为了估算红外探测系统对巡航导弹的作用距离，首先构建了巡航导弹的简化模型，分析了各主要红外辐射源在3~5μm和8~12μm两个波段上的红外辐射特征；然后指出了既有的基于表观对比度作用距离模型的不足，针对此不足推导了适用性更广泛的作用距离方程，并给出了逐步逼近法求解该方程；最后通过算例求出结果并进行了分析。

To estimate the operating range of an infrared (IR) detection system to cruise missiles,a simplified model of cruise missile was built up.The radiation characteristics of each main source of IR radiation at wavebands of 3～5μm and 8～12μm and were analyzed.The insufficiencies of the existing model of operating range based on apparent contrast were pointed out,on which basis a modified operating range function was given.Then a step-by-step approximation method was presented for obtaining the feasible solution to the function.The computation result was analyzed at last.