak results using the traditional synchronization algorithm;

[0031] Figure 6 This is a structural block diagram of a frame synchronization device for a wireless communication system in one embodiment.

[0032] Figure 7This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0034] In one embodiment, such as Figure 1 As shown, a frame synchronization method for wireless communication systems is provided, including the following steps:

[0035] Step 102: Preprocess the long preamble sequence of the received signal to obtain the preprocessed signal.

[0036] The frame begins with a preamble sequence (a short training sequence and a long training sequence) used for synchronization, frequency offset correction, and channel estimation. A typical frame structure is as follows: Figure 2 As shown, in short-range wireless communication, the received signal power is usually large. Due to the adjustment of AGC (Automatic Gain Control), the signal amplitude of the short training sequence changes continuously, which affects the correlation of the signal. The method of this invention synchronizes the long training field after the hardware gain adjustment is stabilized, which can improve the synchronization reliability.

[0037] Due to the periodicity and cyclic shift of the preamble sequence, interference peaks and spurious correlation peaks are introduced. To address this issue, this invention proposes an innovative method for preprocessing the received signal. Preprocessing involves multiplying the received signal by its conjugate with the signal delayed by a factor of D to obtain a new received signal. Similarly, preprocessing is also performed on the local long preamble sequence. After this preprocessing, the length of the periodic sequence in the signal can be shortened, and the window width of the correlation operation can be reduced, thereby decreasing the occurrence of spurious peaks.

[0038] Step 104: Perform autocorrelation on the preprocessed signal and then calculate the square of the modulus to obtain the autocorrelation result.

[0039] Step 106: Shift and store the preprocessed signal, cross-correlate the shifted output sequence with the preprocessed local long preamble sequence, and then calculate the square of the modulus to obtain the cross-correlation result.

[0040] When implemented in an FPGA, the stored local long leader sequence is the conjugate of the preprocessed local long leader sequence, which can omit the first conjugation step in the calculation and reduce the calculation delay.

[0041] Step 108: Perform peak detection based on the product of the autocorrelation result, the squared threshold of the autocorrelation modulus of the local long leader sequence, and the peak determination threshold, and the cross-correlation result, and perform frame synchronization based on the peak detection result.

[0042] In the aforementioned frame synchronization method for wireless communication systems, synchronizing the long training field after gain adjustment and stabilization improves synchronization accuracy and saves algorithm resources. Specifically, preprocessing the long preamble sequence of the received signal and the local long preamble sequence shortens the length of the periodic sequence in the signal and reduces the window width of correlation operations, thereby reducing the occurrence of spurious peaks. Peak detection is performed based on the product of the autocorrelation result, the squared autocorrelation modulus threshold of the local long preamble sequence, and the peak value determination threshold, along with the cross-correlation result. Frame synchronization is then performed based on the peak detection result, reducing computational latency and improving system demodulation efficiency. This embodiment of the invention can improve the frame synchronization accuracy and efficiency of wireless communication systems in low signal-to-noise ratio environments.

[0043] In one embodiment, preprocessing the long preamble sequence of the received signal to obtain a preprocessed signal includes: multiplying the long preamble sequence of the received signal and the long preamble sequence of the received signal delayed by a preset time interval by conjugate, to obtain the preprocessed signal as follows:

[0044] r(n) = r(n) × r(nD) *

[0045] Where r(n) represents the long preamble sequence of the received signal, and r(nD) * Let r(n) be the conjugate signal after a delay of D, r(n)' be the preprocessed signal, D be the time interval, and n be the time moment.

[0046] In one embodiment, performing autocorrelation on the preprocessed signal and then taking the square of the modulus to obtain the autocorrelation result includes: performing autocorrelation on the preprocessed signal and taking the square of the modulus to obtain the autocorrelation signal as follows:

[0047]

[0048] Where M(n) is the autocorrelation result, L is the sequence window width of the correlation operation, and i is the sequence index within the correlation window.

[0049] In one embodiment, cross-correlating the shifted output sequence and the preprocessed local long preamble sequence and then calculating the square of the modulus to obtain the cross-correlation result includes: cross-correlating the shifted output sequence and the preprocessed local long preamble sequence to obtain the cross-correlation signal as follows:

[0050]

[0051] Where C(n) is the cross-correlation result.

