Satellite signal tracking method, navigation receiver and readable storage medium

Abstract

The embodiments of the present application provide a satellite signal tracking method, a navigation receiver and a readable storage medium, and relate to the field of satellite communication technology. The method includes: demodulating the captured satellite signal to obtain a navigation message; determining the bit boundary of the navigation message, and aligning the bit boundary of the navigation message to the local code generated by the navigation receiver to obtain the target information code segment of the navigation message on the local code; controlling the target information code segment to perform a bit flip consistent with the navigation message; obtaining the first correlation peak of the satellite signal according to the local code after the bit flip; adjusting the coherent integration time of the satellite signal according to the first correlation peak, and tracking the satellite signal according to the adjusted coherent integration time. The present application can eliminate the influence of bit flipping, and significantly improve the satellite signal tracking sensitivity by increasing the coherent integration time and enhancing the processing gain of the coherent integration time.

Description

Technical Field

[0001] The present invention relates to the field of satellite communication technology, and in particular to a satellite signal tracking method, a navigation receiver and a readable storage medium. Background Art

[0002] In general navigation systems, the Doppler and code phase of the local code are often adjusted through correlation peaks to achieve continuous and stable tracking of satellite signals. However, when the satellite signal reaches the ground receiver, the signal amplitude is very weak and the correlation peak is not obvious, resulting in large jitter in the Doppler and code phase adjustments, affecting the stability and sensitivity of satellite signal tracking.

[0003] Existing studies have found that extending the coherent integration time helps improve the tracking performance of satellite signals. Among them, the more common method is to extend the coherent integration time by eliminating the impact of inter-bit symbol flipping, but this will increase the amplitude of the satellite signal's background noise accordingly, introduce interference items for the judgment of the correlation peak and increase the amount of calculation. The influence of the navigation message of the satellite signal on the coherent integration can also be eliminated by self-prediction of the navigation message, but the bit error rate of the predicted navigation message is high, and the satellite signal amplitude will be weakened when the navigation message is stripped. None of the above methods can eliminate the impact of inter-bit symbol flipping while extending the coherent integration time, and cannot improve the stability and sensitivity of satellite signal tracking. Therefore, a high-sensitivity tracking method for satellite signals is urgently needed. Summary of the invention

[0004] In view of this, one of the objectives of the present application is to provide a satellite signal tracking method, a navigation receiver and a readable storage medium to at least solve some of the above-mentioned technical problems.

[0005] In a first aspect, an embodiment of the present application provides a method for tracking a satellite signal, the method comprising:

[0006] Demodulate the captured satellite signal to obtain the navigation message;

[0007] Determining a bit boundary of the navigation message, and aligning the bit boundary of the navigation message to a local code generated by the navigation receiver, so as to obtain a target information code segment of the navigation message on the local code;

[0008] Controlling the target information code segment to perform bit flipping consistent with the navigation message;

[0009] Obtaining a first correlation peak of the satellite signal according to the bit-flipped local code;

[0010] The coherent integration time of the satellite signal is adjusted according to the first correlation peak, and the satellite signal is tracked according to the adjusted coherent integration time.

[0011] Optionally, after the step of “demodulating the captured satellite signal to obtain a navigation message”, the method further includes:

[0012] storing the navigation message and determining whether the navigation message is in a storage complete state and a verification accurate state;

[0013] If it is determined that the navigation message is in a storage complete state and a verification accurate state, the step of jumping to execute is to align the bit boundary of the navigation message to the local code generated by the navigation receiver.

[0014] Optionally, after the step of “determining the bit boundary of the navigation message and aligning the bit boundary of the navigation message to the local code generated by the navigation receiver”, the method further includes:

[0015] Acquire an identification frame and time information of the navigation message, and determine a frame boundary of the navigation message and a position of the frame boundary of the navigation message according to the identification frame;

[0016] The frame boundary and time of the local code are adjusted according to the position of the frame boundary of the navigation message and the time information.

