Detection and suppression method for suppressing deception combination interference of high-precision anti-interference navigation

Abstract

The invention relates to the technical field of high-precision anti-interference satellite navigation, and particularly discloses a detection and suppression method for suppressing deception combination interference of high-precision anti-interference navigation. One or at least two of space-frequency joint-multi-beam / zeroing-noise subspace projection, correlation peak detection and screening, true convex false deception jamming suppression detection, deception jamming recovery and cancellation, improved PAC and dense suppression / isolated suppression deception / dense suppression deception jamming subspace rapid solving methods are adopted for deep fusion; detection and suppression of combined interference are realized. According to the method, the problems of detection and suppression of combined interference of isolated suppression and weak cheating, dense suppression and weak cheating, isolated suppression and stronger cheating, dense suppression and stronger cheating, isolated suppression and strong cheating, dense suppression and strong cheating and the like are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of high-precision anti-interference satellite navigation, and in particular to a method for detecting and suppressing suppression deception combined interference of high-precision anti-interference navigation. Background Art

[0002] The outstanding features of high-precision anti-interference satellite navigation applications such as precision approach and landing of aircraft, landing of aircraft on aircraft carriers, formation flying and automatic aerial refueling, rapid direction finding and autonomous north seeking of missile launchers / aircraft are complex interference environments and high requirements for positioning and orientation.

[0003] The complexity of the interference environment is mainly manifested in the variety of interference types and changes. From the perspective of interference mechanism, the interference types are divided into suppression interference, deception interference, and suppression and deception combined interference. Deception interference is further divided into regeneration and forwarding types. Interference changes mainly include the number, direction, modulation, frequency, intensity, etc. of interference that changes rapidly or slowly over time. Positioning and orientation requirements include real-time or near real-time positioning services at the decimeter / centimeter level and orientation services better than 1 degree / 0.5 degree.

[0004] High-precision positioning and orientation in complex interference environments requires solving three strongly coupled problems: complex interference detection and real-time suppression, satellite signal distortion tracing and control, and high-precision positioning and orientation with low distortion.

[0005] Through theoretical deduction, simulation analysis and experimental verification, the inventors decoupled the above three problems into three categories, seven subcategories and 10 sequential topics as shown in the table below.

[0006] Based on this, 10 high-precision anti-interference navigation invention patents corresponding to the above topics are planned and laid out, as shown in Table 1.

[0007] Table 1 List of decoupling and disassembly of high-precision positioning and orientation problems in complex interference environments

[0008] In the present invention, the first category, the third subcategory, and the fifth invention listed in Table 1 - the detection and suppression method of the suppression deception combined interference of high-precision anti-interference navigation are analyzed and explained.

[0009] Suppression deception combined interference is composed of suppression interference and deception interference. Existing interference detection and suppression methods mainly include adaptive nulling anti-suppression interference based on array antenna, multi-beam anti-suppression interference method, deception interference suppression method based on narrow correlation, deception interference detection and suppression method based on correlation peak detection and screening, etc.

[0010] Combined interference can be subdivided into isolated suppression and weak deception combined interference, intensive suppression and weak deception combined interference, isolated suppression and relatively strong deception combined interference, intensive suppression and relatively strong deception combined interference, isolated suppression and strong deception combined interference, intensive suppression and strong deception combined interference, etc. Here, isolated interference and intensive interference are divided according to spatial distribution. Intensive interference means that many point interference sources are distributed in a small angular domain, and the spatial distribution is very close. More complex combined interference should be dealt with in conjunction with interference source positioning and orientation, radar detection and early warning, etc., which is not considered in the present invention.

[0011] Among the existing interference detection and suppression methods, adaptive zeroing anti-suppression interference and multi-beam anti-suppression interference based on array antenna are suitable for suppression interference and strong deception interference; deception interference suppression based on narrow correlation and deception interference detection and suppression based on correlation peak detection and screening are suitable for weak deception interference; none of them can detect and suppress the above six combined interferences.

[0012] Based on this technical background, the present invention studies the detection and suppression method of suppression deception combined interference for high-precision anti-interference navigation. Summary of the invention

[0013] In view of the shortcomings of the prior art, the present invention provides a method for detecting and suppressing deception combined interference for high-precision anti-interference navigation, deeply integrating space-frequency joint-multi-beam / zeroing-noise subspace projection, correlation peak detection and screening, true convex suppression and false deception interference detection, deception interference recovery and cancellation, improved PAC, interference subspace rapid solution and other methods, to achieve the detection and suppression of combined interference.

[0014] In order to achieve the above-mentioned objectives, the present invention provides a method for detecting and suppressing suppression deception combined interference of high-precision anti-interference navigation, including: for suppression deception combined interference, using space-frequency joint-multi-beam / zeroing-noise subspace projection, correlation peak detection and screening, true convex suppression and false deception interference detection, deception interference recovery cancellation, improved PAC, dense suppression / isolated suppression deception / dense suppression deception interference subspace rapid solution method or at least two of them for deep fusion to realize the detection and suppression of combined interference.

