Satellite Navigation Spoofing Interference Detection Method Based on Array Antenna and INS Fusion Processing

Abstract

The present invention discloses a satellite navigation spoofing interference detection method based on the fusion processing of an array antenna and INS. The method first activates the spatial detection mode of the array antenna to determine whether there is strong spoofing interference in space and adaptively nullify and suppress the strong spoofing interference. Then, using the beamforming of the array antenna and cooperating with the attitude information of INS, a beam pointing is formed for the space satellites to determine whether there is medium spoofing interference in space. Subsequently, the array antenna resumes the working mode of the beam pointing and starts the low-intensity spoofing interference detection process in the next stage. Finally, it enters the information processing stage for spoofing interference detection. The present invention realizes the full-dimensional detection of spoofing interference in the spatial domain, signal domain, and information domain by adopting the fusion processing of an array antenna and INS, has a wide range of applications, is not restricted by spoofing patterns and intensities, and has a high success rate of spoofing detection.

Description

Technical Field

[0001] The present invention relates to the field of satellite navigation applications, and particularly relates to a satellite navigation spoofing interference detection method based on the fusion processing of an array antenna and an INS. Background Art

[0002] With the development of global satellite navigation systems, satellite navigation and positioning devices have become the main means for finding spatial positions, speed measurement, and path navigation, and have profoundly affected human daily life and national security. Satellite navigation and positioning devices are widely used in various fields such as communication, radar, civil aviation, and transportation, and provide services such as positioning, speed measurement, navigation, and timekeeping. With the in-depth application of satellite navigation, higher requirements are put forward for the availability, continuity, integrity, etc. of satellite navigation. The anti-jamming satellite navigation application based on an array antenna and the integrated navigation of an INS (Inertial Navigation System) have gradually become the mainstream configuration of satellite navigation and positioning devices, and more and more attention is paid to the safety and reliability of satellite navigation applications. However, since the satellite navigation signals reaching the ground are relatively weak, and the working frequency points, signal systems, message formats, etc. of the navigation signals are all public, in satellite navigation, generative simulation interference and retransmission spoofing have become important means, and a strong demand for the detection of spoofing interference in satellite navigation has emerged accordingly.

[0003] Spoofing interference mainly takes advantage of the weak links in the working characteristics and signal systems of satellite navigation and positioning devices, and has gradually become the natural enemy of satellite navigation and positioning devices due to its good concealment and high interference efficiency. Any spoofing interference includes two links: generation and transmission. Therefore, spoofing interference is divided into generative spoofing and retransmission spoofing according to the generation method, and is also divided into single-antenna spoofing and multi-antenna spoofing according to the spoofing interference transmission method. The spoofing patterns after combining the two links are even more complex and diverse. With the development of satellite navigation spoofing interference means, spoofing interference has also evolved from traditional weak-signal deception to suppression-type strong-interference deception based on spoofing signals, medium-strength deception matching the space signal, weak-signal deception with multi-satellite distribution, etc. In practical applications, the spoofing interference patterns are even more complex and changeable.

[0004] Many scholars have given corresponding spoofing interference detection methods according to different spoofing interference signals and different application environments, such as spoofing interference detection methods like power detection, Doppler detection, and autonomous integrity detection. The above methods are all effective for weak-signal spoofing interference patterns. When facing complex and diverse spoofing interferences of various intensities and patterns such as high, medium, and low, there are great limitations:

[0005] 1. With the development of jamming methods, spoofing jamming has evolved from traditional weak-signal spoofing to multi-dimensional spoofing jamming such as high-intensity suppression, medium-intensity blocking, and low-intensity deception; traditional spoofing jamming detection algorithms are only effective for low-intensity weak-signal spoofing jamming.

[0006] 2. A spoofing jamming detection method based on signal power, which detects the presence of spoofing signals through the power intensity and changes of spoofing signals. However, due to factors such as antenna type, antenna attitude, and multipath effects, there is a high probability of false alarm detection.

[0007] 3. A spoofing jamming detection method based on signal Doppler, which uses the difference in the dynamics of the satellite navigation receiver relative to the satellite and the carrier of the spoofing jamming for spoofing jamming detection. When the dynamics of the satellite receiver are small, or for spoofing with a multi-antenna transmission method, this method has significant application limitations.

