Satellite navigation deception jamming identification and positioning method based on passive synthetic aperture

Abstract

The application provides a satellite navigation deception jamming identification and positioning method based on passive synthetic aperture, comprising the following steps: mounting an antenna and a deception jamming signal receiver on a moving carrier and designing the moving carrier to move at a constant speed above a deception jamming source; designing the antenna to continuously receive deception jamming signals emitted by the deception jamming source below in a horizontal beam coverage time; processing the deception jamming signals by the receiver to obtain Doppler signals; performing matched filtering of the Doppler signals r'' under different matched filter frequency conditions by using a matched filter to obtain a frequency modulation-frequency modulation-time two-dimensional search matrix; obtaining the frequency modulation of the signal r'' based on the frequency modulation-frequency modulation-time two-dimensional search matrix; calculating the radial distance between the receiver and the deception jamming signal source under the zero Doppler plane based on the frequency modulation of r''; calculating the position information of the deception jamming source based on the radial distance; and judging the deception jamming signal according to the position information of the deception jamming source.

Description

Technical Field

[0001] This invention belongs to the field of radar and communication signal processing technology, and specifically relates to a method for identifying and locating satellite navigation deception interference based on passive synthetic aperture. Background Technology

[0002] In recent years, "navigation warfare" has gradually become a new form of warfare, and satellite navigation receivers have become one of the primary targets of enemy electromagnetic interference.

[0003] Electromagnetic interference targeting satellite navigation mainly falls into two categories: suppression jamming and deception jamming. The threat posed by suppression jamming is gradually decreasing. Compared to suppression jamming, deception jamming can achieve its jamming effect with lower power and is more covert.

[0004] Traditional methods for detecting deception interference based on array antennas have the following two main problems: (1) The number of deception interferences that can be detected is limited by the size and number of array elements; (2) The detection probability and measurement accuracy of deception interference signals with low signal-to-noise ratio are not high. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0006] Therefore, the present invention provides a method for identifying and locating satellite navigation deception interference based on passive synthetic aperture.

[0007] The technical solution of this invention is as follows: A method for identifying and locating satellite navigation spoofing interference based on passive synthetic aperture is provided, the method comprising:

[0008] Step 1: Mount the antenna and the deception jamming signal receiver on a moving platform and design the moving platform to move at a constant speed above the deception jamming source;

[0009] Step 2: Design an antenna to continuously receive deception interference signals emitted by the deception interference source below during the horizontal beam coverage time;

[0010] Step 3: Use a receiver to process the deception interference signal to obtain the Doppler signal r″, where the Doppler frequency of r″ exhibits linear frequency modulation characteristics;

[0011] Step 4: Using a matched filter, perform matched filtering with the Doppler signal r″ under different matched filter modulation frequencies to obtain the correlation values ​​of the filtering results corresponding to different matched filter modulation frequencies and different time delays, and generate a frequency modulation-azimuth time two-dimensional search matrix.

[0012] Step 5: Obtain the frequency modulation frequency of signal r″ based on the frequency modulation-azimuth-time two-dimensional search matrix, wherein the matched filter frequency corresponding to the largest correlation value in the matrix is ​​equal to the frequency modulation frequency of signal r″, and the time delay position of the largest correlation value is the azimuth time t below the zero Doppler plane. p ;

[0013] Step 6: Calculate the radial distance between the receiver and the spoofing interference signal source based on the frequency modulation of r″, the parameters of the spoofing interference source, and the flight speed of the moving vehicle;

[0014] Step 7: Calculate the location information of the deception interference source based on the radial distance between the receiver and the deception interference signal source under the zero Doppler plane, the geographical location of the receiver at the zero Doppler plane moment, the actual radial distance between the current receiver and the deception interference signal source, and the actual geographical location of the current receiver.

[0015] Step 8: Compare the location information of the deception interference source obtained in Step 7 with the real satellite position simulated by the deception interference signal to confirm whether the received signal is a deception interference signal.

