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arXiv · 1701.07521

Floor Scale Modulo Lifting for QC-LDPC codes

Nikita Polyanskii·Vasiliy Usatyuk·Ilya Vorobyev
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Abstract

In the given paper we present a novel approach for constructing a QC-LDPC code of smaller length by lifting a given QC-LDPC code. The proposed method can be considered as a generalization of floor lifting. Also we prove several probabilistic statements concerning a theoretical improvement of the method with respect to the number of small cycles. Making some offline calculation of scale parameter it is possible to construct a sequence of QC-LDPC codes with different circulant sizes generated from a single exponent matrix using only floor and scale operations. The only parameter we store in memory is a constant needed for scaling.

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Nikita Polyanskii, Vasiliy Usatyuk, Ilya Vorobyev. 2017-02-04. Floor Scale Modulo Lifting for QC-LDPC codes. https://arxiv.org/abs/1701.07521

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