本文用一致性几何绕射理论(UTD)分析和计算了带有两个共平面翼板的理想导电圆柱的远区散射场。应用了等效源概念处理了由翼板边缘绕射后沿翼板表面向圆柱传播的波。还提出了镜象射线的概念,利用这种概念可以简化经历反射和曲面绕射的复杂射线场的计算。把用UTD计算的结果和用矢量柱面波展开法求得的解析解结果作了比较,两种结果相当一致。 In this paper, the far-field scattering field of an ideal conducting cylinder with two coplanar flanges is analyzed and calculated by the UTD method. The concept of equivalent source was used to deal with the wave propagating along the wing surface towards the cylinder after being diffracted by the edge of the wing. Also proposed the concept of mirror radiation, the use of this concept can be simplified through the reflection and surface diffraction of complex ray field calculation. The result of UTD calculation is compared with the analytical solution obtained by vectorial cylindrical wave expansion method, and the two results are quite consistent.