A positioning method for active interference of navigation signals in complex site environments

Abstract

The invention discloses a positioning method for active interference of navigation signals in a complex site environment, comprising: obtaining satellite telegrams sent by positioning satellites and storing them in telegram data groups, calculating the Poisson distribution probability of the average length of null value runs based on the obtained satellite telegrams, judging whether the navigation signal is interfered with, if there is interference, adjusting the sampling period and generating a positioning optimization signal, constructing an active interference monitoring model based on the positioning optimization signal, determining the interference frequency range and storing it in a data group, adjusting the frequency receiving range of the navigation device based on the interference frequency data group, analyzing the adjusted telegram data group to obtain the available value of the frequency band, comparing it with a threshold value to judge whether the satellite positioning signal is available, marking the unavailable frequency band, and continuing to adjust to the available frequency band. The invention also relates to related computer equipment and storage media, which are conducive to solving the problem of active interference positioning of navigation signals in complex sites.

Description

Technical Field

[0001] The present invention relates to the technical field of active interference positioning, and in particular to a positioning method for active interference of navigation signals in a complex site environment. Background Art

[0002] In complex site environments, navigation signals face many interference sources, which poses a huge challenge to the normal operation of navigation equipment.

[0003] In the prior art, although frequency analysis is performed, the propagation characteristics of the signal in a complex environment and the time-varying characteristics of the interference signal are not fully considered, and the interference frequency range cannot be accurately determined. This makes it difficult for navigation equipment to avoid the interference frequency band in a targeted manner, seriously affecting the accuracy and reliability of navigation. For example, in mountainous areas with severe multipath effects, reflected signals and direct signals are superimposed on each other, and the interference frequency becomes complex and changeable. It is difficult for the prior art to accurately separate the interference frequency from it.

[0004] In the prior art, the determination of frequency band availability is usually simply based on the signal reception situation, without considering the integrity of the message data and the key factors of the null run distribution. This results in misjudging some frequency bands that can receive signals but are actually severely interfered and have unreliable data as available frequency bands, thus affecting the accuracy and stability of navigation.

[0005] To this end, the present invention provides a positioning method for active interference of navigation signals in a complex site environment. Summary of the invention

[0006] The object of the present invention is to provide a method for locating active interference of navigation signals in a complex site environment to solve at least one of the above-mentioned problems of the prior art.

[0007] In a first aspect, the present invention provides a method for locating active interference of navigation signals in a complex site environment, comprising:

[0008] Step 1: Obtain satellite messages sent by positioning satellites and store the satellite messages in a message data group;

[0009] Step 2: Based on the message data group, the probability distribution of the empty character string in the message data group is calculated to obtain the Poisson distribution probability P(k) of the average length of the null value run k, and determine whether there is interference with the navigation signal;

[0010] Step 3: If there is interference in the navigation signal, determine the adjustment time range based on the time length corresponding to the maximum length of the "empty" run in the test data sequence Y and the time length corresponding to the fixed sampling period. Based on the adjustment time range, adjust the fixed sampling period to obtain the Poisson distribution probability P(x) of the average length x of the empty value run after each adjustment. If the Poisson distribution probability P(k) of the average length k of the empty value run after adjustment is higher than the probability threshold, generate a positioning optimization signal.

[0011] Step 4: Based on the positioning optimization signal, an active interference monitoring model is constructed to determine the interference frequency range of the active interference signal, and the interference frequency range is stored in an interference frequency data group;

[0012] Step 5. Based on the interference frequency data group, the navigation device adjusts the interference frequency range, performs data analysis on the telegram data group generated after the adjustment, obtains the frequency band available value Ky, and determines whether the positioning signal sent by the current satellite is available. If the positioning signal sent by the current satellite is available, the frequency band available value Ky is continuously monitored. If it is not available, the unavailable frequency band is marked, and the positioning signal of the navigation device is continued to be adjusted to the available frequency band.

[0013] In a second aspect, the present invention provides a positioning system for active interference of navigation signals in a complex site environment, comprising:

[0014] Telegram acquisition module: obtains satellite messages sent by positioning satellites and stores the satellite messages in a message data group;

[0015] Interference judgment module: Based on the message data group, the probability distribution of the empty string in the message data group is calculated to obtain the Poisson distribution probability P(k) of the average length of the null value run k, and judge whether there is interference with the navigation signal;

[0016] Optimization judgment module: If there is interference in the navigation signal, the adjustment time range is determined based on the time length corresponding to the maximum length of the "empty" run in the test data sequence Y and the time length corresponding to the fixed sampling period. Based on the adjustment time range, the fixed sampling period is adjusted to obtain the Poisson distribution probability P(x) of the average length x of the empty value run after each adjustment. If the Poisson distribution probability P(k) of the average length k of the empty value run after adjustment is higher than the probability threshold, a positioning optimization signal is generated;

[0017] Frequency band determination module: Based on the positioning optimization signal, an active interference monitoring model is constructed to determine the interference frequency range of the active interference signal, and the interference frequency range is stored in the interference frequency data group;

[0018] Control and optimization module: Based on the interference frequency data group, the navigation device adjusts the interference frequency range, performs data analysis on the telegram data group generated after the adjustment, obtains the frequency band available value Ky, and determines whether the positioning signal sent by the current satellite is available. If the positioning signal sent by the current satellite is available, the frequency band available value Ky is continuously monitored. If it is not available, the unavailable frequency band is marked, and the positioning signal of the navigation device continues to be adjusted to the available frequency band.

