某无线电近程导航系统机载设备信号处理与仿真研究

Research on Signal Processing and Simulation of Radio Short-Range Navigation System Airborne Equipment

针对某无线电近程导航系统机载设备的基带与中频信号进行了仿真研究。主要借助Matlab生成基带信号并通过幅度调制产生中频信号,使用Simulink频谱分析仪的Channel Measurement工具计算出中频信号的带宽,参考该带宽参数设计了中频信号解调模块,使用带通滤波、相干解调和低通滤波等方式无失真的将中频信号解调出来,并基于可编程逻辑器件(FPGA)内建随机存取存储器(RAM)实现了发射基带脉冲生成。通过以上过程完整正确地验证了信号调制和解调方法。

The signal processing and simulation on the baseband and Intermediate Frequency(IF) signals of the airborne equipment of the radio short-range navigation system are proposed.The baseband pulse signal is generated mainly by Matlab software and the IF signal is generated through amplitude modulation.The bandwidth of the IF signal is calculated using the Channel Measurement tool of the Simulink spectrum analyzer.Based on the bandwidth parameter,an IF signal demodulation module is designed.The demodulation of the received pulse signal is achieved through band-pass filtering,coherent demodulation,and low-pass filtering.The transmission baseband pulse generation is realized based on the built-in Random Access Memory(RAM) of the Field Programmable Gate Array(FPGA).The signal modulation and demodulation methods are verified completely and correctly through the above processes.