BALLOON NETWORK WITH FREE-SPACE OPTICAL COMMUNICATION BETWEEN SUPER-NODE BALLOONS AND RF COMMUNICATION BETWEEN SUPER-NODE AND SUB-NODE BALLOONS

Exemplary embodiments may involve hierarchical balloon networks that include both optical and radio frequency links between balloons. An exemplary network system may include: (a) a plurality of super-node balloons, where each super-node balloon comprises a free-space optical communication system for data communications with one or more other super-node balloons and (b) a plurality of sub-node balloons, where each of the sub-node balloons comprises a radio-frequency communication system that is operable for data communications. Further, at least one super-node balloon may further include an RF communication system that is operable to transmit data to at least one sub-node balloon, where the RF communication system of the at least one sub-node balloon is further operable to receive the data transmitted by the at least one super-node balloon and to transmit the received data to at least one ground-based station.