Adaptive Beamforming Technique for Virtual Antenna Using Modified Interpolated Spatial Smoothing Algorithm

In this paper we present an effective algorithm to inhibit the coherent interference with the virtual antenna based on the traditional interpolated spatial smoothing algorithm. Using the interference subspace projection concept, we establish an interference space utilizing the virtual array interfere steering vectors and then project the transformation matrix to it. The theoretical analysis has demonstrated that the interference components in the virtual covariance matrix can be enhanced. Then by employing the minimum variance distortionless response (MVDR) beam forming method, it can improve the robustness of adaptive beamforming with virtual antenna array, and significantly enlarge the inhibition gains on the coherent interference and output signal to interference and noise ratio (SINR).