Technology Of Synchronization In CDMA20001X/EVDO

Synchronization technology is a key processing technology of receiver in spreading mobile communication system. Synchronization technology which applied in scanner of CDMA20001X/EVDO system was mainly discussed in this paper. In scanner, the requirement of synchronization is higher and more functions are needed. This paper studied the synchronization and related processing technologies basing on multi base stations in scanners. The scheme meets the requirements of the performance and functions in the special hardware environment.This paper introduces the transmitter characters of CDMA20001X and its revolution version (CDMA2000EVDO). By deeply understanding of the spreading signal, some scheme and arithmetic of synchronization processing are designed for acquisition. In the scheme, the synchronization mainly divided into two parts, the initial synchronization and the related processing. Initial synchronization means to acquire the Pseudo Noise codes. According to the characters of the CDMA2000 system and the requirement of the scanner, a scheme combining the FFT based fast convolution and PMF-FFT arithmetic is designed to research signals from multi base stations in the air. For the related processing, frequency error estimation and compensation, frame synchronization, code phrase acquisition and all that are also included in this paper.As to detect and process the signals from multi base stations in the scanner, complication of realization and the system resource is need to be taken into account. A Digital Auto Gain Control technology which belonged to the software radio technologies is introduced in this paper. The technology can effectively control the magnitude of the signal and clip the length of the data, so the complication can be reduced but the performance of demodulation is kept well. A new Digital Auto Gain Control technology is designed on this paper. In the scanner project, the main work in this paper is arithmetic design and simulation, the performance and the complication of realization is taken into account. The above-mentioned scheme and arithmetic are simulated and some optimized parameters and values are obtained. The main tool for simulation is MATLAB. According to the simulation result, the scheme and arithmetic in this paper have good performance and complication. The technologies introduced in this paper have realized by hardware and applied for some patents.