[0016] Furthermore, the antenna is a wide-beam antenna with the antenna beam pointing vertically downwards; the moving vehicle is a drone or a low-orbit satellite.

[0017] Furthermore, step three includes:

[0018] 3.1 The interference signal received by the antenna is filtered, amplified, down-converted, and analog-to-digital converted to obtain a digital signal;

[0019] 3.2. Perform demodulation and decarrier processing on the digital signal to obtain the decarrier-free signal;

[0020] 3.3. The signal obtained in step 3.2 is segmented to obtain the segmented two-dimensional frequency modulated signal matrix r′(t);

[0021] 3.4 Perform square spectrum, normalization, and mean removal processing on each row of the two-dimensional frequency modulated signal matrix to obtain a two-dimensional frequency modulated signal square spectrum matrix;

[0022] 3.5 Extract the column signal corresponding to the zero frequency in the square spectrum matrix of the two-dimensional frequency-modulated signal. The column signal is the Doppler signal r″.

[0023] Furthermore, the carrier-decarrier signal is obtained using the following formula:

[0024]

[0025] Where ω1 is the residual frequency offset after carrier removal; ω0 is the carrier frequency of the deceiving interference source; c is the speed of light; θ is the initial phase; t p denoted as azimuth time at zero Doppler moment; j represents a complex number; t is time; v is the velocity of the moving vehicle; R0 is the radial distance between the deception jamming source and the receiver.

[0026] Furthermore, the segmented two-dimensional frequency-modulated signal matrix r′(t) is obtained through the following formula:

[0027]

[0028] Where Δt is the sampling interval; k is the frequency modulation frequency of the frequency modulation signal; Q×P represents Q rows × P columns.

[0029] Furthermore, the Doppler signal r″ is obtained by the following formula:

[0030]

[0031] Furthermore, in step four, the matched filter structure is designed using the following formula:

[0032]

[0033] Where μ is the modulation frequency of the matched filter, and T s The synthesis aperture time; i = 1, 2, 3, 4...

[0034] Furthermore, the step of performing matched filtering with the Doppler signal r″ under different matched filter modulation frequencies to obtain the correlation values ​​of the filtering results corresponding to different matched filter modulation frequencies and different time delays includes:

[0035] Determine the search step Δμ;

[0036] Determine the range of values ​​for the modulation frequency μ of the matched filter;

[0037] Multiple different matched filter modulation frequencies are determined based on the range of values ​​for the search step Δμ and the matched filter modulation frequency μ.

[0038] Different matched filter modulation frequencies are sequentially introduced into the matched filter structure to generate several sets of filters, and then matched and filtered with the received Doppler signal r″ to obtain the correlation values ​​of the filtering results corresponding to different matched filter modulation frequencies and different time delays.

[0039] Furthermore, the range of values ​​for the matched filter modulation frequency μ is: All are preset distance thresholds; the search step Δμ is Δμ = cμ 2 / ωv 2ΔR0 represents the positioning error.

[0040] Furthermore, the radial distance between the zero-Doppler receiver and the spoofing interference signal source is calculated using the following formula based on the modulation frequency of r″, the parameters of the spoofing interference source, and the flight speed of the moving vehicle:

[0041] 2k=ω0v 2 / cR0.

[0042] The above technical solution utilizes a moving carrier to carry an antenna in a regular motion. As the antenna flies over the deception interference source, it continuously receives signals emitted by the deception interference source within the horizontal beam coverage time. By demodulating and processing the deception interference signal to extract the carrier frequency signal, whose Doppler rate of change is approximately linear, this characteristic is used to perform long-term coherent accumulation of the received signal phase. Based on the correspondence between the zero Doppler plane and the Doppler modulation frequency of the received signal and the target position, combined with terrain data, the position coordinates of the deception interference source can be located. Then, by comparing it with the real satellite position simulated by the deception interference signal, it can be determined whether the signal source is a deception interference signal.

