A Highly Efficient Method for Capturing BOC Signals

Abstract

The present application relates to a highly efficient BOC signal capture method. The method comprises: resampling the baseband data of the BOC signal to obtain the resampled baseband data; performing phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain the baseband signal after phase rotation; using the baseband signal after phase rotation to calculate all search grids within a preset code phase search grid range to obtain the multi-phase component correlation values ​​of all search grids; performing correlation value calculation within a preset Doppler search grid range based on the multi-phase component correlation values ​​of all search grids to obtain the correlation values ​​corresponding to all search grids; and performing capture judgment on the BOC signal to be captured based on the correlation values ​​corresponding to all search grids. The present method can improve the capture and detection efficiency of the BOC signal.

Description

Technical Field

[0001] The invention relates to the technical field of satellite navigation, and in particular to a high-efficiency BOC signal capturing method. Background Art

[0002] With the development of satellite navigation technology, in order to make better use of precious frequency resources, the Global Navigation Satellite System (GNSS) has adopted a variety of parameter binary offset carrier (BOC) modulation technology. Compared with the binary phase shift keying (BPSK) modulation technology used in traditional navigation signals, the BOC modulation technology adds square wave subcarrier modulation to the spread spectrum code, moves the signal spectrum to both sides of the center frequency, and realizes the spectrum separation between different signals.

[0003] However, due to the existence of zero points in the correlation peak of the BOC signal, in order to reduce the signal-to-noise ratio loss of the correlation value, the traditional matched filter capture algorithm needs to use a smaller code phase search interval, which results in high computational complexity and low detection efficiency when using the traditional matched filter capture algorithm for BOC modulation. Summary of the invention

[0004] Based on this, it is necessary to provide a high-efficiency BOC signal capture method that can improve the BOC signal capture and detection efficiency in response to the above technical problems.

[0005] A highly efficient BOC signal capture method, the method comprising:

[0006] Obtain the BOC signal to be captured;

[0007] Resampling the baseband data of the BOC signal to obtain resampled baseband data;

[0008] Performing phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a baseband signal after phase rotation;

[0009] Utilizing the phase-rotated baseband signal to calculate all search squares within a preset code phase search square range, the multiphase component correlation values ​​of all search squares are obtained;

[0010] According to the multiphase component correlation values ​​of all search grids, correlation value calculation is performed within a preset Doppler search grid range to obtain correlation values ​​corresponding to all search grids;

[0011] The capture decision of the BOC signal to be captured is made according to the correlation values ​​corresponding to all the search grids.

[0012] In one of the embodiments, the sampling rate of the resampled baseband data is a multiple of the bit rate of the BOC signal.

[0013] In one embodiment, performing phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a phase-rotated baseband signal includes:

[0014] The resampled baseband data is phase rotated according to the Doppler frequency search interval, and the baseband signal after phase rotation is obtained as:

[0015] s′ v [k] = s′[k] exp{-j2πvf Δ kT′ s}

[0016] Among them, s′ v [k] represents the baseband signal after phase rotation, s′[k] represents the resampled baseband data, and f Δ is the Doppler frequency search interval, v represents the sequence number of the Doppler search grid, T′ s It represents the sampling period of the resampled baseband data, j is the imaginary unit, and k represents the data sequence number.

[0017] In one embodiment, all search squares within a preset code phase search square range are calculated using the phase-rotated baseband signal to obtain multiphase component correlation values ​​of all search squares, including:

[0018] The code phase search grid range is predefined as 0≤u≤U; wherein u represents the sequence number of the code phase search grid, and U represents the number of the code phase search grid;

[0019] The phase-rotated baseband signal is used to calculate all search squares within the preset code phase search square range, and the multiphase component correlation values ​​of all search squares are obtained as follows:

[0020]

[0021] Where P represents the number of phases in the search grid, p represents the phase sequence number of the search grid, and c n [k] represents the spreading code c n The kth chip of c / T′ s represents the coherent integration time T c The corresponding number of data points.

