經實驗驗證本轉發網路之分散式架構能有效增加地面站收訊覆蓋面積,採用之雙通道架構於1 Hz 76.8kbps發送下PER (Packet Error Rate)為1%,相較於單頻轉發方式之PER降低0.97%,而RPR (Repeated Packet Ratio)降低38.4% 在純電池供應操作環境可待機達30小時,日照充足則可提供不中斷連續待命,於酬載資料brust下鏈時最大可提供11小時連續工作時間。 ;This thesis focuses on the micro-satellites, sounding payload and other long-distance radio communications requirements, using dual-band transponders as nodes to construct a low-attitude radio reception network.
The radio reception network uses COTS (Commercial Off-The-Shelf) components to constitute a digital Communication systems operating in ISM band (Industrial, Science, Medical) which using MSK modulation (Minimum Shift Keying), 2.4 ~ 250 Kbps transfer rate with CRC (Cyclic Redundancy Check). System working in dual-band half-duplex transponding, each node in the network are equipped with GPS and battery SOC, ground station can real time monitor the position and power status of transponders. Transponding protocols using our special algorithms and topologies, which can reduce the possibility of echo caused by repeated transponding. Transponder network monitoring console of Ground station is programmed by C # with GoogleMap API and Java Script.
The experimental verification of the radio reception network can effectively increase the ground station reception coverage. The PER (Packet Error Rate) of dual-band transponder architecture at 1 Hz 76.8kbps is 1% . Compared to single band transponder architecture, the PER reduced 0.97%, and the RPR (Repeated Packet Ratio) improved 38.4%. In standby state, lifespan of battery up to 30 hours, abundant sunshine can provide uninterrupted continuous standby. Maximum available continuous operation time of payload data downloading (without sunshine) up to 11 hours.