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An illustration of the first model with gt(v) = N (0, σ) and ht(v) = N (1 − t, σ).

An illustration of the first model with gt(v) = N (0, σ) and ht(v) = N (1 − t, σ).

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This paper presents a practical writing/reading scheme in nonvolatile memories, called balanced modulation, for minimizing the asymmetric component of errors. The main idea is to encode data using a balanced error-correcting code. When reading information from a block, it adjusts the reading threshold such that the resulting word is also balanced o...

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... two trends. First, due to cell-level drift, the difference between the means of g t (v) and h t (v) becomes smaller. Second, due to the existence of different types of noise and disturbance, their variances increases over time. To study the performance of balanced modulation, we consider both of the effects separately in some simple scenarios. Fig. 5. We assume that the fixed threshold is v f = 1 2 , which satisfies g 0 (v f ) = h 0 (v f ). In the above example, the cell-level distribution correspond- ing to bit '1' drifts but its variance does not change. We ...

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Citations

... The detector resilience to unknown mismatch by drift can be improved in various ways, for example, by employing coding techniques. Balanced codes [6,7,8,9] and composition check codes [10,11], in conjunction with Slepian's optimal detection [12] offer excellent resilience in the face of channel mismatch on a block of symbols basis. These coding and signal processing techniques are often considered too expensive in terms of code redundancy and hardware, in particular when high-speed applications are considered. ...
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... To illustrate, consider the situation in Fig. 7(a). If we set L max = 10, then the received sequence is padded with invalid symbol values, resulting in a vector of [0, 1, 0, 0, 0, 1, 0, 0, 1, −1] that has length 10, and the output codeword boundary vector is γ = [2,6,9,11,11]. ...
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