The Research And Realization Of Coding And Mutiplexing Of TD-SCDMA's Channel

Since 1990s, the mobile communication technology and the Internet technology development enormously influence people's life, the study and the work, two unions were the information industries development ways that must be taken. In two unions products ,the most outstanding representative is the third generation mobile communication (3G).which takes the wide band, the multimedia service as well as seamless turns on as the symbol .3G mobile communication system mainstream standard consist of European the WCDMA system, North America's cdma2000 system and our country's TD-SCDMA system.TD-SCDMA standard is certain characteristic the 3G system standed which is proposed according to researching for many years by the.China's Ministry of Information Industry telecommunications Science and Technology Research Institute (Datang Telecom Group),under being supported by the Ministry of Information Industry in the country.In November of 1999, TD-SCDMA, became one of the wireless transmission mainstream standard of 3G ITU approval.The paper analyzed each link of the transport channel coding and multiplexing in the TD-SCDMA system according to the 3gPPRelease4 agreement.The Simulink MATLAB provided software package carries on the entire flow the dynamic simulation.And analyzed the question which appeared in the actual movement.This paper has carriedon comparatively deep researchs to several key technologies of the transmitting channel of TD-SCDMA.Based on MALTAB simulation method designed transmission system under the non-disturbance situation advance a set of comparatively integrated system design theme. In the meanwhile, a feasible method of decoding and demutiplexing is proposed with coding. A simulation of coding and multiplexing and decoding and demutiplexing for transmitting channel based on Simulink of MATLAB is implemented .Here are several key technologies, such as convolutional coding and decoding, Turbo coding and decoding interleaving and deinterleaving,ratematching and deratematching etc.Estimated question which appearedin the actual movementBased on the simulation of the ideal channel, In order to reflect the signal in typical channel transmission effect,channel is also modeled for three other types :additive white Gaussian noise channel ,muti-path Rayleigh fading channel and Rician fading channel.Emphasis is put on the analysis of the error rate of the system outdoors.indoors under the above three channels.And the question which appeared in the actual movement, .is analyzed.In the final, M-QAM modulation is proposed to be uses in the system, and comparaed with QPSK modulation in performance.The coding system is improved.The result is the 8-QAM modulation has the lowest error rate in the system.