Research On Ground Information Launch Technology Of Aircraft Safety Control System

The safety control system is vital to all aircraft with safety hazards.It is directly related to the safety of surrounding personnel and huge property losses.The aircraft safety control system mostly uses the traditional PCM/PSK/FM information transmission technology,but with the continuous improvement of the level of science and technology,the traditional technology faces some challenges.The new high alphabet modulation proposed by NASA has been widely studied at home and abroad due to its good real-time performance and high reliability,and is applied to aircraft safety control systems.This paper introduces the ground launching platform of aircraft safety control system consisting of industrial computer and security control card.The industrial computer is used to realize human-computer interaction.The security control card includes the bridge chip PCI9054,remote control transmitter and closed loop detection loop for the transmission and closed-loop detection of security control information.This paper mainly studies two information transmission technologies,PCM/PSK/FM and high alphabet modulation,and completes the transmission and closed-loop detection of security control information through the ground launching platform.The closed-loop detection is used to verify the launch completion status of the security control information.According to the needs,this paper firstly designs the human-computer interaction interface of the ground launching platform,and realizes it through the MFC architecture of VC++6.0 development environment;secondly,in the FPGA development environment Quartus Ⅱ 9.0,through the Verilog HDL hardware description language,the FPGA design of PCM/DPSK/FM and high alphabet modulation information transmission technology and detection loop are realized respectively,including DPSK modulation and demodulation,and high alphabet modulation and detection demodulation;again,based on the functional simulation software Modelsim,the FPGA design content is verified by simulation;finally,the whole machine test is carried out on the ground launching platform of aircraft safety control system.The experimental results show that the security control information realizes the transmission and closed-loop detection under the two kinds of information transmission technologies of PCM/DPSK/FM and high alphabet modulation through the ground launching platform,and reaches the RF frequency of 1.75GHz～1.85GHz and the FM frequency offset of 24KHz,and completes the whole machine test.The theoretical analysis of performance shows that the high alphabet system designed by this paper makes the virtual command rate of safety control system reach the order of 10-54,and the leakage command rate reaches the order of 10-20(15dB signal-to-noise ratio),which is better than the PCM/DPSK/FM system under the same conditions,and more in line with the reliability and security requirements of the safety control system.