Research And Design Of X-band Marine Radar Image Pre-processor

In the process of using marine radar to measure wave, there is always some interference。The most common ones of these interference are the same frequency interference, solid-target interference and rain interference. The existence of these interference will reduce the quality of collected radar images, thus affecting the accuracy of waves parameters which extracted from radar images. In order to obtain accurate wave information, radar images should be pre-processed. The purpose of this study is how to deal with the same frequency interference, solid-target interference and rain interference, to improve the quality of radar images, thereby ensuring the accuracy of wave information.After the research on the same frequency interference, solid-target interference and rain interference, this paper firstly used several different methods to process each type of these interference, and gived analysises and evaluation of the effects for each treatment, and then selected the most appropriate methods for each interference, and finally integrated these methods for dealing with the three kinds of interference to be a image pre-processing software, using VisualC++6.0 programming tool,based on WindowsXP system.During the simulation of interference processing by the use of Matlab, we found that the improved median filtering method can filter out the same frequency interference, the mean and the difference coefficient method can effectively distinguish between rain image and non-rain images, the improved median filtering method cannot totally remove noise of rainfall image, the threshold - distance method can effectively remove the solid targets noise. After integrating the methods on the above to the image pre-processing software, its effect of pretreatment are roughly the same with the simulation results. This illustrates the preprocessing method proposed in this paper is feasible.