[0017] Optionally, after the step of “controlling the target information code segment to perform a bit flip consistent with the navigation message”, the method further includes:

[0018] Acquire a first bit flip state of the target information code segment, a second bit flip state of the navigation message, and a signal-to-noise ratio of the satellite signal;

[0019] Comparing the first bit flip state and the second bit flip state to obtain a first comparison result;

[0020] Comparing the signal-to-noise ratio of the satellite signal with a preset signal-to-noise ratio threshold to obtain a second comparison result;

[0021] The upper limit of the integration time of the satellite signal is adjusted according to the first comparison result and the second comparison result.

[0022] Optionally, the step of “adjusting the coherent integration time of the satellite signal according to the first correlation peak” includes:

[0023] Acquire the amplitude value of the first correlation peak;

[0024] If the amplitude value of the first correlation peak is greater than or equal to a first preset amplitude threshold, reducing the coherent integration time of the satellite signal;

[0025] If the amplitude value of the first correlation peak is less than the first preset amplitude threshold and less than the second preset amplitude threshold, increasing the coherent integration time of the satellite signal according to a preset adjustment number of times, wherein the first preset amplitude threshold is greater than the second preset amplitude threshold;

[0026] If the integration time obtained by increasing the coherent integration time of the satellite signal by the preset adjustment times is greater than the preset integration time upper limit, the coherent integration time of the satellite signal is adjusted to the preset integration time upper limit.

[0027] Optionally, after the step of “determining the bit boundary of the navigation message, and aligning the bit boundary of the navigation message to the local code generated by the navigation receiver to obtain the target information code segment of the navigation message on the local code”, the method further includes:

[0028] If the navigation system used by the satellite transmitting the satellite signal has secondary coding, aligning the bit boundary of the navigation message and the bit boundary of the correlation code with the secondary coding to the local code to obtain a second target information code segment of the navigation message and the correlation code on the local code;

[0029] The second target information code segment is controlled to perform a bit flip that is consistent with the navigation message and the related code.

[0030] Optionally, the step of “obtaining a first correlation peak of the satellite signal according to the bit-flipped local code” includes:

[0031] Performing correlation calculation on the navigation message and the bit-flipped local code to obtain the first correlation peak;

[0032] The step of “tracking the satellite signal according to the adjusted coherent integration time” includes:

[0033] Recalculating the correlation between the navigation message and the bit-flipped local code according to the adjusted integration time, and adjusting the carrier Doppler frequency and code phase of the local code according to a second correlation peak obtained through the correlation calculation;

[0034] The satellite signal is tracked according to the adjusted carrier Doppler frequency and code phase.

[0035] Optionally, the step of “adjusting the carrier Doppler frequency and code phase of the local code according to the second correlation peak obtained through correlation calculation” includes:

[0036] Adjusting the carrier Doppler frequency according to a first preset adjustment rule, wherein the first preset adjustment rule includes at least one of a frequency-locked loop, a phase-locked loop, and a frequency-locked phase-locked loop;

[0037] The code phase is adjusted according to a second preset adjustment rule, wherein the second preset adjustment rule includes a delay locked loop.

[0038] In a second aspect, an embodiment of the present application provides a navigation receiver, comprising a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the satellite signal tracking method provided in the first aspect is implemented.

[0039] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by one or more processors, it implements the satellite signal tracking method provided in the first aspect.

[0040] The satellite signal tracking method provided in the embodiment of the present application can first determine the bit boundary of the navigation message, and then align the bit boundary of the navigation message to the local code generated by the navigation receiver to obtain the target information code segment of the navigation message on the local code, and realize the bit flipping or bit jumping consistent with the target information code segment and the navigation message, thereby realizing the coding modulation of the navigation message and the local code, eliminating the influence of the bit flipping, and can significantly improve the tracking sensitivity of tracking the satellite signal by increasing the coherent integration time and enhancing the processing gain of the coherent integration time. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0042] Figure 1 A schematic diagram of the structure of a navigation receiver provided in an embodiment of the present application is shown;

