A closed-form model for the forward scatter radar (FSR) signal is presented with the goal to overcome the far-field (FF) limitation of the commonly used models. The proposed Fresnel closed-form (FCF) model, based on an approximation of the Helmholtz–Kirchhoff electromagnetic theory, correctly represents the received field of rectangular metallic targets crossing the baseline either in the short range or long range of the FSR transmitter and receiver. The FCF model outputs are validated by comparison with numerical results of a full-wave simulation tool in terms of received field amplitude and phase. The FCF model is exploited to assess the FSR detection performance loss, caused by the use of the FF models for some case studies of practical interest. Based on the proposed FCF model, we provide an analysis of the FSR ideal optimum performance achievable in these scenarios.

中文翻译：

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来自矩形导电目标的长短程前向散射雷达信号的闭式模型

提出了前向散射雷达 (FSR) 信号的封闭形式模型，目的是克服常用模型的远场 (FF) 限制。所提出的菲涅耳闭式 (FCF) 模型基于亥姆霍兹-基尔霍夫电磁理论的近似值，正确表示在 FSR 发射器和接收器的短程或长程中跨越基线的矩形金属目标的接收场。FCF 模型输出通过与全波仿真工具在接收场幅度和相位方面的数值结果进行比较来验证。FCF 模型用于评估 FSR 检测性能损失，这是由于将 FF 模型用于一些具有实际意义的案例研究而引起的。基于提出的 FCF 模型，