Least-Squares Range Measurement of FM Ranging Radar for Maneuvering Target

This paper introduces a least squares (LS)-based method designed to enhance the accuracy of range measurements in frequency modulated interrupted continuous wave (FMICW) pulse-Doppler radars, specifically addressing the challenge of accurately tracking highly maneuvering targets. Conventional FM ranging methods assume constant velocity within dwell periods, leading to significant biases in range estimation when targets experience rapid acceleration or jerk. Our proposed approach incorporates acceleration and jerk parameters into the radar measurement model, utilizing multiple FMICW bursts with varied slopes to jointly estimate range, velocity, and higher-order motion parameters. Theoretical analyses, supported by the calculation of the Cramér-Rao bound, demonstrate the method's superior estimation accuracy and optimality. Simulation and flight test results using an X-band AESA radar system validate the method's effectiveness, showing a substantial reduction in range bias and enabling earlier and more reliable target detection compared to conventional methods.