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arXiv · 1811.03832

Information Theoretic Bounds Based Channel Quantization Design for Emerging Memories

Abstract

Channel output quantization plays a vital role in high-speed emerging memories such as the spin-torque transfer magnetic random access memory (STT-MRAM), where high-precision analog-to-digital converters (ADCs) are not applicable. In this paper, we investigate the design of the 1-bit quantizer which is highly suitable for practical applications. We first propose a quantized channel model for STT-MRAM. We then analyze various information theoretic bounds for the quantized channel, including the channel capacity, cutoff rate, and the Polyanskiy-Poor-Verdú (PPV) finite-length performance bound. By using these channel measurements as criteria, we design and optimize the 1-bit quantizer numerically for the STT-MRAM channel. Simulation results show that the proposed quantizers significantly outperform the conventional minimum mean-squared error (MMSE) based Lloyd-Max quantizer, and can approach the performance of the 1-bit quantizer optimized by error rate simulations.

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BibTeXRIS

Zhen Mei, Kui Cai, Long Shi. 2018-11-09. Information Theoretic Bounds Based Channel Quantization Design for Emerging Memories. https://doi.org/10.1109/itw.2018.8613421

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