Wireless Spread Spectrum Digital If Communication System Design And Implementation

The software defined radio is a new architecture of realization of wireless communication system. Its main idea always makes the wideband A/D and D/A converter of the system nearer to RF module, and makes more software modules realize wireless function. At the same time, it can follow the change with the development of new communication technology for the modularizations. Except that the new design idea, some new technologies are invented, for example, spread frequency, which has some specific characteristics, such as high resistance to interference, low bit error rate, high resistance to multi-path interference. CDMA, different users which have the common used and same frequency can make them communicate one another. These new design ideas and new technologies are melted into the wireless data transmission system we designed.In this dissertation, there are three main parts which are studied, the first is the design and implementation of Reed-Solomon code, the second is the hardware design of the wireless data transmission system based on intermediate frequency. The last is the decoding of MP3, audio part of the mobile multimedia system. And the primary works in this paper are presented as follows:1. Introduced the background of this dissertation, the development of common used RS encoding algorithms, channel coding and mobile multimedia system.2. Introduced some basic knowledge about Reed-Solomon code, and discussed the theories and the design of encoding and decoding of Reed-Solomon code in detail. Implemented RS (255,239) encoder/decoder in Spartan-3 series of FPGA from Xilinx Company. Furthermore, applied it in our wireless data transmission system.3. Detailed the system scheme and the hardware design scheme of the wireless data transmission system, selected the proper chips, detailed the circuitry design and realization each part of the system. At the same time, introduced the design and the making of print circuit board (PCB), and the making crafts for PCB are in our country. Detailed the basic and main principles about the design course of PCB are cautioned. 4. Detailed research the decoding of MP3, audio part in mobile multimedia system. Introduced the framework of the frame, the architecture and principle of encoder and decoder.5. Summarized and concluded the whole dissertation, pointed out future research issues and possible research directions.