Multi-User Communication-Assisted Sensing via Direct Satellite-to-Vehicle Communications

In this article, we investigate how to integrate multi-user communication-assisted sensing with direct Low-Earth-Orbit (LEO) satellite-to-vehicle (DS2V) links to achieve high-accuracy situational awareness under strict resource constraints. We first present a precision information delivery framework — determining who, where, and when to transmit — so that only vehicles with relevant sensing needs receive the appropriate data. We then propose a novel content-aware transmission strategy that exploits the partial correlation of sensing requests among vehicles to jointly encode common and private data, thereby reducing redundant transmissions and enhancing spectrum efficiency. Together, these methods enable improved sensing accuracy even in large satellite coverage footprints characterized by high mobility, intermittent handovers, and noticeable Doppler shifts. We also outline how integrated sensing and communication (ISAC) principles can be tailored to the DS2V environment, including joint source-channel coding and task-oriented information exchange for latency-sensitive vehicular applications. Finally, we discuss open research challenges — ranging from advanced interference management to AI-driven beam scheduling and reconfignurable intelligent surfaces — and chart future directions for resilient, scalable, and cost-effective satellite-based vehicular sensing networks.