Further Investigation of Ocean Remote Sensing Using High-frequency and Microwave Radars

近四十年来，高频表面波雷达（HFSWR）和微波航海雷达（MNR）已成为海洋遥感的重要工具。由于高频（3- 30mhz）信号与海洋重力波场之间的强相互作用，HFSWR能够提供“超视界”的海流、风、波和目标信息。日益频繁的海上活动（如运输、海上石油和天然气勘探）导致需要在浮动平台（如船舶或海上石油平台）上安装这种雷达系统。然而，一个主要的挑战是平台运动将通过扭曲雷达多普勒频谱而恶化雷达性能。高频雷达应用面临的另一个挑战是电离层杂波造成的污染。为了提高高频雷达的利用率，必须解决这两个问题。虽然在陆地或船上工作在10ghz左右的x波段MNR是一种“现场线”传感器，但它可以以相对较高的空间和时间分辨率对海面进行成像。然而，它的海面传感性能会受到降雨的负面影响。为了使这一广泛部署的系统在所有天气条件下提供实时信息，需要寻求雨水污染的对策。本提案旨在通过发展理论模型和应用算法来解决上述挑战。理论模型有望提供对海洋表面无线电波散射的更好理解，而应用算法将为高频和多波段雷达社区带来重要的资产，并可以集成到可能出口到国际的商业雷达产品中。本研究的长期目标是在加拿大东部和北极地区建立一个由HFSWR、MNR、全球导航卫星系统（GNSS）和合成孔径雷达（SAR）组成的广阔的沿海海洋观测网络。这样的网络将通过提供高质量的海面数据产品来提高海上安全，以满足加拿大国防部、渔业和海洋部、加拿大海岸警卫队和其他海洋利益相关者（如航运、石油和天然气行业）的持续需求。在NSERC的资金支持下，纪念大学将继续培养高素质的人才，以增强加拿大的雷达海洋遥感能力，并保持其在该领域的领先地位。

During the past four decades, both high frequency surface wave radar (HFSWR) and microwave nautical radar (MNR) have become important tools for ocean remote sensing. HFSWR is able to provide sea surface current, wind, wave and target information “over the horizon” due to the strong interactions between the HF (3-30 MHz) signal and the ocean gravity wave field. Increasingly frequent marine activities (e.g. transportation, offshore oil and gas exploration) result in the necessity for installing such radar systems on floating platforms (e.g., a ship or an offshore oil platform). However, a major challenge is that the platform motion will deteriorate the radar performance by distorting the radar Doppler spectra. Another challenge to the HF radar applications is contamination due to ionospheric clutter. To improve the utility of HF radar, both problems must be addressed.Although X-band MNR, which operates at around 10 GHz on land or ship, is a sort of “line-of-site” sensor, it can image the sea surface with relatively high spatial and temporal resolutions. Unfortunately, its performance in sea surface sensing will be negatively affected by rain. In order for this widely deployed system to provide real-time information under all weather conditions, countermeasures for rain-contamination need to be sought.The proposal aims to solve the above challenges by developing both theoretical models and application algorithms. The theoretical models are expected to provide an improved understanding of radio wave scattering from the ocean surface, while the application algorithms will bring significant assets to both HF and MNR radar communities and can be integrated into commercial radar products that may be exported internationally. A long-term goal of this research is to build a broad coastal ocean observation network that consists of HFSWR, MNR, Global Navigation Satellite Systems (GNSS) and Synthetic Aperture Radar (SAR) in Eastern Canada and Arctic regions. Such a network will improve marine safety through providing high quality sea surface data products to meet the ongoing needs of the Department of National Defence, Fisheries and Oceans Canada, the Canadian Coast Guard and other marine stakeholders such as the shipping and oil and gas industries. With financial support from NSERC, Memorial University will continue to train highly qualified personnel to augment the radar ocean remote sensing capacity of Canada and maintain its status as one of the leaders in this field.