...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>IEEE Transactions on Geoscience and Remote Sensing >Cross Calibration of the OceanSAT -2 Scatterometer With QuikSCAT Scatterometer Using Natural Terrestrial Targets
【24h】

Cross Calibration of the OceanSAT -2 Scatterometer With QuikSCAT Scatterometer Using Natural Terrestrial Targets

机译：使用天然地面目标的带有QuikSCAT散射仪的OceanSAT -2散射仪的交叉校准

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The accuracy of ocean surface wind vectors measured by satellite-borne scatterometers depends on measured backscattering coefficient $(sigma^{circ})$. Hence, an in-flight calibration of a satellite scatterometer is essential as this is not guaranteed by its prelaunch absolute calibration. The postlaunch calibration of $sigma^{circ}$ is also required to monitor the time evolution of the accuracy of measured $sigma^{ circ}$. This is performed using relative calibration over land targets with minor spatiotemporal variation of $sigma^{circ}$. A few such targets are the Amazon rainforest, Greenland, Antarctica, etc. In this paper, relative calibration of $ sigma^{circ}$ from the OceanSAT-2 Scatterometer (OSCAT) has been carried out by comparing it with a similar quantity from the Quick Scatterometer (QuikSCAT) for November 2009. The differences between the average $sigma^{circ}$ of QuikSCAT and that of OSCAT have been calculated globally to check the overall consistency. Over the calibration sites, the differences are within $pm$0.25 dB. Histograms of differences in ascending/descending passes and fore/aft looks of OSCAT have also been analyzed over the calibration sites. These indicate that look bias in OSCAT $sigma^{circ}$ is within the range of $pm$0.5 dB. It is also evident that pass biases, i.e., differences between ascending and descending passes, exist over the Ama- on rainforest for both QuikSCAT and OSCAT. This diurnal variation in $sigma^{circ}$ may go up to 1.25 dB in OSCAT. Further, computations of daily average and standard deviation over the calibration site show that mean OSCAT $sigma^{circ}$ is consistent with mean QuikSCAT $sigma^{circ}$, whereas the standard deviation in OSCAT is marginally higher. Further, time-series analysis of OSCAT $sigma^{circ}$ shows its temporal stability.
机译：由卫星散射仪测量的海洋表面风向矢量的精度取决于所测量的反向散射系数$（sigma ^ circ）$。因此，卫星散射仪的飞行中校准至关重要，因为这无法通过发射前绝对校准来保证。在启动后还需要对σ进行校准，以监视所测σ的准确性的时间演变。这是通过对土地目标进行相对校准而实现的，该目标的时空变化为$ sigma ^ {circ} $。其中一些目标是亚马逊雨林，格陵兰岛，南极洲等。在本文中，通过与OceanSAT-2散射仪（OSCAT）的$σ进行相对校准，方法是将其与来自CATCAT的相似量进行比较快速散布仪（QuikSCAT）于2009年11月发布。QuikSCAT和OSCAT的平均σ相加已在全球范围内进行计算，以检查总体一致性。在校准地点，差异在$ pm $ 0.25 dB以内。还已在校准站点上分析了OSCAT的上升/下降通道和前后外观的差异直方图。这些表明OSCAT $ sigma ^ {circ} $中的外观偏差在$ pm $ 0.5 dB的范围内。同样明显的是，QuikSCAT和OSCAT的热带雨林上均存在通行证偏差，即上升和下降通行证之间的差异。在OSCAT中，σ的这种昼夜变化可能高达1.25 dB。此外，在校准位点上的每日平均和标准偏差的计算结果表明，平均OSCAT标准与平均QuikSCAT标准一致，而OSCAT中的标准偏差略高。此外，对OSCAT的时间序列分析显示了其时间稳定性。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号