Joint High-Resolution Delay-Doppler Estimation for Bi-static Radar Measurements

This contribution describes a maximum-likelihood based joint delay-Doppler estimation algorithm for bi-static radar measurements. The data model used by the estimator considers delay and Doppler of multiple propagation paths explicitly. As we aim at considering typical signals used for communications, the transmit signal is rather long compared to signals in channel sounding. Therefore, the Doppler shift has to be modeled as a linearly changing phase within a single symbol. The derivation of an iterative Gauss-Newton algorithm to solve the resulting least-mean-squares problem is shown. The model order is determined dynamically by means of the Fisher information matrix and the Cramér-Rao lower bound. The functionality is shown using measurements of a bi-static radar in a semi-anechoic chamber.