[0052] In one embodiment, the step of obtaining the local long leader sequence autocorrelation magnitude squared threshold includes: acquiring a local long leader sequence, preprocessing the local long leader sequence, calculating the magnitude squared of the autocorrelation of the preprocessed local long leader sequence, and obtaining the local long leader sequence autocorrelation magnitude squared threshold as follows:

[0053]

[0054] Where, r ref (i)' represents the preprocessed local long leading sequence, L is the sequence window width for the correlation operation, and i is the sequence index within the correlation window. * The expression indicates conjugate processing, and P is the threshold for the squared autocorrelation modulus of the local long leader sequence. In this embodiment, the squared autocorrelation modulus of the preprocessed local long leader sequence is a constant after selection and does not need to be repeatedly calculated.

[0055] In one embodiment, peak detection based on the product of autocorrelation result, the squared autocorrelation modulus threshold of the local long leader sequence, and the peak determination threshold, and the cross-correlation result includes: obtaining a pre-set peak determination threshold; obtaining a constant value based on the product of the peak determination threshold and the squared autocorrelation modulus threshold of the local long leader sequence; and obtaining the peak detection expression based on the product of the constant value, the autocorrelation result, and the cross-correlation result:

[0056] C(n)≥M(n)×P×T

[0057] Where C(n) is the cross-correlation result, M(n) is the autocorrelation result, P is the local long leader sequence autocorrelation magnitude squared threshold, and T is the peak determination threshold; peak detection is performed according to the peak detection expression.

[0058] In this embodiment, peak detection timing synchronization generally involves first normalizing the autocorrelation and cross-correlation and then comparing them with the threshold. This is implemented in an FPGA. The division operation is resource-intensive and has a long computation delay. This invention converts the division operation into a multiplication operation. Once the threshold is selected, P×T is also a constant, which reduces one division operation and greatly reduces the resources required to implement the entire synchronization algorithm.

[0059] In one embodiment, frame synchronization based on peak detection results includes: if the current cross-correlation result is greater than or equal to the product of a constant value and an autocorrelation result, then the position corresponding to the current autocorrelation result is taken as the starting point of the signal frame for frame synchronization.

[0060] In one specific embodiment, such as Figure 3The diagram illustrates a flowchart of a differential correlation synchronization algorithm. Before performing the correlation operation, the signal delay D is multiplied by the signal conjugate to obtain the processed sequence. The local sequence also needs to undergo the same operation to form a new local sequence. This algorithm is defined as the differential correlation synchronization algorithm. The value of D and L can be adjusted. The algorithm employs... Figure 4 A simulation comparison experiment was conducted using the traditional synchronization algorithm shown. Figure 4 In the process, coarse synchronization uses platform detection, while fine synchronization uses a peak detection method based on the normalization of local sequence cross-correlation.

[0061] Specifically, in the MATLAB simulation, this paper selects D as 16 and L as 48, such as... Figure 5 The diagram shows a comparison of the correlation peak results between the differential correlation synchronization algorithm and the traditional synchronization algorithm. (a) shows the correlation peak results using the differential correlation synchronization algorithm, and (b) shows the correlation peak results using the traditional synchronization algorithm. It can be seen that the positions of the correlation peaks are basically consistent in both diagrams. The points (305,1) and (369,1) are the correlation peak positions of long training sequences, with a difference of 64. Other peaks are spurious peaks. A comparison of the two diagrams shows that the peak values ​​of other spurious peaks in the differential correlation synchronization algorithm of this invention are lower than those in existing correlation synchronization algorithms.

[0062] MATLAB simulations show that, ideally, the normalized value of the correlation peak is 1, i.e. Figure 3 In the equation A = B, in practice, due to factors such as channel and frequency offset, the correlation peak is less than 1. Therefore, the threshold can be adjusted so that A > 0.8 * B, meaning the peak value is greater than 0.8. Furthermore, this threshold can be reflected in the local autocorrelation modulus squared threshold, i.e., the local sequence autocorrelation modulus squared multiplied by the threshold. After selecting the sequence and quantization bit width, the modulus squared of the local autocorrelation is a constant, and multiplying it by the threshold also results in a constant. Therefore, it's unnecessary to add floating-point multiplication operations for this threshold during FPGA implementation; it can simply be filled in as a constant.