[0019] Beneficial effects of the present invention:

[0020] 1. By constructing an active interference monitoring model, the signal asymptotic ratio, message completeness ratio and Poisson distribution probability of the average length of null value runs are comprehensively considered to conduct detailed monitoring and analysis of the receiving frequency range of the navigation equipment. Compared with traditional methods, it can more effectively identify interference signals and avoid positioning errors caused by interference. For example, in complex terrain environments such as urban high-rise buildings or mountainous areas, it can effectively reduce the impact of active interference, provide a stable and reliable signal reception basis for navigation equipment, and significantly improve the accuracy of navigation positioning.

[0021] 2. Based on the in-depth analysis of the telegram data within the frequency receiving range after adjustment, including the incomplete telegram ratio and the Poisson distribution probability index of the average length of the null value run, it is judged whether the frequency band is available. If it is detected that the current frequency band is seriously interfered and unavailable, it can be switched to other available frequency bands to ensure that the navigation equipment always maintains a good working condition, which can reduce the risk of navigation failure caused by frequency band interference and improve the adaptability of the navigation system in complex interference environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 It is a flow chart of a method for locating active interference of navigation signals in a complex site environment provided by the present invention;

[0024] Figure 2 It is a structural schematic diagram of a positioning system for active interference of navigation signals in a complex site environment provided by Embodiment 3 of the present invention;

[0025] Figure 3 is a schematic diagram of the structure of a computer device provided in Embodiment 4 of the present invention; DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme 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 only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention. Embodiment 1

[0027] Figure 1 The present invention provides a flowchart of a method for locating active interference of navigation signals in a complex site environment. The embodiment of the present invention is applicable to the situation of active interference positioning. The active interference positioning method can be executed by an active interference positioning system. The positioning system for active interference of navigation signals in a complex site environment can be implemented by software and / or hardware. The positioning system for active interference of navigation signals in a complex site environment can be configured in a computer device. Optionally, the computer device can be an electronic device, which can be a notebook, a desktop computer, a smart tablet, etc., and the embodiment of the present invention does not limit this.

[0028] like Figure 1 As shown, an embodiment of the present invention provides a method for locating active interference of navigation signals in a complex site environment, which specifically includes the following steps:

[0029] Step 1: Obtain satellite messages sent by positioning satellites and store the satellite messages in a message data group;

[0030] In some embodiments, the navigation device receives satellite message data sent by the positioning satellite according to a fixed sampling period, wherein the satellite message data includes: satellite ephemeris, ionospheric model coefficients, status information, time information, etc.;

[0031] It should be noted that after receiving the satellite message data, the navigation device extracts the satellite ephemeris and time information in the satellite message data to determine the location of the device;

[0032] Obtain satellite message data of multiple fixed sampling periods, store the received satellite message data in a message data group in the time sequence of the fixed sampling periods, and if the navigation device does not receive a satellite message within the fixed sampling period, store an empty string in the corresponding position of the message data group;

[0033] It should be noted that the fixed sampling period is matched with the transmission period of the satellite message;

[0034] Step 2: Based on the message data group, the probability distribution of the empty character string in the message data group is calculated to obtain the Poisson distribution probability P(k) of the average length of the null value run k, and determine whether there is interference with the navigation signal;

[0035] Based on the telegram data group, the number of empty character strings in the telegram data group is obtained to obtain the number of empty value telegrams;

[0036] The total number of data in the telegram data group is obtained, and the number of null-value telegrams is processed by ratio processing with the total number of data in the telegram data group to obtain a null-value telegram ratio, and the null-value telegram ratio is marked as Kz;

[0037] The null value message distribution model is constructed using the run test method to determine the Poisson distribution probability P(k) of the null value run with an average length k.

[0038] The specific method of constructing the null value message distribution model is as follows:

[0039] S1. Classify and mark the satellite messages in the message data group, mark the data with empty value string as "empty", otherwise mark it as "non-empty", and construct a test data sequence Y containing "empty" and "non-empty" based on the message data group after classification and marking;

[0040] Exemplarily, the test data sequence Y=[“non-empty”, “non-empty”, “empty”, “empty”, “empty”, “non-empty”], wherein each “empty” and “non-empty” mark corresponds one-to-one to the satellite message data in the message data group;

[0041] S2. Count the lengths of all runs in the test data sequence Y. A run refers to a sequence segment of the same mark that appears continuously, that is, "empty" or "non-empty". The number of "empty" or "non-empty" sequence segments in a run is marked as the length of a run.

