低密度校验码是一种能逼近Shannon容量限的渐进好码,在长码时其性能甚至超过了Turbo码。其译码采用了具有线性复杂度的和积算法,复杂度大大低于Turbo码,并且几乎所有错误都是可检的。这里着重介绍LDPC码软判决译码的基本思想,以及LDPC码的量化译码方案,提出了一种高效的量化译码实现方案。由于低密度校验码具有诸多优点,它在信息可靠传输中的良好应用前景已经引起世界各国学术界和IT业界的高度重视,成为当今信道编码领域最受瞩目的研究热点之一。
Low - Density Parity - Check (LDPC) codes are capacity approaching good error - correcting codes. By using low complexity sum - product algorithm, LDPC codes can get near Shannon bound decoding performance with almost all errors detectable. This paper discusses the principles of soft decoding and quantization decoding of LDPC codes. An effective quantization decoding implement is proposed. Due to its various advantages, LDPC codes have become one of the hotspot in the field of channel coding.