基于一致性几何绕射理论的曲面目标谐振散射机理研究

      Research on resonant scattering mechanism of curved target based on uniform geometrical theory of diffraction

      • 摘要: 位于谐振区的雷达目标可由极点特征进行识别,但极点特征的物理意义及其对应的谐振机理并不明确。针对该问题,本文利用一致性几何绕射理论(uniform geometrical theory of diffraction, UTD),研究了曲面绕射的谐振机理,并提出了一种用于谐振区含曲面目标识别的极点正向推算方法。首先,用投影递推寻迹算法在目标表面获取爬行波的闭合路径及几何参数;然后,基于UTD给出曲面绕射场表达式,推导出用于预测极点的谐振方程;最后,通过对理想导体球及椭球进行极点预测,与频域仿真提取的极点进行对比,综合误差在5%以内,验证了建模方法的准确性。

         

        Abstract: Radar targets positioned within the resonance region can be identified by the natural poles; nonetheless, the physical connotation of the natural poles and the corresponding resonance mechanism remain ambiguous. To solve the diffraction problem, the resonant mechanism of a surface diffraction is explored by resorting to the uniform geometrical theory of diffraction (UTD), and a forward pole computational methodology is proffered for the identification of a target encompassing curved surface within the resonance region. Primarily, the closed path and geometric parameters of the creeping waves are obtained on the surface of the target by employing the projection recursive tracking algorithm. Subsequently, based on UTD, the expression of the curved surface diffraction field is proffered, and the resonance equation for predicting the poles is deduced. Ultimately, the poles of the ideal conductor sphere and spheroid are predicted and compared with the poles extracted from the frequency domain simulation. The comprehensive error is less than 5%, thereby validating the accuracy of the modeling approach.

         

      /

      返回文章
      返回