| The direct-sequence spread-spectrum (DS/SS) technique has been applied for mobile communication, telemetry and orinentetion, radar system since it offers many advantages including anti-eavesdropping, anti-interference, multiple access.And it is also the most common means of spread-spectrum. In the DS/SS system, it is the research emphasis to acquire and keep the synchronization between the local code signal and the received signal.On the other hand, wavelet theory has become more and more perfect since the eighties of the twentieth century, and gained great development in many field with its popularization. Wavelet theory provides powerful instrument for signal process, and there are practical application in common filtering noise reduction and singularity detection.As a new multiresolution means, wavelet can effectively distill the message from signal and can .detect the transient signal rapidly and exactly. So this paper study heavy by combining the wavelet transform with spread-spectrum code detection and acquisition of the synchronization technology.This paper study the PN code acquisition system based on the characteristic of wavelet multiresolution detection by using the advantage of wavelet transform in transient signal detection and aiming at the characteristic of acquired modulated signal and non-acquired white Gaussian noise signal. And calculate the filter coefficient of quadratic perpendicular B-spline wavelet according as wavelet analysis theory and B-spline function characteristic. At the same time , compare the result of detection using B-spline wavelet with that of Battle-Lemarie wavelet ,and the result indicate that the B-spline wavelet is much better in this system. Analysize the performance of this acquisition system and discuss the work flow and calculate some important parameters such as average acquisition time and so on. The MATLAB simulation results show that this method havetheory value and applied value.
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