雷达电磁信号的多径传播仿真研究

Study of Multi - path Propagation Simulation of Radar Signal

从工程实际出发,系统研究雷达天线到目标间的电磁信号,受地形和地球曲率等因素影响而产生的多径传播问题。分别建立雷达电磁波在干涉区、中间区和绕射区传播的数学模型和它们适用的边界条件。给出了应用Mathmatic软件提供的InterpolatingPolynomia[data,x]多项式内插技术求解由干涉区平滑过渡到绕射区的中间区场强计算问题,并对雷达电磁信号在各区中的电磁传播作了仿真,来模拟雷达发射机经天线向空间辐射并到雷达接收机输入端的信号强度。此外,为了便于从电子地图中查找反射点区域的电磁反射特性,还给出了应用球面三角形计算反射点地理位置的求解方法。实验结果表明,该文不仅有助于雷达对抗战场环境的内场注入式仿真研究,而且对雷达系统的性能分析也将具有十分重要的参考价值。

The electromagnetic signal existing between the radar antenna and targets, will produce multi - path propagation problem by landform and earth curvature. This paper systematically studies the problem from the aspect of engineering practice. The mathematical models and their limitative condition of radar electromagnetic wave propagated in interference region, intermediate region and diffraction region are set up respectively. The technique of Interpolating Polynomial provided by the Mathematic Software is applied to calculate field intensity from interference region to the intermediate region of diffraction region. The electromagnetic wave transmitted in those fields is also simulated to calculate signal intensity. Those signals are eradiated from radar transmitter to the space, echoed by objects and received by radar receiver. Moreover, to find the electromagnetic reflection characteristic of reflection point form the e-lectronic map easily, a new technique is advanced to calculate geography position of reflection point with spherical triangle. The experiment results indicate that it is not only useful for the battle environment simulation for the injecting research of radar countermeasures , but also has the important reference value to radar performance analyzing.