Intersatellite links: Requirements for future missions and limitations from spacecraft resources

Intersatellite links (ISL) added to existing systems for benefits in communication range, capacity coverage, connectivity, and synchronization are indicated. System costs in terms of requirements on the spacecraft and development risks are discussed. For a deep space mission, long geo-arc and cluster communication ISL link budgets are analyzed, comparing microwaves and laser links. Mass, power, volume requirements and critical developments are examined, particularly growth potential. It is concluded that microwave and optical ISL's have complementary roles and require specific optimization.