[0043] Figure 2 A method flow chart of a satellite signal tracking method provided by an embodiment of the present application is shown;

[0044] Figure 3 A schematic diagram of adjusting the coherent integration time involved in a satellite signal tracking method provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0046] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0048] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear to indicate an orientation or position relationship, they are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the product of the invention is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0049] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0050] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0051] See also Figure 1The provided navigation receiver 110 may be an electronic device with signal capture and signal tracking capabilities, and the navigation receiver 110 mainly includes a memory 120 and a processor 130. Among them, the navigation receiver 110 can be used as the action execution subject of the following satellite signal tracking method embodiment. The memory 120 and the processor 130 are electrically connected to each other directly or indirectly to achieve data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines. The navigation receiver 110 includes at least one software function module that can be stored in the memory 120 in the form of software or firmware or solidified in the operating system (OS) of the navigation receiver 110. The processor 130 is used to execute the executable modules stored in the memory 120, such as the software function modules and computer programs included in the navigation receiver 110.

[0052] The memory 120 may be, but is not limited to, a random access memory (RAM), a read only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable read-only memory (EEPROM), etc. The memory 120 is used to store a program, and the processor 130 executes the program after receiving an execution instruction.

[0053] The processor 130 may be an integrated circuit chip with signal processing capabilities. The above-mentioned processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application may be implemented or executed. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0054] See also Figure 2 , Figure 2 A method flow chart of a satellite signal tracking method provided in an embodiment of the present application, and the steps of the satellite signal tracking method will be described in detail below.

[0055] S210, demodulate the captured satellite signal to obtain a navigation message.

[0056] In this embodiment, the capture and demodulation of satellite signals can be realized by the navigation receiver 110 in the above embodiment. Usually, before transmitting satellite signals, the satellite will first perform spread spectrum processing on the navigation message and pseudo-random code, and then send them out after correlation modulation processing, wherein the correlation modulation processing process can adopt the binary phase shift keying (BPSK) method, which can realize the conversion of the analog signal after the spread spectrum processing into a data value.

[0057] Correspondingly, after the navigation receiver captures the satellite signal, it needs to perform despreading processing on the captured satellite signal, and then perform demodulation processing after despreading processing to obtain the navigation message. Among them, the satellite signal transmitted by the satellite mainly refers to the carrier signal, and the navigation message mainly includes the status information of the satellite navigation system, such as system time, clock correction value, orbit data of the satellite corresponding to the signal transmission, approximate orbit information of other satellites, ionosphere model parameters and world coordinated time and other data. The navigation message can be used to calculate the current position information of the satellite and the time of satellite signal transmission, and is a binary code with a certain format, which is sent to the user in frames.

[0058] S220, determining the bit boundary of the navigation message, and aligning the bit boundary of the navigation message to the local code generated by the navigation receiver to obtain the target information code segment of the navigation message on the local code.

[0059] In this embodiment, the navigation message is composed of multiple frames, and each frame message is composed of multiple bits of data. Taking the GPS navigation system as an example, a complete navigation message in one cycle includes 25 pages, which takes 12.5 minutes to complete the transmission, wherein a complete page contains 5 sub-pages, which takes 30 seconds to complete the transmission, a sub-page contains 10 words, which takes 6 seconds to complete the transmission, and a word contains 30 bits, which takes 0.6 seconds to complete the transmission. After the navigation message is obtained, the bit boundary of the navigation message can be determined according to all the bits of the navigation message. Among them, the local code can be generated by the navigation receiver 110 in the above embodiment, which is a code generated in the navigation receiver 110 and includes multiple code phases and multiple code chip lengths. According to the bit boundary of the navigation message, the target information code segment corresponding to the navigation message can be directly confirmed on the local code.

[0060] In a possible implementation manner, after the step of “determining the bit boundary of the navigation message and aligning the bit boundary of the navigation message to the local code generated by the navigation receiver”, the method further includes:

[0061] Acquire an identification frame and time information of the navigation message, and determine a frame boundary of the navigation message and a position of the frame boundary of the navigation message according to the identification frame;

[0062] The frame boundary and time of the local code are adjusted according to the position of the frame boundary of the navigation message and the time information.

