A new antenna array architecture with hybrid beamforming for broadband satellite communications

In this paper, an antenna array architecture for broadband space communications with overlapped square subarrays is proposed. Analog and digital beamforming are performed consecutively at subarray level and across all subarrays. Subarrays are considered at digital beamforming level as large radiating elements, and thus the spacing between adjacent subarrays is not sufficient to prevent from interference. This leads to the creation of grating lobes. Overlapping methodologies have been studied in the literature and is an effective solution to mitigate this non-desired grating lobes. An overlapping strategy is proposed in this paper and can be seen as a shift by half the size of a subarray along 2-D. This enables a total mitigation of odd grating lobes. A comparison is made to benchmark this architecture performance compared to other existing strategies.