Research On Key Technology Of High Speed Communication Based Aeroplane Power Line

In this paper, the key technology of PLC (Power Line Communication) for the airborne e1ectromechanical communication system is studied, which has great economic value to accelerate the modernization of aeronautic equipments in our army. The paper introduces the research and recent development of low-voltage power line communication technology, which is used widely in commercial area. After analyzing the characteristics of power supply network in aeroplane, a theoretical model for transfer function is established based on the principles of parameters of power line cables in high frequency. The result of simulation by the software Matlab shows that signal attenuation and phasic excursion in high frequency is feasible for high speed communication over power networks in aeroplane. The factors which cause electromagnetic compatibility problems in power line communication are also investigated in detail, and the method to minish the EMC effects is also researched. Based on the DSP, the physical circuit, which mainly contains signal coupling circuit, A/D and D/A circuit, asynchronous communication circuit, is designed. The software related is also designed based on the circuit. The modulation achieved by software is QPSK, which is extensively used in PLC. The circuit and PCB of the PLC modem is designed by EDA software Protel Dxp.Software related such as QPSK,A/D,RS232,is designed.Some parts of the circuit is debugged. The summary and prospect of the research is given finally.