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

Abstract

The invention relates to a frame synchronization method, device and equipment for a wireless communication system and a medium. The method comprises the following steps: preprocessing a long leader sequence of a received signal to obtain a preprocessed signal; carrying out self-correlation on the preprocessed signal and then solving modular square to obtain a self-correlation result; performing shift storage on the pre-processed signal, performing cross-correlation on the shifted output sequence and the pre-processed local long leader sequence, and then calculating modular square to obtain a cross-correlation result; and carrying out peak detection according to a product of an autocorrelation result, an autocorrelation modular square threshold value of the local long leader sequence and a peak judgment threshold value and the cross-correlation result, and carrying out frame synchronization according to a peak detection result. By adopting the method, the frame synchronization precision and efficiency of the wireless communication system in a low signal-to-noise ratio environment can be improved.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to a frame synchronization method, device, equipment and medium for a wireless communication system. Background Art

[0002] With the rapid development and widespread application of communication technology, wireless local area network (WLAN) has become an indispensable part of people's daily life and work. In wireless local area network, IEEE 802.11 standard, as the mainstream standard, has long been one of the hot research areas of companies and universities. With the continuous improvement of the performance requirements of communication systems, the importance of physical layer frame detection synchronization in wireless communication reception has become increasingly prominent. As the first step of the physical layer in the wireless communication reception process, frame detection synchronization directly affects the reception performance of the entire system. The synchronization algorithm can be roughly divided into two categories: time domain synchronization and frequency domain synchronization. Among them, time domain synchronization is usually implemented based on correlation operations. Its core idea is to detect and synchronize frames through the correlation between signals. With the continuous improvement of the synchronization accuracy requirements, various synchronization algorithms based on correlation operations have emerged and have been continuously improved and optimized.

[0003] In the existing wireless LAN synchronization technology, the timing synchronization of frames is often achieved through platform detection and peak detection composed of operations such as autocorrelation, delayed autocorrelation, and local cross-correlation of the received signal. The synchronization scheme disclosed in Chinese Patent Application No. CN106789819B achieves frame synchronization by combining coarse synchronization and fine synchronization. Coarse synchronization is achieved through peak judgment. However, this scheme has obvious shortcomings in low signal-to-noise ratio environments. The platform threshold in fine synchronization is very sensitive to the timing position offset, which further reduces the synchronization performance in a low signal-to-noise ratio environment, and further affects the performance of the entire demodulation system. At present, there is also platform detection using the above method for coarse synchronization, and fine synchronization uses a normalized peak detection method of local long preamble sequence cross-correlation (such as Figure 4 However, the platform detection in the coarse synchronization of this method is easily affected by the fluctuation of the signal-to-noise ratio, resulting in missed synchronization or false synchronization. Summary of the invention

[0004] Based on this, it is necessary to provide a frame synchronization method, device, equipment and medium for a wireless communication system to address the above technical problems.

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

[0006] Preprocessing the long leading sequence of the received signal to obtain a preprocessed signal;

[0007] Autocorrelation is performed on the preprocessed signal and then the modulus square is calculated to obtain the autocorrelation result;

[0008] The preprocessed signal is shifted and stored, and the shifted output sequence and the preprocessed local long leading sequence are cross-correlated and then squared to obtain a cross-correlation result;

[0009] Peak detection is performed based on the product of the autocorrelation result, the local long preamble sequence autocorrelation modulus square threshold and the peak decision threshold and the cross-correlation result, and frame synchronization is performed based on the peak detection result.

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

[0011] A preprocessing module, used for preprocessing the long leading sequence of the received signal to obtain a preprocessed signal;

[0012] An autocorrelation module is used to perform autocorrelation on the preprocessed signal and then calculate the modulus square to obtain an autocorrelation result;

[0013] A cross-correlation module is used to shift and store the pre-processed signal, cross-correlate the shifted output sequence with the pre-processed local long leading sequence, and then calculate the square of the modulus to obtain a cross-correlation result;

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

[0015] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0016] Preprocessing the long leading sequence of the received signal to obtain a preprocessed signal;

[0017] Autocorrelation is performed on the preprocessed signal and then the modulus square is calculated to obtain the autocorrelation result;

[0018] The preprocessed signal is shifted and stored, and the shifted output sequence and the preprocessed local long leading sequence are cross-correlated and then squared to obtain a cross-correlation result;

[0019] Peak detection is performed based on the product of the autocorrelation result, the local long preamble sequence autocorrelation modulus square threshold and the peak decision threshold and the cross-correlation result, and frame synchronization is performed based on the peak detection result.

