NULL BROADENING ADAPTIVE BEAMFORMING BASED ON POLARISATION COVARIANCE MATRIX RECONSTRUCTION

The rapid movement of global navigation satellite system (GNSS) receiver is responsible for the interference steering vector mismatch, which degrades the performance of traditional polarization domain beamforming algorithm. In order to address this problem, a new beamforming algorithm based on polarization domain covariance matrix reconstruction is proposed in this paper, which can broaden the interference null. First, the algorithm analyses the relationship between the interference power and the eigenvalue of the simple covariance matrix, which obtains a simple method to estimate the interference power. Then, we can utilize the interference prior information to construct the steering vector correlation matrix. Therefore, the interference-plus-noise covariance matrix is reconstructed by the correlation matrix and the estimated interference power. Finally, the effectiveness of the algorithm is verified by numerical simulations. Simulation results show that this algorithm can effectively avoid the performance degradation caused by interference steering vector mismatch, which has better robustness than traditional polarization domain beamforming algorithm, and it is able to provide similar signal-to-interference-plus-noise ratio (SINR) close to the optimal value in case of GNSS receiver moving fast.