Adaptive beamforming using uniform circular arrays under mutual coupling environments

The problem of adaptive array beamforming using a uniform circular array (UCA) under mutual coupling situation is considered. The well-known robust Capon beamformer (RCB) has been shown to be effective in dealing with many array uncertainties. However, it suffers from the mutual coupling (MC) between array sensors. We present a simple eigenspace-based (ESB) method to effectively mitigate the MC effects. The novelty of the proposed method is that it finds a weight vector which lies in the signal subspace of the data correlation matrix to alleviate the MC effects. Simulation examples show that the proposed method is more robust than the RCB.