Study of Decoding Implementation of Turbo Codes in Third Generation Mobile Communication

On the basis of analysis on TURBO input quantification, this paper offers the electrocircuits and iteration electro-circuits for TURBO coding in the 3GPP, with existing MAP algorithm combined, thus improves the transmission rate of the 3GPP. The recently proposed TURBO codes are applied to multilevel modulation, then to multistage decoding. Based on the information theory, the method of designing rates and interleaving lengths of TURBO codes is proposed, which makes the lower levels codes have higher correct error capacities and the higher levels codes have higher transmission capacities. The coding of TURBO codes in the 3GPP is also analyzed and the delay problem and the scale problem of FPGA are discussed. The electro-circuit performs well in coding, which meets the gain demands of the 3GPP.