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arXiv · 1705.00122

Branch-and-Bound Precoding for Multiuser MIMO Systems with 1-Bit Quantization

Lukas T. N. Landau·Rodrigo C. de Lamare
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Abstract

Multiple-antenna systems is a key technique to serve multiple users in future wireless systems. For low energy consumption and hardware complexity we first consider transmit symbols with constant magnitude and then 1-bit digital-to-analog converters. We propose precoding designs which maximize the minimum distance to the decision threshold at the receiver. The precoding design with 1-bit DAC corresponds to a discrete optimization problem, which we solve exactly with a branch-and-bound strategy. We alternatively present an approximation based on relaxation. Our results show that the proposed branch-and-bound approach has polynomial complexity. The proposed methods outperform existing precoding methods with 1-bit DAC in terms of uncoded bit error rate and sum-rate. The performance loss in comparison to infinite DAC resolution is small.

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Lukas T. N. Landau, Rodrigo C. de Lamare. 2017-11-10. Branch-and-Bound Precoding for Multiuser MIMO Systems with 1-Bit Quantization. https://doi.org/10.1109/lwc.2017.2740386

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