With the development of information technology and the progress of science and technology, broadband wireless communication is changing people's way of life. Traditional software radio communication algorithms can't meet high speed and efficient data processing requirements, and GPU parallel processing technology arises at the historic moment. Based on this, starting with GPU and CPU, the relationship between parallel and serial operation was studied. According to the characteristics of GPU with high performance, high bandwidth, high parallelism and programmable architecture, the principle of parallel Turbo algorithm in GPU is discussed. The turbo decoding algorithm is studied from both MAP and SOVA, and the total structure of the GPU decoder based on GPU and the subroutine thread distribution are proposed. And the result shows that GPU parallel processing technology based on the fine grained software radio communication algorithm, not only increases the granularity of fine-grained parallel particles, but also improves the operation speed. [ABSTRACT FROM AUTHOR]