基于机载相控阵海浪波谱仪的海浪谱测量  

Wave spectra measuring from airborne phased-array wave spectrometer

作　　者：江柏森 韩倩倩 曹蕾 张晰 叶洪玲 Jiang Bosen;Han Qianqian;Cao Lei;Zhang Xi;Ye Hongling(Microwave Remote Sensing Department,Beijing Research Institute of Telemetry,Beijing 100010,China;Ocean Telemetry Technology Innovation Center,Ministry of Natural Resources,Beijing 100010,China;First Institute of Oceanography,Ministry of Natural Resources,Qingdao 266061,China)

机构地区：[1]北京遥测技术研究所微波遥感技术研究室,北京100010 [2]自然资源部海洋遥测技术创新中心,北京100010 [3]自然资源部第一海洋研究所,青岛266061

出　　处：《仪器仪表学报》2024年第5期129-137,共9页Chinese Journal of Scientific Instrument

基　　金：CFOSAT及海风海浪卫星专项研究基金(2023CFO003)项目资助。

摘　　要：提出一种机载相控阵海浪波谱仪,是Ku频段、线极化二维相控阵列雷达,发射宽带线性调频信号,在小入射角下照射海面,接收被海面准镜面散射调制的回波功率,获取海面后向散射系数,反演得到一维海浪谱。通过二维相控阵实现0~360°方位向的圆锥扫描,获取二维海浪方向谱,进而计算波高、波向、波长等海浪参数产品。一方面,采用基于二维相控阵的动态波位驻留时序设计,将均匀扫描改为非均匀扫描,增加沿航向的观测时间,提高沿航向斑点噪声抑制水平,改善了中法海洋卫星SWIM载荷的“沿航向信斑比不足”的问题,使观测效能得到提升;另一方面,采用电子扫描,无旋转机构,可大幅度提升波谱仪设备的紧凑性、适装性和可靠性,提高机载平台适应能力。在秦皇岛附近的渤海海域开展了相控阵海浪波谱仪飞行试验,与同步波浪浮标观测数据进行对比,结果表明相控阵海浪波谱仪波向测量精度优于15°,波长测量精度优于10%,有效波高测量精度优于0.3 m,验证了动态波位驻留对沿航向斑点噪声的抑制能力,以及相控圆锥扫描体制获取海面回波、反演海浪谱的性能。This study proposes a new airborne phased-array wave spectrometer(PAWS),which is a Ku-band,linear polarization two-dimensional phased-array radar.It transmits a wideband linear frequency modulation signal,illuminates the sea surface at a low incidence angle,and receives echo power modulated by quasi-specular reflection from the sea surface.From the echo power,the sea surface backscattering coefficient and the one-dimensional wave spectrum can be retrieved.With conical scanning from 0°to 360°,two-dimensional wave spectrum,and main wave parameters are obtained by PAWS as well,such as significant wave height,wave direction,and wavelength.On one hand,the dynamic beam position chronogram design(DBCD)benefited from the two-dimensional phased array radar is adopted.For the extension of observation time and the suppression of speckle noise of the along-track,it makes non-uniform scanning possible instead of uniform scanning to improve the insufficient along-track signal-to-speckle noise ratio of CFOSAT SWIM.Thus,better efficiency of PAWS is achieved.On the other hand,electrical scanning of the phased-array radar without a rotating mechanism can greatly improve the compactness,adaptability,and reliability of PAWS.Therefore,it can be mounted on various aircraft platforms.The PAWS field campaign was held in the Bohai Sea near Qinhuangdao in 2023,with synchronous buoys moored there.The results show that the accuracy of PWS’s dominant wave direction is better than 15°,the accuracy of the dominant wavelength is better than 10%,and the significant wave height is better than 0.3 m.The DBCD is proven to work for the suppression of the speckle noise along the track.The performance of the phased-array conical scanning for receiving sea surface echoes and retrieving wave spectra is also verified.

关 键 词：相控阵海浪波谱仪 海浪谱 机载雷达 

分 类 号：TH841[机械工程—仪器科学与技术]