Space mission resilience with inter-satellite networking

Abstract Satellites typically operate in isolation from their orbiting counterparts, but communicating only with ground-based infrastructure leaves them susceptible to the consequences of on-board anomalies. Loss of payload, communication system, or other sub-system function could render the entire satellite inoperable. This susceptibility can be partially mitigated through the addition of an inter-satellite networking capability, which offers value in terms of increased general performance and an increased resilience to on-board anomalies. While a typical platform can be modelled to exhibit only two fundamental states: operational and failed, a networking-capable platform (specifically one with an inter-satellite communication capability) exhibits six states, each reached through a unique combination of sub-system malfunctions. The result of this added resilience is a reduction in the likelihood of the satellite reaching a fully-failed state. Simulations for independent and networking-capable systems are presented that illustrate the benefits and limitations of inter-satellite networking in terms of failure resilience. It is shown that whilst a networked system can be expected to reach greater levels of performance utility, sub-system anomalies are found to result in greater percentage levels of performance degradation compared to a non-networking-capable system with similar characteristics.