用于交通监测的机动车轮毂散射特性

提出了一种利用机动车轮毂正交极化散射实现交通流量监测方案,研究分析了机动车轮毂极化电磁散射特性,得出了优化参数。通过建立汽车和轮毂模型,仿真得到主模谐振频率为255 MHz,比较了入射波激励为线极化平面波时,汽车和轮毂主极化、正交极化雷达散射截面(RCS)的大小,并得到了单个轮毂正交极化雷达散射截面达到最大值时的入射角。仿真比较了入射波极化角度改变时,RCS 的空间分布特点。分析表明:轮毂目标VH 极化散射最显著;将雷达天线放置于与机动车轮毂中心相对地面同等高度处,可有效减小机动车框架对轮毂散射场的影响,研究结果对于构建经济有效的机动车交通管制系统具有实际意义。

The Scattering Characteristic of Vehicle Wheel Hub for the Traffic Monitoring

A traffic flow monitoring method is proposed by using the orthogonal polarization scattering of motor vehicle hub. The electromagnetic scattering characteristics of motor vehicle hub which can be used for urban traffic flow monitoring are studied and analyzed. The optimized parameters are obtained by the practical application. By establishing the model of the automobile and the hub, the resonance frequency of the main mode is 255 MHz. The comparison of the radar polarization cross section (RCS) of the main and orthogonal polarizations of the automobile and the hub when the orthogonal polarization incident wave is excited as an ordinary plane wave and a single result is obtained. The angle of incidence at which the hub radar cross section reaches its maximum is obtained. The spatial distribution characteristics of RCS are simulated when the polarization angle changes. The analysis shows that the VH polarization scattering of the hub target is the most significant; positioning the radar antenna at the same height as the center of the hub of the motor vehicle wheel can effectively reduce the impact of the vehicle frame on the wheel''s scattering field. The research results are useful for constructing an economically efficient machine. The train control system has practical significance.