Method, apparatus, device and storage medium for capturing satellite radio determination signals

Abstract

The satellite radio determination signal acquisition method, device, equipment, and storage medium provided by the present invention can preprocess the received satellite radio determination signal, and then obtain the baseband signal in the satellite radio determination signal. Then, based on the current local pseudo-code and the preset coherent integration time, segmented matched filtering processing is performed on the baseband signal. Frequency discrimination and non-coherent integration are sequentially performed on the result of the segmented matched filtering processing to obtain a non-coherent integration result, where the accumulation times of the non-coherent integration are obtained based on the preset coherent integration time and the frame duration of the satellite radio determination signal. Finally, based on the non-coherent integration result, acquisition decision is made on the satellite radio determination signal. By increasing the coherent integration time by crossing odd-numbered message bits and setting the total integration time to the data frame duration for signal acquisition, the present invention greatly improves the acquisition sensitivity of the RDSS signal without increasing the acquisition time.

Description

Technical Field

[0001] The present invention relates to the technical field of signal acquisition, and particularly relates to a method, device, equipment and storage medium for acquiring satellite radiodetermination signals. Background Art

[0002] With the completion of the construction of the Beidou Navigation Satellite System and its official operation in recent years, its service scope has been able to cover the globe. As one of the most distinctive features of the Beidou Satellite Navigation System, RDSS (Radio Determination Satellite Service) has added RDSS inbound and outbound signals. Through the optimization of signal system design and the improvement of satellite payload capabilities, the Beidou-3 RDSS communication service can currently support a maximum of 1000 Chinese characters per single time, while reducing the transmitting power of the terminal and improving the inbound capacity of the system.

[0003] With the optimization of the Beidou-3 RDSS signal system and the improvement of the information transmission rate, higher requirements are also put forward for the receiving performance of user terminals. Most of the existing acquisition algorithms for RDSS signals adopt traditional methods similar to those for RNSS (Radio Navigation Satellite Service) signal acquisition. However, due to the high symbol transmission rate of RDSS signals reaching 32 kbps, the existing acquisition methods are no longer applicable, resulting in very low acquisition sensitivity and detection probability. Summary of the Invention

[0004] In order to solve the problems of low sensitivity and low detection probability in the prior art, the present invention provides a method, device, equipment and storage medium for acquiring satellite radiodetermination signals, which have the characteristics of higher sensitivity, detection probability, etc.

[0005] A method for acquiring a satellite radiodetermination signal according to a specific embodiment of the present invention includes:

[0006] Preprocessing the received satellite radiodetermination signal to obtain the baseband signal in the satellite radiodetermination signal;

[0007] Performing segmented matched filtering processing on the baseband signal based on the current local pseudo-code and a preset coherent integration time, where the preset coherent integration time includes the single telegram transmission time of a preset number of the satellite radiodetermination signals, and the preset number is an odd number not less than 3;

[0008] Performing frequency discrimination and non-coherent integration on the result of the segmented matched filtering processing in sequence to obtain a non-coherent integration result, where the accumulation times of the non-coherent integration are obtained based on the preset coherent integration time and the frame duration of the satellite radiodetermination signal;

[0009] Performing acquisition decision on the satellite radiodetermination signal based on the non-coherent integration result.

[0010] Further, the process of determining the preset coherent integration time includes:

[0011] Cut each type of sub-frame starting from each accumulation starting point with a fixed odd number of messages as the step size;

[0012] Obtain the percentage of the number of cut segments with the same message symbols in adjacent messages in all cut segments;

[0013] Determine the gain of coherent integration at each cut step based on the percentage and the step size;

[0014] Take the transmission time of a single message included in the maximum gain of coherent integration as the preset coherent integration time.

[0015] Further, the number of accumulations of the non-coherent integration is obtained based on the preset coherent integration time and the sub-frame duration of the satellite radio determination signal, including:

[0016] Divide the sub-frame duration of the satellite radio determination signal by the preset coherent integration time to obtain the number of accumulations of the non-coherent integration.