[0008] 4. A spoofing jamming detection method based on receiver autonomous integrity, which uses the estimation of residuals in positioning solution to identify spoofing jamming. This method is only effective when there is spoofing for 1 or 2 satellites. When there is generative spoofing for multiple satellites, this method is powerless.

[0009] With the development of satellite navigation applications, the combination of anti-jamming array antennas and INS has become the standard configuration of satellite navigation positioning devices. For the widely used anti-jamming array antenna and INS architecture, how to achieve real-time detection of multi-intensity and multi-style satellite navigation spoofing signals based on the device's own characteristics without adding external auxiliary means has become the key to the application of satellite navigation positioning devices.

[0010] The present invention is particularly applicable to the problem that the satellite navigation positioning device based on array antennas and INS cannot be normally positioned or the positioning deviates due to the influence of spoofing jamming when working in a complex spoofing jamming environment, solves the problems and difficulties of the limited application of satellite navigation positioning devices in complex spoofing jamming scenarios, and improves the anti-spoofing performance of satellite navigation positioning devices and their integrity and robustness in complex electromagnetic environments. Summary of the Invention

[0011] The object of the present invention is to avoid the deficiencies in the above-mentioned background art. By utilizing the device characteristics of existing array antennas and cooperating with inertial navigation INS assistance, a method for detecting multi-intensity and multi-style spoofing interference in satellite navigation based on the fusion processing of array antennas and INS is proposed. This method conducts spoofing interference detection throughout the entire working process of the satellite navigation positioning device, expands the spoofing interference detection from the original traditional signal domain detection to full-dimensional domain detection such as spatial domain detection, signal domain detection, and information domain detection, and realizes seamless coverage of the full-dimensional domain of spoofing interference detection through a multi-means fusion processing method.

[0012] The present invention first activates the spatial domain detection method of the array antenna, uses active nulling and adaptive nulling processing to identify the interference power of the receiver's spatial signal, and at the same time cooperates with the beam pointing to identify the spoofing signal in the receiver's space. If there is a satellite navigation signal with a power exceeding the noise signal power, it is determined that there is strong spoofing interference in the space, the spoofing signal is marked, and the strong spoofing interference is suppressed by adaptive nulling. If no strong spoofing interference is identified, it is determined that there is no strong spoofing interference in the space. Then continue to transfer to the next stage of the spoofing interference detection process.

[0013] Utilize the beamforming of the array antenna and cooperate with the attitude information of INS to form a beam pointing to the space satellites, and improve the receiving gain of the space satellite signals. Activate the signal acquisition processing of the navigation positioning device, conduct multi-correlation peak detection and signal power detection on the satellite numbers within the beam pointing. If there are multiple correlation peaks for the same satellite within the same beam, and the signal power intensity of some of the correlation peaks exceeds the threshold of the normal space signal, it is determined that there is medium spoofing interference in the space, and the spoofing signal is marked and displayed; if there are correlation peaks for multiple satellites within the same beam, and the signal power intensity of the satellites all exceeds the maximum threshold of the normal space signal, activate the active nulling of the spatial domain detection for identification. If all the correlation peaks of the satellites disappear or the signal power decreases by more than 30 dB after the active nulling is activated, it is determined that there is medium spoofing interference in the space, and the spoofing signal is marked and displayed; otherwise, there is no medium spoofing interference in the space, and continue to transfer to the next stage of the spoofing interference detection process.

[0014] The working mode of the array antenna to restore the beam pointing is enabled, and the low-intensity spoofing interference detection process of the next stage is started. First, the spatial beam points to the satellite for signal acquisition. Through the detection of multiple correlation peaks in the signal acquisition, the spoofing interference is identified. If there are multiple correlation peaks for a single satellite, it is determined that there is low-intensity spoofing interference in the space, and the spoofing signal is marked and displayed. Then the device enters the signal tracking stage, performs tracking processing on the satellites received in space, and discriminates the signal power of the satellites. If the signal power exceeds the threshold of the real satellite, it is determined that there is low-intensity spoofing signal in the space, and the spoofing signal is marked and displayed. At the same time, data monitoring such as the pseudorange consistency between beams, the pseudorange consistency between frequency points, and the pseudorange change consistency based on INS assistance is performed on the observables output by satellite tracking. If the detection results of the pseudorange consistency between beams, the pseudorange consistency between frequency points, and the pseudorange change consistency based on INS assistance for the same satellite number are inconsistent, it is determined that there is low-intensity spoofing signal in the space, and the spoofing signal is marked and displayed.

