Turbo码不同译码算法中的量化性能分析

针对Turbo码的不同译码方法，提出了不同情况下的中间变量的量化方式。在已完成接收比特、附加信息和输出似然值的量化情况下，着重讨论了不同译参政方式的中间变量的量化范围、量化级别和量化方法对译码性能的影响。仿真结果表明，对于改进的Turbo码的译码算法（LOG-MAP，MAX-LOG-MAP，SOVA），中间变量的量化可以不采用非均匀量化，而且中间变量量化的级别也可以大大减小，不仅降低译码复杂度，而且减少了硬件实现时所需要的存储空间。

Analyzing of quantification performance on different decoding algorithm of Turbo codes

The paper mainly presents the different quantification patterns of the mid variables of different decoding algorithms of Turbo codes based on their distributing characteristcs. Great effort is made to discuss the effect of the quantification bound, quantification level and the method of the mid variables on the performance of turbo decdoing with different decoding algorithms. The simulation result shows that, for the improved decoding algorithms, such as LOG MAP, MAX LOG MAP, SOVA, etc, the quantification pattern of mid variables may not be non uniform quantification. At the same time, the quantification levels of the mid variables can be reduced greatly. So with the above decoding algorithms, we can not only reduce the complexity of decoding, but also make the storing space decrease during implementation with hardware. All of this provides an explicit base for the engineering application.