UHF波段小擦地角海杂波幅度均值修正模型

Modified reflectivity model of UHF-band sea clutter at low grazing angle

作为海杂波重要特性之一,幅度均值可为雷达系统设计提供支撑。为此,国际上建立多个经验模型,但由于小擦地角下散射机制复杂,而且测试条件存在差异,模型的适用性不强。基于黄海海域超高频波段水平极化小擦地角海杂波实测数据,开展了幅度均值经验模型的适用性分析。针对已有模型拟合程度较差的问题,初步分析了原因,并提出了一种修正技术服务公司(technology service corporation,TSC)模型。通过对TSC模型中擦地角因子和风向因子的改进,调整了幅度均值随参数的变化趋势,与实测结果对比发现,该模型较好实现了海杂波幅度均值的预测。

As an important characteristic of sea clutter,the reflectivity can support the radar system design.Thus,some empirical models are proposed around the world.However,the applicability of the models is not strong due to the complexity of scattering mechanism at the low grazing angle and the difference of test conditions.An applicability analysis is done by using the ultra high frequency(UHF)band horizontal polarized sea clutter data of the Yellow Sea at low grazing angle.Aiming at the poor fitting of the existing models,the reasons are preliminarily analyzed and a modified technology service corporation(TSC)model is presented.Through improving the grazing angle and wind direction factors in the TSC model,the trend of reflectivity varing with parameters is adjusted.Compared with the measured data,it is found that the proposed model can provide better prediction of reflectivity at the test sea area.