Research On Spoofing Suppression Technology Based On GNSS/SINS Tightly Integrated Navigation System

In modern warfare,various weapons and equipment depend on the precise position,speed and time provided by the global navigation satellite system(GNSS).However,due to the vulnerability of satellite navigation signals,the receiver is susceptible to human interference.Especially,the forwarding spoofing may induce the receiver to the wrong position.Therefore,this paper used strapdown inertial navigation system(SINS)to form a GNSS/SINS tight integrated navigation system.Aiming at the spoofing of dynamic time-delay,the paper studied the detection and suppression methods of forwarding spoofing.The main research contents of the paper are as follows:1.In order to provide a basic platform for algorithm development and simulation for research on forwarding spoofing detection and suppression methods based on GNSS/SINS tightly integrated navigation system,the paper studied the positioning and speed measurement principles of GNSS,SINS,and GNSS/SINS tight integrated navigation systems.2.In order to analyze the influence of forwarding spoofing on GNSS/SINS tight integrated navigation system,the paper introduced the theoretical model of forwarding spoofing.The forwarding spoofing included two types:one had fixed time-delay characteristics,and the other had dynamic time-delay characteristics.The paper analyzed the influence of two kinds of forwarding spoofing on the parameters of GNSS/SINS tight integrated navigation system.These parameters included position,speed,pseudorange,pseudorange rate and residual.The paper discussed the rationality of designing detection parameters based on residuals.3.The paper proposed the residual sliding variance detection parameters,and the forwarding spoofing detection method based on GNSS/SINS tight integrated navigation system.Aiming at forwarding spoofing with fixed time-delay,the paper used its fixed time-delay characteristics to propose a detection method based on pseudorange residual time-delay characteristics.The simulation results show that the method can detect forwarding spoofing with fixed time-delay within 0.1s.This method is effective in forwarding spoofing with fixed time-delay where the pseudorange deviation is not less than 14.7m.Aiming at forwarding spoofing with dynamic time-delay,the paper used its fixed and dynamic time-delay characteristics to propose a detection method based on residual time-delay characteristics.The simulation results show that the method can detect forwarding spoofing with dynamic time-delay within 0.1s.This method is effective in forwarding spoofing with dynamic time-delay where the pseudorange rate deviation is not less than 2.94m/s.4.The paper proposed a suppression method based on the measured true value fitting.By deriving the mathematical relationship between the estimated value of residual and the measured true value,the paper proposed a suppression method based on the measured true value fitting.In order to prove the superiority of this method,the paper designed two methods as control methods.The simulation results show that the method proposed in the paper can meet the basic positioning accuracy requirements when the number of real satellites is more than two,and it can improve the anti-spoofing interference performance of the tightly integrated system.Besides,the method proposed in the paper has higher positioning and speed measurement accuracy.When the number of real satellites is more than two,the position error of the method proposed in the paper,compared with the two control methods,the position errors are reduced by more than 70%,and the velocity errors are reduced by more than 40%in the north and east.