基于一致性幾何繞射理論分析飛機機體結構對安裝在機背上的雙脊喇叭天線輻射特性的影響，分析了機載雙脊喇叭天線各輻射場分量的計算方法，計算了天線經簡化機體散射后的方向圖。仿真實驗結果表明，機體對天線輻射特性的影響主要在機身表面的反射、結構邊緣的繞射，而表面爬行波對天線方向圖主瓣的影響非常小，其影響主要在后瓣。計算結果可為天線安裝后輻射性能預測和最優化配置提供理論依據。In this paper, the Uniform geometrical Theory of Diffraction(UTD)is first time employed in conjunction with approximate models of the aircraft structure to analyze the effect of aircraft for double-ridged horn pattern on the top fuselage and to analyze the scattering field formulas effected by aircraft structure. The scattering fields are computed while the radiation pattern of double-ridged horn antenna mounted on the top of an aircraft is obtained. The simulation results show that the effect of the aircraft on radiation pattern is the surface reflecting field, the edge scattering field, and the surface creep wave which contributes to the backload of the pattern. The results of this paper can be used to analyze the radiation pattern of airborne antenna and to optimize the airborne antenna disposition.