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CN-121978715-A - Satellite navigation anti-deception method based on dynamic trend characteristics

CN121978715ACN 121978715 ACN121978715 ACN 121978715ACN-121978715-A

Abstract

The application provides a satellite navigation anti-deception method based on dynamic trend characteristics, which comprises the steps of constructing two short-time sliding window arrays based on an inertial navigation pure inertial positioning signal sequence and a satellite navigation positioning signal sequence respectively, dynamically updating data in a window along with the arrival of a positioning signal at a new moment, wherein the moment of the current data is The total duration of data in the window is To Respectively establishing two north-east-ground coordinate systems by taking the moment pure inertial positioning signal and the guard positioning signal as the origin of coordinates, respectively calculating the inertial navigation pure inertial positioning signal and the guard positioning signal in a short-time window array Time positioning signal and space coordinate system origin, namely short time window The method comprises the steps of determining a three-dimensional space vector between time positioning signals, calculating cosine similarity based on the three-dimensional space vector to represent trend consistency between two positioning signal sequences, judging a threshold value and dynamically adjusting so as to output an alarm, and effectively improving the survivability of the guard carrier in a complex electromagnetic environment and the reliability of task execution.

Inventors

  • ZHU ZIFA
  • GUO TONG
  • LI YUNXIA
  • XIAO YONG
  • YANG LIN
  • TAO CHENGGANG

Assignees

  • 中国航空工业集团公司成都飞机设计研究所

Dates

Publication Date
20260505
Application Date
20251227

Claims (8)

  1. 1.A satellite navigation anti-fraud method based on dynamic trend features, the method comprising: Step 1, respectively collecting Time inertial navigation pure inertial positioning signal And guard positioning signal ; Step 2, respectively utilizing short time windows All inertial navigation pure inertial positioning signals in time And guard positioning signal Two sliding window arrays are constructed: Step 3, by Pure inertial positioning signal for moment inertial navigation measurement And guard positioning signal Respectively establishing two north-east-ground coordinate systems for the origin of coordinates; step 4, respectively calculating inertial navigation pure inertial positioning signals and guard positioning signals in a short-time window array Time positioning signal and space coordinate system origin, namely short time window Three-dimensional space vectors between time positioning signals; Step 5, calculating cosine similarity based on the three-dimensional space vector; And 6, judging and dynamically adjusting the threshold value, and outputting an alarm based on the threshold value.
  2. 2. The method according to claim 1, wherein the step 1 further comprises: And ensuring that the inertial navigation pure inertial positioning signal is aligned with the guard positioning signal through time stamp synchronization.
  3. 3. The method according to claim 2, wherein the step 2 comprises: setting the frequency of the input signal to 10HZ, namely collecting a position signal every 100ms, and constructing a sliding window with the total duration of ; Using all inertial navigation pure inertial positioning signals in short-time window And guard positioning signal Two sliding window arrays can be constructed separately: With the input of new time data, the array is dynamically updated and the short time window The duration of (2) is adjusted according to the motion characteristics of the carrier.
  4. 4. A method according to claim 3, wherein said step 4 comprises: Based on the WGS-84 model, three-dimensional space vectors between the last point in the short-time window array of the inertial navigation pure inertial positioning signal and the satellite navigation positioning signal and the first point in the space coordinate system origin, namely the short-time window, are calculated respectively.
  5. 5. The method of claim 4, wherein the calculating three-dimensional space vectors between the last point in the array of short-time windows of the inertial navigation positioning signal and the satellite navigation positioning signal and the origin of the space coordinate system, i.e., the first point in the short-time window, based on the WGS-84 model, respectively, comprises: taking the fixed value of the earth radius as 6371288, and the distance from the origin of the space coordinate system of the position of the satellite navigation positioning to the sphere center of the earth is as follows: ; difference of two-point north coordinates The method comprises the following steps: ; correction of difference between east coordinates of two points The method comprises the following steps: ; Difference of east coordinates of two points The method comprises the following steps: ; Difference of two-point geodesic coordinates The method comprises the following steps: ; the three-dimensional space vector of the final guard positioning signal is ; The three-dimensional space vector of the inertial navigation positioning signal obtained by the same method is 。
  6. 6. The method according to claim 5, wherein said step 5 comprises: If the guard positioning signal is deceived, the positioning result will deviate, the actual track trend of the moving carrier is inconsistent with the track trend of the guard positioning, and in a short time, the inertial navigation pure inertial positioning signal just can represent the trend of the real motion of the carrier, therefore, when the guard positioning is deceived, the inertial navigation pure inertial positioning track vector and the guard positioning track vector have certain included angle, namely the track vector trend is inconsistent, and the cosine similarity is high The similarity of the directions between the two vectors can be quantitatively measured, and the calculation formula is as follows: the range of cosine similarity is [ -1,1],1 indicates that the directions are completely consistent, 0 indicates that the directions are orthogonal without correlation, and-1 indicates that the directions are completely opposite.
  7. 7. The method of claim 6, wherein the performing the threshold determination and dynamic adjustment comprises: the speed information output by the inertial navigation pure inertial positioning signal has higher reliability and is not influenced by external interference and deception signals, so the total speed of the carrier is calculated through the speed signal output by the inertial navigation pure inertial positioning signal Judging the maneuvering state of the guide carrier through the total speed; in order to avoid that the carrier is forbidden to move and the cosine similarity cannot be calculated, the movement speed of the carrier is set to be more than or equal to Therefore, taking different trend detection thresholds based on the total speed of flight and the divide by zero protection is: 。
  8. 8. The method of claim 7, wherein the alerting outputting based on the threshold comprises: alarm signal when And sending an alarm signal, wherein the flight control system can be switched to a pure INS navigation mode so as to prevent the carrier from being decoy to cause task failure or carrier runaway.

