Array diagnosis and angle estimation in bistatic MIMO radar under array antenna failures

Abstract

The presence of fault antennas in bistatic multiple-input–multiple-output (MIMO) radar causes a significant degradation of angle estimation performance. In this study, the authors present a signal-processing scheme for bistatic MIMO radar with impaired receive array including array diagnosis as well as angle estimation. The damaged antenna in the receiver, which is incapable of receiving the target signals and leaves only the thermal noise generated within the receiver itself, leads to a decrease in the entropy of its received data. The dissimilarity of the entropy values between the damaged and normal receive antennas is used for array diagnosis. Thereafter, the useless noise data of the detected fault antennas is removed in the receive signal matrix, so that the successive data missing occurs along the row directions of the signal subspace matrix. A low-rank block-Hankel structured matrix is constructed from the incomplete signal subspace matrix, which can facilitate the exploitation of the matrix completion technique to recover that successive missing data. On the basis of the restored rotational invariance structure of the complete signal subspace, the estimation of signal parameters via rotational invariance technique can then be applied for angle estimation. Simulation results confirm the validity of the proposed methods.