[0017] Further, the capture decision on the satellite radio determination signal based on the non-coherent integration result includes:

[0018] Obtain the peak-to-average ratio based on the non-coherent integration result;

[0019] Determine the capture result based on the peak-to-average ratio and a preset threshold. If the peak-to-average ratio is greater than the preset threshold, the capture is successful; if the peak-to-average ratio is not greater than the preset threshold, the capture fails.

[0020] Further, if the capture fails, the method further includes:

[0021] Re-perform segmented matched filtering processing on the baseband signal based on the updated local pseudo-code and the preset coherent integration time;

[0022] Perform frequency discrimination and non-coherent integration on the result of the re-segmented matched filtering processing in sequence to obtain a new non-coherent integration result;

[0023] Re-perform capture decision on the satellite radio determination signal based on the new non-coherent integration result.

[0024] Further, after preprocessing the received satellite radio determination signal to obtain the baseband signal in the satellite radio determination signal, it further includes:

[0025] After performing anti-aliasing filtering on the baseband signal, perform sampling with a sampling frequency twice the local pseudo-code rate.

[0026] Further, sampling the baseband signal after anti-aliasing filtering includes:

[0027] Accumulating based on a phase accumulation step size, and enabling corresponding sampling points to sample the baseband signal whenever the accumulation result overflows. The phase accumulation step size is:

[0028]

[0029] where f sample is the sampling frequency, and f code is the pseudo-code rate.

[0030] A satellite radio determination signal acquisition device according to a specific embodiment of the present invention includes:

[0031] A preprocessing module for preprocessing the received satellite radio determination signal to obtain the baseband signal in the satellite radio determination signal;

[0032] A coherent integration module for performing segmented matched filtering on the baseband signal based on the current local pseudo-code and a preset coherent integration time. The preset coherent integration time includes the single telegram transmission time of the satellite radio determination signal for a preset number of times, and the preset number is an odd number not less than 3;

[0033] A non-coherent integration module for sequentially performing frequency discrimination and non-coherent integration on the result of the segmented matched filtering to obtain a non-coherent integration result. The accumulation times of the non-coherent integration are obtained based on the preset coherent integration time and the frame duration of the satellite radio determination signal; and

[0034] An acquisition decision module for making an acquisition decision on the satellite radio determination signal based on the non-coherent integration result.

[0035] A device according to a specific embodiment of the present invention includes: a memory and a processor;

[0036] The memory is used for storing a program;

[0037] The processor is used for executing the program to implement each step of the satellite radio determination signal acquisition method as described above.

[0038] A storage medium according to a specific embodiment of the present invention has a computer program stored thereon. When the computer program is executed by a processor, each step of the satellite radio determination signal acquisition method as described above is implemented.

[0039] The satellite radio determination signal acquisition method provided by the present invention can preprocess the received satellite radio determination signal, and then obtain the baseband signal in the satellite radio determination signal. Then, based on the current local pseudo-code and the preset coherent integration time, segmented matched filtering processing is performed on the baseband signal, where the preset coherent integration time includes the single message transmission time of the preset number of satellite radio determination signals, and the preset number is an odd number not less than 3. Frequency discrimination and non-coherent integration are sequentially performed on the result of the segmented matched filtering processing to obtain the non-coherent integration result, where the accumulation times of the non-coherent integration are obtained based on the preset coherent integration time and the frame duration of the satellite radio determination signal. Finally, capture decision is performed on the satellite radio determination signal based on the non-coherent integration result. In the satellite radio determination signal acquisition method, the coherent integration time is increased by crossing an odd number of message bits, and the total integration time is set to the data frame duration for signal acquisition. Without increasing the acquisition time, the acquisition sensitivity of the RDSS signal is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without creative efforts.

