Abstract：A robust quaternion-valued wideband adaptive beamformer is proposed, in which a quaternion is utilized to arrange the output of the array element. By exploiting the augmented envelope alignment technique, adopting the three involutions of quaternion, and incorporating the noncircular information of the signal simultaneously, a quaternion-valued wideband augmented signal model is established to achieve the robust adaptive beamforming based on signal subspace projection. Compared with other wideband beamformers, the proposed scheme exhibits a better performance in extracting noncircular signals by array aperture extension, and is insensitive to the pointing error. The simulation results verify the efficiency of the proposed beamformer.
