Motion Compensation Method for Uniformly Accelerated Moving Targets by Frequency-Coded Waveform Based on DFDS

Frequency-coded radars have the potential to enable joint high-resolution range-Doppler estimation. However, efficient estimation of multi-target parameters based on frequency-coded waveform remains a challenge. In this paper, an algorithm is proposed to estimate velocities and accelerations of multiple targets and generate high-range-resolution profiles(HRRP) of targets using different frequency pulses. In motion parameters estimation, a set of signals with constant range phase terms and varying motion parameters phase terms are constructed by setting certain difference-frequency parameters, and then these signals are used to generate a new generalized Doppler spectrum, which is called Difference-Frequency Doppler Spectrum(DFDS). In order to suppress the rise of noise floor in DFDS caused by the sidelobes and cross-terms, the DFDS corresponding to different difference frequency parameters are accumulated to obtain the accumulated DFDS. From the accumulated DFDS, the targets are detected and their velocities and accelerations are estimated. Then the estimated values of motion parameters are utilized for motion compensation, and the HRRPs of the targets are generated by range matched filtering. The method proposed in this paper estimates motion parameters in two dimensions, which is one more dimension than the methods only estimating velocity, applicable to uniformly accelerating moving targets scenario and able to provide more accurate HRRPs of targets.