[0041] Figure 1 is a flowchart of a satellite radio determination signal acquisition method provided according to an exemplary embodiment;

[0042] Figure 2 is a flowchart for determining the coherent integration time provided according to an exemplary embodiment;

[0043] Figure 3 is a distribution diagram of 3-bit integration values of two service types provided according to an exemplary embodiment;

[0044] Figure 4 is a distribution diagram of 5-bit integration values of two service types provided according to an exemplary embodiment;

[0045] Figure 5 is a capture result diagram provided according to an exemplary embodiment;

[0046] Figure 6 is another flowchart of a satellite radio determination signal acquisition method provided according to an exemplary embodiment;

[0047] Figure 7 is a structural diagram of a satellite radio determination signal acquisition device provided according to an exemplary embodiment;

[0048] Figure 8 It is a structural diagram of a device provided according to an exemplary embodiment. Detailed implementation manners

[0049] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0050] The existing acquisition algorithms for Beidou RDSS signals usually adopt a similar acquisition method for traditional RNSS signals. However, after the upgrade and update, the RDSS service requires a high information transmission rate to ensure system capacity. In the Beidou-3 system, the symbol rate can reach 32 kbit / s. According to the existing signal acquisition method, the maximum coherent integration time can only be 0.03125 ms, that is, the coherent integration is performed for the single telegram transmission time, resulting in a relatively low spreading gain. In order to improve the signal acquisition sensitivity and probability, only non-coherent accumulation can be used for integration. However, due to the square loss existing in non-coherent accumulation, the acquisition sensitivity and detection probability of the existing signal acquisition method are very low. The final acquisition sensitivity can only reach about -130 dBm, which can no longer meet the requirements of signal processing.

[0051] The inventor obtained the telegram distribution characteristics by statistically analyzing the data frame structure of the RDSS signal, and found that the acquisition sensitivity and probability of the Beidou RDSS signal can be effectively improved by adopting the method of increasing the coherent integration time by crossing odd-numbered telegram bits and setting the total integration time (the sum of the coherent integration and non-coherent integration times) to the sub-frame duration of the satellite radio determination signal.

[0052] Specifically, referring to Figure 1 As shown, the present invention provides a method for acquiring a satellite radio determination signal, and the method may include the following steps:

[0053] 101. Preprocess the received satellite radio determination signal to obtain the baseband signal in the satellite radio determination signal.

[0054] The received RDSS downlink digital intermediate frequency signal on the satellite side is first multiplied by the local carrier for mixing processing, so as to convert the satellite radio determination signal to zero intermediate frequency, and directly convert the satellite radio determination radio frequency signal to the baseband signal. When performing local carrier stripping, the Sin / Cos values used can be obtained through the carrier NCO phase lookup table. The NCO phase is 32 Bit, of which the high 6 bits are used for Sin / Cos table lookup, and the depth of the lookup table is 64.

[0055] 102. Perform segmented matched filtering processing on the baseband signal based on the current local pseudo-code and the preset coherent integration time. The preset coherent integration time includes the single message transmission time of the preset number of satellite radio determination signals, and the preset number is an odd number not less than 3.

[0056] Specifically, to reduce the computational complexity of subsequent data processing, a downsampling operation can be performed after obtaining the baseband signal with the intermediate frequency stripped. Before performing downsampling, to prevent spectral aliasing in the baseband signal spectrum, an anti-aliasing filtering can be performed followed by a signal decimation downsampling operation. According to the Nyquist sampling theorem, the sampling rate can be reduced to 2 times the pseudo-code rate. Then multiply the current local pseudo-code by the baseband signal after downsampling, and perform segmented matched filtering processing according to the configured cross-odd-number message bit coherent integration time. The coherent integration adopted by the existing signal acquisition methods cannot cross messages, because if the message flips, the coherent accumulation results of the previous and subsequent epochs will cancel each other out, and no correlation peak can be obtained. According to the downlink data frame structure information of the RDSS signal, by statistically analyzing its message distribution characteristics, the duration of the odd message bits, that is, N*0.03125ms, can be selected as the coherent integration time, where N is an odd number not less than 3.