[0015] The beneficial effects of the present invention include: The method for detecting and suppressing suppression deception combined interference of high-precision anti-interference navigation proposed in the present invention deeply integrates the methods of space-frequency joint-multi-beam / zeroing-noise subspace projection, correlation peak detection and screening, true convex suppression and false deception interference detection, deception interference recovery cancellation, improved PAC, and interference subspace rapid solution; it systematically solves the detection and suppression problems of combined interference such as isolated suppression and weak deception, dense suppression and weak deception, isolated suppression and relatively strong deception, dense suppression and relatively strong deception, isolated suppression and strong deception, and dense suppression and strong deception.

[0016] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings.

[0018] Figure 1 It is a flow chart of the method for detecting and suppressing the combined interference of suppression deception for high-precision anti-interference navigation proposed by the present invention. DETAILED DESCRIPTION

[0019] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0020] The present invention provides a method for detecting and suppressing the combined interference of suppression deception in high-precision anti-interference navigation, such as Figure 1 As shown, including:

[0021] For suppression and deception combined interference, one or at least two of the following methods are deeply integrated: space-frequency joint-multi-beam / zeroing-noise subspace projection, correlation peak detection and screening, true convex suppression and false deception interference detection, deception interference recovery cancellation, improved PAC, dense suppression / isolated suppression deception / dense suppression deception interference subspace fast solution method to achieve detection and suppression of combined interference.

[0022] In the present invention, methods such as space-frequency joint-multi-beam / zeroing-noise subspace projection, correlation peak detection and screening, true convex suppression and false deception interference detection, deception interference recovery cancellation, improved PAC, and interference subspace fast solution are deeply integrated; the detection and suppression problems of combined interferences such as isolated suppression and weak deception, dense suppression and weak deception, isolated suppression and relatively strong deception, dense suppression and relatively strong deception, isolated suppression and strong deception, and dense suppression and strong deception are systematically solved.

[0023] According to the present invention, the suppression deception combination interference includes isolated suppression and weak deception combination interference, intensive suppression and weak deception combination interference, isolated suppression and relatively strong deception combination interference, intensive suppression and relatively strong deception combination interference, isolated suppression and strong deception combination interference and intensive suppression and strong deception combination interference;

[0024] For isolated suppression and weak deception combined interference, the space-frequency joint-multi-beam / zeroing-noise subspace projection and correlation peak detection and screening methods are deeply integrated to achieve detection and suppression of combined interference. Among them, the space-frequency joint-multi-beam / zeroing-noise subspace projection method is used to suppress isolated suppression interference, and the correlation peak detection and screening method is used to detect and suppress weak deception interference;

[0025] The space-frequency joint-multi-beam-noise subspace projection method is used when the satellite position, the phase center position of the array antenna, and the antenna array attitude are known, and includes the following steps:

[0026] Step 1: The spatial signal is received, amplified, down-converted, filtered, and processed by the antenna array element, RF channel, and analog-to-digital conversion unit in sequence, and then multiple digital intermediate frequency signals are output; each digital intermediate frequency signal is then divided into two paths after serial / parallel conversion and fast Fourier transform, one path is sent to the FIFO buffer, and the other path is sent to the weight vector calculation unit;

[0027] Step 2: The weight vector calculation unit uses multi-level Wiener filtering to perform forward decomposition to obtain the noise subspace and projection matrix;

[0028] Step 3: Multiply the L desired satellite steering vectors by the noise subspace projection matrix respectively, and normalize the multiplication results to obtain L optimal weight vectors for the array antenna beam to point to the L satellites respectively;

[0029] Step 4: Match the L optimal weight vectors with the weighted data in the FIFO cache and perform weighted summation to ensure that the null position and depth of the array antenna match the direction and strength of the interference, and at the same time ensure that the synthetic beam points to the desired satellite to achieve high-quality reception of the desired satellite signal.

[0030] According to the present invention, the space-frequency joint-zeroing-noise subspace projection method is used in the case where the satellite position, the phase center position of the array antenna, and the antenna array attitude are unknown, and includes the following steps:

[0031] The first step is the same as the first step of the space-frequency joint-multi-beam-noise subspace projection method;

[0032] Step 2: Same as the second step of the space-frequency joint-multi-beam-noise subspace projection method;

[0033] Step 3: Multiply the noise subspace projection matrix by a vector whose only first element is non-zero, and normalize the multiplication result to obtain an optimal weight vector for aligning the array antenna null with the interference direction;

[0034] Step 4: Match the optimal weight vector with the weighted data in the FIFO buffer and perform weighted summation to ensure that the null position and depth of the array antenna match the direction and strength of the interference.