[0063] In this embodiment, the frame boundary of the local code can be first determined by the frame boundary of the navigation message, specifically, the frame boundary of the target information code segment in the above embodiment can be determined, and then the time information of the local code is adjusted by the time information corresponding to the navigation message, that is, the time information of the target information code segment on the local code is adjusted to achieve time synchronization between the navigation message and the target information code segment.

[0064] Taking the GPS L1 band system as an example, if the array H represents the navigation message, the array length is 37500 bits, H(1) refers to the message corresponding to 1 frame, 1 word, 1 bit, and the system internal time counts the current time T as superframe M frame N word Z bit Q, find the spliced ​​message H(A) output by the message analysis T ) corresponds to position A T =mod((25(M-1)+5(N-1)+10(Z-1)+Q), 37500), where mod(.) represents remainder calculation. After aligning a certain moment, the subsequent telegrams H(A) are read sequentially.T+i )(i=1,2,...) bit flip, the message position A at time T+1 T+1 =mod((25(M-1)+5(N-1)+10(Z-1)+Q+1), 37500).

[0065] The superframe in this embodiment can be understood as the page or frame in the above embodiment, and the frame in this embodiment can be understood as the subpage in the above embodiment.

[0066] Optionally, after the step of “determining the bit boundary of the navigation message, and aligning the bit boundary of the navigation message to the local code generated by the navigation receiver to obtain the target information code segment of the navigation message on the local code”, the method further includes:

[0067] If the navigation system used by the satellite transmitting the satellite signal has secondary coding, aligning the bit boundary of the navigation message and the bit boundary of the correlation code with the secondary coding to the local code to obtain a second target information code segment of the navigation message and the correlation code on the local code;

[0068] The second target information code segment is controlled to perform a bit flip that is consistent with the navigation message and the related code.

[0069] Considering that different navigation systems process satellite signals differently, such as the Beidou navigation system has secondary coding, which can improve the correlation of the original sequence, in the Beidou navigation system, in order to improve the working performance of Beidou, the ranging code length is usually set to 2 times the C / A code, but this method will increase the capture time, reduce the efficiency of the receiver, and also reduce the sensitivity of the Beidou navigation system. In this embodiment, the navigation message and the code related to the secondary coding, such as the NH code of Beidou, can be directly modulated on the local code, which can also ensure that the navigation message and the corresponding target information code segment of the navigation message in the local code achieve consistent bit flipping.

[0070] S230, controlling the target information code segment to perform a bit flip that is consistent with the navigation message.

[0071] In the above embodiment, the target information code segment corresponding to the navigation message has been confirmed on the local code. In this embodiment, it is only necessary to keep the bit flip of the target information code segment consistent with the bit flip of the navigation message, so as to eliminate the influence of the bit flip on the coherent integration. Generally, when the coherent integration time is too long, the bit flip of the navigation message will have a certain degree of influence on the processing gain of the coherent integration, which will reduce the ability to capture and track weak signals. Eliminating the influence of the bit flip on the coherent integration will increase the processing gain of the coherent integration, improve the ability to capture and track weak signals, that is, improve the tracking sensitivity of weak signals. The time of the coherent integration can be adaptively adjusted in the subsequent operation process.

[0072] S240: Obtain a first correlation peak of the satellite signal according to the bit-flipped local code.

[0073] S250: Adjust the coherent integration time of the satellite signal according to the first correlation peak, and track the satellite signal according to the adjusted coherent integration time.

[0074] In this embodiment, after obtaining the bit-flipped local code, the bit-flipped local code is correlated with the captured satellite signal to obtain the first correlation peak of the satellite signal. Specifically, at least one evaluation algorithm selected from the group consisting of delta value detection, unilateral slope detection, and polynomial fitting can be used to calculate the first correlation peak of the satellite signal.