[0015] After completing the spoofing interference detection of signal tracking, it enters the information processing stage for spoofing interference detection. The autonomous integrity residual detection and clock error jitter anomaly detection of the device are performed using the observables output by signal tracking. If the detection results exceed the preset threshold, it is determined that there is a spoofing signal in the space, and the spoofing signal is marked and displayed. Finally, the identification and alarm output of all spoofing signals are completed.

[0016] This method realizes the full-dimensional detection of spoofing interference in the spatial domain, signal domain, and information domain by using the fusion processing method of the array antenna and INS. It has a wide range of applications and is not restricted by spoofing patterns and intensities. Whether the spoofing signal is strong spoofing interference, medium spoofing interference, low-intensity spoofing interference and other multiple intensity levels of spoofing interference, or single-antenna spoofing, multi-antenna spoofing, etc. and various combinations of spoofing patterns, this method is effective and has a high spoofing detection success rate.

[0017] The present invention proposes a satellite navigation spoofing interference detection method based on the fusion processing of an array antenna and INS. This method includes the following steps:

[0018] S1) The active nulling and adaptive nulling unit for spatial domain detection based on the array antenna identifies the power of strong spoofing interference in the space, and at the same time cooperates with the beam pointing to identify the strong spoofing interference in the space. If there is a satellite navigation signal whose signal power exceeds the noise spectrum, it is determined that there is strong spoofing interference in the space, the status of the corresponding satellite navigation signal is marked, and the adaptive nulling function is started to adaptively null and suppress the strong spoofing interference. If no strong spoofing interference is detected, it is determined that there is no strong spoofing interference in the space, and the spoofing interference detection process of the next stage is continued.

[0019] S2) Generate beam weights using the attitude assistance information of INS and satellite ephemeris information. The array antenna synthesizes beams to form beam pointing towards the space-receiving satellite, enhancing the signal reception gain of the space-receiving satellite and suppressing signals in the airspace outside the satellite direction. Start the signal acquisition and processing of the device, perform multi-correlation peak detection and signal power detection on the satellites within the beam pointing. If there are multiple correlation peaks for the same satellite within the same beam and the signal power intensity of some of the correlation peaks exceeds the threshold of the normal space signal, it is determined that there is medium spoofing interference in the signal reception space, and the relevant signals are marked and displayed; continue to perform signal acquisition for the satellites within the beam pointing. If there are correlation peaks of multiple satellites within the same beam and the signal power intensity of the satellites all exceeds the maximum threshold of the normal space satellite signal, start the active nulling of the airspace detection for identification and form active nulling suppression in the original beam pointing. If after the active nulling is started, the correlation peaks of all satellites disappear or the signal power decreases by more than 30 dB, it is determined that there is medium spoofing interference in the space, and the spoofing signals are marked and displayed; otherwise, there is no medium spoofing interference in the space, and continue to transfer to the next stage of the spoofing interference detection process.

[0020] S3) The array antenna resumes the beam pointing working mode and starts the low-intensity spoofing interference detection process of the next stage. First, perform signal acquisition on multiple beam-pointing satellites. Through the multi-correlation peak detection in signal acquisition, identify spoofing interference. If there are multiple correlation peaks for a single satellite, it is determined that there is low-intensity spoofing interference in the signal reception space, and the relevant signals are marked and displayed; then the device transfers to the signal tracking stage, performs tracking processing on the space-receiving satellites, and discriminates the signal power of the satellites. If the signal power of the satellite exceeds the threshold of the real satellite, it is determined that the satellite signal is low-intensity spoofing interference, and the spoofing signals are marked and displayed; finally, monitor data such as the consistency of pseudorange between beams, the consistency of pseudorange between frequency points, and the consistency of pseudorange change amount based on INS assistance for the observables output by satellite tracking to detect low-intensity spoofing interference that may be missed; if the detection results of the consistency of pseudorange between beams, the consistency of pseudorange between frequency points, and the consistency of pseudorange change amount based on INS assistance for the same satellite are inconsistent, it is determined that the satellite is low-intensity spoofing interference, and the spoofing signals are marked and displayed; otherwise, there is no low-intensity spoofing interference and missed-alarm spoofing interference in the space, and continue to transfer to the next stage of the spoofing interference detection process.

