Passive Metasurface-Based Low Earth Orbit Ground Station Design

Abstract

Low Earth Orbit (LEO) satellite communication is vital for wireless systems. The main challenges in designing LEO satellite ground stations include increasing the input signal strength to counteract severe path loss, and adaptively steering the direction of the output signal to accommodate the continuous movement of LEO satellites. To overcome these challenges, we present a novel transceiver system, referred to as MetaLEO. This system integrates a passive metasurface with a small phased array, enabling powerful focusing and adaptive signal steering. By harnessing the metasurface's robust wavefront manipulation capabilities and the programmability of phased arrays, MetaLEO offers an efficient and cost-effective solution that supports both uplink and downlink bands. Specifically, we devise a joint optimization model specifically to obtain the optimal uplink codebook for phased array antennas and metasurface phase profile, which enables electronic steering. In a similar manner, we establish the downlink metasurface phase profile to enhance focusing and signal reception. MetaLEO's efficacy is evaluated via theoretical analysis, simulations, and experiments. Our prototype includes a single metasurface with 21×21 uplink and 22×22 downlink elements, and a 1×4 antenna array for receiving and transmitting. Experimental results show signal strength improvements of 8.32 dB (uplink) and 16.57 dB (downlink).