An algorithm for estimating time-varying Doppler at low SNR

This paper presents an algorithm for estimating the time-varying Doppler return signal from a target which has a time-varying acceleration, with this changing acceleration being modeled as a linear function of time. The method involves modeling the return signal as the sum of a number of constant amplitude cubic phase signals embedded in noise. An algorithm is presented for estimating the phase parameters and subsequently the time-varying Doppler (under the assumption that the Doppler shift is small compared with the center frequency of the irradiation). Simulations are presented to confirm the effectiveness of this algorithm.