Altitude Estimation of Missile-borne Radar Seeker Based on Front-downward View and Range-Doppler Analysis

The altitude of the missile-borne radar seeker relative to the illuminated region is a significant parameter for the geometric correction in synthetic aperture radar (SAR) imaging. Error in altitude causes geometric distortion, which affects the performances of the subsequent scene matching and the target identification in SAR. Conventional radar altimeter with the down-looking antenna is not appropriate for missile-borne radar seeker with the forward antenna. To circumvent this problem, a Range-Doppler based Altitude Estimation algorithm (RDAE) appropriate for front-downward illumination is proposed based on the geometrical relationship between the relative altitude and the Range/Doppler between the platform and the illuminated region. The performance of the RDAE is investigated through simulation, and the results show that the RDAE has high estimation accuracy.