Research On The Block Turbo Code For WiMAX Wireless Mobile System

Block Turbo Code (BTC) is one of the optional channel coding schemes forIEEE802.16e-2005. BTC has flexible frame size and code rate. It can achievehigh efficiency coding.It is suitable for communications under poorconditions. This paper presents the basic structure of BTC coder and decoderand its application in IEEE802.16e-2005WiMAX wireless mobile system, givenout the simulation result and comparison between different configure.In addition, particularly in response to the existing code division Turbodecoding algorithm is too complicated, in reference to a great deal ofinformation, this paper, packet decoding Turbo codes to improve the program,which is a major innovation in this article and highlight the use of constantpiecewise function approximation method,using three alternative approximateconstant correction function,the more sub-function approximation in thecorrection function, through the look-up table to choose the appropriateparameters, in a slight increase in decoding complexity, the decodingincreases performance, we will call this decoding to improve the program:Two-Constant-Log-MAP, the purpose is to make sub-Turbo truly WiMAXcommunication systems into a simple algorithm, strong anti-interferenceability of error-correcting codes.