[0057] For example, the durations of 3 telegrams as coherent integration will produce 2 kinds of accumulation results: The first is that all 3 telegrams have the same sign, and the optimal accumulation result at this time is 3*P. The second is that 2 of the 3 telegrams have the same sign and the other has the opposite sign. The worst accumulation result at this time is 1*P. The reason for selecting an odd number of times is precisely to ensure that at least one telegram bit's integration result is valid in the result of each coherent integration. The higher the proportion of 3-bit telegrams with the same sign within the total integration time, the greater the coherent integration gain. The minimum unit of the data structure of the RDSS downlink signal is a sub-frame, with a time slot of 125 ms. Each time slot contains a public segment and a private segment. The information in the public segment is generally the same for each sub-frame. Different data information is distributed in the private segment according to different service types, such as communication functions, positioning functions, etc. There are 3 kinds of accumulation methods for the coherent integration of the durations of 3 telegram bits according to different accumulation starting points: The first is the state with 0-bit offset, 1bit+2bit+3bit, 4bit+5bit+6bit, and so on. The second is the state with 1-bit offset, 2bit+3bit+4bit, 5bit+6bit+7bit, and so on. The third is the state with 2-bit offset, 3bit+4bit+5bit, 6bit+7bit+8bit, and so on. By statistically analyzing the telegram accumulation distribution in units of data frames for the three accumulation methods of different service types, and counting according to two situations: 3-bit telegrams with the same sign (the highest gain) and 2 bits with the same sign and 1 bit with the opposite sign (the gain is the same as that of a single bit), the ratio of the two is approximately 1:3. The accumulation situations of other odd numbers are similar, where referring to Figure 3 and Figure 4 As shown, the 3-bit accumulation results and 5-bit accumulation results of the satellite radio determination signals of two service types are given respectively. It can be seen from the comparison that the result of 3-bit accumulation is the best. In actual application, the sensitivity of signal acquisition can be increased by about 3 dB to 5 dB. Therefore, the duration of 3 telegram bits, that is, 3*0.03125 ms, can be selected as the coherent integration time.

[0058] 103. The results after segmented matched filtering processing are successively subjected to frequency discrimination and non-coherent integration to obtain non-coherent integration results. The accumulation times of non-coherent integration are obtained based on the preset coherent integration time and the sub-frame duration of the satellite radio determination signal.

[0059] The result of segmented matching filtering is sent to the fast Fourier transform module for frequency discrimination. To balance frequency resolution and computational complexity, the number of points N for fast Fourier transform operations can be set to 256. To further improve the detection probability, non-coherent accumulation is performed on the fast Fourier transform result. The number of non-coherent accumulation times is selected as 1333 times, that is, 125ms / (3*0.03125ms) = 1333. Here, 125ms is the frame duration of RDSS downlink data. The reason for selecting 125ms as the total integration time is that starting from any moment for cumulative integration, a complete data frame cumulative result can be obtained, thus ensuring that high-quality detection results can be obtained when starting capture from any moment. Among them, to reduce the effective data bit width, the amplitude addition method can be used during non-coherent accumulation. The capture result after non-coherent accumulation is referred to Figure 5 as shown.

[0060] 104. Perform capture and decision on the satellite radio determination signal based on the non-coherent integration result.

[0061] Perform capture and decision on the data after non-coherent accumulation, find the peak value of the 256 non-coherent accumulation results, that is, find the maximum value among the 256 data by comparing one by one. Then calculate the peak-to-average ratio based on the average value of the 256 data, and compare the peak-to-average ratio with the preset threshold. If the obtained peak-to-average ratio is greater than the preset threshold, it is determined that the capture is successful; if the peak-to-average ratio is not greater than the preset threshold, it is determined that the capture fails. This capture method for satellite radio determination signals effectively improves the sensitivity and capture probability of RDSS signal capture by adopting the capture method with an odd number of message bit coherent integration times and a signal frame duration of 125ms as the total integration time.

[0062] As a feasible implementation of the above embodiment, referring to Figure 2 as shown, the determination process of the preset coherent integration time may include the following steps:

[0063] 201. Cut each type of frame starting from each accumulation starting point with a fixed odd number of messages as the step size.

[0064] 202. Obtain the percentage of the number of cut segments with the same adjacent message symbols in all cut segments.

[0065] 203. Determine the gain of coherent integration for each cut step size based on the percentage and the step size.

