Research On Wave Information Inversion Of Bacscatter In Wide-bandcoherent X-band Radar

The scope of human activities has extended from the land to the ocean as people continued progress and development. Many countries in the world have been exploiting and utilizing the rich marine resources and have created enormous wealth. Ocean monitoring system which can provide important support to the activities of States on the ocean has been widely studied. Compared with other ocean monitoring tools, X-band radar system for hydrological parameter measuring is characterized by flexible, efficient and low cost.This paper studies the traditional spectral analysis extraction method for hydrological parameter under non-coherent radar. With the method of generating random waves and sea face modulation mechanism in radar images, we succeeded to get the wave radar image sequence in specific parameter through computer simulation. Based on simulated image sequence, we obtained the inversed wave spectrum by using traditional hydrological parameter extracting algorithm, which has proved to be consistent with the input simulation spectrum.The traditional method of spectral analysis neglects the speed information measured by radar. This paper gets the relationship between wave orbital speed and parameters of the wave spectrum. In combination of relevant research overseas about wave Doppler information with the acquired IPIX radar data we have verified that there is a strong correlation between the two parts. Doppler velocity information and wave period come the first and significant wave height is the second.Wave height measurements based on SNR require calibration with correct buoy data. This paper has analyzed and verified algorithm proposed in 2014 by professor Gangeskar who has been engaged in X-band radar waves Information Retrieval which can calculated significant by using the shadowing modulation theory without calibration. The threshold for radar image binarization in the method above has greatest impact on inversed wave height. We obtained the gist and proposed a method to determine the value of threshold by analysis the IPIX radar measured data.Finally, in order to make wave detection system capable on a mobile platform such as a carrying boat, we have done preliminary research for shipborne wave information inversion and introduced compensation method for ship movement. Moreover this paper analysis the influence caused by vertical movement of a ship on radar sea images. Through the simulation we can draw a conclusion that the vertical moving for the platform in a ship will affect the signal to noise ratio of wave spectrum, thereby increasing the error of measured significant wave height.