An implementation of MIMO InSAR without transmitting orthogonal signals

The ability of MIMO InSAR to reconstruct the terrain height profile would outperform the ordinary multibaseline InSAR. One key of implementing MIMO InSAR is the echo separation on the receiving end. However, the available orthogonal signals would introduce severe cross-interference due to their inadequate orthogonality for imaging. A feasible implementation of MIMO InSAR is presented in this paper, in which the antennas of MIMO InSAR would emit signals alternately in different pulse repetition intervals. Thus, the mainlobe echoes of signals transmitted by different antennas would return in different pulse repetition intervals coordinately, which implies the cross-interference could be suppressed sufficiently even with non-orthogonal transmitting signals as long as a low-sidelobe antenna is employed. The performance of the proposed implementation is proved via numerical simulations.