多层光盘调制码的优化

Optimization of modulation code for a multilayer disc

为达到光盘容量的最大化,基于多层光盘,对现有的调制码进行了优化,并对优化后可能出现的超出jitter允差问题和锁相环(PLL)时钟同步问题进行了分析并给予解决。提出了一种有别于传统的多层混合时钟同步信号获取方法,用以满足PLL稳定工作的要求,并用数理方法验证了这种方法的有效性。最后选用d=4和k=10～15作为多层并行读写光盘调制码的参数,最大码率时可提高光盘的线密度15%～23%。

The current modulation code for a multilayer parallelaccess disc was optimized to increase the storage density. Two problems which affect the optimization are the acceptable jitter and the phaselocked loop (PLL) synchronization process. A novel method is proposed for procuring the clock information for a multilayer disc, which satisfies the PLL requirements. The effectiveness of the method was proven using probability theory. The optimized PLL parameters for the multilayer disc are d=4 and k=1015 which improve the track density by 15%23%.