[0035] Related peak detection and screening methods include:

[0036] 1) Mechanism and decision criteria of correlation peak detection:

[0037] Satellite signals use a direct sequence spread spectrum system, in which the spread spectrum sequence is a pseudo-random code sequence with sharp autocorrelation characteristics and flat cross-correlation characteristics. If there is weak deception interference, there will be more than one sharp correlation peak in the two-dimensional search space of pseudo-random code phase and Doppler frequency shift;

[0038] If the number of correlation peaks detected is 1, it is determined that there is no deceptive interference;

[0039] If the number of correlation peaks is greater than 1, it is determined that there is deceptive interference.

[0040] 2) Mechanism and processing method of relevant peak screening:

[0041] After deceptive interference is detected, that is, the number of correlation peaks is greater than 1, the deceptive interference, especially forwarding interference, usually lags behind the satellite signal.

[0042] The correlation peaks with earlier pseudo code delay are selected and transferred to the tracking stage; the correlation peaks with later pseudo code delay are discarded and not transferred to the tracking stage.

[0043] According to the present invention, for the combined interference of dense suppression and weak deception, the space-frequency joint-multi-beam / zeroing-noise subspace projection, the dense suppression interference subspace fast solution, and the correlation peak detection and screening method are deeply integrated to realize the detection and suppression of the combined interference, wherein the space-frequency joint-multi-beam / zeroing-noise subspace projection, the dense suppression interference subspace fast solution deep fusion method is used to suppress the dense suppression interference, and the correlation peak detection and screening method is used to detect and suppress the weak deception interference;

[0044] The steps of the space-frequency joint-multi-beam / zeroing-noise subspace projection and dense suppressed interference subspace fast solution deep fusion method are the same as the first, third and fourth steps of the space-frequency joint-multi-beam / zeroing-noise subspace projection method, with only the second step being different; the second step includes: using the dense suppressed interference subspace fast solution method to obtain the dense suppressed interference subspace, the noise subspace and the projection matrix, that is, first expanding the covariance matrix in the interference incident direction to obtain the expanded covariance matrix; then using a multi-level Wiener filter based on the covariance matrix hierarchy to forward decompose the expanded covariance matrix, quickly solve the dense suppressed interference subspace, and then obtain the noise subspace and the projection matrix.

[0045] According to the present invention, for isolated suppression and strong deception combined interference, if the direction of the deception interference is unknown, the space-frequency joint-multi-beam / zeroing-noise subspace projection is deeply integrated with the true convex false deception interference detection, deception interference recovery cancellation, and improved PAC method to achieve detection and suppression of combined interference; if the direction of the deception interference is known, the space-frequency joint-multi-beam / zeroing-noise subspace projection and the isolated suppression deception interference subspace fast solution are deeply integrated to achieve detection and suppression of combined interference;

[0046] Suppress true convex false deception interference detection, deception interference recovery cancellation, improved PAC method, including:

[0047] 1) Suppressing true convexity and false deception interference detection:

[0048] First, determine the visible satellite set according to the almanac and the approximate position, and select the satellite to be detected from the visible satellite set;

[0049] Then, a virtual medium-intensity interference is created in the direction of the signal from the satellite to be detected, and a virtual interference subspace and a noise subspace are obtained by a fast solution method of a virtual interference subspace, that is, according to the upward steering vector of the satellite to be detected and the anti-interference freedom degree of the array antenna, so that the array antenna forms a null in the direction of the satellite to be detected to suppress the signal of the satellite to be detected;

[0050] Finally, if the navigation processing unit can capture and track the satellite to be detected or the non-visible satellite, it is determined that there is deception interference; otherwise, it is determined that there is no deception interference;

[0051] 2) Deception jamming recovery cancellation, improved PAC:

[0052] Firstly, according to the deception interference detection situation, the amplitude and phase of the deception interference are estimated, and the deception interference is recovered;

[0053] This is then subtracted from the received signal, suppressing the spoofing jammer to below -10dB;

[0054] Finally, the improved PAC method is used, that is, a correlator search is added to the conventional PAC method. ~ The correlation peak in the chip area is used to correct the phase detection function and suppress residual deception interference.

[0055] The steps of the deep fusion method of space-frequency joint-multi-beam / zeroing-noise subspace projection and isolated suppression deception interference subspace rapid solution are the same as the first, third and fourth steps of the space-frequency joint-multi-beam / zeroing-noise subspace projection method, with only the second step being different; the second step: adopting the isolated suppression deception interference subspace rapid solution method to obtain the isolated suppression deception interference subspace, the noise subspace and the projection matrix, that is, adopting the multi-level Wiener filtering forward decomposition based on data hierarchy and the Schmidt orthogonalization of the deception interference guidance vector to quickly solve the isolated suppression deception interference subspace, and then obtain the noise subspace and the projection matrix.