[0043] In other words, this technical solution utilizes a small-aperture, wide-azimuth antenna beam to coherently accumulate the carrier phase of the deception interference source over a long period of time, effectively synthesizing a large-aperture reconnaissance and positioning antenna, thereby forming a wide-area coverage, highly sensitive, and high-precision multi-deception interference source identification and positioning capability. This technical solution has broad application prospects. Attached Figure Description

[0044] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0045] Figure 1 A geometric model of a satellite navigation spoofing interference identification and localization method based on passive synthetic aperture provided in an embodiment of the present invention is shown. Detailed Implementation

[0046] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0048] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0049] like Figure 1 As shown, in one embodiment of the present invention, a method for identifying and locating satellite navigation spoofing interference based on passive synthetic aperture is provided, the method comprising:

[0050] Step 1: Mount the antenna and the deception jamming signal receiver on a moving platform and design the moving platform to move at a constant speed above the deception jamming source;

[0051] Step 2: Design an antenna to continuously receive deception interference signals emitted by the deception interference source below during the horizontal beam coverage time;

[0052] Step 3: Use a receiver to process the deception interference signal to obtain the Doppler signal r″, where the Doppler frequency of r″ exhibits linear frequency modulation characteristics;

[0053] Step 4: Using a matched filter, perform matched filtering with the Doppler signal r″ under different matched filter modulation frequencies to obtain the correlation values ​​of the filtering results corresponding to different matched filter modulation frequencies and different time delays, and generate a frequency modulation-azimuth time two-dimensional search matrix.

[0054] Step 5: Obtain the frequency modulation frequency of signal r″ based on the frequency modulation-azimuth-time two-dimensional search matrix, wherein the matched filter frequency corresponding to the largest correlation value in the matrix is ​​equal to the frequency modulation frequency of signal r″, and the time delay position of the largest correlation value is the azimuth time t below the zero Doppler plane. p ;

[0055] Step 6: Calculate the radial distance between the receiver and the spoofing interference signal source based on the frequency modulation of r″, the parameters of the spoofing interference source, and the flight speed of the moving vehicle;

[0056] Step 7: Calculate the location information of the deception interference source based on the radial distance between the receiver and the deception interference signal source under the zero Doppler plane, the geographical location of the receiver at the zero Doppler plane moment, the actual radial distance between the current receiver and the deception interference signal source, and the actual geographical location of the current receiver.

[0057] Step 8: Compare the location information of the deception interference source obtained in Step 7 with the real satellite position simulated by the deception interference signal to confirm whether the received signal is a deception interference signal.

[0058] In this embodiment of the invention, the real satellite position simulated by the deception interference signal is satellite position information derived from the real satellite ephemeris, which can be obtained through conventional technical means.

[0059] In this embodiment of the invention, the antenna is a wide-beam antenna (typically referring to a half-beam angle greater than 120 degrees), with the antenna beam pointing vertically downwards; the moving platform is a drone or a low-Earth orbit satellite. That is, this embodiment utilizes a drone, low-Earth orbit satellite, or other moving platform to carry a wide-beam antenna in uniform linear motion. The antenna beam is perpendicular to the platform and pointing downwards. As the antenna flies over a deception interference source, it continuously receives deception interference signals emitted by the source below the platform within the horizontal beam coverage time. This embodiment utilizes the virtual antenna aperture formed by the antenna's own motion to identify and locate satellite navigation deception interference signals.

[0060] like Figure 1As shown, assuming the slant distance between the spoofing interference source and the receiver is R, and the radial distance between the interference source and the receiver is R0, then the relationship between the two can be established as follows.

[0061]

[0062] The velocity of the receiver carrier is v, and the azimuth time at zero Doppler moment is t. p .

[0063] The model of the deception interference signal received by the receiver is:

[0064]

[0065] Where ω0 is the carrier frequency of the deception interference source, C(t) is the pseudo code chip of the deception signal, D(t) is the navigation message, c is the speed of light, and θ is the initial phase.