[0075] In a possible implementation manner, the step of “obtaining a first correlation peak of the satellite signal according to the bit-flipped local code” includes:

[0076] Performing correlation calculation on the navigation message and the bit-flipped local code to obtain the first correlation peak;

[0077] The step of “tracking the satellite signal according to the adjusted coherent integration time” includes:

[0078] Recalculating the correlation between the navigation message and the bit-flipped local code according to the adjusted integration time, and adjusting the carrier Doppler frequency and code phase of the local code according to a second correlation peak obtained through the correlation calculation;

[0079] The satellite signal is tracked according to the adjusted carrier Doppler frequency and code phase.

[0080] The above embodiment has eliminated the influence of the bit flip of the navigation potential on the coherent integration gain, and the coherent integration time can be appropriately increased to improve the sensitivity of satellite signal tracking. The calculation method of the second correlation peak obtained after the correlation calculation in this embodiment can refer to the process of calculating the first correlation peak in the above embodiment, and will not be repeated here.

[0081] From the above analysis, it can be seen that the satellite signal tracking method provided in the embodiment of the present application can first determine the bit boundary of the navigation message, and then align the bit boundary of the navigation message to the local code generated by the navigation receiver to obtain the target information code segment of the navigation message on the local code, and realize the bit flipping or bit jumping consistent with the target information code segment and the navigation message, thereby realizing the coding modulation of the navigation message and the local code, eliminating the influence of bit flipping, and can significantly improve the tracking sensitivity of tracking the satellite signal by increasing the coherent integration time and enhancing the processing gain of the coherent integration time.

[0082] In a possible implementation manner, the step of “adjusting the carrier Doppler frequency and code phase of the local code according to the second correlation peak obtained through correlation calculation” includes:

[0083] Adjusting the carrier Doppler frequency according to a first preset adjustment rule, wherein the first preset adjustment rule includes at least one of a frequency-locked loop, a phase-locked loop, and a frequency-locked phase-locked loop;

[0084] The code phase is adjusted according to a second preset adjustment rule, wherein the second preset adjustment rule includes a delay locked loop.

[0085] This embodiment does not limit the method that can be used to calculate the carrier Doppler frequency and the code phase, and the calculation method can be selected according to actual needs.

[0086] Optionally, after the step of “demodulating the captured satellite signal to obtain a navigation message”, the method further includes:

[0087] storing the navigation message and determining whether the navigation message is in a storage complete state and a verification accurate state;

[0088] If it is determined that the navigation message is in a storage complete state and a verification accurate state, the step of jumping to execute is to align the bit boundary of the navigation message to the local code generated by the navigation receiver.

[0089] In this embodiment, the integrity and accuracy of the stored navigation message need to be checked. Only when the stored navigation message is complete and accurate can the step of aligning the bit boundaries be further performed.

[0090] Specifically, the storage length and cyclic redundancy check code of the stored navigation message can be obtained. If the storage length is equal to the preset length, the stored navigation message is determined to be complete. Then, a cyclic redundancy check operation is performed on the cyclic redundancy check code to obtain a check result. If the check result indicates that it is correct, the stored navigation message is determined to be accurate.

[0091] A flag bit may also be configured for the navigation message that has passed the verification, such as configuring a first flag bit for the navigation message that has passed the integrity verification, and configuring a second flag bit for the navigation message that has passed the accuracy verification, wherein the flag bit being in a set state indicates that the navigation message is complete or accurate. This embodiment significantly reduces the bit error rate for message analysis such as navigation messages that have passed the verification.

[0092] Optionally, after the step of “controlling the target information code segment to perform a bit flip consistent with the navigation message”, the method further includes:

[0093] Acquire a first bit flip state of the target information code segment, a second bit flip state of the navigation message, and a signal-to-noise ratio of the satellite signal;

[0094] Comparing the first bit flip state and the second bit flip state to obtain a first comparison result;

[0095] Comparing the signal-to-noise ratio of the satellite signal with a preset signal-to-noise ratio threshold to obtain a second comparison result;

[0096] The upper limit of the integration time of the satellite signal is adjusted according to the first comparison result and the second comparison result.

