In order to get the edge message of a target, a laser scanning system was established. The laser scanning system steers a
beam of laser energy which is dithered in two directions to scan the surface of the object. A laser energy detector detects
laser energy reflected from the target. The reflected information is filtered to distinguish dither frequencies for signal in
both directions. The signals are independently analyzed to determine the edge of the target by detecting the change of
reflected laser energy.
In order to get the fantastic point of echo signal, wavelet transform is used. Based on invariability of the quality factor of
wavelet transform, combined with proper wavelet group, this paper discusses the application of wavelet transform for the
detection of echo signal. On the basis of algorithm analysis, from aspects of detecting principle, detecting steps and
computer emulation, the authors expatiate how to use wavelet transform to find the fantastic point of echo signal, finally
to find the edge of the target being detected. Wavelet transform has the ability of denoting local signal characteristics, so
it is fit to analyzing instantaneous and fantastic phenomena and can lay out signal components. The method in this paper
will supply an algorithm gist and a reference for signal processing for the detection of edge message of target. The results are demonstrated by using Matlab programme. By the measure, the noise can be eliminated, and effective signals can be picked up. When applying the wavelet transform to experimentation, a satisfactory result was obtained. When using this method, the ability of edge detection can be greatly improved.