[0066] As can be seen, in this embodiment of the invention, an antenna mounted on a moving carrier moves in a regular pattern. As the antenna flies over the deception interference source, it continuously receives signals emitted by the deception interference source within the horizontal beam coverage time. By demodulating the deception interference signal to extract the carrier frequency signal, its Doppler rate of change is approximately linear. This characteristic is used to perform long-term coherent accumulation of the received signal phase. Based on the correspondence between the zero Doppler plane of the received signal and the Doppler modulation frequency and the target position, combined with terrain data, the position coordinates of the deception interference source can be located. Then, by comparing it with the real satellite position simulated by the deception interference signal, it can be determined whether the signal source is a deception interference signal.

[0067] In other words, the embodiments of the present invention utilize a small-aperture wide-azimuth antenna beam to coherently accumulate the carrier phase of the deception interference source over a long period of time, effectively synthesizing a large-aperture reconnaissance and positioning antenna, thereby forming a wide-area coverage, high-sensitivity, and high-precision multi-deception interference source identification and positioning capability. It can be used in various scenarios such as the daily spectrum supervision of the State Radio Regulatory Commission and the reconnaissance of spaceborne radiation sources, and has broad prospects for military and civilian applications.

[0068] In the above embodiments, in order to accurately obtain the Doppler signal r″, step three includes:

[0069] 3.1 The interference signal received by the antenna is filtered, amplified, down-converted, and analog-to-digital converted to obtain a digital signal;

[0070] 3.2. Perform demodulation and decarrier processing on the digital signal to obtain the decarrier-free signal;

[0071] 3.3. The signal obtained in step 3.2 is segmented to obtain the segmented two-dimensional frequency modulated signal matrix r′(t);

[0072] 3.4 Perform square spectrum, normalization, and mean removal processing on each row of the two-dimensional frequency modulated signal matrix to obtain a two-dimensional frequency modulated signal square spectrum matrix;

[0073] 3.5 Extract the column signal corresponding to the zero frequency in the square spectrum matrix of the two-dimensional frequency-modulated signal. The column signal is the Doppler signal r″.

[0074] In this embodiment of the invention, the acquisition and tracking loop of the receiver can be used to perform demodulation and decarrier processing on the digital signal.

[0075] In this embodiment of the invention, the carrier-decarrier signal is obtained by the following formula:

[0076]

[0077] Where ω1 is the residual frequency offset after carrier removal; ω0 is the carrier frequency of the deceiving interference source; c is the speed of light; θ is the initial phase; t p denoted as azimuth time at zero Doppler moment; j represents a complex number; t is time; v is the velocity of the moving vehicle; R0 is the radial distance between the deception jamming source and the receiver.

[0078] In this embodiment of the invention, the segmented two-dimensional frequency-modulated signal matrix r′(t) is obtained by the following formula:

[0079]

[0080] Where Δt is the sampling interval; k is the frequency modulation frequency of the frequency modulation signal; Q×P represents Q rows × P columns.

[0081] In this embodiment of the invention, the Doppler signal r″ is obtained by the following formula:

[0082]

[0083] Among them, the Doppler frequency of r″ exhibits a linear frequency modulation characteristic, with a modulation frequency of 2k = ω0v. 2 / cR0.

[0084] In the above embodiments, in step four, the matched filter structure can be designed using the following formula:

[0085]

[0086] Where μ is the modulation frequency of the matched filter, and T s The time for synthesizing the aperture is i; i = 1, 2, 3, 4..., that is, one i corresponds to a set of μ and t.

[0087] In the above embodiments, in order to accurately obtain the correlation values ​​of the filtering results corresponding to different matched filter modulation frequencies and different time delays, the process involves performing matched filtering with the Doppler signal r″ under different matched filter modulation frequencies to obtain the correlation values ​​of the filtering results corresponding to different matched filter modulation frequencies and different time delays, including...

[0088] 1) Determine the search step Δμ;

[0089] 2) Determine the range of values ​​for the modulation frequency μ of the matched filter;

[0090] 3) Determine multiple different matched filter modulation frequencies based on the range of values ​​for the search step Δμ and the matched filter modulation frequency μ;

[0091] 4) Different matched filter modulation frequencies are sequentially introduced into the matched filter structure to generate several sets of filters, and matched filtering is performed with the received Doppler signal r″ respectively to obtain the correlation values ​​of the filtering results corresponding to different matched filter modulation frequencies and different time delays.

