Reduction of complexity for digital beamforming in high-altitude-platform and satellite systems

In this paper, we propose a new digital beam-forming scheme for high-altitude-platform (HAP) and satellite systems. In the proposed scheme, the number of antenna elements and the corresponding receiver modules, analog to digital (A/D) converters etc., can significantly be reduced without loss of performance. As a result, the system complexity and system costs can be reduced. Furthermore, in the proposed scheme, it allows to specify narrow main beamwidth and low sidelobe level simultaneously. Illustrative design examples and beam-pattern comparisons with traditional digital beamforming scheme are included.