A pulse-train MIMO radar based on theory of independent component analysis

Abstract

The idea of co-located Multiple-Input Multiple-Output (MIMO) radars is based on transmission of orthogonal signals. In conventional co-located MIMO radars, usually a set of orthogonal code modulated pulses is transmitted. In this approach, finding orthogonal signals with a proper range side-lobe level is a problem. In this paper the approach of transmitting a set of proper pulse-trains is proposed. In the pulse-train signaling, pulse compression is achieved by the stepped frequency idea and so, the range side-lobes of the compressed codes are not a problem in the process of code selection anymore. To separate the received pulse trains, a new approach based on the Independent Component Analysis (ICA) is proposed. Compared to other presented approaches which use a set of filter banks, it is shown that the ICA-based approach is less sensitive to the Doppler effect and the orthogonality of signals. So, better beam-forming features and less error in Direction of Arrival (DOA) estimation is gained in this approach. According to this approach, an appropriate signal design method is presented, based on the separation performance of ICA algorithms. It is shown that independent random sequences are proper signals in this sense