| In today’s world,the battlefield environment is becoming more and more complex,and concealed investigation has become an important strategy to improve the survivability and combat capability of modern electronic warfare system.Traditional active detection devices are less concealed and vulnerable to enemy attacks.Passive location technology is a technology that locates the radiation source only by passively receiving the radiation signal from the radiation source.Passive detection equipment has a long range of detection and good concealment,and is an important weapon to "preempt" the enemy.Because of its wide application range and high flexibility,airborne single-observer passive location has become an important research direction in passive locating technology.Based on the background of passive locating of stationary or moving targets by high-speed air observation platform,the passive locating technology of airborne single-observer is studied from the following aspects:1.The research background of this paper is introduced,and the significance of singleobserver passive locating technology in airborne is discussed.The research status and development trend of single-observe passive locating technology at home and abroad are combed.2.The basic principles of phase difference rate of change location and Doppler frequency change rate location are introduced in detail,and the observability of the two passive positioning methods are analyzed.Combining theoretical analysis with computer simulation,the effect of the size of each observation and the precision of parameter measurement on the relative locating error is studied in a two-dimensional plane.Based on the actual situation,appropriate simulation models are established,and the locating effects of the two singlestation passive locating methods are verified by simulation and error analysis.3.It is difficult for the existing angle measurement system to meet the requirements of highprecision positioning.In order to solve this problem,a new method of calculating pitch angle and its rate of change is proposed.In the traditional airborne single station passive positioning system,each antenna element is in the plane of the fuselage.In the algorithm proposed in this paper,one phase interferometer is in the plane of the fuselage,and the other phase interferometer is perpendicular to the plane of the fuselage.The angle and angle change rate information can be measured indirectly by the amplification of phase difference change to the angle and phase difference change rate to the angle change rate.The simulation results show that,without reducing the accuracy of azimuth and azimuth rate of change,the accuracy of pitch angle and its rate of change is greatly improved by using this method.The computer simulation is used to analyze the calculation results of the difference method and Kalman filter method to extract the phase difference rate of change.The simulation results show that the accuracy of the phase difference rate of change obtained by the Kalman filter method is significantly higher than that obtained by the difference method.Therefore,the application of the Kalman filter method is of great significance to the improvement of the calculation accuracy of pitch angle and its rate of change.4.In this paper,the advantages and disadvantages of phase difference rate of change and Doppler frequency rate of change are analyzed synthetically.By using the amplification effect of phase difference on angle and phase difference rate of change on angle rate of change,combined with the two positioning methods,the joint positioning method based on phase difference,phase difference rate of change and Doppler frequency rate of change is studied.Through theoretical analysis and computer simulation analysis,the influence of the measurement size and the measurement accuracy of the parameters on the relative positioning error is discussed.An appropriate simulation model is established to verify the positioning effect of the joint positioning method based on phase difference,phase difference rate of change and Doppler frequency rate of change.On the premise of the same parameter measurement accuracy,the positioning accuracy of the passive positioning method for static and moving targets is compared.It can be seen from the simulation results that after using the pitch angle and its rate of change solution method proposed in this paper,the joint positioning method can greatly improve the positioning accuracy of static and moving targets,both of which have high positioning accuracy. |