[0021] S4) Finally, using the results of signal domain spoofing detection in the previous stage (steps S1)-S3)), possible undetected spoofing jamming is detected through information domain spoofing jamming detection. The pseudorange observables output by space satellite signal tracking are used for multi-satellite autonomous integrity residual detection and satellite clock error jitter anomaly detection and verification. If the autonomous integrity residual detection result of a certain satellite exceeds the threshold or the satellite clock error jitter exceeds the threshold, the satellite signal is determined to be a spoofing signal, and the spoofing signal is marked and displayed; otherwise, there is no spoofing jamming (spoofing signal) in space. Through the spoofing jamming detection in the information domain, the possible undetected spoofing jamming in the above steps is supplemented and verified again, and finally the identification, detection, recording and alarm output of all spoofing signals are completed.

[0022] Through the above steps, multi-level and full-dimensional real-time online detection of all types of satellite navigation spoofing jamming is completed.

[0023] Among them, in step S1), based on the architecture of the existing array antenna navigation and positioning device, the array antenna hardware platform of the traditional device is not changed, and the device working process is not changed. Based on the existing active nulling and adaptive nulling processing design in the adaptive filtering unit of the array antenna, combined with the beam pointing function, strong spoofing jamming existing in space is detected and suppressed. The strong spoofing jamming is detected by identifying the power of the spoofing jamming. If there is high-intensity suppression spoofing jamming, it is directly marked and the strong spoofing jamming is suppressed by forming an active null. If not, the spoofing detection process of step S2) is entered.

[0024] Among them, in step S2), the signal after suppressing strong spoofing jamming in step S1) is used for medium spoofing jamming identification. Based on the INS attitude assistance information and the space satellite ephemeris information, a beam pointing is formed for the space-received satellites, and then the signal acquisition process is started. Multi-correlation peak detection and signal power detection are performed on the satellites within the beam pointing. If there are multiple correlation peaks for the same satellite within the same beam, and the signal power intensity of some of the correlation peaks exceeds the threshold of the normal space signal, it is determined that there is medium spoofing jamming in the signal reception space, and the spoofing signal is marked and displayed; if there are correlation peaks for multiple satellites within the same beam, and the signal power intensity of the satellites all exceeds the maximum threshold of the normal space satellite signal, the active nulling of the airspace detection is started for identification, and an active nulling suppression is formed in the original beam pointing. If all the correlation peaks of the satellites disappear or the signal power decreases by more than 30 dB after the active nulling is started, it is also determined that there is medium spoofing jamming in space, and the spoofing signal is marked and displayed; otherwise, there is no medium spoofing jamming in space, and the spoofing jamming detection process of step S3) is continued.

[0025] Among them, in step S3), on the basis of completing step S2), the array antenna resumes the beam pointing working mode, forms a beam pointing for the space-received satellite, and starts the low-intensity spoofing interference detection process based on the signal domain. The multi-correlation peak detection of the satellite is completed by capturing the signal of the satellite pointed by the beam, and the spoofing interference is identified. If there are multiple correlation peaks for a single satellite, it is determined that there is low-intensity spoofing interference in the signal reception space, and the spoofing signal is marked and displayed; then the device enters the signal tracking stage, performs tracking processing on the space-received satellite, and discriminates the signal power of the satellite. If the signal power of the satellite exceeds the threshold of the real satellite, it is determined that the signal of the satellite is low-intensity spoofing interference, and the spoofing signal is marked and displayed; finally, data monitoring methods such as inter-beam pseudorange consistency, inter-frequency pseudorange consistency, and INS-assisted pseudorange change consistency of the observables output by satellite tracking are used to detect possible missed-alarm low-intensity spoofing interference; if the inter-beam pseudorange consistency, inter-frequency pseudorange consistency, and INS-assisted pseudorange change consistency detection results of the same satellite are inconsistent, it is determined that the satellite is low-intensity spoofing interference, and the spoofing signal is marked and displayed; otherwise, there is no low-intensity spoofing interference in the space, and the process continues to step S4) for the spoofing interference detection process.

[0026] Finally, in step S4), on the basis of completing step S3), the achievements of signal domain spoofing detection in step S3) are utilized to detect possible missed-alarm spoofing interference through information domain detection. The multi-satellite autonomous integrity residual detection and satellite clock error jitter anomaly detection and verification are carried out using the pseudorange observables output by space satellite signal tracking. If the combined autonomous integrity residual detection result of a certain satellite and other satellites exceeds the threshold or the satellite clock error jitter exceeds the threshold, it is determined that the signal of the satellite is a spoofing signal, and the spoofing signal is marked and displayed; otherwise, there is no spoofing interference in the space. Using the spoofing interference detection in the information domain, the possible missed-alarm spoofing interference in the above steps is re-supplemented and verified, and finally the identification, detection, recording, and alarm output of all spoofing signals are completed. Through the full-dimensional domain processing of the fusion of the array antenna and INS, the online real-time multi-level and full-dimensional seamless and efficient detection of various complex spoofing interference scenarios of the navigation and positioning device is completed.