[0042] Exemplarily, in the above test data sequence Y, there is 1 run, which is a "non-empty" run of length 2, a "empty" run of length 3, and a "non-empty" run of length 1;

[0043] S3, sum and average the lengths of all runs containing "null" to obtain the average length of null runs k, and mark the total number of data in the test data sequence Y as n;

[0044] Based on the average length of null value runs k, the null value message ratio Kz, and the total number of data in the test data sequence Y, calculate the Poisson distribution probability P(k) of the average length of null value runs k;

[0045] By formula: Get the Poisson distribution probability P(k) of the average length of null value run k, where is an exponential function with base e, k! is the factorial of the average length of the null run k;

[0046] Compare the Poisson distribution probability P(k) of the average length k of the null value run with the probability threshold to determine whether there is interference with the navigation signal;

[0047] If the Poisson distribution probability P(k) of the average length k of the null value run is higher than the probability threshold, it means that the distribution of the empty character string in the message data group is higher than expected, and it is determined that there is interference in the navigation signal;

[0048] If the Poisson distribution probability P(k) of the average length k of the null value run is lower than the probability threshold, it indicates that the distribution of the empty character string in the message data group is within the expected range, and it is determined that there is no interference with the navigation signal;

[0049] It should be noted that, under ideal conditions without interference, the navigation signal is stable, the satellite message is transmitted normally, the null value appears randomly and relatively infrequently, and the Poisson distribution probability P(k) corresponding to the average length k of the null value run should be at a low level and relatively stable, which conforms to the law of null value appearance under normal communication environment. Under normal circumstances, the probability of null value appearance caused by various accidental factors is relatively small, and there will not be a large number of continuous null values, that is, the null value run will not be too long, so the calculated Poisson distribution probability P(k) is low;

[0050] If there is interference in the navigation signal, the satellite message will be lost or received incorrectly, which will change the frequency and length distribution of null values. For example, interference may cause the loss of continuous satellite messages, resulting in a longer null run, thereby increasing the average length k of the null run. According to the characteristics of Poisson distribution, when k increases, the calculated Poisson distribution probability P (k) will increase significantly.

[0051] The technical solution of this embodiment is: obtaining a satellite message sent by a positioning satellite, storing the satellite message in a message data group, and performing probability distribution calculation on an empty string in the message data group based on the message data group to obtain a Poisson distribution probability P(k) with an average length k of a null value run, and judging whether there is interference with the navigation signal. By judging the navigation interference, a basis is provided for subsequent optimization of the interference signal control. Embodiment 2

[0052] Step 3: If there is interference in the navigation signal, determine the adjustment time range based on the time length corresponding to the maximum length of the "empty" run in the test data sequence Y and the time length corresponding to the fixed sampling period. Based on the adjustment time range, adjust the fixed sampling period to obtain the Poisson distribution probability P(x) of the average length x of the empty value run after each adjustment. If the Poisson distribution probability P(k) of the average length k of the empty value run after adjustment is higher than the probability threshold, generate a positioning optimization signal.

[0053] If there is interference in the navigation signal, obtain the time length corresponding to the maximum value of the length of the "empty" run in the inspection data sequence Y, obtain the time length corresponding to the maximum value of the length of the "empty" run, and obtain the upper limit value of the adjustment time;

[0054] It should be noted that, since a fixed sampling period is used to sample the satellite message sent by the positioning satellite to obtain a message data group, and the message data group corresponds to the test data sequence Y one by one, the upper limit value of the adjustment time is obtained by multiplying the fixed sampling period by the maximum value of the length of the "empty" run;

[0055] The time corresponding to the fixed sampling period is used as the lower limit of the adjustment time, and the adjustment time range is constructed based on the upper limit of the adjustment time;

[0056] The fixed sampling period is used as the minimum adjustment unit of the adjustment time. Each time the time is adjusted, the fixed sampling period is accumulated according to the minimum adjustment unit until the upper limit of the adjustment time range is reached;

[0057] Based on the adjustment time range, the fixed sampling period is adjusted to obtain the Poisson distribution probability P(x) of the average length x of the null value run after each adjustment;

[0058] If the Poisson distribution probability P(k) of the average length k of the null value run after regulation is lower than the probability threshold, it indicates that the interference of the navigation equipment after regulation has been alleviated;

[0059] If the Poisson distribution probability P(k) of the average length k of the null value run after regulation is higher than the probability threshold, it indicates that the interference of the navigation equipment after regulation has not been alleviated, and a positioning optimization signal is generated to optimize the positioning of the navigation equipment;

