利用机载GNSS-R的有效波高反演技术

采用自主研发的多源多宿GNSS-R(Global Navigation Satellite System-Reflections,全球导航卫星系统反射信号)海洋环境遥感探测系统,在天津渤海湾特定区域进行了3次机载校飞试验,获得了大量有效GNSS-R信号数据,对自然条件下的海面有效波高进行了反演处理。该系统通过对接收的GNSS直达信号和海面反射信号进行相关运算处理,可以获得DDM(Delay-Doppler Mapping,时延—多普勒映射)图谱,再利用DCF(Derivative of the Correlation Function,相关函数的导数)在DDM图谱基础上进行相关功率波形的计算,进而通过计算DCF的函数波形宽度得到海面有效波高,验证了该方法的可行性。该方法具有全天时、全天候、高分辨率、低成本等优点,对全球范围内中小尺度海洋状态和物理现象的监测具有重要意义。

A Method of Retrieval of Significant Wave Height Using Airborne GNSS-R

A marine environment remote sensing system based on multi source and multi-destination Global Navigation Satellite System-Reflections(GNSS-R)technology is introduced in this paper. The system was independently developed and used in three airborne flight tests in specific area of Bohai Bay near Tianjin. A significant amount of effective GNSS-R signal data was collected and significant wave height under natural conditions was retrieved. The system received GNSS direct signals and reflected signals of the sea, then generated Delay-Doppler Mapping(DDM) imagery by correlation process of the signals. Correlation power waveform of the DDM map was calculated using Derivative of the Correlation Function(DCF). Then, significant wave height was calculated through DCF waveform width. Feasibility of the method is verified. It worked under all-weather and all-day conditions with the advantages of high resolution and low cost, demonstrating significance for monitoring small and medium scale ocean states and physical phenomena.