Proximity Factors of Lattice Reduction-Aided Precoding for Multiantenna Broadcast

Shuiyin Liu; Cong Ling; Xiaofu Wu

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arXiv · 1304.7095

Proximity Factors of Lattice Reduction-Aided Precoding for Multiantenna Broadcast

Shuiyin Liu·Cong Ling·Xiaofu Wu

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Abstract

Lattice precoding is an effective strategy for multiantenna broadcast. In this paper, we show that approximate lattice precoding in multiantenna broadcast is a variant of the closest vector problem (CVP) known as $\eta$-CVP. The proximity factors of lattice reduction-aided precoding are defined, and their bounds are derived, which measure the worst-case loss in power efficiency compared to sphere precoding. Unlike decoding applications, this analysis does not suffer from the boundary effect of a finite constellation, since the underlying lattice in multiantenna broadcast is indeed infinite.

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Shuiyin Liu, Cong Ling, Xiaofu Wu. 2013-04-26. Proximity Factors of Lattice Reduction-Aided Precoding for Multiantenna Broadcast. https://arxiv.org/abs/1304.7095

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