基于DSP的LFMCW雷达信号处理技术研究

调频连续波(FMCW)雷达在目标测量系统中有着广泛的应用,而雷达信号的处理是决定测量精确度的关键。本研究设计了一款基于DSP的线性调频连续波(LFMCW)雷达信号处理系统,采用经过三角波调制的 LFMCW雷达信号作为发射信号,来实现目标距离及速度的测量。介绍了 LFMCW雷达的基本结构,分析了实现目标测量的原理,解决了在信号处理过程中,仅采用快速傅里叶变换(FFT)算法而存在的频率分辨率与计算时间的矛盾,提高系统的测量效率。重点研究了雷达信号处理系统的处理算法———FFT 和线性调频 Z 变换(CZT)的联合算法(FFT/CZT 联合算法),同时对 FFT/CZT联合算法也进行了 MATLAB仿真分析。分析结果表明,FFT/CZT联合算法可以显著地提高雷达信号处理的效率和精度。

Research on LFMCW radar signal processing technology based on DSP

Frequency modulated continuous wave (FMCW)radar is widely used in target measurement system,and the radar signal processing is the key to determine the accuracy of measurement.In this paper, a linear frequency modulation continuous wave (LFMCW)radar signal processing system based on DSP is designed to measure the target distance and realtive speed.And the system uses triangle wave modulation of linear frequency modulation continuous wave radar signal as transmitted signal.The basic structure and principle of LFMCW radar are discnssed in order to solve the only using fast Fourier transform (FFT)algorithm and the contradiction between the frequency resolution and the calculation time,improve the measurement efficiency of system,focuses on the signal processing algorithms of the radar signal processing system-FFT and Chirp-Z transform(CZT)of the joint algorithm (FFT/CZT algorithm)to achieve,and analyzed the FFT/CZT algorithm by MATLAB simulation at the same time.The analysis results show that the FFT/CZT algorithm can significantly improve the efficiency and precision of the radar signal processing.