[0056] According to the present invention, for the combined interference of dense suppression and relatively strong deception, if the direction of the deception interference is unknown, the space-frequency joint-multi-beam / zeroing-noise subspace projection and the dense suppression interference subspace are quickly solved, and are deeply integrated with the true convex false deception interference detection, deception interference recovery cancellation, and improved PAC to achieve the detection and suppression of the combined interference; if the direction of the deception interference is known, the space-frequency joint-multi-beam / zeroing-noise subspace projection and the dense suppression deception interference subspace are quickly solved to achieve the detection and suppression of the combined interference;

[0057] The steps of the deep fusion method of space-frequency joint-multi-beam / zeroing-noise subspace projection and dense suppression deception interference subspace rapid solution are the same as the first, third and fourth steps of the space-frequency joint-multi-beam / zeroing-noise subspace projection method, with only the second step being different; the second step includes: adopting the dense suppression deception interference subspace rapid solution method to obtain the dense suppression deception interference subspace, the noise subspace and the projection matrix, that is, adopting the multi-level Wiener filtering forward decomposition based on interference to the expanded covariance matrix hierarchy and the Schmidt orthogonalization of the deception interference guidance vector to quickly solve the dense suppression deception interference subspace, and then obtain the noise subspace and the projection matrix.

[0058] According to the present invention, for isolated suppression and strong deception combined interference, a space-frequency joint-multi-beam / zeroing-noise subspace projection method is used to achieve detection and suppression of combined interference;

[0059] For the combined interference of dense suppression and strong deception, the space-frequency joint-multi-beam / zeroing-noise subspace projection and the fast solution of the dense suppression interference subspace are deeply integrated to realize the detection and suppression of the combined interference.

[0060] The present invention will be described in more detail below by way of examples.

[0061] Embodiment 1:

[0062] like Figure 1As shown, this embodiment proposes a detection and suppression method for suppressing deception combined interference of high-precision anti-interference navigation. According to the characteristics of 6 kinds of combined interference, it organically integrates the space-frequency joint-multi-beam-noise subspace projection method, the interference subspace fast solution method, the true convex false deception interference detection, the deception interference recovery cancellation, the improved micro-pulse correlation (PAC) method, and the correlation peak detection and screening method, so as to effectively detect and suppress 6 kinds of combined interference;

[0063] In this embodiment, a combined interference detection and suppression method of the above methods is organically integrated, see Table 2;

[0064] Table 2 Detection and suppression methods for six combined interferences

[0065]

[0066] In this embodiment, the method specifically includes:

[0067] 1. Space-frequency joint-multi-beam / nulling-noise subspace projection method:

[0068] For the isolated suppression interference of combination interference 1 and 3 and combination interference 5, if the satellite position, array antenna phase center position, antenna array attitude, etc. are known, the space-frequency joint-multi-beam-noise subspace projection method is adopted; otherwise, the space-frequency joint-nulling-noise subspace projection method is adopted;

[0069] 1) The space-frequency joint-multi-beam-noise subspace projection method includes:

[0070] Step 1: After receiving, amplifying, down-converting, filtering, and analog-to-digital conversion by antenna array elements, RF channels, and analog-to-digital conversion units, the spatial signals are output as multiple digital intermediate frequency signals; each digital intermediate frequency signal is divided into two paths after serial / parallel conversion (S / P) and fast Fourier transform (FFT), one of which is sent to the first-in-first-out (FIFO) cache, and the other is sent to the weight vector calculation unit;

[0071] Step 2: The weight vector calculation unit uses multi-level Wiener filter forward decomposition and other feature decompositions to obtain the noise subspace and projection matrix;

[0072] Step 3: L desired satellite steering vectors are multiplied by the noise subspace projection matrix respectively, and then amplitude normalization is performed to obtain L optimal weight vectors for the array antenna beam to point to L satellites respectively;

[0073] Step 4: L optimal weight vectors are matched and weighted summed with the weighted data in the FIFO buffer to ensure that the null position and depth of the array antenna match the interference direction and strength, so as to achieve effective suppression of isolated interference and combined interference 5; at the same time, ensure that the synthetic beam points to the desired satellite to achieve high-quality reception of the desired satellite signal;

[0074] 2) The space-frequency joint-zeroing-noise subspace projection method includes:

[0075] The first step is the same as the first step of the above-mentioned space-frequency joint-multi-beam-noise subspace projection method;

[0076] Step 2: Same as the second step of the above space-frequency joint-multi-beam-noise subspace projection method;

[0077] Step 3: Use a vector whose only first element is non-zero Multiply it with the noise subspace projection matrix and then normalize the amplitude to obtain an optimal weight vector for the array antenna to zero-align the interference direction;

