Robust beamformer design by power minimization and its unconstrained partitioned implementation

A robust array beamformer design method by power minimization and its unconstrained partition implementation is proposed in this paper. An orthogonal blocking matrix is obtained through the proposed method. The new blocking matrix ensures that a desired look-direction response of the processor over a frequency band of interest can be closely approximated. Furthermore, if the spectrum of the target signal is known a priori, such as in microphone array application where the statistical property of speech is known, the new method may use fewer/less degree of freedom. This new method also provide a theoretical support for the derivation of the blocking matrix through array calibration. Simulation results show that the effectiveness of the proposed method.