Fundamentals of Satellite-Maritime Communications: Downlink and Uplink Analysis

Abstract

The imperative of facilitating information transmission to maritime entities situated at substantial distances from terrestrial coastlines presents a critical challenge. Low Earth Orbit (LEO) satellite deployment represents a viable and efficient communication strategy with these geographically remote maritime users. In this paper, we investigate the coverage of satellite-maritime networks in the context of downlink and uplink modalities, where LEO satellites and maritime users are conceptualized as two Poisson point processes at disparate altitudes. According to the directional antenna pattern, the satellite’s serving area is segmented into main and side lobe serving areas. This delineation facilitates a comprehensive analysis of serving distance distributions, probabilities of different interference cases, and maritime user’s connectivity probability. With the evaporation ducting phenomena in satellite-maritime communications, we consider Rician distributed small-scale fading in downlink and line-of-sight (LoS) path in uplink. Furthermore, we derive the distributions of aggregated interference with uplink power control, culminating in distinct coverage probabilities (CPs) for downlink and uplink communications. Moreover, we introduce effective coverage probability (ECP) obtained by multiplying user’s connectivity probability and conditional coverage probability. Extensive simulations verify the theoretical results. Our results elucidate the existence of an optimal satellite altitude and serving angle to maximize ECP in downlink and uplink satellite-maritime communications, respectively.