低轨卫星L频段中继通信载荷技术研究OACSTPCD

To support the real-time high data rates communications between sea and land-based systems,a highly integrated,low-cost and low-power L-band relay communication payload is designed and implemented for low Earth orbit(LEO)satellites.The relay communication payload integrates the communication antenna,radio frequency(RF)front-end,signal processing unit,power conversion unit and interface unit.The receiving front-end is designed with an active phased array antenna,and the transmitting unit is designed with a GaN power amplifier to improve the G/T value of the receiving unit and the effective isotropic radiated power(EIRP)of the transmitting unit.The signal processing unit integrates a zero intermediate frequency(IF)receiving structure and a direct RF modulation structure to complete the functions of receiving and demodulating 8 Mb/s data in the reverse link and processing and forwarding data in the forward link.The space environment simulation experiments in individual and followed with the satellite situations are done and the simulation tests of the communications link between the satellite and the ground systems are finished.The payload on board enables L-band satellite communications.Its mass is 12.87 kg and power consumption in more than 30 W RF power is 91.2 W(3.04 A/30 V)in-25℃～+55℃conditions.