| 摘要: |
| [目的]建立与观测数据相符的海浪波谱仪(SWIM)散射模型。[方法]利用Kirchhoff近似以及准镜面散射理论,建立从海浪方向谱映射到海浪波谱仪后向散射截面(σ°)的散射模型,并利用热带降雨测量卫星(TRMM)所搭载的降雨雷达(PR)提供的低入射角下的后向散射截面数据,对模型进行检验。[结果]准镜面散射模型结合高阶Gram-Charlier级数型海表斜率概率密度函数,模拟的雷达后向散射截面与入射角的关系在降雨雷达的0~18°入射角范围内与实测数据一致。[结论]海浪波谱仪的信号散射可利用准镜面散射模型结合高阶Gram-Charlier级数型海表斜率概率密度函数来描述。 |
| 关键词: 海浪波谱仪 后向散射截面 准镜面散射 |
| DOI： |
| 投稿时间：2015-05-08 |
| 基金项目:国家自然科学基金项目(41076119),江苏省自然科学基金项目(BK2011008),江苏省高等教育优势学科项目和2015遥感青年科技人才创新项目资助。 |
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| Sea Surface Scattering Model for SWIM |
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CHU Xiao-qing1, HE Yi-jun2
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| (1.State Key Laboratory of Tropical Oceanography(South China Sea Institute of Oceanology, CAS), Guangzhou, Guangdong, 510301, China;2.School of Marine Sciences, Nanjing University of Information Science & Technology, Nanjing, Jiangsu, 210044, China) |
| Abstract: |
| [Objective] A sea surface scattering model was established in order to agree well with measurement data for SWIM (Surface Waves Investigation and Monitoring).[Methods] The forward transfer function from sea surface directional wave spectrum to normalized radar cross section (NRCS, σ°) was developed based on Kirchhoff approximation and quasi-specular reflection theory.Precipitation radar (PR) on the Tropical Rainfall Mapping Mission (TRMM) provides NRCS at low incidence angles.The model is tested using measurements from PR.[Results] By using the quasi-specular scattering theory, combined with Gram-Charlier expansion of probability density function of wave slopes to the forth order, the modeled NRCS agrees well with radar measurements from nadir to 18°.[Conclusion] For SWIM, the sea surface scattering can be presented by quasi-specular scattering theory, combined with Gram-Charlier expansion of probability density function of wave slopes to the forth order. |
| Key words: SWIM normalized radar cross section quasi-specular scattering |