[0060] It should be noted that due to signal interference, if the radio frequency of the interference signal is close to the frequency of the satellite message signal, signal blocking will occur in space, causing the navigation device to receive mainly the interference signal within a fixed sampling interval, resulting in the navigation device being unable to receive the satellite message;

[0061] Step 4: Based on the positioning optimization signal, an active interference monitoring model is constructed to determine the interference frequency range of the active interference signal, and the interference frequency range is stored in an interference frequency data group;

[0062] Based on the positioning optimization signal, the time range is adjusted as a monitoring dwell period;

[0063] In some embodiments, using a frequency synthesizer of the navigation device, adjusting the frequency of a radio signal received by the navigation device;

[0064] Constructing an active interference monitoring model, determining the interference frequency range of the active interference signal, and storing the interference frequency range in an interference frequency data group;

[0065] The specific construction method of the active interference monitoring model is as follows:

[0066] A1. Obtain the frequency receiving range of the current signal of the navigation device as the frequency monitoring range, establish a sliding monitoring block, the range of the sliding monitoring block is 1 / 4 of the frequency monitoring range, and monitor the received navigation signal strength and telegram data group in the sliding monitoring block according to the monitoring dwell period;

[0067] A2. In the sliding monitoring block, the navigation signal strength during the monitoring dwell period is numerically analyzed to obtain the signal asymptotic ratio Xj, the message data group during the monitoring dwell period is subjected to CRC-cyclic redundancy check, the distribution of the complete message data in the message data group is determined, the complete message ratio Wz is obtained, the Poisson distribution probability P(x) of the average length x of the null value run during the monitoring dwell period is obtained, and the active interference value Yg is calculated;

[0068] Obtain the navigation signal strength at the start time endpoint and the end time endpoint of the monitoring stop period in the sliding monitoring block;

[0069] Performing difference processing on the navigation signal strength at the start time endpoint and the navigation signal strength at the end time endpoint to obtain the navigation signal difference;

[0070] The navigation signal difference is processed by ratio with the navigation signal strength at the start time endpoint to obtain the signal asymptotic ratio, and the signal asymptotic ratio is marked as Xj;

[0071] Obtain the message data of non-empty character strings in the message data group, and use CRC-cyclic redundancy check to perform integrity analysis on the message data;

[0072] It should be noted that when sending data, the satellite message will generate a checksum according to a certain algorithm, such as CRC-cyclic redundancy check, and append it to the end of the data. The navigation device, as the receiving end, uses the same algorithm to recalculate the checksum of the received data, and then compares it with the received checksum. If the two are consistent, it means that there may be no error in the data transmission process. If they are inconsistent, it means that the data is wrong or tampered with, and the data integrity is damaged. For example, for a message data with a length of n bytes, the receiving device can calculate its checksum according to the CRC-16 algorithm, and then compare it with the received 16-bit checksum;

[0073] Marking incomplete telegram data in the telegram data group as incomplete telegram data;

[0074] Marking the complete telegram data in the telegram data group as complete telegram data;

[0075] Get the number of complete telegram data and the number of telegram data with non-empty character strings in the telegram data group;

[0076] The number of complete telegram data is processed by ratio with the number of telegram data of non-empty character strings in the telegram data group to obtain a complete data ratio, and the complete data ratio is marked as Wz;

[0077] Get the Poisson distribution probability P(x) of the average length x of the null value run in the telegram data set obtained in the sliding monitoring block

[0078] Based on the complete data ratio Wz, the Poisson distribution probability P(x) of the average length of the null value run x, and the signal asymptotic ratio Xj, the active interference value Yg is calculated;

[0079] By formula: Get the active interference value Yg, a=0.125, b=0.541, c=0.312;

[0080] A3. The sliding monitoring block moves toward the maximum endpoint value of the frequency monitoring range according to the length of the sliding monitoring block until the maximum endpoint value of the sliding monitoring block reaches the maximum endpoint value of the frequency monitoring range, and the active interference value Yg of all sliding monitoring blocks is obtained within the frequency monitoring range. The midpoint value of the frequency range of the sliding monitoring block is obtained as the midpoint frequency, and the midpoint frequency and the active interference value Yg are used as a data pair to construct a midpoint frequency-interference value set;

[0081] Exemplarily, within the frequency monitoring range, according to the division method of the sliding monitoring block, that is, the range of the sliding monitoring block is 1 / 4 of the frequency monitoring range, the frequency range of each sliding monitoring block is determined in turn. For example, the frequency monitoring range is 1000MHz-1200MHz. If the sliding monitoring block range is 50MHz, the frequency range of the first block is 1000MHz-1050MHz, and the corresponding midpoint frequency is (1000+1050) / 2=1025MHz;

[0082] For each sliding monitoring block, the active interference value Yg is obtained, and the midpoint frequency and the corresponding active interference value Yg are combined into a data pair;

