Spaceborne GNSS reflectometry for ocean winds: First results from the UK TechDemoSat-1 mission
Spaceborne GNSS reflectometry for ocean winds: First results from the UK TechDemoSat-1 mission
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DOI：
10.1002/2015gl064204
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发表时间：
2015-07-16
影响因子：
5.2
通讯作者：
Rosello, Josep
中科院分区：
文献类型：
--
作者：
Foti, Giuseppe;Gommenginger, Christine;Rosello, Josep
第一个结果是从低地球轨道英国TechDemoSat-1卫星（TDS-1）测量的反射GPS信号的海洋表面风速检索。TDS-1于2014年7月发射，提供了自2003年开创性的英国灾害监测使命（UK-DMC）实验以来的第一个新的星载全球导航卫星系统反射测量（GNSS-R）数据。机载处理的延迟多普勒地图的例子显示，风高达27.9米/秒的数据质量很好。利用ASCAT风速数据，提出了一种基于信噪比和双基地雷达方程的风速算法。对于信噪比大于3dB的风速，即使没有校准，也可以在3和18 m/s之间无偏差地获得约2.2m/s的精度。然而，利用较低的SNR信号需要对天线波束、平台姿态和仪器增益设置有很好的了解。这项研究展示了低成本、低质量和低功耗GNSS-R接收器的能力，这些接收器将于2016年在NASA Cyclone GNSS（CYGNSS）星座上发射。
First results are presented for ocean surface wind speed retrieval from reflected GPS signals measured by the low Earth orbiting UK TechDemoSat-1 satellite (TDS-1). Launched in July 2014, TDS-1 provides the first new spaceborne Global Navigation Satellite System-Reflectometry (GNSS-R) data since the pioneering UK-Disaster Monitoring Mission (UK-DMC) experiment in 2003. Examples of onboard-processed delay-Doppler maps reveal excellent data quality for winds up to 27.9m/s. Collocated Advanced Scatterometer (ASCAT) winds are used to develop and evaluate a wind speed algorithm based on signal-to-noise ratio (SNR) and the bistatic radar equation. For SNRs greater than 3dB, wind speed is retrieved without bias and a precision around 2.2m/s between 3 and 18m/s even without calibration. Exploiting lower SNR signals, however, requires good knowledge of the antenna beam, platform attitude, and instrument gain setting. This study demonstrates the capabilities of low-cost, low-mass, and low-power GNSS-R receivers ahead of their launch on the NASA Cyclone GNSS (CYGNSS) constellation in 2016.