Description

Satellite navigation anti-deception method based on dynamic trend characteristics Technical Field The application belongs to the technical field of satellite navigation, and particularly relates to a satellite navigation anti-deception method based on dynamic trend characteristics. Background Satellite navigation systems (GNSS) are an important navigation technology, which can provide precise position, velocity and time (PVT) information for carriers such as automobiles, ships, airplanes, etc., and support the carriers for navigation control, path planning, and task execution. The most widely applied satellite navigation is easy to be interfered and deception, the existing deception detection method (such as abnormal star detection and signal-to-noise ratio mutation detection) is invalid for a forward deception source for forwarding real signals, a pure Inertial Navigation System (INS) has anti-interference characteristics, but has error accumulation characteristics, navigation accuracy is degraded along with time and cannot provide time information, and the combined inertial navigation and defending navigation system also faces the pollution risk of deception signals, and the defending abnormal signals can directly cause state estimation deviation no matter in a loose coupling algorithm or a tight coupling algorithm. Disclosure of Invention The invention aims to provide a satellite navigation anti-deception method based on dynamic trend characteristics, which effectively improves the survivability of a satellite navigation carrier in a complex electromagnetic environment and the reliability of task execution and provides a key technical guarantee for accurate navigation in a high threat scene. The application provides a satellite navigation anti-deception method based on dynamic trend characteristics, which comprises the following steps: Step 1, respectively collecting Time inertial navigation pure inertial positioning signalAnd guard positioning signal; Step 2, utilizingAll inertial navigation pure inertial positioning signals in timeAnd guard positioning signalTwo sliding window arrays can be constructed separately: Step 3, by Pure inertial positioning signal for moment inertial navigation measurementAnd guard positioning signalRespectively establishing two north-east-ground coordinate systems for the origin of coordinates; Step 4, respectively calculating the inertial navigation pure inertial positioning signal and the guard positioning signal in the short-time window array Time positioning signal and space coordinate system origin, namely short time windowStep 5, calculating cosine similarity based on the three-dimensional space vectors; And 6, judging and dynamically adjusting the threshold value, and outputting an alarm based on the threshold value. Preferably, the step 1 further includes: And ensuring that the inertial navigation pure inertial positioning signal is aligned with the guard positioning signal through time stamp synchronization. Preferably, the step 2 includes: setting the frequency of the input signal to 10HZ, namely collecting a position signal every 100ms, and constructing a sliding window with the total duration of ; Using short time windowsAll inertial navigation pure inertial positioning signals in timeAnd guard positioning signalTwo sliding window arrays can be constructed separately: With the input of new time data, the array is dynamically updated and the short time window The duration of (2) is adjusted according to the motion characteristics of the carrier. Preferably, the step 4 includes: Based on the WGS-84 model, three-dimensional space vectors between the last point in the short-time window array of the inertial navigation pure inertial positioning signal and the satellite navigation positioning signal and the first point in the space coordinate system origin, namely the short-time window, are calculated respectively. Preferably, based on the WGS-84 model, calculating three-dimensional space vectors between a last point in the short-time window array of the inertial navigation positioning signal and the satellite navigation positioning signal and a space coordinate system origin, i.e. a first point in the short-time window, respectively, includes: taking the fixed value of the earth radius as 6371288, and the distance from the origin of the space coordinate system of the position of the satellite navigation positioning to the sphere center of the earth is as follows: ; difference of two-point north coordinates The method comprises the following steps:; correction of difference between east coordinates of two points The method comprises the following steps:; Difference of east coordinates of two points The method comprises the following steps:; Difference of two-point geodesic coordinates The method comprises the following steps:; the three-dimensional space vector of the final guard positioning signal is ; The three-dimensional space vector of the inertial navigation posi