基于全球导航卫星系统(GNSS)反射信号的海冰检测模型的研究

基于导航反射信号的双基表面反射原理可以实现海风海浪和陆地土壤湿度的检测，但是基于导航反射信号的海冰检测，目前国内还没有相关的研究。此外，目前也需要验证反射信号的海冰双基反射模型的有效性。前期的研究显示双极化反射信号的幅度极化比和海冰表面的介电常数变化之间的联系,证明了幅度极化比值与海冰的形成和消融过程中海冰密集度有明显的关系。本项目拟通过分析GNSS 海冰反射信号的数据，证明冰块的有效介电常数和表面粗糙度是海冰检测中的有用信息。在已有的海面反射信号分析理论的基础上，确定冰面反射信号分析和阈值。调查海冰与海水的不同盐度的反射信号的特征， 确定海冰的临界线。建立海冰的反射-折射模型，确定海冰的厚度。建立初冰表面概率密度函数模型（PDF），确定海冰的冰龄。理解基于GNSS-R 的海冰反射的原理，为进一步利用GNSS-R 实现海冰遥感和极地海冰研究提供理论基础。

It has been proved that bistatic scatteting of navigation reflection signal can be used to perform sea wind speed and wave height measurements, and can also be used to perform land soil moisture detection. However, there is no study on reflection signal off sea ice in the current domestic related research. In addition, it also requires more thorough verification to prove effective of navigation signal bistatic scatteting model on sea ice. Data from Global Navigation Satellite System Reflection (GNSS-R) signal off sea ice, which includes sea ice and ocean surface roughness and other useful information, can achieve sea ice area and thickness measurements. Advanced studies demonstrate the parametric ratio has an apparent evolution with the complex dielectric constant，the different normalized ratio of the reflected signal is closely linked with the sea ice formation and ablation procedure. This research is planned to analysis data from GNSS-R off sea ice, to prove that effective dielectric constant of ice and ice surface roughness are useful in sea ice detection. Because sea ice roughness has a distinctly different character than that of waves on a wind driven ocean surface, and salt of sea ice is also very different than that of ocean, bistatic scatteting from sea ice should differ from ocean bistatic scatteting, we can detect the difference between reflected signal characteristics on sea ice and ocean, to determine boundary between sea ice and ocean to estimate sea ice area. Because GNSS signal can penetrate the thin ice, reflection coefficient for thin ice might be affected by the underlying sea ice, establishing sea ice reflection-refraction model can estimate sea ice thickness. Because Young ice surface topography is different significantly from Old ice, establishing effective Young sea ice surface probability density function model (PDF) can decide sea ice age. That understanding the theory of GNSS-R off sea ice can provide theoretical basis to further realize the use of GNSS-R remote sensing off sea ice and arctic ice research.