地球静止轨道综合孔径大气微波探测仪成像理论与方法研究

Extending the microwave radiometers to geostationary earth orbit (GEO) is now very demanding for meteorological research and weather forecasting. Several concepts of launching a GEO microwave atmospheric sounder have been proposed by NOAA, NASA and ESA in the last decade. China has also made a clear schedule for developing a separate microwave series of the next generation meteorological satellites, named as FY-4M. This research is aiming at the future GEO mission in China and dedicated to solve the theoretical and scientific problems encountered by the circular array synthetic aperture radiometer in application of high accurate atmospheric sounding from GEO, as a potential payload of FY-4M. Some scientific issues will be focused such as the sampling theory and fast inverse Fourier transform on uneven polar grid, optimization theory of antenna elements distribution in a circular array, highly accurate image reconstruction algorithm, system calibration and error correction and so on. At last a system design will be carried out to meet the user requirements of atmospheric sounding. All the theoretical results will be tested and validated by numerical simulations and also field experiments by using the ground demonstrator. The approaches obtained by this research will be helpful to extending this new concept of circular array synthetic aperture radiometer to real applications, and also directly serve for China future GEO microwave meteorological satellite mission.

静止轨道大气微波探测是目前气象遥感所急需开展的新领域，在静止平台上搭载微波成像仪可提高大气温/湿度廓线探测的时间分辨率，同时也提高对云雨和台风的探测能力，可以对台风内部结构、降雨分布、移动路径等关键参数进行连续探测。目前世界气象卫星大国都提出了自己的研究计划，我国也明确列出了风云四号静止轨道微波星的气象卫星发展规划。本项目瞄准静止轨道大气探测应用，以高精度定量遥感为出发点，对具有自主知识产权的旋转扫描圆环阵综合孔径技术的成像理论进行深入研究。建立非均匀极网格采样理论和分析方法、天线阵优化理论与方法、高精度成像反演算法、系统定标和误差校正方法；完成静止轨道大气探测应用的方案设计和成像仿真模型；并开展样机实验对研究结果进行验证。本项目的研究成果将有助于推动这种新型体制的综合孔径辐射计技术走向实际应用，并有望服务于我国未来的静止轨道微波气象卫星计划。

本项目通过对静止轨道旋转扫描综合孔径辐射计成像理论开展研究，完善了非均匀极网格移动采样理论，提出了新的天线阵采样性能分析方法；建立了高效的圆环天线阵优化方法并针对未来静止轨道大气探测应用进行了不同频段和需求的天线阵优化设计；建立了适合旋转扫描成像体制的高精度成像反演算法和系统定标及误差校正方法；完成静止轨道大气探测应用的方案设计和成像仿真模型，通过数值仿真和实际样机测试实验对研究结果进行综合验证，为未来我国静止轨道气象卫星FY-4M的顺利实施奠定理论基础，并为被动微波遥感领域的其它综合孔径体制的微波辐射计载荷设计提供理论指导。