Research On Projectile Position Measurement Technology Based On Satellite/PSD

The traditional laser-guided weapons have high accuracy in hitting the target,high battlefield value and considerable operational performance.However,the disadvantages like high cost and complex structure make it difficult for countries to achieve the goals of completed and precise guidance of weapon equipment.The modern warfare has increasingly requirements of cost-effectiveness ratio of battlefield ammunition.Therefore,the cost down and accurate reconstruction of traditional uncontrolled ammunition has become a hot research topic in recent years.Based on the position sensitive detector and satellite navigation and positioning technology,the attitude measurement and positioning of projectile and target are studied in this paper.Position sensitive detector is used to calculate the roll angle and line-of-sight angle of the projectile.Satellite positioning technology is used to locate the projectile,and then the pitch angle and yaw angle of the projectile are calculated according to the small angle of attack theory.Finally,target tracking and positioning can be completed according to the position and attitude information of the projectile and the line-of-sight angle of the projectile.(1)In order to improve the battlefield adaptability of the projectile and ensure the normal operation of the satellite navigation system,based on the characteristics of laser semi-active guided projectile platform,two conformal quadrifilar helical antennas and the corresponding feeding network are designed on the surface of the optical lens,which can cover the GPS L1 and Beidou B3 frequency bands at the same time.Finally,the dual-frequency quadrifilar helical antenna with better performance is selected for processing,meanwhile the satellite positioning test is carried out on site.The experimental results show that the antenna has a high signal-tonoise ratio in the positioning test and can achieve good positioning results in all directions of missile.(2)In order to reduce the design cost and the complexity of the system,only the satellite navigation system and position sensitive detector are used to measure the position and attitude information of the projectile.Satellite positioning technology is used to locate the projectile position,and then the pitch angle and yaw angle of the projectile are calculated based on the small angle of attack.Use a position sensitive detector(geomagnetism is only used for initial value acquisition and auxiliary measurement)to calculate the rolling angle of projectile.Due to the large error of calculation data,elm algorithm is used to predict the projectile attitude information.Then Kalman filter is used to estimate the optimal value of the projectile attitude information.The simulation results show that this algorithm can significantly reduce the error of the projectile attitude information.(3)In order to locate the target,height angle and line-of-sight azimuth of the target relative to the projectile are calculated by the position-sensitive detector.The advantages and disadvantages of target location research are analyzed.According to the information of projectile position,attitude and line-of-sight angle,an autonomous target location method based on the line-of-sight intersection model is proposed.Then a target positioning error model is established,which directly reflects the influence of various parameters on the final positioning error.The simulation results show that the projectile positioning error is less than 5 meters after capturing the target for 2.5 seconds.