机载毫米波合成孔径对地观测相机:原理与天线阵构型

Synthetic Aperture Millimeter-wave Camera of Airborne for Earth Observations: Principles and Configurations of Antenna Array

被动式毫米波合成孔径相机是不需要毫米波源进行接收被观察目标的辐射信号成像的、有潜在应用前景的遥感新技术,它具有系统简单、成本低、实时成像、高的分辨率和近全天候工作等特点,已引起军事部门和科学研究部门的重视。针对机载对地观测的应用情况,介绍了被动毫米波合成孔径成像的原理和Y-构型和T-构型天线阵的性能。模拟计算表明:1在飞机飞行高度为10000m高度时、带宽为(f=100MHz、视场角为±30°的情况下,8mm波段的地表辐射功率约为9.0W,3mm波段的地表辐射功率约为68.0W,说明机载遥感是可行的。2Y-型天线构型的可见度函数的覆盖要大于T-型天线构型的可见度函数的覆盖,Y-型天线构型的角分辨率也高于T-型天线的角分辨率。

A new technology of passive millimeter-wave aperture synthetic camera is an imaging technology that can receive the radiation from observed objects and does not require a millimeter-wave source and have potential applications. It offers very significant advantages of simpler system, lower cost, real-time imaging, higher resolution and near-all-weather capability etc. as well as has arisen attentions of scientific and military surveillance. In this paper, aimed at circumstances of earth observations of airborne, the principles of passive millimeter-wave aperture synthetic imaging are introduced, the results of simulated computation show that: (a) In cases of 10000 meter height, 100 MHz width of frequencies and ±300 field of view, the emitted power from terrain is 9.0 watt for 8 mm waveband and 68.0 watt foe 3mm waveband respectively. Such a radiation power is sufficient for airborne remote sensing. (b) The coverage of visibility function and angle resolution foe Y-type of antenna arrays is better than T-type of antenna arrays. The results of this paper are helpful for design of systems for passive millimeter-wave aperture synthetic imaging of airborne.