[0078] Step 4: The optimal weight vector is matched with the weighted data in the FIFO buffer and weighted summed to ensure that the null position and depth of the array antenna match the direction and intensity of the interference, so as to achieve effective suppression of isolated interference and combined interference 5;

[0079] 2. Space-frequency joint-multi-beam / nulling-noise subspace projection and intensive suppression interference subspace fast solution fusion:

[0080] For the dense suppression interference of combination interference 2 and 4 and combination interference 6, if the satellite position, array antenna phase center position, antenna array attitude, etc. are known, the space-frequency joint-multi-beam-noise subspace projection method is integrated with the dense suppression interference subspace fast solution method; otherwise, the space-frequency joint-zeroing-noise subspace projection method is integrated with the dense suppression interference subspace fast solution method;

[0081] The processing process of the space-frequency joint-multi-beam / nulling-noise subspace projection and dense suppression interference subspace fast solution fusion method is as follows;

[0082] The first step is the same as the first step of the above-mentioned space-frequency joint-multi-beam-noise subspace projection method;

[0083] Step 2: Use the fast solution method of dense suppressed interference subspace to obtain dense suppressed interference subspace, noise subspace and projection matrix; that is, expand the covariance matrix in the interference incident direction to obtain the expanded covariance matrix; use multi-level Wiener filtering based on the covariance matrix hierarchy to forward decompose the expanded covariance matrix, quickly solve the dense suppressed interference subspace, and then obtain the noise subspace and projection matrix;

[0084] Step 3: If the satellite position, array antenna phase center position, antenna array attitude, etc. are known, then the L expected satellite steering vectors are multiplied by the noise subspace projection matrix respectively, and then the amplitude is normalized to obtain the L optimal weight vectors for the array antenna beam to point to the L satellites respectively; otherwise, the vector Multiply it with the noise subspace projection matrix and then normalize the amplitude to obtain an optimal weight vector for the array antenna to zero-align the interference direction;

[0085] Step 4: L optimal weight vectors are matched and weightedly summed with the data to be weighted in the FIFO buffer to ensure that the position, depth, width of the array antenna null is matched with the interference direction, strength, and spatial distribution, so as to achieve effective suppression of dense suppression interference and combined interference 6; at the same time, ensure that the synthetic beam points to the desired satellite to achieve high-quality reception of the desired satellite signal; or, 1 optimal weight vector is matched and weightedly summed with the data to be weighted to ensure that the position, depth, width of the array antenna null is matched with the interference direction, strength, and spatial distribution, so as to achieve effective suppression of dense suppression interference and combined interference 6;

[0086] 3. Correlation peak detection and screening:

[0087] In the case of weak deception interference of combination interference 1 and 2, the correlation peak at the real pseudo code delay of the satellite signal is prominent and the main peak and the side lobe are easy to distinguish. There is a correlation peak at the deception pseudo code delay but it is not prominent. Therefore, the correlation peak detection and screening method is used to suppress it.

[0088] 1) Correlation peak detection includes:

[0089] The satellite signal adopts a direct sequence spread spectrum system, in which the spread spectrum sequence is a pseudo-random code sequence with sharp autocorrelation characteristics and flat cross-correlation characteristics; if there is weak deception interference, there will be more than one sharp correlation peak in the two-dimensional search space (pseudo-random code phase, Doppler frequency shift); if the number of correlation peaks detected is 1, it is judged that there is no deception interference; if the number of correlation peaks is greater than 1, it is judged that there is deception interference;

[0090] 2) Related peak screening includes:

[0091] After deceptive interference is detected (i.e. the number of correlation peaks is greater than 1), deceptive interference, especially forwarding interference, is usually delayed behind the satellite signal. Therefore, the correlation peaks with earlier pseudo code delay are selected and transferred to the tracking stage; the correlation peaks with later pseudo code delay are discarded and not transferred to the tracking stage.

[0092] 4. Suppress true and false deception interference detection, deception interference recovery and cancellation, improved PAC:

[0093] When the direction of the stronger deceptive interference in combination interference 3 and 4 is unknown, the true convex false deceptive interference detection, deceptive interference recovery cancellation and improved PAC method are adopted, including;

[0094] 1) Suppressing true convex false deception interference detection includes:

[0095] First, the visible satellite set is determined according to the almanac, the preliminary position, etc., and the satellite to be detected is selected from the visible satellite set; then, a virtual medium-intensity interference is applied to the signal direction of the satellite to be detected, and the virtual interference subspace and the noise subspace are obtained by quickly solving the virtual interference subspace, so that the array antenna forms a null in the direction of the satellite to be detected to suppress the signal of the satellite to be detected; finally, whether the deception interference exists is determined according to whether the navigation processing unit can capture and track the satellite to be detected or the non-visible satellite;

