Upper Bounds of Interference Alignment Degree of Freedom

Feng Ouyang

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arXiv · 1510.08901

Upper Bounds of Interference Alignment Degree of Freedom

Feng Ouyang

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Abstract

Interference alignment allows multiple users to share the same frequency and time resource in a wireless communications system. At present, two performance bounds, in terms of degree of freedom, have been proposed. One is for infinite-dimension extension and the other is for MIMO systems. This paper provides an understanding of the MIMO bound by examining its proofs and shows that it does not apply to a more practical case: MIMO-OFDM. Several approaches are proposed in searching for DoF bounds for systems such as finite-dimension time extension and MIMO-OFDM systems.

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Feng Ouyang. 2015-10-29. Upper Bounds of Interference Alignment Degree of Freedom. https://arxiv.org/abs/1510.08901

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