[0066] 204. Use the transmission time of a single message included in the maximum value of the gain of coherent integration as the preset coherent integration time.

[0067] Specifically, according to the framed structure of the RDSS signal, the percentage of consecutive same symbols in different odd-numbered telegrams in the entire data frame can be statistically calculated. The higher the percentage, the greater the gain in capture sensitivity, and the corresponding capture sensitivity is higher. The gain brought is approximately 10log10(N)*ratio, where N is the length of the selected odd-numbered telegram and ratio is the percentage. It needs to be statistically calculated separately according to different service types, so that the statistical results are more accurate. The service types can include positioning functions, communication functions, etc. To facilitate the rapid selection of N, a pure random data can be added for comparison. When specifically applied, it is determined that the gain brought by the coherent integration of 3 telegram bits is the largest.

[0068] When performing downsampling on the obtained baseband signal with the intermediate frequency stripped, the method of cumulative overflow can be adopted, and accumulation is performed based on the phase accumulation step size. Whenever the accumulation result overflows, the corresponding sampling point is enabled to sample the baseband signal. The phase accumulation step size is:

[0069]

[0070] where f sample is the sampling frequency, and f code is the pseudo-code rate.

[0071] In another specific embodiment of the present invention, when the non-coherent accumulation result does not exceed the preset threshold, the capture fails. The capture method for the satellite radio determination signal may further include the following steps:

[0072] 301. Re-segment and match-filter the baseband signal based on the updated local pseudo-code and the preset coherent integration time.

[0073] 302. Perform frequency discrimination and non-coherent integration on the result of the re-segmented and match-filtered processing in sequence to obtain a new non-coherent integration result.

[0074] 303. Re-capture and judge the satellite radio determination signal based on the new non-coherent integration result.

[0075] Specifically, when the non-coherent accumulation result does not exceed the preset threshold, it is determined that a single capture fails, and then the local pseudo-code generator is controlled to slide the code phase, and the above steps 102 to 104 are repeated until all pseudo-code phases are searched.

[0076] As a specific application, referring to Figure 6 as shown, the capture method for the satellite radio determination signal may include the following steps:

[0077] 601. Mix the RDSS downlink acquisition data signal to remove the intermediate frequency carrier frequency.

[0078] 602. Perform anti-aliasing filtering on the zero-IF signal, and then sample to reduce the sampling rate.

[0079] 603. Perform segmented matched filtering for the configured coherent integration time, where appropriate odd-numbered message bits are selected as the coherent integration time according to the message distribution characteristics.

[0080] 604. Perform FFT frequency discrimination on the result of segmented matched filtering.

[0081] 605. Perform a certain number of non-coherent accumulations on the FFT result, where the number of non-coherent accumulations is determined according to the frame duration.

[0082] 606. Perform capture decision based on a preset threshold. When the capture fails, return to step 603 to start over. When the capture is successful, end the capture operation.

[0083] Based on the same design concept, referring to Figure 7 the embodiments of the present invention also provide a capture device for satellite radio determination signals. When the device operates, it can implement each step of the above-mentioned satellite radio determination signal capture method. The device may include:

[0084] A preprocessing module 701 for preprocessing the received satellite radio determination signal to obtain the baseband signal in the satellite radio determination signal.

[0085] A coherent integration module 702 for performing segmented matched filtering on the baseband signal based on the current local pseudo-code and the preset coherent integration time. The preset coherent integration time includes the single message transmission time of the preset number of satellite radio determination signals, and the preset number is an odd number not less than 3.

[0086] A non-coherent integration module 703 for sequentially performing frequency discrimination and non-coherent integration on the result of segmented matched filtering to obtain the non-coherent integration result. The number of accumulations of non-coherent integration is obtained based on the preset coherent integration time and the frame duration of the satellite radio determination signal. And

[0087] A capture decision module 704 for performing capture decision on the satellite radio determination signal based on the non-coherent integration result.