[0020] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the following steps:

[0021] Preprocessing the long leading sequence of the received signal to obtain a preprocessed signal;

[0022] Autocorrelation is performed on the preprocessed signal and then the modulus square is calculated to obtain the autocorrelation result;

[0023] The preprocessed signal is shifted and stored, and the shifted output sequence and the preprocessed local long leading sequence are cross-correlated and then squared to obtain a cross-correlation result;

[0024] Peak detection is performed based on the product of the autocorrelation result, the local long preamble sequence autocorrelation modulus square threshold and the peak decision threshold and the cross-correlation result, and frame synchronization is performed based on the peak detection result.

[0025] The above-mentioned frame synchronization method, device, equipment and medium for wireless communication systems can not only improve the synchronization accuracy but also save algorithm resources by synchronizing the long training field after the gain adjustment is stabilized. Specifically, the long preamble sequence of the received signal and the local long preamble sequence are preprocessed, which can shorten the length of the periodic sequence in the signal and shorten the window width of the correlation operation, thereby reducing the occurrence of pseudo peaks. Peak detection is performed based on the product of the autocorrelation result, the local long preamble sequence autocorrelation modulus square threshold and the peak judgment threshold and the cross-correlation result, and frame synchronization is performed based on the peak detection result, which can reduce the calculation delay and improve the system demodulation efficiency. The embodiment of the present invention can improve the frame synchronization accuracy and efficiency of the wireless communication system in a low signal-to-noise ratio environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of a flow chart of a frame synchronization method for a wireless communication system in one embodiment;

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

[0028] Figure 3 Schematic diagram of a flow chart of a differential correlation synchronization algorithm in one embodiment;

[0029] Figure 4 A traditional synchronization algorithm used in a simulation comparison experiment in an embodiment;

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

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

[0032] Figure 7FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

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

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

[0036] The beginning of the frame has a preamble sequence (short training sequence and long training sequence) for synchronization, frequency offset correction and channel estimation. The typical frame structure is as follows: Figure 2 As shown, in the case of short-distance wireless communication, the received signal power is usually large, and the signal amplitude of the short training sequence is constantly changing due to the adjustment of AGC (Automatic Gain Control), thereby affecting the correlation of the signal. The method of the present 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 pseudo-correlation peaks are introduced. To solve this problem, the present invention proposes an innovative way to preprocess the received signal. Preprocessing refers to conjugating and multiplying the received signal with its delayed signal D to obtain a new received signal. Similarly, the local long preamble sequence is also preprocessed. After the above preprocessing, the length of the periodic sequence in the signal can be shortened, the window width of the correlation operation can be shortened, and the occurrence of pseudo-peaks can be reduced.

[0038] Step 104, autocorrelate the preprocessed signal and then square its modulus to obtain an 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 modulus square to obtain a cross-correlation result.

[0040] When implemented in FPGA, the stored local long preamble sequence is the conjugate of the preprocessed local long preamble sequence, so the step of pre-conjugation in the calculation can be omitted, thereby reducing the calculation delay.

[0041] Step 108, performing peak detection based on the product of the autocorrelation result, the local long preamble sequence autocorrelation modulus square threshold and the peak decision threshold and the cross-correlation result, and performing frame synchronization based on the peak detection result.

[0042] In the above-mentioned frame synchronization method for wireless communication systems, by synchronizing the long training field after the gain adjustment is stabilized, it is possible to improve the synchronization accuracy and save algorithm resources. Specifically, the long preamble sequence of the received signal and the local long preamble sequence are preprocessed, which can shorten the length of the periodic sequence in the signal and shorten the window width of the correlation operation, thereby reducing the occurrence of pseudo peaks. Peak detection is performed based on the product of the autocorrelation result, the local long preamble sequence autocorrelation modulus square threshold and the peak judgment threshold and the cross-correlation result, and frame synchronization is performed based on the peak detection result, which can reduce the calculation delay and improve the system demodulation efficiency. The embodiment of the present invention can improve the frame synchronization accuracy and efficiency of the wireless communication system in a low signal-to-noise ratio environment.

[0043] In one embodiment, the preprocessing of the long preamble sequence of the received signal to obtain the preprocessed signal includes: conjugating and multiplying 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:

[0044] r(n)=r(n)×r(nD) *

[0045] Among them, r(n) represents the long preamble sequence of the received signal, r(nD) * is the conjugate signal after r(n) is delayed by D, r(n)' is the preprocessed signal, D is the time interval, and n is the time.

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

[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 with the pre-processed local long preamble sequence and then calculating the modulus square to obtain a cross-correlation result includes: cross-correlating the shifted output sequence with the pre-processed local long preamble sequence to obtain a cross-correlation signal:

[0050]

[0051] Among them, C(n) is the cross-correlation result.

