Research And Accomplishment Of The Base-band Signal Generator Based On TD-SCDMA

TD-SCDMA is one of three kinds of standards of the 3^rd generation mobile telecommunications system. How to get perfect and standard base-band signal is a pivotal problem in the course of system researching and testing. This paper designs a base-band signal generator through the analysis of 3GPP protocol.First, this paper introduces some related basic concepts and developing situation of TD-SCDMA. Then, on the basis of physical layer specification in 3GPP 1.28Mcps TDD, the instruct and funcation of physical channel and transport channel is anylyzed, the flow chart of TD-SCDMA baseband signal is confirmed, the arithmetic of every module is introduced in detail, including CRC coding, convolutional coding, Turbo coding, interleaveing, rate matching, spreading, scrambling and the design of pulse-shaping filter and so on. At last, according to the channel coding and multiplexing of every transport channel, the flow scheme is designed.