[0088] Further, the coherent integration module 702 is further configured to cut each type of frame starting from each accumulation starting point with a fixed odd number of messages as the step size;

[0089] Obtain the percentage of the number of cut segments with the same adjacent message symbols in all cut segments;

[0090] Determine the gain of coherent integration for each cut step size based on the percentage and the step size;

[0091] The single message transmission time included in the maximum gain of coherent integration is used as the preset coherent integration time.

[0092] Furthermore, the non-coherent integration module 703 is further configured to divide the frame duration of the satellite radio determination signal by the preset coherent integration time to obtain the accumulation times of non-coherent integration.

[0093] Furthermore, the acquisition decision module 704 is specifically configured to obtain the peak-to-average ratio based on the non-coherent integration result;

[0094] Based on the peak-to-average ratio and a preset threshold, an acquisition result is determined. If the peak-to-average ratio is greater than the preset threshold, the acquisition is successful; if the peak-to-average ratio is not greater than the preset threshold, the acquisition fails.

[0095] Furthermore, the coherent integration module 702 is further configured to perform segmented matching filtering processing on the baseband signal again based on the updated local pseudo-code and the preset coherent integration time.

[0096] The non-coherent integration module 703 is further configured to perform frequency discrimination and non-coherent integration on the result of the re-segmented matching filtering processing in sequence to obtain a new non-coherent integration result.

[0097] The acquisition decision module 704 is further configured to perform acquisition decision on the satellite radio determination signal again based on the new non-coherent integration result.

[0098] Furthermore, the acquisition of the satellite radio determination signal further includes a sampling module, configured to perform sampling after anti-aliasing filtering on the baseband signal, and the sampling frequency is twice the local pseudo-code rate.

[0099] Furthermore, the sampling module is specifically configured to perform accumulation based on the phase accumulation step size, and enable the corresponding sampling points to sample the baseband signal whenever the accumulation result overflows. The phase accumulation step size is:

[0100]

[0101] where f sample is the sampling frequency, and f code is the pseudo-code rate

[0102] Referring to Figure 8 as shown, an embodiment of the present invention further provides a device, which may include: a memory 801 and a processor 802.

[0103] The memory 801 is used to store a program.

[0104] The processor 802 is configured to execute the program to implement each step of the method for acquiring a satellite radio determination signal as described in the above embodiment.

[0105] An embodiment of the present invention also provides a storage medium, on which a computer program is stored. When the computer program is executed by a processor, each step of the method for capturing satellite radio determination signals as described in the above embodiments is implemented.

[0106] For the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the present invention is not limited by the described action sequence, because according to the present invention, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0107] It should be noted that each embodiment in this specification is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other. For the device embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiments.

[0108] The steps in the methods of the embodiments of the present invention can be adjusted, combined, and deleted according to actual needs. The technical features recorded in each embodiment can be replaced or combined.

[0109] The modules and sub-modules in the devices and terminals in the embodiments of the present invention can be combined, divided, and deleted according to actual needs.

[0110] In several embodiments provided by the present invention, it should be understood that the disclosed terminals, devices, and methods can be implemented in other ways. For example, the terminal embodiments described above are only illustrative. For example, the division of modules or sub-modules is only a logical function division. In actual implementation, there can be other division methods. For example, multiple sub-modules or modules can be combined or integrated into another module, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection to each other can be through some interfaces. The indirect coupling or communication connection of devices or modules can be in electrical, mechanical, or other forms.

[0111] The modules or sub-modules described as separate components may or may not be physically separated. The components as modules or sub-modules may or may not be physical modules or sub-modules, that is, they can be located in one place, or they can be distributed to multiple network modules or sub-modules. Some or all of the modules or sub-modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0112] In addition, in each embodiment of the present invention, each functional module or sub-module can be integrated into a processing module, or each module or sub-module can exist physically alone, or two or more modules or sub-modules can be integrated into one module. The above-mentioned integrated module or sub-module can be implemented in the form of hardware, or in the form of a software functional module or sub-module.

[0113] Those skilled in the art can further realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0114] The steps of the method or algorithm described in combination with the embodiments disclosed herein can be directly implemented by hardware, a software unit executed by a processor, or a combination of the two. The software unit can be placed in a random access memory (RAM), memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, register, hard disk, removable disk, CD-ROM, or any other form of storage medium well-known in the technical field.

