Design Of CubeSat UHF/VHF Transceiver

With the development of space technology,the CubeSat has gradually become a research hotspots in space institutes and some universities due to its advantages of low development threshold,short development period and the flexible launch.The communication subsystem is an important part of the satellite and the only link between satellite and earth.Its importance is self-evident.At present,the research on UV transceiver in China is still in its infancy.The design and development of UV transceiver is of great significance to the development of China's micro-nano satellite technology and even the promotion of commercial space.This paper firstly detailed the overall scheme of the transceiver.Including RF performance indicators,satellite data communication protocol,on-board data communication protocol and transceiver electrical connection scheme.In order to demonstrate the feasibility of the theory of satellite communication,the link margin budget was completed according to the RF performance indicators.Secondly,the transceiver circuit design is completed.The RF receiver is completed with high-sensitivity RF IC.The transmitter uses a discrete module to implement BPSK modulation,and designs a minimum system,high dynamic input power supply circuit and state detection circuit.At the same time,according to the running characteristics of the transceiver,the appropriate embedded operating system is installed,and the software operation framework and software interface response scheme are designed,and the program structure is re-arranged.In order to improve the reliability of the transceiver,the transceiver supports redundant design such as main program switching and online upgrade,and adopts dual-mode dual backup and I2C anti-deadlock design in hardware.Finally,the desktop system test and wireless docking test were carried out,the performance of radio frequency and software on the communication transceiver were evaluated.The results show that the performance of the communicator meets the requirements of the design index,and the conditions for on-orbit verification will be obtained after the assessment of the space environment adaptability.