[0022] In one embodiment, the number of phases in the search grid is the same as a multiple of the code rate.

[0023] In one embodiment, correlation values ​​are calculated within a preset Doppler search grid range according to the multiphase component correlation values ​​of all search grids to obtain correlation values ​​corresponding to all search grids, including:

[0024] The preset Doppler search grid range is -V≤v≤V;

[0025] The correlation values ​​of the multiphase components of all search grids are calculated within the preset Doppler search grid range according to the correlation values ​​of the multiphase components of all search grids. The correlation values ​​corresponding to all search grids are obtained as follows:

[0026]

[0027] Wherein, i represents the serial number of the correlation value, and V represents the range of the Doppler search grid.

[0028] In one embodiment, g[pi] represents the sign of the combination of multi-phase component related values, and the specific values ​​are as follows:

[0029]

[0030] In one embodiment, performing a capture decision on a BOC signal to be captured according to the correlation values ​​corresponding to all search grids includes:

[0031] The detection statistic is calculated based on the correlation values ​​of all search squares, and is compared with the preset capture threshold. If the detection statistic is greater than or equal to the capture threshold, it means that the BOC signal is captured. If the detection statistic is greater than or equal to the capture threshold, it means that the BOC signal is not captured.

[0032] In one embodiment, the detection statistic is calculated based on the correlation values ​​of all search squares, including:

[0033] The detection statistic is calculated based on the correlation values ​​of all search squares: Wherein, L represents the number of post-accumulations.

[0034] A high-efficiency BOC signal acquisition device, the device comprising:

[0035] The resampling module is used to obtain the BOC signal to be captured; resample the baseband data of the BOC signal to obtain resampled baseband data;

[0036] A phase rotation module, used for performing phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a baseband signal after phase rotation;

[0037] A multiphase component correlation value calculation module is used to calculate all search squares within a preset code phase search square range using the phase-rotated baseband signal to obtain multiphase component correlation values ​​of all search squares;

[0038] A correlation value calculation module is used to calculate the correlation value within a preset Doppler search grid range according to the multi-phase component correlation values ​​of all search grids to obtain the correlation values ​​corresponding to all search grids;

[0039] The capture decision module is used to make a capture decision on the BOC signal to be captured according to the correlation values ​​corresponding to all the search grids.

[0040] 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:

[0041] Obtain the BOC signal to be captured;

[0042] Resampling the baseband data of the BOC signal to obtain resampled baseband data;

[0043] Performing phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a baseband signal after phase rotation;

[0044] Utilizing the phase-rotated baseband signal to calculate all search squares within a preset code phase search square range, the multiphase component correlation values ​​of all search squares are obtained;

[0045] According to the multiphase component correlation values ​​of all search grids, correlation value calculation is performed within a preset Doppler search grid range to obtain correlation values ​​corresponding to all search grids;

[0046] The capture decision of the BOC signal to be captured is made according to the correlation values ​​corresponding to all the search grids.

[0047] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the following steps:

[0048] Obtain the BOC signal to be captured;

[0049] Resampling the baseband data of the BOC signal to obtain resampled baseband data;

[0050] Performing phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a baseband signal after phase rotation;

[0051] Utilizing the phase-rotated baseband signal to calculate all search squares within a preset code phase search square range, the multiphase component correlation values ​​of all search squares are obtained;

[0052] According to the multiphase component correlation values ​​of all search grids, correlation value calculation is performed within a preset Doppler search grid range to obtain correlation values ​​corresponding to all search grids;

[0053] The capture decision of the BOC signal to be captured is made according to the correlation values ​​corresponding to all the search grids.