[0083] The midpoint frequency is labeled as f i , construct data pairs (f i ,Yg i ), for example (1025MHz, 0.3);

[0084] All data pairs are aggregated to form a midpoint frequency-interference value set G i , G i ={(1025MHz,0.3),(1075MHz,0.4),...,(1125MHz,0.2)}, where i represents the number of the data pair, i=1,2,...,n, n is the total number of data pairs, Yg irepresents the interference value in each data pair;

[0085] It should be noted that the midpoint frequency value is the frequency range that characterizes the sliding monitoring block;

[0086] A4. Use the maximum likelihood estimation method to fit the data pairs in the midpoint frequency-interference value set, and judge the convergence of the fitting results. If converged, the frequency range corresponding to the range of (μ-2σ, μ+2σ) is used as the interference frequency range of the interference source. If not converged, continue to adjust the range of the sliding monitoring block to 1 / 10 of the original;

[0087] Specifically, using the likelihood function , , where μ1 and σ1 are the midpoint frequency-interference value set G i The mean and standard deviation of Yg i represents the interference value in each data pair, is the exponential function of base e;

[0088] Use the gradient descent method to maximize the likelihood function, through the formula: , Get the updated μ and σ, where α is the learning rate, α=0.01, , is the mean and standard deviation of the next data pair, is the partial derivative of the likelihood function;

[0089] Determine the result of maximizing the likelihood function fitting, if , the fitting result is considered to be converged, otherwise continue to adjust the range of the sliding monitoring block to 1 / 10 of the original;

[0090] It should be noted that It is set by professionals in this field based on their experience;

[0091] A5. Place the sliding monitoring block within the frequency monitoring range and put the monitored interference frequency range into the interference frequency data group;

[0092] Step 5: Based on the interference frequency data group, the navigation device adjusts the interference frequency range, performs data analysis on the message data group generated after the adjustment, obtains the frequency band available value Ky, and determines whether the positioning signal sent by the current satellite is available. If the positioning signal sent by the current satellite is available, the frequency band available value Ky is continuously monitored. If it is not available, the unavailable frequency band is marked, and the positioning signal of the navigation device is continuously adjusted to the available frequency band.

[0093] Obtaining an interference frequency range in an interference frequency data group, and using a frequency synthesizer in a navigation device to adjust a frequency receiving range so that the interference frequency range is not within the adjusted frequency receiving range;

[0094] The adjusted frequency receiving range is marked as an adjusted receiving frequency;

[0095] Based on the adjusted receiving frequency, obtaining the telegram data group received within the adjusted receiving frequency, and obtaining the incomplete telegram data in the telegram data group;

[0096] Obtain the number of incomplete telegram data in the telegram data group, perform ratio processing on the number of incomplete telegram data in the telegram data group and the number of telegram data of non-empty character strings in the telegram data group to obtain an incomplete telegram ratio, and mark the incomplete telegram ratio as Cq;

[0097] Obtain the Poisson distribution probability P(x) of the average length x of the null value run that adjusts the receiving frequency;

[0098] Based on the Poisson distribution probability P(x) of the incomplete message ratio Cq and the average length x of the null value run, the available value Ky of the frequency band is calculated;

[0099] By formula: Get the available value Ky of the frequency band, where d=1.25 and h=0.86;

[0100] Compare the frequency band available value Ky with the frequency band available threshold to determine whether the positioning signal sent by the current satellite is available;

[0101] If the frequency band available value Ky is higher than the frequency band available threshold, it indicates that the interference signal to the current satellite's transmission frequency band is within expectations, and the positioning signal sent by the current satellite is available, but it is still necessary to continue to monitor the change of the frequency band available value Ky;

[0102] If the frequency band available value Ky is lower than the frequency band available threshold, it indicates that the current satellite's sending frequency band is seriously interfered by the interference signal, that is, the positioning signal sent by the current satellite is unavailable, and the satellite's current sending frequency band is marked as an unavailable frequency band;

[0103] The navigation device sends the unavailable frequency band to the system to inform other navigation devices in the surrounding area of ​​the unavailable frequency band;

[0104] The navigation device obtains different frequency bands sent by the positioning satellite and adjusts the receiving frequency to the different frequency bands sent by the positioning satellite to determine whether there is interference with the navigation signal of the frequency band;

[0105] If there is interference, continue to analyze, determine the available value Ky of the frequency band, and mark the unavailable frequency band until the navigation device obtains an available frequency band;

[0106] It should be noted that the available frequency band refers to the Poisson distribution probability P(k) of the average length k of the null value run being lower than the probability threshold, indicating that the distribution of the empty character string in the message data group is within the expected range, and it is determined that there is no interference with the navigation signal, and the frequency band transmitted by the positioning satellite is available;