[0115] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for capturing satellite radiodetermination signals, characterized in that, Including: Preprocessing the received satellite radio determination signal to obtain the baseband signal in the satellite radio determination signal; Performing segmented matched filtering processing on the baseband signal based on the current local pseudo-code and a preset coherent integration time, where the preset coherent integration time includes the single message transmission time of a preset number of the satellite radio determination signals, and the preset number is an odd number not less than 3; Successively performing frequency discrimination and non-coherent integration on the result of the segmented matched filtering processing to obtain a non-coherent integration result, where the accumulation times of the non-coherent integration are obtained based on the preset coherent integration time and the frame duration of the satellite radio determination signal; Performing acquisition decision on the satellite radio determination signal based on the non-coherent integration result.

2. The method according to claim 1, wherein The determination process of the preset coherent integration time includes: Cutting each type of frame starting from each accumulation starting point with a fixed odd number of messages as a step; Obtaining the percentage of the number of cut segments with the same adjacent message symbols in all cut segments; Determining the gain of coherent integration at each cut step based on the percentage and the step; Taking the single message transmission time included in the maximum value of the gain of coherent integration as the preset coherent integration time.

3. The method according to claim 1, wherein The accumulation times of the non-coherent integration are obtained based on the preset coherent integration time and the frame duration of the satellite radio determination signal, including: Dividing the frame duration of the satellite radio determination signal by the preset coherent integration time to obtain the accumulation times of the non-coherent integration.

4. The method according to claim 1, wherein The performing acquisition decision on the satellite radio determination signal based on the non-coherent integration result includes: Obtaining the peak-to-average ratio based on the non-coherent integration result; Determining the acquisition result based on the peak-to-average ratio and a preset threshold. If the peak-to-average ratio is greater than the preset threshold, the acquisition is successful; if the peak-to-average ratio is not greater than the preset threshold, the acquisition fails.

5. The method according to claim 4, characterized in that If the acquisition fails, the method further includes: Performing segmented matched filtering processing on the baseband signal again based on the updated local pseudo-code and the preset coherent integration time; Successively performing frequency discrimination and non-coherent integration on the result of the re-segmented matched filtering processing to obtain a new non-coherent integration result; Performing acquisition decision on the satellite radio determination signal again based on the new non-coherent integration result.

6. The method according to claim 1, wherein After preprocessing the received satellite radio determination signal to obtain the baseband signal in the satellite radio determination signal, it further includes: Performing anti-aliasing filtering on the baseband signal and then sampling, where the sampling frequency is twice the local pseudo-code rate.

7. The method according to claim 6, wherein The performing anti-aliasing filtering on the baseband signal and then sampling includes: Accumulating based on the phase accumulation step size, and whenever the accumulation result overflows, making the corresponding sampling point sample the baseband signal, where the phase accumulation step size is: wherein is the sampling frequency, is the pseudo-code rate.

8. A capturing device for satellite radio determination signals, characterized in that, Including: A preprocessing module for preprocessing the received satellite radio determination signal to obtain the baseband signal in the satellite radio determination signal; A coherent integration module for performing segmented matched filtering processing on the baseband signal based on a current local pseudo-code and a preset coherent integration time, where the preset coherent integration time includes the single message transmission time of a preset number of the satellite radio determination signals, and the preset number is an odd number not less than 3; An incoherent integration module for successively performing frequency discrimination and incoherent integration on the result of the segmented matched filtering processing to obtain an incoherent integration result, where the accumulation times of the incoherent integration are obtained based on the preset coherent integration time and the frame duration of the satellite radio determination signal; And A capture decision module for performing capture decision on the satellite radio determination signal based on the incoherent integration result.

9. An electronic device, characterized in that, Comprising: A memory and a processor; The memory for storing a program; The processor for executing the program to implement each step of the method for capturing a satellite radio determination signal as described in any one of claims 1 to 7.

10. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, each step of the method for capturing a satellite radio determination signal as described in any one of claims 1 to 7 is implemented.

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