[0054] The above-mentioned highly efficient BOC signal capture method, device, computer equipment and storage medium first resamples the baseband data of the BOC signal so that the sampling rate of the resampled baseband data is equal to a multiple of the code rate. Since the sampling rate of the resampled baseband data is exactly a multiple of the code rate, the baseband data can be subjected to multi-phase decomposition of multiple extraction, and the correlation value is decomposed into multi-phase component correlation values ​​of the same phase as the multiple. When the code phase search interval is 1 / multiple code chip, the multi-phase component correlation values ​​corresponding to different search code phases can be efficiently reused, thereby reducing the complexity of correlation value calculation, thereby improving the BOC signal capture and detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 A schematic diagram of a flow chart of a highly efficient BOC signal acquisition method in an embodiment;

[0056] Figure 2 A block diagram of an implementation of calculating correlation values ​​of multi-phase components of different search code phases for a BOC (1, 1) signal in one embodiment;

[0057] Figure 3 A block diagram of an implementation of calculating a search grid correlation value based on multi-phase component correlation values ​​of a BOC (1, 1) signal in one embodiment;

[0058] Figure 4 is a structural block diagram of a highly efficient BOC signal acquisition device in one embodiment;

[0059] Figure 5 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application 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 application and are not used to limit the present application.

[0061] In one embodiment, Figure 1 As shown, a high-efficiency BOC signal capture method is provided, comprising the following steps:

[0062] Step 102, obtaining a BOC signal to be captured; resampling the baseband data of the BOC signal to obtain resampled baseband data.

[0063] The baseband data s[k] of the BOC(m,n) signal is resampled so that the sampling rate of the resampled baseband data s′[k] is 1 / T′ s It is equal to Pn×1.023MHz, where P=4m / n. Since the sampling rate of the resampled baseband data is exactly P times the bit rate, the baseband data can be subjected to multi-phase decomposition with P times extraction.

[0064] Step 104 , performing phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a baseband signal after phase rotation.

[0065] Before performing multi-phase decomposition on the baseband data, the Doppler frequency search interval is used to perform phase rotation on the resampled baseband data to convert the baseband data into a baseband signal, which is used to calculate the correlation value of the multi-phase component of the search grid.

[0066] Step 106, using the phase-rotated baseband signal, calculate all search squares within a preset code phase search square range to obtain multiphase component correlation values ​​of all search squares.

[0067] According to the fact that the sampling rate of the resampled baseband data is just a multiple of the code rate P, the code phase interval is set to 1 / P, and then the multi-phase component correlation values ​​of the P phases of all search squares within the preset code phase search square range are calculated using the phase-rotated baseband signal and the spread spectrum code to complete the code phase time domain search.

[0068] Step 108, performing correlation value calculation within a preset Doppler search grid range according to the multiphase component correlation values ​​of all search grids, to obtain correlation values ​​corresponding to all search grids.

[0069] The correlation values ​​corresponding to all search squares within the Doppler search square are calculated using the multi-phase component correlation values ​​of P phases of all search squares.

[0070] Step 110, performing capture decision on the BOC signal to be captured according to the correlation values ​​corresponding to all search grids.

[0071] According to the capture results, the present application reduces the computational complexity to n / 2(m+n) times of the traditional capture method by setting the optimal code phase search interval 1 / P, thereby greatly improving the BOC signal capture and detection efficiency.

[0072] In the above-mentioned high-efficiency BOC signal capture method, the above-mentioned high-efficiency BOC signal capture method, device, computer equipment and storage medium first resample the baseband data of the BOC signal so that the sampling rate of the resampled baseband data is equal to the multiple of the code rate. Since the sampling rate of the resampled baseband data is just the multiple of the code rate, the baseband data can be subjected to multi-phase decomposition of multiple extraction, and the correlation value is decomposed into multi-phase component correlation values ​​of the same phase as the multiple. When the code phase search interval is 1 / multiple code chip, the multi-phase component correlation values ​​corresponding to different search code phases can be efficiently reused, thereby reducing the complexity of correlation value calculation, thereby improving the BOC signal capture detection efficiency.

[0073] In one of the embodiments, the sampling rate of the resampled baseband data is a multiple of the bit rate of the BOC signal.