[0107] The technical solution of this embodiment is: if there is interference in the navigation signal, based on the time length corresponding to the maximum length of the "empty" run in the test data sequence Y and the time length corresponding to the fixed sampling period, the adjustment time range is determined, and the fixed sampling period is adjusted based on the adjustment time range to obtain the Poisson distribution probability P(x) of the average length x of the empty value run after each adjustment, if the Poisson distribution probability P(k) of the average length k of the empty value run after adjustment is higher than the probability threshold, a positioning optimization signal is generated, based on the positioning optimization signal, an active interference monitoring model is constructed, the interference frequency range of the active interference signal is determined, the interference frequency range is stored in the interference frequency data group, and based on the interference frequency data group, the navigation device adjusts the interference frequency range, and generates The telegram data group is analyzed to obtain the frequency band available value Ky, and it is determined whether the positioning signal sent by the current satellite is available. If the positioning signal sent by the current satellite is available, the frequency band available value Ky is continuously monitored. If it is not available, the unavailable frequency band is marked, and the positioning signal of the navigation device is continued to be adjusted to the available frequency band. Based on the in-depth analysis of the telegram data within the adjusted frequency receiving range, including the incomplete telegram ratio and the Poisson distribution probability index of the average length of the null value run, it is determined whether the frequency band is available. If it is detected that the current frequency band is seriously interfered and unavailable, the navigation device is switched to other available frequency bands to ensure that the navigation device always maintains a good working state, which can reduce the risk of navigation failure caused by frequency band interference and improve the adaptability of the navigation system in complex interference environments. Embodiment 3

[0108] A positioning system for active interference of navigation signals in a complex site environment, comprising:

[0109] Telegram acquisition module: obtains satellite messages sent by positioning satellites and stores the satellite messages in a message data group;

[0110] Interference judgment module: Based on the message data group, the probability distribution of the empty string in the message data group is calculated to obtain the Poisson distribution probability P(k) of the average length of the null value run k, and judge whether there is interference with the navigation signal;

[0111] Optimization judgment module: If there is interference in the navigation signal, the adjustment time range is determined based on the time length corresponding to the maximum length of the "empty" run in the test data sequence Y and the time length corresponding to the fixed sampling period. Based on the adjustment time range, the fixed sampling period is adjusted to obtain the Poisson distribution probability P(x) of the average length x of the empty value run after each adjustment. If the Poisson distribution probability P(k) of the average length k of the empty value run after adjustment is higher than the probability threshold, a positioning optimization signal is generated;

[0112] Frequency band determination module: Based on the positioning optimization signal, an active interference monitoring model is constructed to determine the interference frequency range of the active interference signal, and the interference frequency range is stored in the interference frequency data group;

[0113] Control and optimization module: Based on the interference frequency data group, the navigation device adjusts the interference frequency range, performs data analysis on the message data group generated after the adjustment, obtains the frequency band available value Ky, and determines whether the positioning signal sent by the current satellite is available. If the positioning signal sent by the current satellite is available, the frequency band available value Ky is continuously monitored. If it is not available, the unavailable frequency band is marked, and the positioning signal of the navigation device is continuously adjusted to the available frequency band. Embodiment 4

[0114] Reference Figure 3 The embodiment of the present invention further provides a computer device 3, comprising: a memory 302 and a processor 301 and a computer program 303 stored in the memory 302. When the computer program 303 is executed on the processor 301, a method for locating active interference of navigation signals in a complex site environment as described in any one of the above methods is implemented.

[0115] The computer device 3 may be a computing device such as a desktop computer, a notebook, a PDA, a cloud server, etc. The computer device 3 may include, but is not limited to, a processor 301 and a memory 302. Those skilled in the art may understand that;

[0116] Figure 3 It is only an example of computer device 3 and does not constitute a limitation on computer device 3. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components, for example, it may also include input and output devices, network access devices, etc.

[0117] The processor 301 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0118] In some embodiments, the memory 302 may be an internal storage unit of the computer device 3, such as a hard disk or memory of the computer device 3. In other embodiments, the memory 302 may also be an external storage device of the computer device 3, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the computer device 3. Further, the memory 302 may also include both an internal storage unit and an external storage device of the computer device 3. The memory 302 is used to store an operating system, an application program, a boot loader (BootLoader), data, and other programs, such as the program code of the computer program. The memory 302 may also be used to temporarily store data that has been output or is to be output. Embodiment 5

[0119] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for locating active interference of navigation signals in a complex site environment as described in any one of the above methods is implemented.

[0120] In this embodiment, if the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, which can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above-mentioned various method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium can at least include: any entity or device that can carry the computer program code to the camera / terminal device, recording medium, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. For example, USB flash drive, mobile hard disk, disk or optical disk. In some jurisdictions, according to legislation and patent practice, computer-readable media cannot be electric carrier signals and telecommunication signals.

