基于扩频的汽车雷达后向散射通信系统研究

汽车雷达是自动驾驶车辆不可或缺的传感器。随着智能交通技术和车路协同技术的发展，通过后向散射通信技术，为前向防撞雷达增加路旁交通标志的标签识别功能将具有重要的应用价值。本文针对标签后向散射信号能量弱，易受车辆目标回波、杂波和噪声的影响，在传统汽车防撞雷达的基础上提出一种基于扩频编码的调频连续波雷达后向散射通信系统。系统将直接序列扩频技术引入到标签的后向散射调制中，利用接收解扩处理产生的扩频增益增强标签后向散射信号，从而达到标签目标检测和信息提取的目的。仿真结果表明，该系统能够区分车辆和标签目标，准确识别标签信息。扩频编码技术的引入大大降低了系统误码率，提高了系统稳定性和可靠性。

Research on Backscatter Communication System of Automotive Radar Based on Spread Spectrum

Automotive radar is an indispensable sensor for autonomous vehicle. With the development of intelligent transportation and vehicle-road coordination technology, the tag recognition function of roadside traffic signs for forward anti-collision radar through backscatter communication technology will have important application value. The energy of backscatter signal is weak and susceptible to the vehicle echo, clutter and noise. A frequency-modulated continuous wave radar backscatter communication system based on spread spectrum coding is proposed on the basis of traditional automotive anti-collision radar. The direct sequence spread spectrum techno-logy is introduced into the backscatter modulation of the tag in the system. And the backscatter signal of the tag is enhanced by the spread spectrum gain generated by de-spreading, thereby achieving the purpose of tag target detection and information extraction. The simulation results show that the system can distinguish the vehicle and the tag target and identify the tag information accurately. The introduction of spread spectrum technology reduces the system bit error rate greatly and improves stability and reliability of the system.