[0074] In one embodiment, performing phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a phase-rotated baseband signal includes:

[0075] The resampled baseband data is phase rotated according to the Doppler frequency search interval, and the baseband signal after phase rotation is obtained as:

[0076] s′ v [k] = s′[k] exp{-j2πvf Δ kT′ s}

[0077] Among them, s′ v [k] represents the baseband signal after phase rotation, s′[k] represents the resampled baseband data, and f Δ is the Doppler frequency search interval, v represents the sequence number of the Doppler search grid, T′ s It represents the sampling period of the resampled baseband data, j is the imaginary unit, and k represents the data sequence number.

[0078] In one embodiment, all search squares within a preset code phase search square range are calculated using the phase-rotated baseband signal to obtain multiphase component correlation values ​​of all search squares, including:

[0079] The code phase search grid range is predefined as 0≤u≤U; wherein u represents the sequence number of the code phase search grid, and U represents the number of the code phase search grid;

[0080] The phase-rotated baseband signal is used to calculate all search squares within the preset code phase search square range, and the multiphase component correlation values ​​of all search squares are obtained as follows:

[0081]

[0082] Where P represents the number of phases in the search grid, p represents the phase sequence number of the search grid, and c n [k] represents the spreading code c n The kth chip of c / T′ s represents the coherent integration time T c The corresponding number of data points.

[0083] like Figure 2 As shown, for the BOC (1, 1) signal, the present application first converts the baseband data rate into 4×1.023MHz by resampling, then performs phase rotation according to the Doppler frequency search interval, performs multi-phase decomposition on the phase-rotated data by 4-fold extraction, and finally directly correlates and accumulates each data with the spread spectrum code to obtain 4-way multi-phase component correlation values ​​of different search code phases.

[0084] In one embodiment, the number of phases in the search grid is the same as a multiple of the code rate.

[0085] Since the sampling rate of the baseband data after resampling is exactly P times the code rate, the baseband data can be subjected to P times multi-phase decomposition, and the correlation value can be decomposed into multi-phase component correlation values ​​of P phases. When the code phase search interval is 1 / P code chips, the multi-phase component correlation values ​​corresponding to different search code phases can be efficiently reused, thereby reducing the complexity of correlation value calculation.

[0086] In one embodiment, correlation values ​​are calculated within a preset Doppler search grid range according to the multiphase component correlation values ​​of all search grids to obtain correlation values ​​corresponding to all search grids, including:

[0087] The preset Doppler search grid range is -V≤v≤V;

[0088] The correlation values ​​of the multiphase components of all search grids are calculated within the preset Doppler search grid range according to the correlation values ​​of the multiphase components of all search grids. The correlation values ​​corresponding to all search grids are obtained as follows:

[0089]

[0090] Wherein, i represents the serial number of the correlation value, and V represents the range of the Doppler search grid.

[0091] like Figure 3 As shown, the multiphase component correlation value w u，v Based on [p], the correlation value z of each search grid can be obtained by summing u，v [i] The present application can also be applied to parallel search algorithms in the time domain or frequency domain to further improve the computational efficiency of the signal capture search link.

[0092] In one embodiment, g[pi] represents the sign of the combination of multi-phase component related values, and the specific values ​​are as follows:

[0093]

[0094] In one embodiment, performing a capture decision on a BOC signal to be captured according to the correlation values ​​corresponding to all search grids includes:

[0095] The detection statistic is calculated based on the correlation values ​​of all search squares, and is compared with the preset capture threshold. If the detection statistic is greater than or equal to the capture threshold, it means that the BOC signal is captured. If the detection statistic is greater than or equal to the capture threshold, it means that the BOC signal is not captured.

[0096] In one embodiment, the detection statistic is calculated based on the correlation values ​​of all search squares, including:

[0097] The detection statistic is calculated based on the correlation values ​​of all search squares: Wherein, L represents the number of post-accumulations.

[0098] 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.

