Decentralised Satellite Infrastructure

Over the past decade we have witnessed a paradigm shift in the commercialisation of space with a vast array of companies entering the space industry. It is now possible to find service providers for every stage of a space mission, from chip designers and microsatellite vendors to launch providers and ground stations services. Companies from all over the globe are now ready to service space missions. However, the way each mission is designed and executed has not seen the same transformation. Most missions are still single vendor, single purpose, and not networked to other spacecraft, resulting in an inefficient allocation of resources. To get to the next stage of the space industry spacecraft need to have the ability to network together to create collaborative satellite constellations, but there are some technical challenges:

• A platform-based environment needs to be constructed with trust among various participating parties.
• Communication among satellites needs to follow a unified standard to enable a flexible and efficient information routing.

SpaceChain Foundation aims to target these challenges, building an alliance consortium towards the creation of a Decentralised Satellite Infrastructure (DSI), a mesh-network of heterogeneous spacecraft owned and operated in Low Earth Orbit (LEO) by multiple parties in multiple jurisdictions. Spacecraft may join or depart the constellation at any time via a blockchain registry, as long as the crafts meet minimal economic, technical and regulatory requirements sufficient to ensure the long term health and resilience of the constellation.

Blockchain Registry of DSI

Blockchain technology supports the backbone of the DSI architecture via a Blockchain Registry. During the registry phase a satellite would certify that it met the minimum operational standards to be added to the network. Once approved the satellite would be assigned a private key and the ability to route and allocate DSI assignments via a smart-contract based blockchain bidding environment, ensuring transparency and trust.

Satellite Mesh-network Routing

With DSI, participating satellites will be able to support secure information transmission between distant parties, served as relays via a new Optical Link routing protocol. The routing protocol development focuses on how relay nodes are chosen for efficient information transmission between two distant satellites, as well as how a robust relay network could be established for the entire DSI network.

Current inter-satellite communication is based mostly on RF signals. RF transmission requires a simple hardware setup but offers slow data transmission rates. Optical links, on the other hand, provide high communication speed but also require complicated hardware including source APT (acquisition, pointing and tracking) systems and detection modules. However, for long distance communication in space, optical links have outstanding performance compared with RF, making it a necessary component for future development of satellite technology. Thus, we aim to develop an effective optical inter-satellite link model which is easy for adaptation to a traditional satellite company.

Hardware and Software Standards

SpaceChain Foundation will collaborate with partners and manufacturers to enable satellites to participate in DSI freely by developing standards related to:

• Processing power: Minimum processing requirements will be applied to the participating satellites to enable activities under the Blockchain registry, smart contract ‘bidding’, mesh-network support and routing protocol for the DSI.
• Data storage and encryption: Minimum storage capacity will be established for storing and synchronising DSI assignments, as well as uniform encryption standards.
• Optical link bandwidth and APT systems: Minimum bandwidth for optical links and minimum hardware for APT systems will be established to maintain robust connectivity and throughput.

To enable high-speed communication, DSI would introduce optical communication links between participating satellites in addition to traditional RF communication, supported by an acquisition, pointing and tracking (APT) system. Mesh-network and routing protocols would support valid communication between satellites with RF and optical links via certain relay nodes.

Collaboration with Geosynchronous Satellites and Deep Space Research

Interoperability with geosynchronous satellites (GEO) as well as external constellations is one of the core development focuses for DSI. Although the majority of DSI satellites will be participating members of the LEO mesh-network, connections with GEO satellites and other unaffiliated external constellations would make a more robust network, as well as providing a relay for spacecraft operating in High Earth orbit or deep space.

With improved communication speed among various nodes, DSI satellites could serve as receivers for information transmitted back from satellites in deep space. A potential collaboration could be established by sending deep space exploration satellites with optical communication modules, sending back information to DSI satellites or relay the information from other deep-space satellites received by its RF module.