Reliability of Small Satellite Networks with Software-Defined Radio and Enhanced Multiple Access Protocol

Abstract

Space missions exploiting small satellite networks with a use of software-defined radio (SDR) and advanced random access (RA) protocols have attracted an increased amount of attentions given their low costs, low latency levels, low complexity, and yet competitive data rates for global network services. In this paper, we derive a mathematical model to demonstrate the reliability of a small satellite network with respect to SDR structures, the transmitted signal power on the uplink/downlink channels, code rates, and packet collisions through an enhanced RA protocol. Our model provides quantitative network reliability with respect to SDR system failure rates, feasible communication parameters and packet loss ratios (PLRs). Our analysis suggests a methodology to evaluate network reliability differences according to changes of communication parameters, and a guideline to sustain a reliable network system with appropriate parameter values. We find out that a robust SDR structure with a state-of-the-art analog-to-digital converter (ADC) can provide reliable network services effectively with reduced power consumption, even with high packet traffic loads, to meet operator-required reliability levels for small satellite networks.