The implementation of turbo decoder on DSP in W-CDMA system

This paper describes the design and implementation of turbo decoder which has been selected for 3G mobile systems on TMS320C6201 DSP developed by Texas Instruments (TI) in 1998. With the incomparable operating speed, which is 200 MHz (5-ns cycle time), TMS320C6201 DSP can achieve the performance of up to 1600 million instructions per second (MIPS) and consequently has gained more and more popularity in many applications. In this paper a turbo decoder is implemented on the TMS320C6201 evaluation module(EVM) board with the code rate 1/3. To every step of the algorithm, we discussed the optimized C code and the minimum cycle time of CPU (best situation of the theory), and get pleasant decoding speed.