Research on wingtip distance measurement of high-speed coaxial helicopter based on 77 GHz FMCW millimeter-wave radar

Abstract

Aiming at the requirements of short-range, high-precision, and high-speed measurement of coaxial helicopter wingtip distance measurement, a millimeter-wave radar wingtip distance measurement scheme is proposed, and the ranging accuracy of frequency-modulated continuous wave millimeter-wave radar is improved by optimizing the frequency estimation method and the beat-frequency signal processing process. The multi-antenna data coherent superposition method and the correlation search for the estimated frequency are used to shorten the measurement period, and at the same time, the ranging accuracy of the millimeter-wave radar can be improved, and the single measurement time can be guaranteed. Based on frequency refinement, frequency offset method, phase method, amplitude method and fitted approximation method, the frequency estimation of millimeter wave radar differential frequency signal is combined with the influence of bandwidth, measured target shape and material on ranging to improve millimeter wave radar ranging performance comprehensively. Through simulations and experiments, the accuracy, stability, time consuming and application conditions of the optimized algorithm are comprehensively evaluated, and the feasibility of millimeter wave radar wingtip ranging is verified.