Abstract:The new low-cost observe and control system of multi-aircraft cooperative Unmanned Aerial Vehicle(UAV) is designed. The Time Division Duplex(TDD) protocol is adopted to resolve the problem that half-duplex communication is transformed to full-duplex communication between data radios at zero cost, then it can realize the application of single carrier full-duplex control mode based on data radio. This system adapts to the development trend of miniaturization and low-cost for observe and control system. The communication mode of time-division multiple address based on heartbeat is designed to reduce the synchronization error. It can resolve the problem that telemetry data is blocked up in the same frequency channel for many flights, and create favorable conditions for multi task control on the same screen for multi-aircraft cooperative UAV.