利用360 GHz辐射计高空探测目标研究

Detecting Target with 360 GHz Radiometer at High Altitude

亚毫米波会被大气严重吸收,因此在底层大气中进行金属目标的被动探测很困难。提出了一种利用360 GHz亚毫米波辐射计在高空探测目标的方法。介绍了360 GHz辐射计系统的结构。利用MPM模型计算了大气辐射温度和目标的天线温度对比度。在地面温度为0℃、相对湿度为20%的天气条件下对辐射计进行了定标实验,并对地面上方3 m处的0.5 m×1m金属目标进行了探测试验。计算和试验结果表明,天线温度对比度的计算模型是可行的。在地面温度为20℃、相对湿度为20%的天气条件下,处于5 km高度的360 GHz辐射计对1 m×5 m目标的探测高度为0.3 km,而对10 m×20 m大目标的探测高度为2 km。

Submillimeter wave is absorbed in atmosphere seriously.So it is very difficult to detect a metal target in lower atmosphere passively.A method for detecting a metal target by a 360 GHz radiometer at high altitude is proposed.The configuration of the radiometer is presented.The contrast of the atmospheric radiation temperature to the antenna temperature of the target is calculated by using a MPM model.The radiometer is calibrated under the weather condition with the ground temperature of 0 ℃ and the humidity of 20%and is used to detect a 0.5 m×1 m metal target at the altitude of 3 m above the ground.The calculation and experimental results show that the model for calculating antenna temperature contrast is feasible.Under the weather condition with the ground temperature of 20 ℃ and the relative humidity of 20%,the 360 GHz radiometer at the altitude of 5 km can detect a 1 m×5 m metal target in the distance of 0.3 km above it and can detect a 10 m×20 m metal target in the distance of 2 km above it.