Reduction of Error-Trellises for Tail-Biting Convolutional Codes Using Shifted Error-Subsequences

Masato Tajima; Koji Okino; Tatsuto Murayama

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arXiv · 1401.2496

Reduction of Error-Trellises for Tail-Biting Convolutional Codes Using Shifted Error-Subsequences

Masato Tajima·Koji Okino·Tatsuto Murayama

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Abstract

In this paper, we discuss the reduction of error-trellises for tail-biting convolutional codes. In the case where some column of a parity-check matrix has a monomial factor (with indeterminate D), we show that the associated tail-biting error-trellis can be reduced by cyclically shifting the corresponding error-subsequence by l (the power of D) time units. We see that the resulting reduced error-trellis is again tail-biting. Moreover, we show that reduction is also possible using backward-shifted error-subsequences.

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Masato Tajima, Koji Okino, Tatsuto Murayama. 2014-01-11. Reduction of Error-Trellises for Tail-Biting Convolutional Codes Using Shifted Error-Subsequences. https://arxiv.org/abs/1401.2496

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