[0052] In one embodiment, the step of obtaining the local long preamble sequence autocorrelation modulus square threshold comprises: obtaining a local long preamble sequence, preprocessing the local long preamble sequence, calculating the modulus square of the preprocessed local long preamble sequence autocorrelation, and obtaining the local long preamble sequence autocorrelation modulus square threshold as:

[0053]

[0054] Among them, r ref (i)' is the preprocessed local long leading sequence, L is the sequence window width of the correlation operation, i is the sequence index in the correlation window, (·) * represents conjugate processing, and P is the local long preamble sequence autocorrelation modulus square threshold. In this embodiment, the local long preamble sequence autocorrelation modulus square after preprocessing is a constant after selection, and does not need to be repeatedly calculated.

[0055] In one embodiment, performing peak detection according to the product of the autocorrelation result, the local long preamble sequence autocorrelation modulus square threshold and the peak decision threshold and the cross-correlation result includes: obtaining a preset peak decision threshold; obtaining a constant value according to the product of the peak decision threshold and the local long preamble sequence autocorrelation modulus square threshold, and obtaining a peak detection expression according to the product of the constant value and the autocorrelation result and the cross-correlation result:

[0056] C(n)≥M(n)×P×T

[0057] Wherein, C(n) is the cross-correlation result, M(n) is the autocorrelation result, P is the local long preamble sequence autocorrelation modulus square 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 is performed. Generally, the autocorrelation and cross-correlation are normalized and then compared with the threshold. It is implemented in FPGA. The division operation is resource-intensive and the calculation delay is long. The present invention converts the division operation into a multiplication operation. After the threshold is selected, P×T is also a constant, which can reduce one division operation, greatly reducing the resources occupied by the entire synchronization algorithm.

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

[0060] In a specific embodiment, Figure 3As shown in FIG. 1 , a flow chart of a differential correlation synchronization algorithm is provided. 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 a differential correlation synchronization algorithm. The size of D can be adjusted, and L can also be adjusted. Figure 4 The traditional synchronization algorithm shown in the simulation comparison experiment is Figure 4 In the coarse synchronization, platform detection is used, and the fine synchronization is performed by the normalized peak detection method of the 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 figure shows a comparison diagram of the correlation peak results of the differential correlation synchronization algorithm and the traditional synchronization algorithm, where (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. It can be seen that in the two figures, the positions of the correlation peaks are basically the same, and the two points (305,1) and (369,1) are the positions of the correlation peaks of the long training sequence, with an interval difference of 64. The other peaks are all pseudo peaks. By comparing the two figures, it can be seen that the peak values ​​of the other pseudo peaks of the differential correlation synchronization algorithm of the present invention are lower than those of the existing correlation synchronization algorithm.

[0062] From the MATLAB simulation, we know that, ideally, the normalized value of the correlation peak is 1, that is, Figure 3 In the example, A=B. In practice, due to the influence of the channel and frequency offset, the correlation peak is less than 1. Then the threshold can be adjusted, A>0.8*B, that is, the peak value is greater than 0.8. Moreover, this threshold can be reflected in the local autocorrelation modulus square threshold, that is, the local sequence autocorrelation modulus square multiplied by the threshold. After the sequence and quantization bit width are selected, the local autocorrelation modulus square is a constant, and it is still a constant after multiplying the threshold. Therefore, there is no need to add the floating-point multiplication operation of this threshold when implementing it in the FPGA, but it can be filled in as a constant.

[0063] It should be understood that although Figure 1 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed 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 part of the sub-steps or stages of other steps.

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

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

[0066] An autocorrelation module 604 is used to perform autocorrelation on the preprocessed signal and then calculate the modulus square to obtain an autocorrelation result;

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

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

[0069] In one of the embodiments, it is also used to conjugate and multiply 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 a preprocessed signal:

[0070] r(n)′=r(n)×r(nD) *

[0071] Among them, r(n) represents the long preamble sequence of the received signal, r(nD) * is the conjugate signal after r(n) is delayed by D, r(n)' is the preprocessed signal, D is the time interval, and n is the time.

[0072] In one embodiment, it is also used to perform autocorrelation modulus square on the preprocessed signal to obtain an autocorrelation signal:

[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 of the embodiments, the shifted output sequence and the preprocessed local long preamble sequence are cross-correlated to obtain a cross-correlation signal:

[0076]

[0077] Among them, C(n) is the cross-correlation result.

[0078] In one of the embodiments, it is also used to obtain a local long preamble sequence, preprocess the local long preamble sequence, calculate the modulus square of the autocorrelation of the preprocessed local long preamble sequence, and obtain the local long preamble sequence autocorrelation modulus square threshold as:

[0079]

[0080] Among them, r ref (i)' is the preprocessed local long leading sequence, L is the sequence window width of the correlation operation, i is the sequence index in the correlation window, (·) * represents conjugate processing, and P is the local long preamble sequence autocorrelation modulus square threshold.