[0027] The present invention adopts array antenna, INS, and full-dimensional fusion processing to suppress strong deception interference, medium deception interference blocking, low-intensity deception interference deception and other multi-intensity deceptions; it can achieve full-dimensional seamless coverage of deception interference detection for multiple deceptions such as generative deception, forwarding deception, single antenna deception, multi-antenna deception, and combined deception; the deception interference detection of the present invention integrates multiple dimensional fusion processing methods such as airspace detection, signal domain detection, and information domain detection with the help of array antenna and inertial navigation INS, and realizes multi-dimensional domain stereo detection of deception interference signals. Compared with the single detection methods based on signal power, Doppler, and receiver autonomous integrity in the background technology, the detection method is reliable and accurate; based on the existing array antenna and INS hardware architecture of satellite navigation and positioning equipment, the present invention does not need to build additional conditions and environmental support for deception interference detection, does not need to change the existing hardware architecture of the positioning equipment, and does not need external auxiliary information. It only adds an independent deception interference detection algorithm and processing flow to the signal processing algorithm, and the engineering implementation is simple and the updateability is strong; the deception signal detection of the present invention adopts the signal processing full-dimensional fusion processing and multi-means redundant verification. The detection false alarm rate of deceptive interference is low, which comprehensively improves the integrity and robustness of the positioning equipment and is suitable for high-security application fields such as civil aviation. The present invention does not rely on the signal format and has a wide range of applications. It is suitable for all satellite navigation systems, data link measurement systems, communication measurement and control systems, etc. It is not restricted by signal systems such as public signals and authorized signals, and has good promotion and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a working principle diagram of satellite navigation deception interference detection based on array antenna and INS fusion processing;

[0029] Figure 2 This is the workflow diagram of satellite navigation deception interference detection based on array antenna and INS fusion processing. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0031] Reference Figure 1 and Figure 2, in view of the drawbacks of the current single method for detecting spoofing interference in satellite navigation and positioning devices, such as large limitations in applicable scenarios, high false alarm and missed alarm rates, a method for detecting satellite navigation spoofing interference based on the fusion processing of an array antenna and INS is proposed. Based on the traditional design architecture of the array antenna and INS in the satellite navigation and positioning device, without the need to add additional equipment accessories and supporting conditions, the detection process of spoofing interference runs through the entire working process of the navigation and positioning device. The spoofing interference detection is divided into spatial domain detection, signal domain detection, and information domain detection, and a multi-means fusion processing method is used to achieve seamless coverage in multiple levels and full-dimensional domains for spoofing interference detection. First, based on the active nulling and adaptive nulling processing unit of the array antenna, power identification of strong spoofing interference in space is performed, and then the strong spoofing interference is suppressed through adaptive nulling. Then, using the beamforming of the array antenna and the attitude information of INS, beam pointing formation and active nulling suppression in the spatial domain are carried out, and at the same time, multi-peak detection and power detection in the signal domain are coordinated to identify and suppress medium spoofing interference. The multi-correlation peaks and power threshold values of the spoofing signal are used to identify medium spoofing interference through the joint of the spatial domain and the signal domain. At the same time, consistency detection of pseudorange between beams, dual-frequency pseudorange consistency detection, and INS-assisted pseudorange rate of change consistency detection are performed on the pseudorange output by signal tracking to identify low-intensity spoofing signals through consistency detection. Finally, multi-satellite autonomous integrity residual detection and multi-satellite clock difference abnormal residual detection in the information domain are used to complete the screening and filtering of missed alarms of spoofing interference and complete the detection of complex spoofing interference scenarios in space. The above method is used to complete the seamless full-coverage detection of spoofing interference with multiple intensities, multiple styles, multiple levels, and multiple dimensions, and the spoofing signal recognition result is output in real time as spoofing signal alarm information.