[0096] 2) Deception jamming recovery cancellation and improved PAC include:

[0097] First, based on the deceptive interference detection situation, the amplitude and phase of the deceptive interference are estimated to recover the deceptive interference; then it is subtracted from the received signal to suppress the deceptive interference to below -10dB; finally, the improved PAC method is used - a new correlator is added to search ~ The correlation peaks in the chip area are used to correct the phase detection function to suppress the residual deception interference. is a narrow correlator spacing;

[0098] 5. Space-frequency joint-multi-beam / nulling-noise subspace projection and isolated suppression deception interference subspace fast solution fusion:

[0099] For the known combined interference 3 with stronger deception interference, the space-frequency joint-multi-beam / nulling-noise subspace projection method is combined with the isolated suppression deception interference subspace fast solution method, and the processing process is as follows;

[0100] The first step is the same as the first step of the above-mentioned space-frequency joint-multi-beam-noise subspace projection method;

[0101] Step 2: Use the isolated suppression deception interference subspace fast solution method to obtain the isolated suppression deception interference subspace, noise subspace and projection matrix; that is, use the multi-level Wiener filter forward decomposition based on data hierarchy and the Schmidt orthogonalization of the deception interference guidance vector to quickly solve the isolated suppression deception interference subspace, and then obtain the noise subspace and projection matrix;

[0102] Step 3: If the satellite position, array antenna phase center position, antenna array attitude, etc. are known, then the L expected satellite steering vectors are multiplied by the noise subspace projection matrix respectively, and then the amplitude is normalized to obtain the L optimal weight vectors for the array antenna beam to point to the L satellites respectively; otherwise, the vector Multiply it with the noise subspace projection matrix and then normalize the amplitude to obtain an optimal weight vector for the array antenna to zero-align the interference direction;

[0103] Step 4: L optimal weight vectors are matched and weighted summed with the data to be weighted in the FIFO buffer to ensure that the null position and depth of the array antenna match the direction and strength of the interference, so as to achieve effective suppression of the combined interference 3; at the same time, ensure that the synthetic beam points to the desired satellite to achieve high-quality reception of the desired satellite signal; or, 1 optimal weight vector is matched and weighted summed with the data to be weighted to ensure that the null position and depth of the array antenna match the direction and strength of the interference, so as to achieve effective suppression of the combined interference 3;

[0104] 6. Space-frequency joint-multi-beam / nulling-noise subspace projection and intensive suppression deception interference subspace fast solution fusion:

[0105] For the known combined interference 4 with stronger deception interference, the space-frequency joint-multi-beam / nulling-noise subspace projection method is integrated with the dense suppression deception interference subspace fast solution method, and the processing process is as follows;

[0106] The first step is the same as the first step of the above-mentioned space-frequency joint-multi-beam-noise subspace projection method;

[0107] Step 2: Adopt the fast solution method of dense suppression deception interference subspace to obtain dense suppression deception interference subspace, noise subspace and projection matrix; that is, adopt the multi-level Wiener filter forward decomposition based on interference to expand the covariance matrix level and Schmidt orthogonalization of the deception interference guidance vector to quickly solve the dense suppression deception interference subspace, and then obtain the noise subspace and projection matrix;

[0108] Step 3: If the satellite position, array antenna phase center position, antenna array attitude, etc. are known, then the L expected satellite steering vectors are multiplied by the noise subspace projection matrix respectively, and then the amplitude is normalized to obtain the L optimal weight vectors for the array antenna beam to point to the L satellites respectively; otherwise, the vector Multiply it with the noise subspace projection matrix and then normalize the amplitude to obtain an optimal weight vector for the array antenna to zero-align the interference direction;

[0109] Step 4: L optimal weight vectors are matched and weightedly summed with the data to be weighted in the FIFO cache to ensure that the position, depth, width of the array antenna null sink matches the interference direction, strength, and spatial distribution, thereby effectively suppressing the combined interference 4; at the same time, ensure that the synthetic beam points to the desired satellite to achieve high-quality reception of the desired satellite signal; or, 1 optimal weight vector is matched and weightedly summed with the data to be weighted to ensure that the position, depth, width of the array antenna null sink matches the interference direction, strength, and spatial distribution, thereby effectively suppressing the combined interference 4.

[0110] The embodiments of the present invention propose a method for detecting and suppressing suppression deception combined interference for high-precision anti-interference navigation, which deeply integrates space-frequency joint-multi-beam / zeroing-noise subspace projection, correlation peak detection and screening, true convex suppression and false deception interference detection, deception interference recovery and cancellation, improved PAC, interference subspace fast solution and other methods; it systematically solves the detection and suppression problems of combined interference such as isolated suppression and weak deception, dense suppression and weak deception, isolated suppression and relatively strong deception, dense suppression and relatively strong deception, isolated suppression and strong deception, and dense suppression and strong deception.

