The Simulation Design On Digital Intermediate Frequency Receiver For WCDMA And TD-SCDMA Based On Software Radio

The rapid development of the third generation of mobile communication has formed the situation in which many kinds of communication system have coexisted. Three major standards have appeared in the world, they are separately WCDMA of Europe, CDMA2000 of North American and TD-SCDMA of China. Because standard of every system is independent each other, they are difficult to intercommunion. They have brought enormous obstacle to the roam of a portable radiotelephone in whole world. As new system and standard of communication are proposed constantly, the life cycle of communication products is shortened, the expense of development is rose, the traditional communication systems are already very difficult to suit.SDR (Software Defined Radio) is a kind of new technology of communication that it puts forward in recent years. It defines that on the simple and general hardware platform, varies radio applications can be implemented by using the software which can be updated and reconfigured. SDR can make the wireless communication system have a good flexibility and generality. Also, the interlinkage and update of the system will be very convenient. The software radio is a best scheme that it can realize compatibility of different systems.In this case, this text designs an intermediate frequency receiver for WCDMA and TD-SCDMA based on software radio, to research the software radio's application in the 3G system. The receiver focuses on the digital structure of wide-IF, and the signal processing units such as A/D Converter DDC digital demodulation and so on. The design and application of AD6654 are fully discussed in this part. Finally, the system simulation of the receiver is carried on with System View, shows that the software radio system has the flexibility, openness and compatibility in processing the multimode signal. The study of the software radio is a kind of exploration that the software radio will concretely realize. The study will establish the foundation for realizing many modes receiver in the future too.