極化碼在快閃記憶體中更正能力提升之主動式通道調整策略

Proactive Channel Adjustment to Improve Polar Code Capability for Flash Storage Devices

徐堃程(Kun-Cheng Hsu)

指導教授 ： 郭大維

共同指導教授 ： 張原豪

國立臺灣大學/電機資訊學院/資訊工程學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201701566

摘要

無資料

關鍵字

儲存系統 ； 可靠性 ； 極化碼 ； 通道調整 ； 超大規模快閃記憶體

並列摘要

Low-density parity-check (LDPC) codes have made a great success on correcting errors in flash storage devices, but its hardware cost and error correction time keeps increasing as the error rate of flash memory keeps increasing. To improve the lifetime of devices, researchers are seeking alternative methods. Fortunately, with the low encoding/ decoding complexity and the high error correction capability, polar code with the support of list-decoding and cyclic redundancy check can outperform LDPC code in the area of data communication. Thus, it also draws a lot of attentions on how to adopt and enable polar codes in storage applications. However, the code construction and encoding length limitation issues obstruct the adoption of polar codes in flash storage devices. To enable polar codes in flash storage devices, we propose a proactive channel adjustment design to extend the effective time of a code construction to improve the error correction capability of polar codes. This design pro-actively tunes the quality of the desirable flash cells to maintain the correctness of the code construction and relax the constraint of encoding
length limitation. A series of experiments was conducted to evaluate the efficacy of the proposed design. It shows that the proposed design can effectively improve the error correction capability of polar codes in flash storage devices.

並列關鍵字

storage system ； reliability ； polar code ； channel adjustment ； ultra-scale flash memory

參考文獻

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