[0092] The range of values ​​for the matched filter modulation frequency μ is as follows: All are preset distance thresholds, which can be set based on experience; the search step Δμ is Δμ = cμ 2 / ωv 2 ΔR0 represents the positioning error. When μ = ω0v 2 When / cR0, it can accurately match the Doppler signal. The modulation frequency of the matched filter corresponding to the maximum correlation value in the two-dimensional search matrix is ​​the modulation frequency ω0v of the Doppler signal. 2 / cR0, the time delay position where the maximum correlation value occurs is the positional time t below the zero Doppler plane. p Since the parameters of the jamming signal source and the flight speed of the receiver platform are known, the radial distance between the receiver and the jamming signal source can be obtained by solving for the tuning frequency.

[0093] In the above embodiments, the radial distance between the zero-Doppler receiver and the spoofing interference signal source is calculated using the following formula based on the modulation frequency of r″, the parameters of the spoofing interference source, and the flight speed of the moving vehicle:

[0094] 2k=ω0v 2 / cR0.

[0095] According to a specific embodiment of the present invention, the method of the present invention specifically includes the following steps:

[0096] Step 1: Use a drone, low-orbit satellite or other carrier to carry a wide-beam antenna and a deception jamming signal receiver, with the antenna beam pointing downwards, and control the drone to fly at a constant or near-constant speed in a straight line over an area with a deception jamming source, continuously receiving navigation deception jamming signals emitted by the deception jamming source below the carrier.

[0097] Assuming the slant distance between the spoofing interference source and the receiver is R, and the radial distance between the interference source and the receiver is R0, then the relationship between the two can be established as follows.

[0098]

[0099] The velocity of the receiver carrier is v, and the azimuth time at zero Doppler moment is t. p .

[0100] The model of the deception interference signal received by the receiver is:

[0101]

[0102] Where ω0 is the carrier frequency of the deception interference source, C(t) is the pseudo code chip of the deception signal, D(t) is the navigation message, c is the speed of light, and θ is the initial phase;

[0103] Step two: The receiver filters, amplifies, down-converts, and converts the interference signal received by the antenna to obtain a digital signal. The receiver's acquisition and tracking loop then demodulates and decarriers the digital signal to obtain the decarrier-free signal, as shown in the formula.

[0104]

[0105] Where ω1 is the residual frequency offset after carrier removal;

[0106] Step 3: Segment the signal obtained in Step 2 to obtain a segmented two-dimensional signal matrix.

[0107]

[0108] Where Δt is the sampling interval;

[0109] Step 4: Extract the square spectrum of each row of the two-dimensional frequency modulated signal matrix from Step 3 to obtain a two-dimensional frequency modulated signal square spectrum matrix;

[0110] Step 5: Extract the column signal corresponding to the zero frequency of the two-dimensional frequency modulation signal square spectrum matrix from Step 4. The column signal exhibits linear frequency modulation characteristics, and the modulation frequency of the linear frequency modulation signal is determined based on the linear frequency modulation characteristics.

[0111] Extract the column signal r″ corresponding to the zero frequency of the two-dimensional frequency-modulated signal square spectrum matrix from step four, as shown in the following formula. The Doppler frequency of r″ exhibits linear frequency modulation characteristics, and the modulation frequency is...

[0112]

[0113] Step 6: Generate a matched filter locally. The matched filter is matched and filtered with the received Doppler signal. The matched filtering results at different modulation frequencies are collected. The correlation values ​​corresponding to different modulation frequencies and different time delays are recorded. A two-dimensional search matrix of modulation frequency-azimuth time is generated.

[0114] The structure of the matched filter is shown in the following formula. The matched filter performs matched filtering with the received Doppler signal r″, collects the matched filtering results under different modulation frequencies, records the correlation values ​​corresponding to different modulation frequencies μ and different time delays t, and generates a two-dimensional search matrix of modulation frequency-azimuth time.

