The Research Of Underwater Source Detection Using Laser Based On CCD

As a kind of illuminant with high brightness and high collimation, laser is widely used in active homodyne fields. A laser-based sonar detection,combined with laser detection and sonar technology ,has received universal attention,and been developed rapidly.The major mode applied to laser-based sonar detection is single-point active homodyne using the small facula,however,the mode applied in this paper will enlarge the area for active homodyne, and use the big facula.At the same time,Change Coupled Device (CCD) will be used to received laser,which has the better pricision and extent.Finally,the method of digital image processing will be used to process the image received by CCD to detect the underwater source.Principles and development situation of laser-based sonar detection are described. One-dimensional model for the surface perturbation is derived, and the dispersion relations is infered;simultaneity ,the relationships between the deepness of the underwater source and dispersion relations is debated in this paper;the relationships between particle vibration velocity,displacement on water interface and underwater target radilted signal is gived.The simulation of the random rough surface:in this paper,we use Monte Carlo method to simulate the one-dimensional random sea surface.The resultant surface perturbations result in that the reflected laser engender dispersion. CCD is used to receive the reflected laser that will form the image and be stored,and process that image using the method of the 2D-fft,so that space-distributing of the reflected laser can be converted to frequency domain.Therefore,we can acquire the information of the frequence by the variations of the luminous flux.