Robust DOA Estimation for Sources With Known Waveforms Against Doppler Shifts via Oblique Projection

Abstract

As known, utilization of the information about signal waveforms can improve the direction-of-arrival (DOA) estimation results. However, with a fast moving platform, the Doppler effect occurs, which distorts the known waveforms and may result in large DOA estimation bias and even errors for conventional DOA estimation methods for sources with known waveforms. To deal with this problem, a robust DOA estimation method for sources with known waveforms against Doppler shifts is developed. The proposed method first transforms the nonlinear mixing of Doppler shifts in the model to an approximately linear one using discrete-time Fourier transform and finite Taylor series expansion. Then, multiple oblique projectors are constructed to separate each component corresponding to different order of derivatives. Finally, estimations of DOAs, complex amplitudes, and Doppler shifts are obtained simultaneously. Simulation results show that the proposed method has a much more robust DOA estimation performance than existing methods for sources with known waveforms.