基于声波的飞机DME测距系统模拟设计与实现

Simulation design and implementation of aircraft DME ranging system based on acoustic wave

摘要:

飞机DME测距仪体积重量过大、电路复杂，为了简化结构和实验教学，设计了一种基于声波的DME测距系统。该系统采用音频应答式测距的方法，以现场可编程门阵列（FPGA）为核心处理器，处理和解析信号，完成询问码脉冲鉴别、产生静默时间、进行识别码等功能，使用滤波器对声波信号进行数字滤波。实验结果表明:整个测距系统询问-应答过程工作完整，实现了模拟DME的测距功能，精度在毫米范围内，系统稳定性好，具有小巧便捷、高精度、性价比高等优势，利用本设计学生可动手操作测距仪，更加直观地感受传播应答过程。

Abstract:

The volume and weight of aircraft DME range finder are too large and the circuit is complex. In order to simplify the structure and experimental teaching, a DME ranging system based on acoustic wave is designed. The system adopts the method of audio response ranging, takes field programmable gate array ( FPGA ) as the core processor, processes and analyzes the signal, completes the functions of query code pulse identification, silent time generation, identification code and so on, and uses the filter to digitally filter the acoustic signal. The experimental results show that the inquiry-response process of the entire ranging system is complete, and the ranging function of the simulated DME is realized. The accuracy is within the millimeter range, and the system has good stability. It has the advantages of small and convenient, high precision, and high cost performance. Using this design students can operate the range finder, more intuitively feel the propagation and response process.