空中红外目标探测的虚警源———飞鸟

在对空中目标进行红外探测时，飞鸟是一种重要的潜在虚警源，其具有和目标相似的红外辐射特性。首先对飞鸟和空中目标在探测器上信号的计算方法进行了讨论，重点考虑了红外系统的聚焦位置对成像的影响；然后根据得到的公式分析了飞鸟飞行高度、面积和系统聚焦位置对飞鸟在探测器上信号的影响，同样也对目标的信号进行了分析，分析结果表明:从信号的特征上不能区分飞鸟和目标；最后提出了从速度的观点对飞鸟和目标进行区分的方法，对飞鸟可能成为虚警源的概率公式进行了推导和示例计算，从计算结果可以看到，通过速度的差别，可以在很大程度上对飞鸟进行剔除。

False alarm source in air IR target detection-birds

When to detect an air target in infrared, bird is a potential source of false alarms, its IR characteristics are similar to the target's. The way to calculate the signal of the bird and target on the detector was firstly discussed, and the effects of the IR system's focus position were specially considered. Secondly, the influences that the flight altitude, area and focus position of system have on the bird's signal on the detector were analyzed according to the obtained formula. The signal of the target was also analyzed through the same way. The results show that the bird and the target can not be discriminated by the signal characteristics. Lastly, the way to discriminate the bird and the target was proposed based on the velocity, and the formula of probability that the bird would be treated as a false alarm was deduced and the calculation examples were done. From the results, it can be seen that the bird can be eliminated largely by the differences in velocity.