The Design And Implementation Of GSM Listener

With the 3G licenses were issued in various countries, we have entered the 3G era. 3G system has a higher data transmission rate and channel utilization, the evolution of 2G to 3G is indisputable. However, at present, GSM is still the world's most widely used mobile communication system, and also the one with the largest business volume. In addition, even in Europe, the most active area in promoting the 3G services, its 3G system's coverage still can not be compared to GSM's. In the area that the 3G system hasn't covered, in order to meet the needs of accessing to 3G, family-oriented pico-WCDMA base stations come into being, these base stations target at GSM/WCDMA dual-mode phones. As described in this thesis, GSM Listener is a component of such pico-WCDMA base stations, and it can provide faster switch from WCDMA to GSM for GSM/WCDMA dual-mode mobile phones.This thesis first gives an overview of the research and working background. Next, in chapterⅡthe development environment and platforms are introduced.The third chapter describes the basic knowledge of the GSM system, including system network structure, channels, time slot & frame structure, modulation and channel coding.ChapterⅣfirst introduces the working modes of GSM Listener, and then gives the overall logical structure of the Listener.ChapterⅤis about the design of the synchronization process, which is the key chapter of this thesis.ChapterⅥis about the design of the demodulation and decoding process, including the decoding algorithm analysis for shortened Fire code.