| Summary: | 碩士 === 國立中央大學 === 光機電工程研究所 === 102 === 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.
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