[0063] It should be understood that, although Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0064] In one embodiment, such as Figure 6 As shown, a frame synchronization device for a wireless communication system is provided, comprising:

[0065] The preprocessing module 602 is used to preprocess the long preamble sequence of the received signal to obtain a preprocessed signal;

[0066] The autocorrelation module 604 is used to perform autocorrelation on the preprocessed signal and then calculate the square of the modulus to obtain the autocorrelation result.

[0067] The cross-correlation module 606 is used to shift and store the preprocessed signal, cross-correlate the shifted output sequence with the preprocessed local long preamble sequence, and then calculate the square of the modulus to obtain the cross-correlation result;

[0068] The frame synchronization module 608 is used to perform peak detection based on the product of the autocorrelation result, the squared threshold of the autocorrelation modulus of the local long leader sequence, and the peak determination threshold, and the cross-correlation result, and to perform frame synchronization based on the peak detection result.

[0069] In one embodiment, the receiver further performs conjugate multiplication of the long preamble sequence of the received signal and the long preamble sequence of the received signal delayed by a preset time interval to obtain the preprocessed signal as follows:

[0070] r(n)′=r(n)×r(nD) *

[0071] Where r(n) represents the long preamble sequence of the received signal, and r(nD) * Let r(n) be the conjugate signal after a delay of D, r(n)' be the preprocessed signal, D be the time interval, and n be the time moment.

[0072] In one embodiment, the preprocessed signal is further subjected to autocorrelation modulus square calculation to obtain the autocorrelation signal as follows:

[0073]

[0074] Where M(n) is the autocorrelation result, L is the sequence window width of the correlation operation, and i is the sequence index within the correlation window.

[0075] In one embodiment, the shifted output sequence and the preprocessed local long preamble sequence are further cross-correlated to obtain the cross-correlation signal as follows:

[0076]

[0077] Where C(n) is the cross-correlation result.

[0078] In one embodiment, the method further includes obtaining a local long leader sequence, preprocessing the local long leader sequence, and calculating the squared modulus of the autocorrelation of the preprocessed local long leader sequence to obtain the threshold value of the squared modulus of the autocorrelation of the local long leader sequence.

[0079]

[0080] Where, r ref (i)' represents the preprocessed local long leading sequence, L is the sequence window width for the correlation operation, and i is the sequence index within the correlation window. * This indicates conjugate processing, where P is the local long leader sequence autocorrelation modulus squared threshold.

[0081] In one embodiment, it is further used to obtain a pre-set peak determination threshold; based on the product of the peak determination threshold and the squared autocorrelation modulus threshold of the local long leader sequence, a constant value is obtained; based on the product of the constant value and the autocorrelation result and the cross-correlation result, the peak detection expression is obtained as follows:

[0082] C(n)≥M(n)×P×T

[0083] Where C(n) is the cross-correlation result, M(n) is the autocorrelation result, P is the local long leader sequence autocorrelation magnitude squared threshold, and T is the peak determination threshold; peak detection is performed according to the peak detection expression.

[0084] In one embodiment, if the current cross-correlation result is greater than or equal to the product of the constant value and the autocorrelation result, then the position corresponding to the current autocorrelation result is taken as the starting point of the signal frame for frame synchronization.

[0085] Specific limitations regarding the frame synchronization device for wireless communication systems can be found in the limitations of the frame synchronization method for wireless communication systems described above, and will not be repeated here. Each module in the aforementioned frame synchronization device for wireless communication systems can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in hardware or independently of the processor in a computer device, or stored in software in the memory of a computer device, so that the processor can call and execute the operations corresponding to each module.

[0086] In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be as follows: Figure 7As shown, the computer device includes a processor, memory, network interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The network interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements a frame synchronization method for wireless communication systems. The display screen can be a liquid crystal display (LCD) or an e-ink display. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the computer device casing, or an external keyboard, touchpad, or mouse.

[0087] Those skilled in the art will understand that Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present invention and does not constitute a limitation on the computer device to which the present invention is applied. A specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0088] In one embodiment, a computer device is provided, including a memory and a processor, the memory storing a computer program, the processor executing the computer program to implement the steps of the method described above.

