CubeSat ISR Constellation Mission Tailoring

This paper presents a modelling framework for Intelligence, Surveillance & Reconnaissance (ISR) CubeSat constellation combining optical payload and Software Defined Radio (SDR). The concept satellite is 8-16U depending on the payload resolution and presence of warm-gas propulsion allowing for orbital changes and station keeping extending the operational time. Deployed in 500-km Sun-Synchronous Orbit (SSO), the system targets various mission profiles including ground target surveillance, maritime awareness, disaster response and space object tracking.

Evaluations use 30 deg deflection from the nadir pointing for ground imaging and 15 deg elevation SDR thresholds, incorporating realistic orbital transfer vehicle (OTV) deployment for idealized displacement and propulsion for station-keeping, collision-avoidance, injection phasing and end-of-life deorbit to counter drag. Single satellite benchmarks establish 5-day ground track repeats with dual day/night camera passes for change detection (crop health, target movement, mining) and about approximately 15 minutes of SDR observation per day for spectrum mapping.

Multi-satellite scenarios are optimized for revisit time, aiming to minimize the number of required satellites while maintaining the information domain dominance. Camera coverage achieves 12-hour windows with 5 satellites for diurnal tracking (e.g., shipping routes, border flows) and 6-hour with 10 satellites for intra-day events (e.g., convoys, wildfires). SDR configurations deliver 3-hour gaps via 4 satellites for broad awareness (e.g., interference detection) and 1-hour with 13 satellites for tactical bursts, all with global fallback despite diminishing returns on scaling.

With the today’s market offering about 10-14 months from order-to-launch and vertical integration from level 0 data to fully evaluated outputs shows CubeSats hold a solid stake at the future of constellations.