Analysis of GEO Satellite Relay Coded Systems

The recent development of the low Earth orbit (LEO) satellite constellation construction has accelerated the research on applications associated with LEO satellites. One such typical application is to transmit high-resolution remote-sensing images from LEO satellites to ground stations (GS). However, the stringent visible time and the complicated antenna manipulation between LEO satellites and GS makes it challenging for a LEO satellite to complete its full transmission mission within a specified stringent deadline. As such, this paper introduces a geosynchronous equatorial orbit (GEO) satellite as a relay and explores the distributed coding-decoding schemes to assist reliable and high-speed transmission. Specifically, four types of GEO-satellite-relay coded schemes are proposed and analyzed, including three PHY-only coding systems with GEO-full-decoding on board, decoding on ground only, and GEO-partial-decoding on board and one layered coding system. Through simulations, the comparative insights among the four schemes are provided from three dimensions: effectiveness, reliability, and relay complexity. The trade-offs concerning the four schemes in terms of the three indexes are also revealed.