3 research outputs found
Write-Once-Memory Codes by Source Polarization
We propose a new Write-Once-Memory (WOM) coding scheme based on source
polarization. By applying a source polarization transformation on the
to-be-determined codeword, the proposed WOM coding scheme encodes information
into the bits in the high-entropy set. We prove in this paper that the proposed
WOM codes are capacity-achieving. WOM codes have found many applications in
modern data storage systems, such as flash memories.Comment: 5 pages, Proceedings of the International Conference on Computing,
Networking and Communications (ICNC 2015), Anaheim, California, USA, February
16-19, 201
Asymmetric Error Correction and Flash-Memory Rewriting using Polar Codes
We propose efficient coding schemes for two communication settings: 1.
asymmetric channels, and 2. channels with an informed encoder. These settings
are important in non-volatile memories, as well as optical and broadcast
communication. The schemes are based on non-linear polar codes, and they build
on and improve recent work on these settings. In asymmetric channels, we tackle
the exponential storage requirement of previously known schemes, that resulted
from the use of large Boolean functions. We propose an improved scheme, that
achieves the capacity of asymmetric channels with polynomial computational
complexity and storage requirement.
The proposed non-linear scheme is then generalized to the setting of channel
coding with an informed encoder, using a multicoding technique. We consider
specific instances of the scheme for flash memories, that incorporate
error-correction capabilities together with rewriting. Since the considered
codes are non-linear, they eliminate the requirement of previously known
schemes (called polar write-once-memory codes) for shared randomness between
the encoder and the decoder. Finally, we mention that the multicoding scheme is
also useful for broadcast communication in Marton's region, improving upon
previous schemes for this setting.Comment: Submitted to IEEE Transactions on Information Theory. Partially
presented at ISIT 201