Ocean Remote Sensing Using High-frequency and Microwave Radars

高频地波雷达(HFSWR)和微波航海雷达(MNR)广泛应用于海洋遥感。高频地波雷达通过高频无线电波和海洋重力波的相互作用，“在地平线上”提供海面流、风、浪和目标信息。传统上，高频地波雷达系统一直是陆基的；紧凑型舰载高频地波雷达也被使用，但由于平台运动，多普勒频谱容易失真。目前使用的大多数高频地波雷达系统依赖于单站配置，其中发射和接收组件位于同一位置。为了降低成本并潜在地提高覆盖范围，有必要研究高频雷达的双基地工作--即发射和接收发生在不同的地点。还可以从包含海面时空结构的MNR图像中提取海面信息。MNR提供的海面信息具有更好的距离分辨率，但覆盖范围有限。为了为搜救、溢油控制和海洋导航等领域的应用提供实时信息，需要对MNR进行进一步的研究。

High frequency surface wave radar (HFSWR) and microwave nautical radar (MNR) are widely employed in ocean remote sensing. HFSWR provides sea surface current, wind, wave and target information "over the horizon" due to the interaction of HF radio and ocean gravity waves. Traditionally, HFSWR systems have been land-based; compact ship-borne HFSWR has also been used but is subject to distortion of the Doppler spectra due to platform motion. Most HFSWR systems in use rely on a monostatic configuration in which the transmitting and receiving components are at the same location. In order to reduce the cost and potentially improve coverage, research on operating HF radar bistatically - i.e. transmission and reception occur at different sites - is necessary. Sea surface information can also be retrieved from the MNR images that contain the spatial and temporal structure of the ocean surface. MNR provides sea surface information with better range resolution but has limited coverage. In order to provide real-time information for applications in areas such as search and rescue, oil spill control and marine navigation, MNR needs to be further investigated.