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

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 critical flash cells to maintain the correctness of the code construction and relax the constraint of the encoding length limitation, so that polar codes can be enabled in flash storage devices. A series of experiments demonstrates that the proposed design can effectively improve the error correction capability of polar codes in flash storage devices.