基于GNSS-R的海面风速探测技术研究

Sea Surface Wind Speed Measurement Using GNSS Reflection Signal

该文利用数值仿真手段分析了全球导航卫星系统海面反射(GNSS-R)信号的时延相关功率曲线特征,讨论了风速、风向、GNSS卫星高度角、接收机平台高度和速度等因素对海面散射信号相关功率的影响,给出了GNSS-R海面风速的反演方法和技术流程,并进行了试验验证。结果表明,在中低风速条件(<20 m/s)下,GNSS-R测量的海面风速与实测风速的基本一致,说明GNSS-R探测海面风速的可行性以及该文给出的海面风速反演方法的正确性。当风速超过20 m/s时,由于受海浪谱模型的限制,其反演的结果明显低于实测风速。最后,根据试验结果,初步给出了GNSS-R测量海面风速的修正模型。

This paper introduces the mechanism of sea surface wind measurement using Global Navigation Satellite System Reflection（GNSS-R） signal and sea surface scattered signal theoretical model.Then the delay waveform of sea surface scattered signal is analyzed through numerical integration,and the influence of wind speed,wind direction,GNSS satellite elevation angle,receiver height and receiver speed on this delay waveform is discussed in detail.Based on the above analysis,the algorithm of GNSS-R sea surface wind retrieval is proposed.In order to validate the mechanism of GNSS-R measuring sea surface wind and the accuracy of this algorithm,Hurricane Dennis is used to test.The result shows that GNSS-R wind speed is generally consistent with the observational data for the low-moderate wind speed（20 m/s） and is less than the observational data for high wind speed（20 m/s）.Finally,the correction model of GNSS-R wind speed is initially proposed on the basis of the experimental results.