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arXiv · 1612.08328

Large-Scale MIMO Secure Transmission with Finite Alphabet Inputs

Abstract

In this paper, we investigate secure transmission over the large-scale multiple-antenna wiretap channel with finite alphabet inputs. First, we show analytically that a generalized singular value decomposition (GSVD) based design, which is optimal for Gaussian inputs, may exhibit a severe performance loss for finite alphabet inputs in the high signal-to-noise ratio (SNR) regime. In light of this, we propose a novel Per-Group-GSVD (PG-GSVD) design which can effectively compensate the performance loss caused by the GSVD design. More importantly, the computational complexity of the PG-GSVD design is by orders of magnitude lower than that of the existing design for finite alphabet inputs in [1] while the resulting performance loss is minimal. Numerical results indicate that the proposed PG-GSVD design can be efficiently implemented in large-scale multiple-antenna systems and achieves significant performance gains compared to the GSVD design.

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BibTeXRIS

Yongpeng Wu, Jun-Bo Wang, Jue Wang, Robert Schober, Chengshan Xiao. 2016-12-26. Large-Scale MIMO Secure Transmission with Finite Alphabet Inputs. https://arxiv.org/abs/1612.08328

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