【摘要】 在介绍 L DPC (L ow Density Parity Code)低密度校验码的基本原理的基础上 ,针对任意离散无记忆信道的传输 ,从两个方面对其结构进行了改进。这种改进的 L DPC码是定义在有限域 GF(q)上的非正则 L DPC码 ,较之正则 L DPC码具有更好的性能。采用改进的非正则 L DPC码 ,经过最大似然概率译码 ,能够实现以任意逼近任何离散无记忆信道容量的速率的可靠通信。同时 ,讨论了对应于这种码结构的实际的迭代译码方法 ,并简单介绍了这种改进的非正则 L DPC码在OFDM系统、压缩图像传输等方面的应用。更多还原

【Abstract】 On the basis of introducing the basis principle of LDPC code, we mend the structure from two aspects about transmission over arbitrary discrete memoryless channels. This kind of LDPC code is an irregular LDPC code defined over the field GF(q) and has better performance in comparison with other regular LDPC codes. We consider that using the irregular LDPC code, under maximumlikelihood decoding, is capable of reliable communication at rates arbitrarily close to the capacity of any discrete memoryless channel. Simultaneously, we discuss practical iterative decoding of this code structure and introduce its application simply on OFDM system and compressing image transmission system.更多还原