[0089] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described above.

[0090] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided by this invention can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0091] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0092] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A frame synchronization method for wireless communication systems, characterized in that, The method includes: The long preamble sequence of the received signal is preprocessed to obtain the preprocessed signal; The autocorrelation of the preprocessed signal is performed, and then the square of the modulus is calculated to obtain the autocorrelation result. The preprocessed signal is shifted and stored. The shifted output sequence and the preprocessed local long preamble sequence are cross-correlated and the magnitude squared to obtain the cross-correlation result. Peak detection is performed based on the product of the autocorrelation result, the squared autocorrelation modulus threshold of the local long leader sequence, and the peak determination threshold, and the cross-correlation result; and frame synchronization is performed based on the peak detection result. Peak detection is performed by multiplying the autocorrelation result, the squared autocorrelation modulus threshold of the local long leader sequence, and the peak determination threshold with the cross-correlation result, including: Obtain the pre-set peak value threshold; A constant value is obtained by multiplying the peak determination threshold and the squared autocorrelation modulus threshold of the local long leader sequence. The peak detection expression is then derived from the product of this constant value, the autocorrelation result, and the cross-correlation result: in, For cross-correlation results, It is an autocorrelation result. The threshold for the squared magnitude of the autocorrelation of the local long leader sequence. The threshold for determining the peak value; Peak detection is performed according to the peak detection expression.

2. The method according to claim 1, characterized in that, The preprocessing of the long preamble sequence of the received signal to obtain the preprocessed signal includes: The preprocessed signal is obtained by conjugating the long preamble sequence of the received signal and the long preamble sequence of the received signal after a preset time interval: in, This represents a long preamble sequence of the received signal. for The conjugate signal after delay D. The preprocessed signal is the long preamble sequence of the received signal, where D is the time interval. It is a moment.

3. The method according to claim 2, characterized in that, The autocorrelation of the preprocessed signal is then calculated, followed by taking the square of the modulus. The autocorrelation results include: The autocorrelation of the preprocessed signal is calculated by taking the square of its modulus, resulting in the autocorrelation signal: in, It is an autocorrelation result. It is the width of the sequence window for the related operations. It is the sequence index within the relevant window.

4. The method according to claim 3, characterized in that, The shifted output sequence and the preprocessed local long leader sequence are cross-correlated, and the modulus squared is calculated to obtain the cross-correlation results, including: The shifted output sequence and the preprocessed local long preamble sequence are cross-correlated to obtain the cross-correlation signal: in, The results are cross-correlation results.

5. The method according to claim 1, characterized in that, The steps for obtaining the squared autocorrelation modulus threshold of the local long leader sequence include: Obtain the local long leader sequence, preprocess the local long leader sequence, and calculate the squared modulus of the autocorrelation of the preprocessed local long leader sequence to obtain the threshold for the squared modulus of the local long leader sequence: in, It is a preprocessed local long leader sequence. It is the width of the sequence window for the related operations. It is the sequence index within the relevant window. Indicates conjugate processing. The threshold value is the squared autocorrelation modulus of the local long leader sequence.

6. The method according to claim 1, characterized in that, Frame synchronization based on peak detection results includes: If the current cross-correlation result is greater than or equal to the product of the constant value and the autocorrelation result, then the position corresponding to the current autocorrelation result is taken as the starting point of the signal frame for frame synchronization.

7. A frame synchronization device for a wireless communication system applied to the method described in any one of claims 1-6, characterized in that, The device includes: The preprocessing module is used to preprocess the long preamble sequence of the received signal to obtain the preprocessed signal; The autocorrelation module is used to perform autocorrelation on the preprocessed signal and then calculate the square of the modulus to obtain the autocorrelation result. The cross-correlation module is used to shift and store the preprocessed signal, cross-correlate the shifted output sequence with the preprocessed local long preamble sequence, and then calculate the square of the modulus to obtain the cross-correlation result; The frame synchronization module is used to perform peak detection based on the product of the autocorrelation result, the squared threshold of the autocorrelation modulus of the local long leader sequence, and the peak determination threshold, and the cross-correlation result, and to perform frame synchronization based on the peak detection result.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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