[0121] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0122] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0123] In the embodiments disclosed in the present application, it should be understood that the disclosed apparatus / terminal equipment and method can be implemented in other ways. For example, the apparatus / terminal equipment embodiments described above are merely illustrative. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0124] One point, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, which may be electrical, mechanical or other forms.

[0125] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0126] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0127] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A method for locating active interference of navigation signals in a complex site environment, characterized in that: The following steps are involved: Step 1: Obtain satellite messages sent by positioning satellites and store the satellite messages in a message data group; Step 2: Based on the message data group, the probability distribution of the empty character string in the message data group is calculated to obtain the Poisson distribution probability P(k) of the average length of the null value run k, and determine whether there is interference with the navigation signal; Step 3: If there is interference in the navigation signal, determine the adjustment time range based on the time length corresponding to the maximum length of the "empty" run in the test data sequence Y and the time length corresponding to the fixed sampling period. Based on the adjustment time range, adjust the fixed sampling period to obtain the Poisson distribution probability P(x) of the average length x of the empty value run after each adjustment. If the Poisson distribution probability P(k) of the average length k of the empty value run after adjustment is higher than the probability threshold, generate a positioning optimization signal. Step 4: Based on the positioning optimization signal, an active interference monitoring model is constructed to determine the interference frequency range of the active interference signal, and the interference frequency range is stored in an interference frequency data group; Step 5. Based on the interference frequency data group, the navigation device adjusts the interference frequency range, performs data analysis on the telegram data group generated after the adjustment, obtains the frequency band available value Ky, and determines whether the positioning signal sent by the current satellite is available. If the positioning signal sent by the current satellite is available, the frequency band available value Ky is continuously monitored. If it is not available, the unavailable frequency band is marked, and the positioning signal of the navigation device is continued to be adjusted to the available frequency band.

2. According to claim 1, a method for locating active interference of navigation signals in a complex site environment is characterized in that: The method of calculating the probability distribution of the empty character string in the telegram data group is as follows: Based on the telegram data group, the number of empty character strings in the telegram data group is obtained to obtain the number of empty value telegrams; The total number of data in the telegram data group is obtained, and the number of null-value telegrams is processed by ratio processing with the total number of data in the telegram data group to obtain a null-value telegram ratio, and the null-value telegram ratio is marked as Kz; The null value message distribution model is constructed using the runs test method to determine the Poisson distribution probability P(k) of the null value run with an average length k.

3. The method for locating active interference of navigation signals in a complex site environment according to claim 2 is characterized in that: The Poisson distribution probability P(k) of the null value run with an average length k is obtained as follows: The null value message distribution model is constructed using the run test method to determine the Poisson distribution probability P(k) of the null value run with an average length k. Based on the average length of null value runs k, the null value message ratio Kz, and the total number of data in the test data sequence Y, calculate the Poisson distribution probability P(k) of the average length of null value runs k; By formula: Get the Poisson distribution probability P(k) of the average length of null value run k, where is an exponential function with base e, k! is the factorial of the average length of the null run k; If the Poisson distribution probability P(k) of the average length k of the null value run is higher than the probability threshold, it is determined that there is interference in the navigation signal.

4. According to claim 1, the method for locating active interference of navigation signals in a complex site environment is characterized in that: The positioning optimization signal is generated in the following manner: If there is interference in the navigation signal, obtain the time length corresponding to the maximum value of the length of the "empty" run in the inspection data sequence Y, obtain the time length corresponding to the maximum value of the length of the "empty" run, and obtain the upper limit value of the adjustment time; The time corresponding to the fixed sampling period is used as the lower limit of the adjustment time, and the adjustment time range is constructed based on the upper limit of the adjustment time; The fixed sampling period is used as the minimum adjustment unit of the adjustment time. Each time the time is adjusted, the fixed sampling period is accumulated according to the minimum adjustment unit until the upper limit of the adjustment time range is reached; Based on the adjustment time range, the fixed sampling period is adjusted to obtain the Poisson distribution probability P(x) of the average length x of the null value run after each adjustment; If the Poisson distribution probability P(k) of the average length k of the null value run after regulation is higher than the probability threshold, a positioning optimization signal is generated.