[0081] In one of the embodiments, it is also used to obtain a preset peak decision threshold; according to the product of the peak decision threshold and the local long preamble sequence autocorrelation modulus square threshold, a constant value is obtained, and according to the product of the constant value and the autocorrelation result and the cross-correlation result, a peak detection expression is obtained:

[0082] C(n)≥M(n)×P×T

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

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

[0085] For the specific definition of the frame synchronization device for wireless communication systems, please refer to the definition of the frame synchronization method for wireless communication systems mentioned above, which will not be repeated here. Each module in the above-mentioned frame synchronization device for wireless communication systems can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0086] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Figure 7As shown. The computer device includes a processor, a memory, a network interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a frame synchronization method for a wireless communication system is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covered on the display screen, or a key, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

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

[0088] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the method in the above embodiment when executing the computer program.

[0089] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method in the above embodiment are implemented.

[0090] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided by the present 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. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0091] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, 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 above-mentioned embodiments only express several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A frame synchronization method for a wireless communication system, characterized in that: The method comprises: Preprocessing the long leading sequence of the received signal to obtain a preprocessed signal; Autocorrelation is performed on the preprocessed signal and then the modulus square is calculated to obtain the autocorrelation result; The preprocessed signal is shifted and stored, and the shifted output sequence and the preprocessed local long leading sequence are cross-correlated and then squared to obtain a cross-correlation result; Peak detection is performed based on the product of the autocorrelation result, the local long preamble sequence autocorrelation modulus square threshold and the peak decision threshold and the cross-correlation result, and frame synchronization is performed based on the peak detection result.

2. The method according to claim 1, characterized in that The step of preprocessing the long leading sequence of the received signal to obtain the preprocessed signal comprises: The long preamble sequence of the received signal is conjugate-multiplied with the long preamble sequence of the received signal delayed by a preset time interval to obtain the preprocessed signal: r(n)’=r(n)×r(n-D) * Among them, r(n) represents the long preamble sequence of the received signal, r(nD) * is the conjugate signal after r(n) is delayed by D, r(n)' is the preprocessed signal, D is the time interval, and n is the moment.

3. The method according to claim 2, characterized in that Autocorrelation of the preprocessed signal is performed and then the modulus square is calculated to obtain the autocorrelation results including: The preprocessed signal is autocorrelated and squared to obtain the autocorrelation signal: 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.

4. The method according to claim 3, characterized in that The shifted output sequence and the preprocessed local long leading sequence are cross-correlated and then modulo squared to obtain the cross-correlation results including: The shifted output sequence is cross-correlated with the pre-processed local long preamble sequence, and the cross-correlation signal is obtained as follows: Among them, C(n) is the cross-correlation result.

5. The method according to claim 1, characterized in that The step of obtaining the local long preamble sequence autocorrelation modulus square threshold comprises: A local long preamble sequence is obtained, the local long preamble sequence is preprocessed, and the modulus square of the autocorrelation of the preprocessed local long preamble sequence is calculated to obtain the modulus square threshold of the autocorrelation modulus of the local long preamble sequence: Among them, r ref (i)' is the preprocessed local long leading sequence, L is the sequence window width of the correlation operation, i is the sequence index in the correlation window, (·) * represents conjugate processing, and P is the local long preamble sequence autocorrelation modulus square threshold.

6. The method according to claim 1, characterized in that Performing peak detection according to the product of the autocorrelation result, the local long preamble sequence autocorrelation modulus square threshold and the peak determination threshold and the cross-correlation result includes: Get the preset peak value determination threshold; According to the product of the peak decision threshold and the local long preamble sequence autocorrelation modulus square threshold, a constant value is obtained, and according to the product of the constant value and the autocorrelation result and the cross-correlation result, a peak detection expression is obtained: C(n)≥M(n)×P×T Wherein, C(n) is the cross-correlation result, M(n) is the autocorrelation result, P is the local long preamble sequence autocorrelation modulus square threshold, and T is the peak determination threshold; Peak detection is performed according to the peak detection expression.

7. The method according to claim 6, 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, the position corresponding to the current autocorrelation result is used as the starting point of the signal frame to perform frame synchronization.

8. A frame synchronization device for a wireless communication system, characterized in that: The device comprises: A preprocessing module, used for preprocessing the long leading sequence of the received signal to obtain a preprocessed signal; An autocorrelation module is used to perform autocorrelation on the preprocessed signal and then calculate the modulus square to obtain an autocorrelation result; A cross-correlation module is used to shift and store the pre-processed signal, cross-correlate the shifted output sequence with the pre-processed local long leading sequence, and then calculate the square of the modulus to obtain a cross-correlation result; The frame synchronization module is used to perform peak detection based on the product of the autocorrelation result, the local long leading sequence autocorrelation modulus square threshold and the peak decision threshold and the cross-correlation result, and perform frame synchronization based on the peak detection result.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

Images