Design of a Spaceborne Earth-Coverage Scanning Phased Array Antenna Based on Mirror Beamforming Networks for MEO Satellite Communications

This paper proposes a spaceborne Earth-coverage scanning phased array (ECSPA) antenna based on shared subarray architecture for medium Earth orbit (MEO) satellite communications. A couple of mirror beamforming networks are utilized for shared subarray to obtain the Earth-coverage beam of MEO satellites in two symmetrical sections by mirror imaging, effectively reducing the optimization difficulty. An ECSPA consisting of 40 shared subarrays based on the mirror beamforming networks has been designed and analyzed. Numerical results indicate that the scanning gain variation of the ECSPA can well match the space loss variation during beam scanning, and adaptively compensate for the path loss variation between the satellite and ground users at different locations, demonstrating excellent Earth-coverage scanning characteristics. Additionally, the ECSPA exhibits grating lobe suppression, further improving the anti-interference performance of the satellite system.