Abstract: The DOA estimation algorithms are designed based on the ideal assumption where the antenna arrays are free from imperfect conditions. But in practical situation, ideal conditions are extremely difficult to obtain and thus due to imperfect conditions, the performance of DOA estimation will be severely degraded. Results of classical methods like MUSIC or Beamforming for direction of arrival estimation degraded when sources are close or coherent or having low SNR. Based on the investigation to classical DOA algorithm (MUSIC and Improved MUSIC), a mod-MUSIC estimation algorithm is proposed which makes full use of signal subspace and noise subspace characteristics. It has good performance in imperfect condition and compare this algorithm with classical algorithms in different conditions.

Keywords: DOA estimation; Array signal processing; Eigen space; Eigen vector