摘要
介绍了迭代译码器实现需要考虑的几个问题,以及在实际应用中迭代译码器需要的先决条件——软值计算的几种方法,给出相应算法的实现,并在最后对这几种实现方法进行了性能和资源上的比较。
It is necessary for soft output decoding algorithm to have the QAM signal demapped into corresponding soft output. Implementation constraints on iterative decoders are listed. The method of demapping QAM signal to LLR （log likelihood Ratio） criterion, which is needed in advance, is introduced. A kind of metric algorithm is presented. Finally, the implementation methods are compared in terms of performance and resource.
出处
《电视技术》
北大核心
2006年第9期24-27,共4页
Video Engineering
关键词
迭代译码器
对数似然比
正交幅度调制
iterative decoder
LLR（log-likelihood ratio）
QAM（quadrature amplitude modulation）