[0097] Specifically, adjusting the upper limit of the integration time of the satellite signal according to the first comparison result and the second comparison result includes:

[0098] If the signal-to-noise ratio is less than or equal to a preset signal-to-noise ratio threshold and the first bit flip state is the same as the second bit flip state, adjusting the upper limit of the integration time of the satellite signal to a first preset integration time threshold;

[0099] If the signal-to-noise ratio is greater than the preset signal-to-noise ratio threshold and / or the first bit flip state and the second bit flip state are different, the upper limit of the integration time of the satellite signal is adjusted to a second preset integration time threshold, wherein the first preset integration time is preset to be greater than the second preset integration time threshold.

[0100] The preset time threshold in this embodiment can be selected according to actual usage.

[0101] Optionally, the step of “adjusting the coherent integration time of the satellite signal according to the first correlation peak” includes:

[0102] Acquire the amplitude value of the first correlation peak;

[0103] If the amplitude value of the first correlation peak is greater than or equal to a first preset amplitude threshold, reducing the coherent integration time of the satellite signal;

[0104] If the amplitude value of the first correlation peak is less than the first preset amplitude threshold and less than the second preset amplitude threshold, increasing the coherent integration time of the satellite signal according to a preset adjustment number of times, wherein the first preset amplitude threshold is greater than the second preset amplitude threshold;

[0105] If the integration time obtained by increasing the coherent integration time of the satellite signal by the preset adjustment times is greater than the preset integration time upper limit, the coherent integration time of the satellite signal is adjusted to the preset integration time upper limit.

[0106] For a detailed explanation of the process of adjusting the coherent integration time, see Figure 3 , Figure 3 A schematic diagram of adjusting the coherent integration time involved in a satellite signal tracking method provided in an embodiment of the present application. Wherein, S1 represents a first bit flip state, S2 represents a second bit flip state, SNR represents a signal-to-noise ratio, L represents a preset signal-to-noise ratio threshold, T1 represents a first preset integration time threshold, T2 represents a second preset integration time threshold, F represents an amplitude value of a first correlation peak, F1 represents a first preset amplitude threshold, F2 represents a second preset amplitude threshold, and t represents a coherent integration time.

[0107] In summary, the satellite signal tracking method provided in the embodiment of the present application can first determine the bit boundary of the navigation message, and then align the bit boundary of the navigation message to the local code generated by the navigation receiver to obtain the target information code segment of the navigation message on the local code, and realize the bit flipping or bit jumping consistent with the target information code segment and the navigation message, thereby realizing the coding modulation of the navigation message and the local code, eliminating the influence of bit flipping, and can significantly improve the tracking sensitivity of tracking the satellite signal by increasing the coherent integration time and enhancing the processing gain of the coherent integration time.

[0108] The embodiment of the present application also discloses a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the satellite signal tracking method described in the method embodiment is implemented. Similarly, by increasing the coherent integration time and enhancing the processing gain of the coherent integration time, the tracking sensitivity of tracking satellite signals can be significantly improved.

[0109] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for tracking satellite signals, characterized in that: Applied to a navigation receiver, the satellite signal tracking method includes: Demodulate the captured satellite signal to obtain the navigation message; Determining a bit boundary of the navigation message, and aligning the bit boundary of the navigation message to a local code generated by the navigation receiver, so as to obtain a target information code segment of the navigation message on the local code; Controlling the target information code segment to perform bit flipping consistent with the navigation message; Obtaining a first correlation peak of the satellite signal according to the bit-flipped local code; The coherent integration time of the satellite signal is adjusted according to the first correlation peak, and the satellite signal is tracked according to the adjusted coherent integration time.

2. The satellite signal tracking method according to claim 1, characterized in that: After the step of "demodulating the captured satellite signal to obtain a navigation message", the method further comprises: storing the navigation message and determining whether the navigation message is in a storage complete state and a verification accurate state; If it is determined that the navigation message is in a storage complete state and a verification accurate state, the step of jumping to execute is to align the bit boundary of the navigation message to the local code generated by the navigation receiver.