[0115]

[0116] Where μ is the modulation frequency of the matched filter, and T s The time for synthesizing the pore size is given, where μ ranges from 1 to 1. in The search step Δμ = cμ is determined based on the positioning error ΔR0. 2 / ωv 2 ΔR0, when μ=ω0v 2 When / cR0, it can accurately match the Doppler signal;

[0117] The estimated value of μ is successively substituted into the matched filter to generate several sets of filters, and matched filtering is performed with the received Doppler signal r″. The results of the matched filter under different modulation frequencies μ are collected, and the correlation values ​​corresponding to different modulation frequencies μ and different time delays t are recorded to generate a two-dimensional search matrix M of modulation frequency-azimuth time.

[0118] Step 7: The modulation frequency of the Doppler signal, ω0v, is the matched filter frequency corresponding to the maximum correlation value in the two-dimensional search matrix obtained in Step 6. 2 / cR0, the time delay position where the maximum correlation value occurs is the positional time t below the zero Doppler plane. p Since the parameters of the jamming signal source and the flight speed of the receiver platform are known, the radial distance R0 between the receiver and the jamming signal source can be obtained by solving for the modulation frequency.

[0119] Step 8: Using the true distance R0 between the receiver and the spoofing jamming signal at the zero Doppler plane obtained in Step 7, and the geographical location information of the receiver at the zero Doppler plane time, the location information of the spoofing jamming information source is derived by combining the true distance R0 and the geographical location information, and compared with the real satellite position simulated by the spoofing jamming signal to confirm whether the received signal is a spoofing jamming signal.

[0120] As can be seen, the satellite navigation spoofing interference identification and localization method based on passive synthetic aperture proposed in this invention utilizes the uniform relative motion characteristics between the monitoring platform and the spoofing interference source. It employs a small-aperture, wide-azimuth antenna beam to coherently accumulate the carrier phase of the spoofing interference source over a long period, effectively synthesizing a large-aperture reconnaissance and localization antenna. This results in a wide-area coverage, high-sensitivity, and high-precision multi-spoofing interference source identification and localization capability. The method of this invention can be used in various scenarios such as routine spectrum monitoring by the State Radio Regulatory Commission and reconnaissance of spaceborne radiation sources, showing broad prospects for both military and civilian applications.

[0121] The features described and / or illustrated above with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, and / or in combination with or in lieu of features in other embodiments.

[0122] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, whole, step, or component, but does not exclude the presence or addition of one or more other features, wholes, steps, components, or combinations thereof.

[0123] The methods described above in this invention can be implemented in hardware or in combination with software. This invention relates to computer-readable programs that, when executed by a logic component, enable the logic component to implement the aforementioned apparatus or constituent parts, or to implement the various methods or steps described above. This invention also relates to storage media for storing the above programs, such as hard disks, magnetic disks, optical disks, DVDs, flash memory, etc.

[0124] Many features and advantages of these embodiments are apparent from this detailed description, and therefore the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Furthermore, since many modifications and alterations will readily occur to those skilled in the art, the embodiments of the invention are not intended to be limited to the precise structures and operations illustrated and described, but rather to encompass all suitable modifications and equivalents falling within their scope.

[0125] The parts of this invention not described in detail are techniques known to those skilled in the art.

