Air-to-ground ranging (AGR) is one of the important operation modes of an airborne monopulse radar system. Here, an approach for the detailed modelling and simulation of the AGR performance of such a radar system over complex terrain is proposed. Time-domain monopulse signals reflected by the terrain's surface were modelled using the dynamics of the airborne platform, clutter properties, and RF specifications of the radar, which included the operating frequency, antenna beam patterns, and pulse repetition time. The AGR performance was then numerically analysed by employing the modelled monopulse return signals and a digital elevation model of the terrain's surface. Several crucial factors affecting the accuracy of line-of-sight estimation, including shadowing effects and roll stabilisation, were addressed using numerical simulations of various scenarios.

中文翻译：

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复杂地形机载单脉冲雷达空对地测距模式仿真

空对地测距（AGR）是机载单脉冲雷达系统的重要操作模式之一。这里，提出了一种用于在复杂地形上对这种雷达系统的AGR性能进行详细建模和仿真的方法。利用机载平台的动力学，杂波特性和雷达的RF规格（包括工作频率，天线波束方向图和脉冲重复时间）对地形表面反射的时域单脉冲信号进行建模。然后，通过使用建模的单脉冲返回信号和地形表面的数字高程模型，对AGR性能进行数值分析。影响视线估计准确性的几个关键因素，包括阴影效应和侧倾稳定，