3. The satellite signal tracking method according to claim 1, characterized in that: After the step of "determining the bit boundary of the navigation message and aligning the bit boundary of the navigation message to the local code generated by the navigation receiver", the method further includes: Acquire an identification frame and time information of the navigation message, and determine a frame boundary of the navigation message and a position of the frame boundary of the navigation message according to the identification frame; The frame boundary and time of the local code are adjusted according to the position of the frame boundary of the navigation message and the time information.

4. The satellite signal tracking method according to claim 1, characterized in that: After the step of "controlling the target information code segment to perform bit flipping consistent with the navigation message", the method further includes: Acquire a first bit flip state of the target information code segment, a second bit flip state of the navigation message, and a signal-to-noise ratio of the satellite signal; Comparing the first bit flip state and the second bit flip state to obtain a first comparison result; Comparing the signal-to-noise ratio of the satellite signal with a preset signal-to-noise ratio threshold to obtain a second comparison result; The upper limit of the integration time of the satellite signal is adjusted according to the first comparison result and the second comparison result.

5. The satellite signal tracking method according to claim 1, characterized in that: The step of “adjusting the coherent integration time of the satellite signal according to the first correlation peak” comprises: Acquire the amplitude value of the first correlation peak; If the amplitude value of the first correlation peak is greater than or equal to a first preset amplitude threshold, reducing the coherent integration time of the satellite signal; If the amplitude value of the first correlation peak is less than the first preset amplitude threshold and less than the second preset amplitude threshold, increasing the coherent integration time of the satellite signal according to a preset adjustment number of times, wherein the first preset amplitude threshold is greater than the second preset amplitude threshold; If the integration time obtained by increasing the coherent integration time of the satellite signal by the preset adjustment times is greater than the preset integration time upper limit, the coherent integration time of the satellite signal is adjusted to the preset integration time upper limit.

6. The satellite signal tracking method according to claim 1, characterized in that: After the step of "determining the bit boundary of the navigation message, and aligning the bit boundary of the navigation message to the local code generated by the navigation receiver to obtain the target information code segment of the navigation message on the local code", the method further includes: If the navigation system used by the satellite transmitting the satellite signal has secondary coding, aligning the bit boundary of the navigation message and the bit boundary of the correlation code with the secondary coding to the local code to obtain a second target information code segment of the navigation message and the correlation code on the local code; The second target information code segment is controlled to perform a bit flip that is consistent with the navigation message and the related code.

7. The satellite signal tracking method according to claim 1, characterized in that: The step of "obtaining a first correlation peak of the satellite signal according to the bit-flipped local code" includes: Performing correlation calculation on the navigation message and the bit-flipped local code to obtain the first correlation peak; The step of "tracking the satellite signal according to the adjusted coherent integration time" includes: Re-calculating the correlation between the navigation message and the bit-flipped local code according to the adjusted integration time, and adjusting the carrier Doppler frequency and code phase of the local code according to a second correlation peak obtained through the correlation calculation; The satellite signal is tracked according to the adjusted carrier Doppler frequency and code phase.

8. The satellite signal tracking method according to claim 7, characterized in that: The step of "adjusting the carrier Doppler frequency and code phase of the local code according to the second correlation peak obtained by correlation calculation" includes: Adjusting the carrier Doppler frequency according to a first preset adjustment rule, wherein the first preset adjustment rule includes at least one of a frequency-locked loop, a phase-locked loop, and a frequency-locked phase-locked loop; The code phase is adjusted according to a second preset adjustment rule, wherein the second preset adjustment rule includes a delay locked loop.

9. A navigation receiver, characterized in that: The navigation receiver includes a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the satellite signal tracking method according to any one of claims 1 to 8 is implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, which, when executed by one or more processors, implements the satellite signal tracking method according to any one of claims 1 to 8.

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