基于交错算法的FMICW技术在车载雷达中的应用

Application of FMICW technology based on stagger algorithm in automotive radar

调频中断连续波(FMICW)雷达收发转换开关频率满足一定约束条件时,不仅保留了调频连续波(FMCW)雷达峰值功率低、距离分辨率高、对其他系统干扰小等优点,而且解决了发射机能量泄露导致接收机过载的缺点。所提方案研究FMICW技术由于收发过程的不连续性,在车载雷达中采用单一开关频率的传统方法会出现多个杂散频谱尖峰的问题。使用带通滤波器消除杂散尖峰的精度取决于对目标距离的先验估计,使用伪随机中断序列的方法会使本底噪声的平均功率增大,动态检测范围缩小。所提方案使用了一种基于多个开关频率的交错算法,在多个频谱上每个频率位置做最小化可在频域中直接消除杂散尖峰。经实验分析,FMICW应用在车载中与等效FMCW雷达检测性能接近,且对多目标环境具有良好的适应性。

The problem of spurious spectral peaks produced by the traditional method of using a single switching frequency in automotive FMICW radar was focused by the proposed scheme. The system accuracy depended on the previously estimated range if a bandpass filter was utilized to eliminate the spurious spectral peaks, and the noise floor could be too high to achieve the required dynamic detection range if the random interrupted sequence method was utilized. A stagger algorithm based on multiple switching frequencies was used, in which the spurious peaks from the frequency domain could be removed by minimizing each frequency position on multiple spectrums. Simulation results show that the proposed method is close to the equivalent FMCW radar detection performance, and is good in multiple targets scenario.