[0111] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A method for detecting and suppressing combined interference of high-precision anti-interference navigation, characterized in that: include: For suppression and deception combined interference, one or at least two of the following methods are deeply integrated: space-frequency joint-multi-beam / zeroing-noise subspace projection, correlation peak detection and screening, true convex suppression and false deception interference detection, deception interference recovery cancellation, improved PAC, dense suppression / isolated suppression deception / dense suppression deception interference subspace fast solution method to achieve detection and suppression of combined interference.

2. The method according to claim 1, characterized in that The suppression and deception combination interference includes isolated suppression and weak deception combination interference, intensive suppression and weak deception combination interference, isolated suppression and relatively strong deception combination interference, intensive suppression and relatively strong deception combination interference, isolated suppression and strong deception combination interference and intensive suppression and strong deception combination interference; For the isolated suppression and weak deception combined interference, the space-frequency joint-multi-beam / zeroing-noise subspace projection, correlation peak detection and screening method are deeply integrated to achieve detection and suppression of combined interference, wherein the space-frequency joint-multi-beam / zeroing-noise subspace projection method is used to suppress isolated suppression interference, and the correlation peak detection and screening method is used to detect and suppress weak deception interference; The space-frequency joint-multi-beam-noise subspace projection method is used in the case where the satellite position, the phase center position of the array antenna, and the antenna array attitude are known, and includes the following steps: Step 1: The spatial signal is received, amplified, down-converted, filtered, and processed by the antenna array element, RF channel, and analog-to-digital conversion unit in sequence, and then multiple digital intermediate frequency signals are output; each digital intermediate frequency signal is then divided into two paths after serial / parallel conversion and fast Fourier transform, one path is sent to the FIFO buffer, and the other path is sent to the weight vector calculation unit; Step 2: The weight vector calculation unit uses multi-level Wiener filtering to perform forward decomposition to obtain the noise subspace and projection matrix; Step 3: multiply the L desired satellite steering vectors by the noise subspace projection matrix respectively, and normalize the multiplication results to obtain L optimal weight vectors for the array antenna beam to point to the L satellites respectively; Step 4: Match the L optimal weight vectors with the data to be weighted in the FIFO cache and perform weighted summation to ensure that the null position and depth of the array antenna match the direction and strength of the interference, and at the same time ensure that the synthetic beam points to the desired satellite to achieve high-quality reception of the desired satellite signal.

3. The method according to claim 2, characterized in that The space-frequency joint-zeroing-noise subspace projection method is used when the satellite position, the phase center position of the array antenna, and the antenna array attitude are unknown. The following steps are involved: The first step is the same as the first step of the space-frequency joint-multi-beam-noise subspace projection method; Step 2: The same as the second step of the space-frequency joint-multi-beam-noise subspace projection method; Step 3: multiply the noise subspace projection matrix by a vector whose only first element is non-zero, and normalize the multiplication result to obtain an optimal weight vector for aligning the array antenna null with the interference direction; Step 4: Match the optimal weight vector with the data to be weighted in the FIFO buffer, and perform weighted summation to ensure that the null position and depth of the array antenna match the direction and strength of the interference; The correlation peak detection and screening method comprises: 1) Mechanism and decision criteria of correlation peak detection: The satellite signal adopts a direct sequence spread spectrum system, in which the spread spectrum sequence is a pseudo-random code sequence with sharp autocorrelation characteristics and flat cross-correlation characteristics. If there is weak deception interference, there will be more than one sharp correlation peak in the two-dimensional search space of pseudo-random code phase and Doppler frequency shift; If the number of correlation peaks detected is 1, it is determined that there is no deceptive interference; If the number of correlation peaks is greater than 1, it is judged that there is deceptive interference; 2) Mechanism and processing method of relevant peak screening: After deceptive interference is detected, that is, the number of correlation peaks is greater than 1, the deceptive interference, especially the forwarding interference, usually lags behind the satellite signal; The correlation peaks with earlier pseudo code delay are selected and transferred to the tracking stage; the correlation peaks with later pseudo code delay are discarded and not transferred to the tracking stage.

