Design And Implementation Of Micro Low Consumption Data Transmission Communicator

With the rapid evolution of integrated circuits and the digital devices in the information era,the Pico-Nano satellite has been a hotspot in the modern satellite area.The space borne data transmission communicator,as the core components of the Pico-Nano satellite,play an important role in the communication between ground and other satellites.It's developing towards miniaturization,low power consumption and high data transmission speed.Therefore,it has a practical meaning to develop a data transmission communicator which reaches the criterion of Pico-Nano satellite.Aiming at the application requirements,this paper completes the design and research of a data transmission communicator which meets the international standard of "1U" CubeSat based on the current research status,supports higher data transmission as well.The research contributions of this paper are as follows:(1)The hardware design of the data transmission communicator has been completed within the area of 90×70mm2.It refers to the "1U" standard of CubeSat,using direct-up conversion architecture,has a complete transceiver module which is compatible with the TT&C platform.(2)According to the hardware platform,the data transmission system has been realized with the symbol rate of 40Mbps and DQPSK modulation.It also adopts concatenated coding with RS(255,223)and Convolution(7,1/2),brings 7 dB coding gain when the bit error rate is 1 × 10-5.(3)The problem of IQ imbalance in the direct-up conversion communicator and the influence of temperature to the band inhibition degree has been analyzed in detail.In order to realize self-calibration of IQ imbalance between-30? and 70?,this paper designed an IQ self-calibration software program,using FPGA and the calibration module of the RF integrated chip.The LO and image rejection ration can reach-62dBc in actual measurement.(4)By actually testing this miniaturization data transmission communicator through experimental equipment,its symbol rate can be 40Mbps under the power consumption of 4.15W.Meanwhile,its EVM is less than 4.7%,magnitude error is less than 0.25dB and phase error is less than 2.5°,all the performances satisfy the design requirements.In summary,the communicator has the advantages of miniaturization and low power consumption.It can meet the data communication requirements of the micro-satellite because of its higher data transmission speed.It has some reference value for the future design of data transmission communicator.