Survey of Inter-Satellite Communication for Small Satellite Systems: Physical Layer to Network Layer View

Small satellite systems enable a whole new class of missions for navigation, communications, remote sensing, and scientific research for both civilian and military purposes. As individual spacecraft are limited by the size, mass, and power constraints, mass-produced small satellites in large constellations or clusters could be useful in many science missions such as gravity mapping, tracking of forest fires, finding water resources, etc. The proliferation of small satellites will enable a better understanding of the near-Earth environment and provide an efficient and economical means to access the space through the use of multi-satellite solution. Constellation of satellites provide improved spatial and temporal resolution of the target. Small satellite constellations contribute innovative applications by replacing a single asset with several very capable spacecraft, which opens the door to new applications. Future space missions are envisioned to become more complex and operate farther from Earth, and will need to support autonomous operations with minimal human intervention. With increasing levels of autonomy, there will be a need for remote communication networks to enable communication between spacecraft. These space-based networks will need to configure and maintain dynamic routes, manage intermediate nodes, and reconfigure themselves to achieve mission objectives. Hence, inter-satellite communication is a key aspect when satellites fly in formation. In this survey, we present the various research being conducted in the small satellite community for implementing inter-satellite communications based on the open system interconnection (OSI) model. This survey also reviews the various design parameters applicable to the first three layers of the OSI model, i.e., physical, data link, and network layer. Based on the survey, we also present a comprehensive list of design parameters useful for achieving inter-satellite communications for multiple small satellite missions. Specific topics include proposed solutions for some of the challenges faced by small satellite systems, enabling operations using a network of small satellites, and some examples of small satellite missions involving formation flying aspects.