Research On The Influence And Suppression Method Of Phased Array Radar Guided Parasitic Loop

Strap-down Phased-Array-Radar Seeker has fast scanning ability?flexible beam?distributable power. Strap-down Phased-Array-Radar seeker is fixed on the missile body, so the rate gyro is needed to decouple missile motion from the seeker, so as to get the Line-Of-Sight rate in the inertial frame. In the decoupling process, the disturbance rejection rate problem, which is caused by the difference between the diving rulers of the seeker's measurement system and the rate gyro, may badly affect the missile's guidance performance.This study aims at the Strap-down Phased-Array-Radar Seeker, main works are as follows: Analyzed the main cause of the disturbance rejection rate problem based on the phased-array-radar seeker's operating principle. Build models of the disturbance rejection rate and its parasitic loop. Non-dimensional the disturbance rejection rate parasitic loop and the guidance loop of the missile guided by proportional guidance, using the Routh-Rule to analyze their characteristics of stability; Analyzed the effect of the parasitic loop on some importance guidance parameters. Used the Method of Adjoints to analyze the disturbance rejection rate's effect on the miss distance caused by different error sources. Proposed two approaches to solve the disturbance rejection problem: One is to estimate the radome slope by adding high frequency dither to the autopilot and by using the band filter, then compensate the estimated radome slope. The other is to estimate the main parameter in beaming system that caused the disturbance rejection rate problem by using the Extended Kalman Filter, and then compensate it.