Initial trajectory parameters in the presence of range-Doppler coupling error

Abstract

This paper focuses on obtaining our initial estimates for a Kalman filter. The Kalman filters are applied to estimate the motion parameters of objects detected by chirp radars. Chirp radars employ linear frequency modulated (LFM) waveforms for object tracking because the range-Doppler coupling allows better tracking accuracy in the range. The issues of initial trajectory parameters as a function of the range-Doppler coupling coefficient are discussed. Technically significant conditions of the same characteristics of the radar and the objects and equal deviations of the LFM signals in modulus at the moments of probing are used to form several measurements of the detected trajectory. Under the above conditions, there are 4 methods of determining the signs of the range-Doppler coupling coefficients for three measurements. The initial parameters of the trajectory for the second-order filter based on the three measurements are compared with each other at the methods of determining the signs of the range-Doppler coupling coefficients. The method l = 3 of determining the signs of the range-Doppler coupling coefficients (sign-variable the range-Doppler coupling coefficients) is advantageous because the normalized coordinates estimation variances take the smallest values compared to the other methods.