Beam steering limitations in hardware-combined phased arrays for LEO satellite communications

Abstract Low Earth orbit (LEO) satellite constellations are emerging as a key enabler of global connectivity, addressing the broadband needs of remote and underserved regions with high-speed and low-latency services. These satellite backhaul links are expected to play a crucial role in the integration and expansion of future 6G networks. Phased array antennas, essential for agile beam steering and continuous satellite tracking, are often implemented with many elements but without a dedicated digital receiver per antenna. Instead, signals are combined in hardware to reduce system cost and complexity. This paper presents an analytical evaluation of the beam steering performance of such analog-combined arrays. The analysis reveals performance degradation and limitations in the beampattern compared with fully digital arrays. Simulation results support the analytical model and quantify the impact of reduced digital reception on array performance.