Abstract:

Aiming at the problems of poor accuracy, low angular resolution, and low degree of freedom in traditional bistatic nested multiple input multiple output (MIMO) radar for target parameter estimation, a method based on the use of virtual redundant array elements is proposed. The reconstructed Toeplitz matrix algorithm is a method of parameter estimation for the direction of departure (DOD) and direction of arrival (DOA) of the target. Firstly, the two nested sub-arrays are arranged with the zero point as the center to form the receiving array and the transmitting array of the bistatic MIMO radar. The virtual receiving signal processed by the array has a large number of redundant virtual array elements. Secondly, the covariance values corresponding to the redundant virtual array elements are averaged to replace the original values to form a new virtual received signal, and then two selection matrices are used to construct spatial smoothing sub-arrays in the virtual receiving array and the virtual transmitting array. The method reconstructs the Toeplitz matrix to reconstruct the virtual received signal. Finally, the conventional subspace algorithm is used to estimate the space spectrum of the equivalent virtual signal to realize the mutual matching of DOD and DOA. The proposed algorithm compares better with other algorithms in terms of estimation performance and degree of freedom performance.

Key words: redundant virtual element, nested array, bistatic multiple input multiple output (MIMO) radar, joint angle estimation