Modem Based On The V.34 Protocol Analysis And Research

ITU-T V.34 RECOMMENDATION is mainly applied in the high-speed Modem in the modern communication. Because of the key technologies applied in the recommendation, the rate of the data communication is greatly enhanced. The V.34 recommendation mainly rules the technologies of coding and decoding. This paper according to the V.34 recommendation analyses the key technologies and algorithms, such as shell mapping, rotationally invariant code, 4-dimensional Trellis-coded modulation (TCM), pre-coding, and viterbi decoding algorithm etc, and presents some concrete application plans. Also, this paper introduces the modulating and demodulating in order to ensure the integrality of the system. The first chapter of this paper introduces the function and history of the Modem; the 2nd chapter discusses the theoretical background of the technologies; the 3rd and 4th chapters presents the concrete application plans of the technologies of the V.34 recommendation; the 5th chapter discusses the hardware plantform required by our system; the 6th chapter suggests some mendings to the algorithm and software application. In the end, because of the advancement of the digital adaptive equalization, the Modem based on V.34 will not be confined to the data transmition bandwidth of 2400Hz of the telephone network, which now has been expanded to 3100Hz. And conbined with the application of many technologies,the Modem enhances the maximum transmission rate to 33.6kbit/s, which is very close to the limit of Shannon—35kbit/s.