K-/Ka-Band Shared-Aperture Integrated Phased Array for Satellite Ground Terminals

This article presents a 256-element shared-aperture integrated phased array for K-/Ka-band satellite communication (SATCOM). It supports two orthogonal circular polarizations (CPs) in both bands. The transmitting (TX) and receiving (RX) antenna elements are interleaved in a single planar aperture, achieving a compact configuration while avoiding the insurgence of grating lobes. The filtering-antenna technology is introduced in antenna element design, leading to more than 35-dB isolation between the TX and RX elements. The array is based on separate sets of TX and RX beamforming (BF) ICs to realize independent BF capabilities. Fabricated in the multilayer print circuit board (PCB) technology, the shared-aperture integrated phased array can scan up to ±60° of both TX and RX beams. The equivalent isotropic radiated power (EIRP) achieves 61.5 dBm, and the maximum G/T is −0.55 dB/K.