MediSat: A Secure Delay-Tolerant CubeSat Constellation for Medical Data Relay in Infrastructure-Degraded Environments

Reliable transmission of medical data during disasters and in remote regions remains a critical challenge due to damaged, congested, or nonexistent terrestrial communication infrastructure. This paper presents MediSat, a SmallSat-based system concept for secure, delay-tolerant relay of medical data using a constellation of CubeSats operating in low Earth orbit. The proposed architecture employs a store-and-forward networking approach combined with end-to-end encryption, autonomous onboard data handling, and quality-of-service prioritization to enable resilient transmission of time-critical healthcare information between field medical units and centralized healthcare systems.
The system design is developed using a structured systems engineering methodology aligned with ECSS practices and SmallSat constraints, covering mission definition, functional decomposition, subsystem allocation, and interface management. Key technical features include delay-tolerant networking protocols, encrypted data storage and transmission, autonomous scheduling of communication windows, and scalable constellation architecture. Subsystem-level considerations for communications, onboard data handling, power, attitude control, and thermal management are discussed to demonstrate feasibility within CubeSat mass, power, and volume limits.
The paper highlights the applicability of the proposed architecture to disaster response, humanitarian operations, and remote healthcare connectivity, and discusses expected performance, scalability, and verification approaches. MediSat demonstrates how SmallSat constellations can be systematically adapted to support secure, resilient medical communications, extending SmallSat applications beyond conventional Earth observation and Internet-of-Things use cases.