[0032] The working principle diagram of satellite navigation spoofing interference detection based on the fusion processing of an array antenna and INS is shown in Appendix Figure 1 as follows; The working flowchart of satellite navigation spoofing interference detection based on the fusion processing of an array antenna and INS is shown in Appendix Figure 2 as follows. In a specific embodiment, strong spoofing suppression interference at the BDS B3 frequency point, medium-intensity dual-antenna air-repeater spoofing interference, low-intensity generative spoofing interference of satellites No. 24 and No. 59, and repeater spoofing interference of satellites No. 31 and No. 32 are selected as complex spoofing scenarios, and the steps of the method for detecting satellite navigation spoofing interference based on the fusion processing of an array antenna and INS are as follows:

[0033] Step 1: Based on the existing array antenna architecture and design of the navigation and positioning device, start the power detection module in adaptive nulling spatial filtering to identify the power of strong spoofing interference in space. If it is detected that the power of the interference signal in space exceeds the power of the noise signal, it is determined that there is jamming interference or high-intensity suppression spoofing signal in space. Mark the status of the spoofing signal and start the adaptive nulling function to suppress high-intensity suppression spoofing. If it is detected that there is a satellite navigation signal with a power exceeding the noise spectrum signal power, it is determined that there is strong spoofing interference in space. Mark the status of the spoofing signal and start the adaptive nulling function to perform adaptive nulling suppression on the strong spoofing interference, and record and store the relevant spoofing interference status.

[0034] Step 2: Based on the INS attitude assistance information and the space satellite almanac information, form beam pointing to the space satellites. A total of 12 beam pointings are formed to the space satellites, and signal acquisition is performed on the satellite numbers within the beams. Among them, there are two correlation peaks for satellite numbers 24 and 27 in beams 4 and 9, and the carrier-to-noise ratio of the correlation peaks is 83 dB·Hz, both higher than the threshold of 45 dB·Hz after beam synthesis. It is determined that there is spoofing interference for satellite numbers 24 and 27. At the same time, there are correlation peaks of 12 satellites within beams 4 and 9, and the carrier-to-noise ratio of the correlation peaks is 82 dB·Hz, exceeding the normal power threshold of 42 dB·Hz for satellites. Nulls are actively formed at the positions of beams 4 and 9 to suppress the interference, and the signal acquisition and power detection processes are restarted. After signal acquisition processing, the correlation peaks of the 12 satellites during beam formation disappear and cannot be normally acquired. Therefore, it is determined that there is medium-intensity spoofing interference at the positions of beams 4 and 9. Mark the spoofing signal at this airspace position and form an active null to suppress the spoofing interference, and record and store the relevant spoofing interference status.

[0035] Step 3: The navigation and positioning device resumes the normal beam synthesis and active nulling suppression working mode and starts the low-intensity spoofing interference detection process. First, perform signal acquisition processing on the satellites pointed by the beams, and complete the signal domain acquisition and identification of the spoofing signal through the multi-correlation peak detection of the satellite numbers; complete the signal domain tracking and identification of the spoofing signal through the detection of the satellite signal power threshold. If no low-intensity spoofing interference is identified through multi-correlation peak and power detection, the device then enters the normal signal tracking working stage, perform cross-differences on the inter-beam pseudoranges of all visible satellites, perform cross-differences on the pseudoranges of the same satellite number between different frequency points, and perform cross-differences on the pseudorange rates of all received satellites based on the INS. It is found that for satellites with satellite numbers 24 and 59, there is data stratification in the cross-difference between the pseudorange change rates of these satellites and those of other satellites, and the two are inconsistent. Therefore, it is determined that there are low-intensity spoofing interference signals for satellite numbers 24 and 59, and record and store the relevant spoofing interference status.

[0036] Step 4, on the basis of completing signal domain spoofing detection, detect possible missed alarm spoofing interferences through information domain detection. Use the pseudorange observables output by space satellite signal tracking to perform multi-satellite autonomous integrity residual detection and satellite clock jitter anomaly detection verification. Through calculation and iteration, during the autonomous integrity residual detection of satellites numbered 31 and 32, the pseudorange observable residual is 102, exceeding the predetermined threshold of 20. At the same time, perform clock jitter anomaly iterative calculation. After calculation, the clock differences of satellites numbered 31 and 32 are 67, also exceeding the predetermined threshold of 15. Therefore, it is determined that the satellite signals of satellites numbered 31 and 32 are spoofing signals, and their satellite numbers are marked. Through the above steps, all spoofing signals are identified, detected, recorded, and alarm output is completed. Finally, through the full-dimensional domain processing of the fusion of the array antenna and INS, online real-time seamless full coverage and efficient detection of various complex spoofing interference scenarios of the positioning device are completed.

