On the Hamming Weight Distribution of Subsequences of Pseudorandom Sequences

Mahyar Shirvanimoghaddam

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arXiv · 2107.05156

On the Hamming Weight Distribution of Subsequences of Pseudorandom Sequences

Mahyar Shirvanimoghaddam

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Abstract

In this paper, we characterize the average Hamming weight distribution of subsequences of maximum-length sequences ($m$-sequences). In particular, we consider all possible $m$-sequences of dimension $k$ and find the average number of subsequences of length $n$ that have a Hamming weight $t$. To do so, we first characterize the Hamming weight distribution of the average dual code and use the MacWilliams identity to find the average Hamming weight distribution of subsequences of $m$-sequences. We further find a lower bound on the minimum Hamming weight of the subsequences and show that there always exists a primitive polynomial to generate an $m$-sequence to meet this bound. We show via simulations that when a proper primitive polynomial is chosen, subsequences of the $m$-sequence can form a good rateless code that can meet the normal approximation benchmark.

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Mahyar Shirvanimoghaddam. 2021-07-12. On the Hamming Weight Distribution of Subsequences of Pseudorandom Sequences. https://arxiv.org/abs/2107.05156

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