IRA码在全息存储系统中的应用研究

Irregular Repeat Accumulate Codes for Holographic Data Storage System

前向纠错码(FEC)是全息存储系统提高系统容量的一项关键技术,不规则重复累积码是接近Shannon限且具有线性时间编译码算法的好码。首先研究了全息存储信道,提出了x平方律分布模型与不对称高斯分布模型;并将高性能的IRA码应用于全息存储系统,并进行了仿真研究。仿真结果表明:在全息存储系统中,IRA码的性能优于RS码等传统码,而且x平方律信道下的性能优于高斯信道。

Forward error correction codes have become a practical solution in improving capacity of holographic memory system. Irregular repeat accumulate （IRA） codes have good performance very closed to Shannon limit. IRA code has linear-time encoding and decoding algorithms. In this paper, firstly we study holographic memory channels and present two kinds of models： Chi-square distribution and Gaussian distribution model. Then we apply IRA codes to the holographic memory system. Simulation results show that the performance of IRA outperforms traditional RS codes in holographic memory system. The decoder based on Chi-square also has better performance than that of the decoder based on Gaussian noise assumptions.