[0099] In one embodiment, Figure 4 As shown, a highly efficient BOC signal capture device is provided, comprising: a resampling module 402, a phase rotation module 404, a multi-phase component correlation value calculation module 406, a correlation value calculation module 408 and a capture decision module 410, wherein:

[0100] The resampling module 402 is used to obtain the BOC signal to be captured and resample the baseband data of the BOC signal to obtain resampled baseband data;

[0101] A phase rotation module 404 is used to perform phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a baseband signal after phase rotation;

[0102] A multiphase component correlation value calculation module 406 is used to calculate all search squares within a preset code phase search square range using the phase-rotated baseband signal to obtain multiphase component correlation values ​​of all search squares;

[0103] A correlation value calculation module 408 is used to calculate the correlation value within a preset Doppler search grid range according to the multiphase component correlation values ​​of all search grids to obtain the correlation values ​​corresponding to all search grids;

[0104] The capture decision module 410 is used to make a capture decision on the BOC signal to be captured according to the correlation values ​​corresponding to all the search grids.

[0105] In one of the embodiments, the sampling rate of the resampled baseband data is a multiple of the bit rate of the BOC signal.

[0106] In one embodiment, the phase rotation module 404 is further configured to perform phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a baseband signal after phase rotation, including:

[0107] The resampled baseband data is phase rotated according to the Doppler frequency search interval, and the baseband signal after phase rotation is obtained as:

[0108] s′ v [k] = s′[k] exp{-j2πvf Δ kT′ s}

[0109] Among them, s′ v [k] represents the baseband signal after phase rotation, s′[k] represents the resampled baseband data, and f Δ is the Doppler frequency search interval, v represents the sequence number of the Doppler search grid, T′ s It represents the sampling period of the resampled baseband data, j is the imaginary unit, and k represents the data sequence number.

[0110] In one embodiment, the multiphase component correlation value calculation module 406 is further configured to calculate all search squares within a preset code phase search square range using the phase-rotated baseband signal to obtain multiphase component correlation values ​​of all search squares, including:

[0111] The code phase search grid range is predefined as 0≤u≤U; wherein u represents the sequence number of the code phase search grid, and U represents the number of the code phase search grid;

[0112] The phase-rotated baseband signal is used to calculate all search squares within the preset code phase search square range, and the multiphase component correlation values ​​of all search squares are obtained as follows:

[0113]

[0114] Where P represents the number of phases in the search grid, p represents the phase sequence number of the search grid, and c n [k] represents the spreading code c n The kth chip of c / T′ s represents the coherent integration time T c The corresponding number of data points.

[0115] In one embodiment, the number of phases in the search grid is the same as a multiple of the code rate.

[0116] In one of the embodiments, the correlation value calculation module 408 is further used to, in one of the embodiments, perform correlation value calculations within a preset Doppler search grid range according to the multiphase component correlation values ​​of all search grids to obtain correlation values ​​corresponding to all search grids, including:

[0117] The preset Doppler search grid range is -V≤v≤V;

[0118] The correlation values ​​of the multiphase components of all search grids are calculated within the preset Doppler search grid range according to the correlation values ​​of the multiphase components of all search grids. The correlation values ​​corresponding to all search grids are obtained as follows:

[0119]

[0120] Wherein, i represents the serial number of the correlation value, and V represents the range of the Doppler search grid.

[0121] In one embodiment, g[pi] represents the sign of the combination of multi-phase component related values, and the specific values ​​are as follows:

[0122]

[0123] In one embodiment, the acquisition decision module 410 is further configured to make an acquisition decision on the BOC signal to be captured according to the correlation values ​​corresponding to all search grids, including:

[0124] The detection statistic is calculated based on the correlation values ​​of all search squares, and is compared with the preset capture threshold. If the detection statistic is greater than or equal to the capture threshold, it means that the BOC signal is captured. If the detection statistic is greater than or equal to the capture threshold, it means that the BOC signal is not captured.

[0125] In one embodiment, the detection statistic is calculated based on the correlation values ​​of all search squares, including:

[0126] The detection statistic is calculated based on the correlation values ​​of all search squares: Wherein, L represents the number of post-accumulations.

