Enhancing Joint Communications and Sensing for CubeSat Networks in the Terahertz Band through Orbital Angular Momentum

This work presents the first space-borne joint communication and sensing (JCS) platform, capable of performing atmospheric humidity sensing while simultaneously transmitting to a Ground Station receiver. Atmospheric sensing is performed through the Differential Absorption Radar approach, which requires transmission at high frequency/high absorption peaks (183 GHz). These frequency requirements are met thanks to the use of state-of-the-art sub-terahertz (THz) frontends, which are also leveraged by the communication system. The proposed design also leverages the latest advancements in wavefront engineering and uses a passive deployeable intelligent reflecting surface (IRS) on board of the satellite to simultaneously combine the communication signals with the sensing signals without interference (orthogonal mode multiplexing). The resulting sytem design performance is evaluated through simulation, achieving up to 400 Gbps and 160 Gbps for output powers of 3 W and 500 mW, respectively.