Radio Wave Scattering from Rough Surfaces -- Theory and Application to Maritime Remote Sensing with HF and other Radar Technologies

近50年来，各种类型的雷达在新型海洋遥感应用中发挥了重要作用。申请人的研究小组成员在研究高频表面波雷达(波长为10至100米)以及最近的X波段航海雷达(波长为4至10厘米)方面一直处于领先地位。此外，还使用了工作在超高频(VHF)(1-m波)到超高频(UHF)(1.6-m波)低频段的雷达来研究海冰的特性。最近，该小组开始将典型工作波长约为24、6和3厘米(L波段、C波段和X波段)的卫星和机载合成孔径雷达纳入其用于测量海况、天气状况以及地面覆盖和湿地特性的遥感仪器库。高频驻波雷达的分辨率比高频雷达低得多，但高频驻波雷达信号可以用来探测海面上和附近的海洋状况和物体，如船只、冰山和低空飞行的飞机，远远超出视线范围。在拟议的研究计划下，对基本电磁散射理论和算法的改进将导致在海况非常高的情况下从雷达信号中提取海洋目标和环境信息(如波高、表面流、风速)的能力。还将随之而来的是更好地表征电离层信号污染和改进海洋平台的HFSWR操作。这一结果将对海洋学家和搜救操作员具有重要意义，并将提高近海石油和天然气行业等商业企业的安全性。高频地波雷达的低分辨率将通过改进的图像处理技术得到增强，但X波段雷达的分辨率要高得多。涉及用于合成孔径雷达应用的深度学习的算法开发也将增强对湿地和沿海水域的整体观测能力。除了上述举措外，还将继续调查使用甚高频-超高频频率来确定海冰和冰脊的特性，随着商业和领土利益越来越集中在加拿大北极，这是一个越来越重要的话题。NSERC在支持加拿大成为雷达遥感理论和应用方面的世界领先者方面发挥了关键作用，同时导致该技术在国际上的出口。拟议的工作将继续吸引科学、商业和海上安全利益。也许最重要的是，根据拟议的计划，通过培训高素质人员而培养的基本分析、计算和批判性思维技能将对加强加拿大的能力至关重要，不仅在海事应用方面，而且在许多工业环境中(例如。汽车和自然资源部门)，在这些领域，这类技能正变得越来越重要。

For almost 50 years, radars of various kinds have become important in novel ocean remote sensing applications. The applicant's research team members have been leaders in investigating high frequency surface wave radars (HFSWRs) (wavelengths of 10 to 100 metres (m)), and, more recently, X-band nautical radars (of 4 to 10 centimetre wavelengths).   In addition, radars operating in the upper very high frequency (VHF) (1-m waves) to lower ultrahigh frequency (UHF) (1.6-m waves) bands have been used to study the properties of sea ice. Very recently, the team has begun to include satellite and airborne synthetic aperture radars (SAR), with typical operating wavelengths around 24, 6 and 3 centimetres (L-, C- and X-band), in their arsenal of remote sensing instrumentation for measuring sea state, weather conditions, and ground cover and wetlands properties. HFSWR resolution is much lower than that of the higher-frequency radars, but HFSWR signals can be used to detect ocean conditions and objects such as ships, ice and icebergs, and low-flying aircraft, on and near the surface, well beyond the line-of-sight horizon. Under the proposed research program enhancements to fundamental electromagnetic scattering theory and algorithms will lead to the ability to extract maritime target and environmental information (eg., wave heights, surface currents, wind velocities), from the radar signals when sea states are very high.  Better characterization of ionospheric signal contamination and improved HFSWR operation from ocean platforms will also ensue. The results will be important to oceanographers and search and rescue operators, and will enhance safety in commercial ventures such as the offshore oil and gas industry. The lower-resolution of HFSWR will be augmented by improved image processing techniques for the much-higher-resolution, howbeit line-of-site, X-band radars.  Algorithm development involving deep learning for SAR applications will also enhance the overall capacity for observation of wetlands and coastal waters. In addition to the above initiatives, investigations will continue on using VHF-UHF frequencies to determine the properties of sea ice and ice ridges, an increasingly important topic as commercial and territorial interests become focused on the Canadian Arctic. NSERC has been crucial in supporting Canada as a world leader in both theoretical and applied aspects of radar remote sensing, while leading to the export of the technology internationally. The proposed work will continue to attract scientific, commercial and maritime security interests. Perhaps most-importantly, the essential analytical, computing and critical thinking skills developed by the training of highly qualified personnel under the proposed program will be vital in bolstering Canada's capacity, not only in maritime applications, but also in many industrial settings (eg. the automotive and natural resource sectors), where such skills are becoming increasingly important.