Abstract: This paper proposes a new DOA (direction-of-arrival) estimation in low-angle tracking environment. For the MIMO radar, not only received multipath signals but also transmitted multipath signals should be considered due to the multipath effect. The proposed algorithm applies a double port signal processing to receivers and transmitters based on the improved Maximum Likelihood method which only needs one dimension search on space. This process can extend the array aperture respect to the case of single port array signal processing. Hence the new algorithm improves the resolution and accuracy of DOA estimation of the elevation at a low SNR and has low computational complexity.

Key words: MIMO Radar, multipath effect, low-angle tracking, Maximum Likelihood