阵列激光合成孔径雷达高分辨成像技术研究

Array Synthetic Aperture Ladar with High Spatial Resolution Technology

激光合成孔径雷达将合成孔径技术应用于激光频段,分辨率不受观测距离的限制,可实现远距离、超高分辨率成像。然而,受激光衍射极限限制,观测视场制约着激光合成孔径雷达对地观测实际应用。该文提出一种阵列激光合成孔径雷达技术体制,通过大功率阵列发射、阵列平衡探测接收、逐脉冲动态内定标实现了激光多路相干收发,成倍地扩大了成像视场。地面转台成像试验表明,成像分辨率优于3 cm(距离)×1 cm(方位),该项技术可为激光合成孔径雷达对地观测应用奠定基础。

By extending synthetic aperture technology from the microwave band to the laser wavelength,Synthetic Aperture Ladar(SAL)has long-distance imaging and extremely high spatial resolution independent of the target distance.Presently,the small field of view is the key constraint in SAL ground observation because of the laser diffraction limitation.In this paper,an array SAL technology is proposed.With high-power array transmission,array-balanced detection,and pulse-wise dynamic internal calibration,a multichannel coherent laser transceiver is realized.Meanwhile,the field of view has multiplied.The results of turntable experiments show that the imaging resolution is better than 3 cm(distance)×1 cm(azimuth).This technology provides a scientific and technical approach to SAL with wider swath imaging in ground observation.