Claims

1. A method for identifying and locating satellite navigation spoofing interference based on passive synthetic aperture, characterized in that, The method includes: Step 1: Mount the antenna and the deception jamming signal receiver on a moving platform and design the moving platform to move at a constant speed above the deception jamming source; Step 2: Design an antenna to continuously receive deception interference signals emitted by the deception interference source below during the horizontal beam coverage time; Step 3: Process the deception interference signal using a receiver to obtain the Doppler signal. ,in, The Doppler frequency exhibits linear frequency modulation characteristics; Step 4: Using a matched filter with the Doppler signal under different matched filter modulation conditions. Perform matched filtering to obtain the correlation values ​​of the filtering results corresponding to different matched filter modulation frequencies and different time delays, and generate a frequency modulation-azimuth time two-dimensional search matrix; Step 5: Obtain the signal based on the frequency modulation-azimuth time two-dimensional search matrix. The modulation frequency of the matched filter is given by the matrix, where the maximum correlation value in the matrix corresponds to a modulation frequency equal to the signal frequency. The modulation frequency, the time delay position where the maximum correlation value occurs is below the zero Doppler plane in the positional time. ; Step Six: Based on the above The radial distance between the receiver and the spoofing interference source is calculated by determining the frequency modulation, parameters of the spoofing interference source, and the flight speed of the moving vehicle, under the zero Doppler plane. Step 7: Calculate the location information of the deception interference source based on the radial distance between the receiver and the deception interference signal source under the zero Doppler plane, the geographical location of the receiver at the zero Doppler plane moment, the actual radial distance between the current receiver and the deception interference signal source, and the actual geographical location of the current receiver. Step 8: Compare the location information of the deception interference source obtained in Step 7 with the real satellite position simulated by the deception interference signal to confirm whether the received signal is a deception interference signal. Step three includes: 3.1 Filtering, amplifying, down-converting, and analog-to-digital converting the interference signal received by the antenna to obtain a digital signal; 3.

2. Perform demodulation and decarrier processing on the digital signal to obtain the decarrier-free signal; 3.

3. The signal obtained in step 3.2 is segmented to obtain a segmented two-dimensional frequency-modulated signal matrix. ; 3.4 Perform square spectrum, normalization, and mean removal processing on each row of the two-dimensional frequency modulated signal matrix to obtain a two-dimensional frequency modulated signal square spectrum matrix; 3.5 Extract the column signal corresponding to the zero frequency in the squared spectrum matrix of the two-dimensional frequency-modulated signal. The column signal is the Doppler signal. .

2. The method according to claim 1, characterized in that, The antenna is a wide-beam antenna with the antenna beam pointing vertically downwards; the moving vehicle is a drone or a low-orbit satellite.

3. The method according to claim 1, characterized in that, The carrier-decarrier signal is obtained using the following formula: in, The residual frequency offset after carrier removal; To deceive the carrier frequency of the interference source, where c is the speed of light, Initial phase; The azimuth time at zero Doppler moment; Represents a complex number; For time; For the speed of the moving vehicle; To deceive the radial distance between the interference source and the receiver.

4. The method according to claim 3, characterized in that, The segmented two-dimensional frequency-modulated signal matrix is ​​obtained using the following formula. : ,in, The sampling interval; To adjust the frequency of an FM signal; represent .

5. The method according to claim 4, characterized in that, The Doppler signal We obtain it from the following formula: .

6. The method according to any one of claims 1-5, characterized in that, In step four, the matched filter structure is designed using the following formula: ,in, To tune the frequency of the matched filter, The time for synthesizing the aperture; .

7. The method according to claim 6, characterized in that, The method utilizes matched filters under different matched filter frequency modulation conditions with the Doppler signal. Perform matched filtering to obtain the correlation values ​​of the filtering results corresponding to different matched filter modulation frequencies and different time delays, including: Determine the search step ; Determine the tuning frequency of the matched filter The range of values ​​for ; According to the search steps Matched filter frequency modulation The range of values ​​determines multiple different matched filter modulation frequencies; different matched filter modulation frequencies are sequentially substituted into the matched filter structure to generate several sets of filters, which are then compared with the received Doppler signal. Perform matched filtering to obtain the correlation values ​​of the filtering results corresponding to different matched filter modulation frequencies and different time delays.

8. The method according to claim 7, characterized in that, Matched filter frequency modulation The range of values ​​is , , All are preset distance thresholds; the search step for , This represents the positioning error.

9. The method according to claim 8, characterized in that, Based on the following formula The radial distance between the receiver and the spoofing interference source is calculated by determining the frequency modulation, parameters of the spoofing interference source, and the flight speed of the moving vehicle, under the zero-Doppler plane: .

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