[0127] For the specific definition of a highly efficient BOC signal capture device, please refer to the definition of a highly efficient BOC signal capture method above, which will not be repeated here. Each module in the above-mentioned highly efficient BOC signal capture device 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.

[0128] 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 5 As 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 highly efficient BOC signal capture method 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 covering the display screen, or a key, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0129] Those skilled in the art will understand that Figure 5 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application 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.

[0130] 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.

[0131] In one embodiment, a computer 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.

[0132] 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 in this application 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).

[0133] 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.

[0134] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A highly efficient BOC signal capture method, characterized in that: The method comprises: Obtain the BOC signal to be captured; Resampling the baseband data of the BOC signal to obtain resampled baseband data; Performing phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a baseband signal after phase rotation; Utilizing the phase-rotated baseband signal to calculate all search squares within a preset code phase search square range, to obtain multiphase component correlation values ​​of all search squares; Calculating correlation values ​​within a preset Doppler search grid range according to the multiphase component correlation values ​​of all search grids to obtain correlation values ​​corresponding to all search grids; A capture decision is made on the BOC signal to be captured according to the correlation values ​​corresponding to all the search grids.

2. The method according to claim 1, characterized in that The sampling rate of the resampled baseband data is a multiple of the bit rate of the BOC signal.

3. The method according to claim 2, characterized in that Performing phase rotation on the resampled baseband data according to the Doppler frequency search interval to obtain a baseband signal after phase rotation, including: The resampled baseband data is phase rotated according to the Doppler frequency search interval, and the baseband signal after phase rotation is obtained as follows: s′ v [k]=s′[k]exp{-j2πvf Δ kT′ s } Among them, s′ v [k] represents the baseband signal after phase rotation, s′[k] represents the resampled baseband data, fΔ is the Doppler frequency search interval, v represents the sequence number of the Doppler search grid, T′ s Represents the sampling period of the resampled baseband data, j is an imaginary unit, and k represents the data sequence number.

4. The method according to claim 3, characterized in that All search squares within a preset code phase search square range are calculated using the phase-rotated baseband signal to obtain multiphase component correlation values ​​of all search squares, including: The code phase search grid range is predefined as 0≤u≤U; wherein u represents the sequence number of the code phase search grid, and U represents the number of the code phase search grid; The phase-rotated baseband signal is used to calculate all search squares within the preset code phase search square range, and the multiphase component correlation values ​​of all search squares are obtained. Where P represents the number of phases in the search grid, p represents the phase sequence number of the search grid, and c n [k] represents the spreading code c n The kth chip of c / T′ s represents the coherent integration time T c The corresponding number of data points.

5. The method according to claim 4, characterized in that The number of phases of the search grid is the same as a multiple of the code rate.

6. The method according to claim 4, characterized in that Correlation values ​​are calculated in a preset Doppler search grid range according to the multiphase component correlation values ​​of all the search grids to obtain correlation values ​​corresponding to all the search grids, including: The preset Doppler search grid range is -V≤v≤V; The correlation values ​​corresponding to all the search grids are calculated based on the multiphase component correlation values ​​of all the search grids within the preset Doppler search grid range. Wherein, i represents the serial number of the correlation value, and V represents the range of the Doppler search grid.

7. The method according to claim 6, characterized in that The g[pi] represents the sign of the combination of multi-phase component correlation values, and the specific values ​​are as follows: 。 8. The method according to claim 7, characterized in that Performing a capture decision on the BOC signal to be captured according to the correlation values ​​corresponding to all the search grids, including: A detection statistic is calculated based on the correlation values ​​of all the search squares, and the detection statistic is compared with a preset capture threshold. If the detection statistic is greater than or equal to the capture threshold, it indicates that the BOC signal is captured; if the detection statistic is greater than or equal to the capture threshold, it indicates that the BOC signal is not captured.

9. The method according to claim 8, characterized in that Calculate the detection statistic based on the correlation values ​​of all the search squares, including: The detection statistic is calculated based on the correlation values ​​of all search squares: Wherein, L represents the number of post-accumulations.

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