Research On Significant Wave Height Inversion Method Based On GNSS-R

At present,GNSS-R(Global Navigation Satellite Systems Reflectometry)technology as a new type of remote sensing technology developed on the basis of navigation satellites around the world,has currently been applied to weather forecasting,environmental status monitoring,and traffic safety transportation.The satellite remote sensing signal have the characteristics of large coverage area,wide signal source and low resource consumption,many institutions and scholars at home and abroad have made significant technological progress in performing sea surface wind speed and direction inversion,sea ice thickness detection,sea oil spill monitoring and sea surface significant wave height inversion,and the use of this technology is of great significance to the monitoring of the marine environment and the prevention and mitigation of the ocean.This paper discussed and analyzed the main navigation satellites transmitting signals in the GNSS system,then investigate and analysis the current research status of the GNSS-R technology,the characteristics of the GNSS-R signal,the correlation function,and the GNSS-R sea wave height inversion geometric model in detail.On the basis of this research,further introduced the overall architecture and related module functions of the GNSS-R hardware receiver used in this paper,mainly including the simulation design indicators of the upward looking antenna and the downward looking antenna,and the design construction of the Doppler delay mapping receiver(DDMR).Secondly,studied the current model for measuring the significant wave height based on GNSS-R technology at the current stage.Elaborated the technical principle and related process of establishing the model through the derivative by the correlation function,the interference complex field and the signal-to-noise ratio of the reflected signal in detail.Further analysis and calculate of the time-delay Doppler spectrum,the correlation power value,and the signal-to-noise ratio SNR of the reflected signal,so as to proposed the method based on the combination of the correlation power of the reflected signal and the signal-to-noise ratio for data inversion,and given the specific route and calculation process of the scheme in detail.Finally,under the theoretical support of the completion of the above research,through the miniature marine environment power detector and Oceanpal receiver mounted on the Yukun teaching practice ship,employ and implement the experiment of inverse significant wave height measurement.The experimental route starts from Dalian to Taizhou,through the Bohai Sea and the Yellow Sea,the entire experiment took about four days and the effective recording time was more than thirty hours.After the experiment completed,processed the actual data collected by navigation to obtain the corresponding experimental results,analysis and compare the data calculated by the two models with the observation data of the nautical wave instrument,verify the advantages and feasibility of the inversion model proposed in this paper,which provides reference value and practical significance for subsequent research and application.