准循环LDPC码高速译码实现方法

Implementation for High Speed Decoder of QC-LDPC Code

20世纪60年代初,香农的学生Gallager在他的博士毕业论文中首次提出了LDPC码的概念和完整的译码方法,但是直到上世纪末期,随着LDPC码译码理论的进步和计算机技术的发展,LDPC码才以其优良的误码性能成为人们研究的焦点。目前LDPC码正向着高速高增益的方向发展。文中针对目前对高速LDPC码译码技术的迫切需求,以CCSDS标准近地通信(8176,7154)LDPC码为研究对象,在传统高速译码实现方案所用资源不变的前提下,利用该码校验矩阵中1的排列特点,仅通过改变水平运算过程中数据处理的流程,来增大水平运算和垂直运算之间的复用程度,从而达到大大提高译码速度的目的。采用文中给出的方案对CCSDS近地通信标准(8176,7154)LDPC码进行译码,每个水平迭代周期可以减少近10%的运算时间。该方案同样适用于其他的QC-LDPC码。

At the beginning of 60＂s of last century, Gallager, the student of Shannon,issued the concept and a whole set of method for de- coding of LDPC code at the first time in the world. But the LDPC code had not been on the focus of the research with its super perform- ante until the end of the last century, for the improvement of the decoding theory and the development of the computer technology. Nowa- days,the LDPC code is developing aiming at high speed and super performance. !t studies the （8176,7154） LDPC code in the CCSDS near earth standard,aiming at the exigent demand of the high speed LDPC decoder. This method uses the character of the ＂ 1＂ s to enhance the overlapped degree to improve the speed significantly of the decoder by the only change of the processing order of the CNU without any resource increase comparing with the traditional method. The decoder of the CCSDS near earth standard （8176,7154 ） LDPC code can save computation 10% by this method. And this implementation can also be used to other QC-LDPC codes.