面向电磁特性测量的毫米波级联雷达系统设计

Design of Millimeter Wave Cascade Radar System for Electromagnetic Characteristics Measurement

单芯片毫米波雷达面临着测量维度单一、分辨率低的问题,级联雷达芯片可以获取目标的多维信息,但是给信号采集、存储和处理带来了很大压力。本文设计了高速信号处理板与级联雷达芯片构成一套完整的毫米波多发多收(MIMO)成像系统。该系统为稀疏阵面,采用时分多址(TDMA)模式,使得系统兼具2个维度的高分辨率以及空间分辨能力,并且系统内部采用高速串行计算机扩展总线标准(PCI-Express),外部采用Thunderbolt3接口,均具备很高的通道传输速率,支持对目标区域进行实时成像。使用该系统可以从高分辨成像结果中提取有效的电磁特征,以更好地使用毫米波区分不同电磁特性的目标。最后,采用此系统开展点目标和复杂目标的成像试验,成像结果充分验证了该毫米波雷达可以有效测量不同类型目标的电磁特征,对不同电磁特性的目标具备一定的分辨能力及快速成像能力。

Single-chip millimeter wave radar has the shortcomings of single measurement dimension and low resolution. Cascaded radar chip can acquire the multi-dimensional information of a target,but the corresponding signal acquisition,storage,and processing are challenges. In this paper,a high-speed signal processing board and a cascade radar chip are designed to form a complete millimeter wave multiple-in multiple-out(MIMO)imaging system. The system is based on the sparse array and time division multiple access(TDMA)mode,and thus has the capabilities of high resolution and spatial resolution in two dimensions. It adopts the peripheral component interconnect express(PCIExpress)inside and Thunderbolt3 interface outside,both of which have a high channel transmission rate,and thus supports real-time imaging of the target area. The system can be used to extract effective electromagnetic features from high-resolution imaging results, so that the targets with different electromagnetic characteristics can be better distinguished with millimeter waves. Finally,the system is used to carry out imaging experiments for point targets and complex targets. The imaging results fully verify that the millimeter wave radar can effectively measure the electromagnetic characteristics of different types of targets,and has certain capabilities of resolution and fast imaging for targets with different electromagnetic characteristics.