Unconventional beamforming for quasi-hemispheric coverage of a phased array antenna

It is usually difficult to synthesize a wide-angle coverage beam for an array antenna. In this letter, we propose an unconventional beamforming approach for a phased array antenna. By optimizing the orientations and depths of nulls of the radiation pattern, 'effective' quasi-hemispheric coverage with a single remaining null in the direction of no interest can be achieved. We modify an existing nulling algorithm to synthesize such a special radiation pattern by introducing a hypothetical incidence of interference and Gaussian white noise. Analysis and simulation of a five-element linear array antenna verified the effectiveness of the proposed approach.