4. The method according to claim 3, characterized in that For the combined interference of dense suppression and weak deception, the space-frequency joint-multi-beam / zeroing-noise subspace projection, the dense suppression interference subspace fast solution, and the correlation peak detection and screening method are deeply integrated to achieve the detection and suppression of combined interference, wherein the space-frequency joint-multi-beam / zeroing-noise subspace projection and the dense suppression interference subspace fast solution deep fusion method are used to suppress dense suppression interference, and the correlation peak detection and screening method is used to detect and suppress weak deception interference; The steps of the space-frequency joint-multi-beam / zeroing-noise subspace projection and densely suppressed interference subspace fast solution deep fusion method are the same as the first step, the third step and the fourth step of the space-frequency joint-multi-beam / zeroing-noise subspace projection method, and only the second step is different; the second step includes: using the densely suppressed interference subspace fast solution method to obtain the densely suppressed interference subspace, the noise subspace and the projection matrix, that is, first expanding the covariance matrix in the interference incident direction to obtain the expanded covariance matrix; then using a multi-level Wiener filter based on the covariance matrix hierarchy to forward decompose the expanded covariance matrix, quickly solve the densely suppressed interference subspace, and then obtain the noise subspace and the projection matrix.

5. The method according to claim 3, characterized in that: For the isolated suppression and strong deception combined interference, if the direction of the deception interference is unknown, the space-frequency joint-multi-beam / zeroing-noise subspace projection is deeply integrated with the true convex false deception interference detection, deception interference recovery cancellation, and improved PAC method to achieve detection and suppression of combined interference; if the direction of the deception interference is known, the space-frequency joint-multi-beam / zeroing-noise subspace projection and the isolated suppression deception interference subspace fast solution are deeply integrated to achieve detection and suppression of combined interference; The true suppression, false suppression, deception interference detection, deception interference recovery and cancellation, and improved PAC method include: 1) Suppressing true convexity and false deception interference detection: First, determine the visible satellite set according to the almanac and the approximate position, and select the satellite to be detected from the visible satellite set; Then, a virtual medium-intensity interference is created in the direction of the signal from the satellite to be detected, and a virtual interference subspace and a noise subspace are obtained by a fast solution method of a virtual interference subspace, that is, according to the upward steering vector of the satellite to be detected and the anti-interference freedom degree of the array antenna, so that the array antenna forms a null in the direction of the satellite to be detected to suppress the signal of the satellite to be detected; Finally, if the navigation processing unit can capture and track the satellite to be detected or the non-visible satellite, it is determined that there is deception interference; otherwise, it is determined that there is no deception interference; 2) Deception jamming recovery cancellation, improved PAC: Firstly, according to the deception interference detection situation, the amplitude and phase of the deception interference are estimated, and the deception interference is recovered; This is then subtracted from the received signal, suppressing the spoofing jammer to below -10dB; Finally, the improved PAC method is used, that is, a correlator search is added to the conventional PAC method. ~ Correlation peaks in the chip area are used to correct the phase detection function and suppress residual deception interference; The steps of the space-frequency joint-multi-beam / zeroing-noise subspace projection and isolated suppression deception interference subspace rapid solution deep fusion method are the same as the first, third and fourth steps of the space-frequency joint-multi-beam / zeroing-noise subspace projection method, with only the second step being different; the second step: adopting the isolated suppression deception interference subspace rapid solution method to obtain the isolated suppression deception interference subspace, the noise subspace and the projection matrix, that is, adopting the multi-level Wiener filtering forward decomposition based on data hierarchy and the Schmidt orthogonalization of the deception interference guidance vector to quickly solve the isolated suppression deception interference subspace, and then obtain the noise subspace and the projection matrix.

6. The method according to claim 3, characterized in that For the intensive suppression and strong deception combined interference, if the direction of the deception interference is unknown, the space-frequency joint-multi-beam / zeroing-noise subspace projection and the intensive suppression interference subspace are quickly solved, and deeply integrated with the true convex false deception interference detection, deception interference recovery cancellation, and improved PAC to achieve the detection and suppression of combined interference; if the direction of the deception interference is known, the space-frequency joint-multi-beam / zeroing-noise subspace projection and the intensive suppression deception interference subspace are quickly solved to achieve the detection and suppression of combined interference; The steps of the space-frequency joint-multi-beam / zeroing-noise subspace projection and intensive suppression deception interference subspace rapid solution deep fusion method are the same as the first step, the third step, and the fourth step of the space-frequency joint-multi-beam / zeroing-noise subspace projection method, and only the second step is different; The second step includes: using the densely suppressed deception interference subspace fast solution method to obtain the densely suppressed deception interference subspace, noise subspace and projection matrix, that is, using interference-based multi-level Wiener filtering forward decomposition of the expanded covariance matrix level and Schmidt orthogonalization of the deception interference guidance vector to quickly solve the densely suppressed deception interference subspace, and then obtain the noise subspace and projection matrix.

7. The method according to claim 3, characterized in that For the isolated suppression and strong deception combined interference, the space-frequency joint-multi-beam / zeroing-noise subspace projection method is used to achieve detection and suppression of the combined interference; For the dense suppression and strong deception combined interference, the space-frequency joint-multi-beam / zeroing-noise subspace projection and the dense suppression interference subspace fast solution are deeply integrated to realize the detection and suppression of the combined interference.

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