5. The method for locating active interference of navigation signals in a complex site environment according to claim 1, characterized in that: The interference frequency range of the active interference signal is determined as follows: Based on the positioning optimization signal, the time range is adjusted as a monitoring dwell period; Constructing an active interference monitoring model, determining the interference frequency range of the active interference signal, and storing the interference frequency range in an interference frequency data group; The specific construction method of the active interference monitoring model is as follows: A1. Obtain the frequency receiving range of the current signal of the navigation device as the frequency monitoring range, establish a sliding monitoring block, and monitor the received navigation signal strength and telegram data group in the sliding monitoring block; A2. In the sliding monitoring block, the navigation signal strength during the monitoring dwell period is numerically analyzed to obtain the signal asymptotic ratio Xj, the message data group during the monitoring dwell period is CRC-cyclic redundancy check to obtain the complete message ratio Wz, the Poisson distribution probability P(x) of the average length x of the null value run during the monitoring dwell period is obtained, and the active interference value Yg is calculated; A3. Move the sliding monitoring block within the frequency monitoring range, obtain the active interference value Yg of all sliding monitoring blocks within the frequency monitoring range, obtain the midpoint value of the frequency range of the sliding monitoring block as the midpoint frequency, use the midpoint frequency and the active interference value Yg as a data pair, and construct a midpoint frequency-interference value set; A4. Fit the data pairs in the midpoint frequency-interference value set using the maximum likelihood estimation method, and judge the convergence of the fitting results. If converged, the frequency range corresponding to the range of (μ-2σ, μ+2σ) is used as the interference frequency range of the interference source. If not converged, continue to adjust the range of the sliding monitoring block; A5. Place the sliding monitoring block within the frequency monitoring range and put the monitored interference frequency range into the interference frequency data group.

6. The method for locating active interference of navigation signals in a complex site environment according to claim 5, characterized in that: The active interference value Yg is obtained as follows: Obtain the navigation signal strength at the start time endpoint and the end time endpoint of the monitoring stop period in the sliding monitoring block; Performing difference processing on the navigation signal strength at the start time endpoint and the navigation signal strength at the end time endpoint to obtain the navigation signal difference; The navigation signal difference is processed by ratio with the navigation signal strength at the start time endpoint to obtain the signal asymptotic ratio, and the signal asymptotic ratio is marked as Xj; The telegram data of the telegram data group are analyzed to obtain the Poisson distribution probability P(x) of the complete data ratio Wz and the null value run length x; Based on the complete data ratio Wz, the Poisson distribution probability P(x) of the average length of the null value run x, and the signal asymptotic ratio Xj, the active interference value Yg is calculated; By formula: Get the active interference value Yg, where a, b, and c are preset proportional coefficients.

7. The method for locating active interference of navigation signals in a complex site environment according to claim 6, characterized in that: The message data of the message data group are analyzed to obtain the Poisson distribution probability P(x) of the complete data ratio Wz and the null value run length x as follows: Obtain the message data of non-empty character strings in the message data group, and use CRC-cyclic redundancy check to perform integrity analysis on the message data; Marking incomplete telegram data in the telegram data group as incomplete telegram data; Marking the complete telegram data in the telegram data group as complete telegram data; Get the number of complete telegram data and the number of telegram data with non-empty character strings in the telegram data group; The number of complete telegram data is processed by ratio with the number of telegram data of non-empty character strings in the telegram data group to obtain a complete data ratio, and the complete data ratio is marked as Wz; Obtain the Poisson distribution probability P(x) of the average length x of the null value run in the telegram data group obtained in the sliding monitoring block.

8. The method for locating active interference of navigation signals in a complex site environment according to claim 5, characterized in that: The maximum likelihood estimation method is fitted in the following way: Building the likelihood function And perform fitting to determine the result of maximizing the likelihood function fitting. If , the fitting result is considered to have converged, otherwise the range of the sliding monitoring block continues to be adjusted.

9. The method for locating active interference of navigation signals in a complex site environment according to claim 1, characterized in that: The method for determining whether the positioning signal sent by the current satellite is available is: If the frequency band available value Ky is higher than the frequency band available threshold, the positioning signal sent by the current satellite is available; If the frequency band available value Ky is lower than the frequency band available threshold, the positioning signal currently sent by the satellite is unavailable, and the satellite's current sending frequency band is marked as an unavailable frequency band; The navigation device obtains different frequency bands sent by the positioning satellite and adjusts the receiving frequency to the different frequency bands sent by the positioning satellite to determine whether there is interference with the navigation signal of the frequency band; If there is interference, continue to analyze, determine the available value Ky of the frequency band, and mark the unavailable frequency band until the navigation device obtains an available frequency band.

10. The method for locating active interference of navigation signals in a complex site environment according to claim 9, characterized in that: The frequency band available value Ky is obtained as follows: Adjust the frequency receiving range so that the interference frequency range is not within the adjusted frequency receiving range; The adjusted frequency receiving range is marked as an adjusted receiving frequency; Obtaining incomplete message data in the message data group; Obtain the number of incomplete telegram data in the telegram data group, perform ratio processing on the number of incomplete telegram data in the telegram data group and the number of telegram data of non-empty character strings in the telegram data group to obtain an incomplete telegram ratio, and mark the incomplete telegram ratio as Cq; Obtain the Poisson distribution probability P(x) of the average length x of the null value run that adjusts the receiving frequency; Based on the Poisson distribution probability P(x) of the incomplete message ratio Cq and the average length x of the null value run, the available value Ky of the frequency band is calculated; By formula: Get the available value Ky of the frequency band, where d and h are preset proportional coefficients.

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