[0037] The present invention proposes a method for detecting multi-intensity, multi-style, multi-level, and full-dimensional domain spoofing interferences in satellite navigation based on the fusion processing of an array antenna and INS. This method is based on the existing array antenna and INS platform of the satellite navigation positioning device, does not require the construction of additional conditions and environmental support for spoofing detection, does not require changing the existing hardware architecture of the positioning device, and does not require external auxiliary information. The detection of spoofing interferences runs through the entire working process of the navigation positioning device. And the detection of spoofing interferences is divided into airspace detection, signal domain detection, and information domain detection, and a multi-means joint processing method is adopted to achieve seamless coverage of the three-dimensional full-dimensional domain of spoofing interference detection.

[0038] First, utilize the active nulling and adaptive nulling filtering functions of the array antenna to suppress the strong spoofing interference identified in space. Then, use the INS attitude-aided information and satellite ephemeris information to form the beam pointing, perform correlation peak detection and identification on the multiple correlation peaks of the same satellite within the beam and multiple satellites in the same beam. Based on the design of the active nulling, verify the spoofing signals existing in the beam pointing through the nulling suppression method, identify the medium-strength spoofing interference in space and mark it. The navigation and positioning device resumes the normal working mode, performs signal acquisition and tracking on the space satellites in the signal domain, and obtains the observation quantities such as the correlation peaks, signal carrier-to-noise ratio, and pseudorange of the satellites. Detect the low-strength spoofing interference signals through the identification of multiple correlation peak detection and power detection. At the same time, complete the spoofing of all visible satellites participating in the positioning solution through the detection of pseudorange consistency between multiple beams, pseudorange consistency between dual frequencies, and pseudorange change consistency based on INS negative assistance, and mark the abnormal low-strength spoofing signals. After completing the spoofing detection in the signal domain, in order to ensure the integrity and reliability of the spoofing signal detection, detect the possible undetected spoofing interference through the detection method in the information domain. Use the autonomous integrity residual detection and clock difference anomaly detection methods in the information domain to detect the spoofing of the observation quantities of the satellites participating in the positioning. If there are satellite numbers with autonomous integrity and clock difference jitter residuals exceeding the threshold, identify them as spoofing signals. Finally, complete the identification, detection, recording, and alarm output of all spoofing signals through the full-dimensional domain processing method of the fusion of the array antenna and INS. This method realizes spoofing interference detection by adopting the fusion method of the array antenna, INS, and full-dimensional domain processing, has a wide application range, and is not restricted by spoofing patterns and spoofing intensities; whether the spoofing signal is a strong spoofing interference suppression, medium spoofing interference blocking, low-strength spoofing interference luring, etc., with multiple intensity levels of spoofing interference, or single-antenna spoofing, multi-antenna spoofing, generative spoofing, retransmitted spoofing, etc., as well as various combinations of spoofing interference of various patterns, this method is effective and has a high spoofing detection success rate.

[0039] The present invention adopts the method of array antenna, INS, and multi-dimensional domain signal fusion processing, which can achieve seamless full-dimensional domain coverage for multi-intensity, multi-pattern, and multi-level spoofing interference. The detection method is reliable and has high accuracy. This method is based on the existing array antenna and INS hardware architectures, does not require the construction of additional conditions and environmental supports, and does not require external auxiliary information. It is simple to implement in engineering and has strong updatability. Adopting the multi-dimensional domain redundant check detection method, the undetected alarm rate of spoofing interference is low, comprehensively improving the integrity and robustness of the navigation and positioning device. Compared with the traditional spoofing detection based on the array antenna, the spoofing detection result is more robust and reliable, and is applicable to application fields with high security requirements such as civil aviation.

