Direction-of-arrival estimation of FM sources based on robust spatial time-frequency distribution matrices

We consider robust Direction-Of-Arrival (DOA) estimation of frequency modulated sources impinging on a sensors' array. DOA estimation based on standard spatial time-frequency distributions (STFDs) fails in the presence of impulsive noise. We propose two approaches to robustify the estimation. The first approach is based on pre-processing the observations to reduce and suppress impulsive interference. The second approach uses a weighted STFD estimation where the weights are based on the distance of the observations from the center of the majority of the data. The efficacy of the proposed methods is shown via simulations where an improvement of the estimation in the presence of impulsive noise is obtained. Both methods offer good robustness while being simple and easy to implement.