Relay platform for communicating telemetry data from one or more moving observation satellite(s) to the ground

A communication relay platform of a space observation system, configured to be installed on board an aircraft moving above the clouds, and configured to act as a high-altitude relay for transmitting space observation data, referred to as telemetry data, at a high throughput, between at least one non-geostationary moving observation satellite and at least one target ground station for receiving said data, the transmission from the observation satellite or satellites to the high-altitude relay being capable of taking place during one or more predetermined visibility windows when the moving observation satellite or satellites is visible to the aircraft, and the transmission of data from the aircraft to the ground being capable of taking place constantly,

• the relay platform comprising:
• a first receiving antenna, configured to receive, in a first optical or radio frequency band, observation data transmitted over a first wireless space downlink linking at least one moving observation satellite to the relay platform, and
• a first reception interface, connected to the first receiving antenna and configured to demodulate the data received by the first antenna and save it in a memory, and
• a second transmission interface, configured to modulate the observation data stored in the memory, and transmit said modulated data in a second radio frequency band via a second transmission antenna over a second wireless aerial downlink directly linking the relay platform to at least one target ground station, and
• the relay platform being wherein it comprises:
• a first descending two-level decryption/encryption chain for the telemetry data returned from at least one moving observation satellite to the target ground station or stations.