[0040] The embodiments described above are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

Claims

1. A satellite navigation deception interference detection method based on the fusion processing of array antennas and INS, characterized in that The method comprises the following steps: S1) The active nulling and adaptive nulling unit based on the spatial domain detection of the array antenna performs power identification on strong spatial spoofing jamming, and at the same time cooperates with the beam pointing to identify strong spatial spoofing jamming; if there is a satellite navigation signal with a power exceeding the noise spectrum signal power, it is determined that there is strong spoofing jamming in the space, the corresponding satellite navigation signal is state-identified, and the adaptive nulling function is started to adaptively null and suppress the strong spoofing jamming; if no strong spoofing jamming is detected, it is determined that there is no strong spoofing jamming in the space, and the process continues to the next stage of spoofing jamming detection; S2) The beam weight is generated by using the attitude auxiliary information of the inertial navigation system INS and the satellite ephemeris information, and the array antenna synthesizes a beam to form a beam pointing to the satellites received in the space, improving the signal reception gain of the satellites received in the space and forming beam suppression for the signals in the airspace outside the satellite direction; the signal acquisition process of the device is started, multi-correlation peak detection and signal power detection are performed on the satellites within the beam pointing. If there are multiple correlation peaks for the same satellite within the same beam, and the signal power intensity of some of the correlation peaks exceeds the threshold of the normal spatial signal, it is determined that there is medium spoofing jamming in the signal reception space, and the relevant signals are identified and displayed; continue to perform signal acquisition for the satellites within the beam pointing. If there are correlation peaks for multiple satellites within the same beam, and the signal power intensity of the satellites all exceeds the maximum threshold of the normal spatial satellite signal, the active nulling of the spatial domain detection is started for identification, and active nulling suppression is formed in the original beam pointing. If after the active nulling is started, all the correlation peaks of the satellites disappear or the signal power decreases by more than 30 dB, it is determined that there is medium spoofing jamming in the space, and the spoofing signals are identified and displayed; otherwise, there is no medium spoofing jamming in the space, and the process continues to the next stage of spoofing jamming detection; S3) The array antenna resumes the beam pointing working mode and starts the low-intensity spoofing interference detection process for the next stage. First, multiple beams point to the satellite for signal acquisition. Through the multi-correlation peak detection in signal acquisition, spoofing interference is identified. If there are multiple correlation peaks for a single satellite, it is determined that there is low-intensity spoofing interference in the signal reception space, and the relevant signals are marked and displayed. Then, it enters the signal tracking stage, tracks the satellites received in space, and discriminates the signal power of the satellites. If the signal power of a satellite exceeds the threshold of the real satellite, it is determined that the satellite signal is low-intensity spoofing interference, and the spoofing signal is marked and displayed. Finally, data monitoring methods including inter-beam pseudorange consistency, inter-frequency pseudorange consistency, and INS-assisted pseudorange change consistency are performed on the observables output by satellite tracking to detect low-intensity spoofing interference that may be missed. If the detection results of inter-beam pseudorange consistency, inter-frequency pseudorange consistency, and INS-assisted pseudorange change consistency for the same satellite are inconsistent, it is determined that the satellite is low-intensity spoofing interference, and the spoofing signal is marked and displayed. Otherwise, there is no low-intensity spoofing interference and missed-alarm spoofing interference in space, and it continues to enter the spoofing interference detection process for the next stage; S4) Finally, using the spoofing interference detection results of steps S1)-S3), multi-satellite autonomous integrity residual detection and satellite clock error jitter anomaly detection and verification are performed on the possible missed-alarm spoofing interference through the information domain spoofing interference detection method, using the pseudorange observables output by space satellite signal tracking. If the autonomous integrity residual detection result of a certain satellite exceeds the threshold or the satellite clock error jitter exceeds the threshold, it is determined that the satellite signal is a spoofing signal, and the spoofing signal is marked and displayed. Otherwise, there is no spoofing signal in space; through information domain spoofing interference detection, the possible missed-alarm spoofing interference in steps S1)-S3) is supplemented and verified again, and finally, the identification, detection, recording, and alarm output of all spoofing signals are completed; Through the above steps, multi-level and full-dimensional real-time online detection of all types of satellite navigation spoofing interference is completed.

2. The satellite navigation spoofing interference detection method based on the fusion processing of an array antenna and INS according to claim 1, wherein In step S1), based on the architecture of the existing array antenna navigation and positioning device, without changing the array antenna hardware platform of the traditional device and without changing the device working process, based on the existing active nulling and adaptive nulling processing design in the adaptive filtering unit of the array antenna, combined with the beam pointing function, strong spoofing interference existing in space is detected and suppressed. The strong spoofing interference is detected by identifying the power of the spoofing interference. If there is high-intensity suppression spoofing interference, it is directly marked and the strong spoofing interference is suppressed through active nulling. If not, it enters the spoofing detection process of step S2).

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