Number Simulation Of Getting Wave Information Based On X-band Radar

The ocean which is about two thirds of the Earth is so important to human's life.It not only offers the protein that people need,but also contains huge numbers of resources.Meanwhile,it affects the climate and our life a lot,especially wave,storm tide and tsunami.It becomes so urgent to detect and measure the ocean waves.In recent years,considerable interest has been shown in using the X-band radar to detect the ocean waves among so many methods,which is economic,convenient and can perform well all day long. Although the processes which cause a radar return from water waves are still not fully understood, a method to get the information from the clutter has been found.It needs experiment to perform the method and improve it Number simulation could operate the method and help understand the wave returning from water waves before the time wasting and material using ocean experiment.This paper not only introduces the way to get the clutter from the sea images and the method to get information from clutter,but also describes the whole simulation.First simulate the wave field using PM spectrum basing on the linear wave model,change the parameters to obtain different wave fields.The area is 2550*2550 m~2.The resolution is 10m.We get 32 consecutive images representing 80s of data.Then the clutter images could be obtained from the wave field series images.The longer waves modulate the short Bragg scattering waves which can be imaged by the radar.It is a sum effect that contains the geometrical effects of shadowing and tilt,Hydrodynamic modulation,and wind modulation.Among these effects,shadowing and tilt are more important.Basing on them clutter images are obtained.The blind area of X-band radar and the FFT needing are considerated during the process.Finally mean wave direction,wave period can be obtained from the clutter images.It needs 3DFFT,filter,integral and modulation transfer function(MTF).By comparison of the input and output number,the wave getting method is proved,and the modulation is known well.