前言为了描述任何雷达的距离性能,必须在真实目标(战斗机、轰炸机、导弹等),或各种科学研究用标准目标之间作出选择。虽然,运动目标最适合用来代表现实世界,但是,由于其雷达截面积随视角有极大的变化,除非能取得大量统计采样,否则,通常必须把它看成仅是定性分析用的目标。还进一步要求对目标本身进行校准。因此,要获得对真实目标的定量分析结果,其费用是极高的。相反,用标准目标获得定量分析数据是经济的。角反射器、伦伯透镜、球体和有源应答器就是这类标准目标的一些例子。为了校准任何标准目标,球体是通常选用的,因为球体的 Foreword To characterize the performance of any radar, the choice must be made between real targets (fighter planes, bombers, missiles, etc.), or various standard goals for scientific research. Although moving targets are best suited to represent the real world, their radar cross-sectional area varies greatly from perspective to perspective, and unless large amounts of statistical sampling are available, it must often be viewed as merely a goal of qualitative analysis. It further requires that the target itself be calibrated. Therefore, to get the quantitative results of the real target, the cost is very high. In contrast, it is economical to obtain quantitative data using standard objectives. Corner reflectors, Luneberg lenses, spheres and active transponders are some examples of such standard targets. In order to calibrate any standard target, the ball is usually selected because of the ball’s