Transmitter and Precoding Order Optimization for Nonlinear Downlink Beamforming

Thomas Michel; Gerhard Wunder

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arXiv · cs/0702122

Transmitter and Precoding Order Optimization for Nonlinear Downlink Beamforming

Thomas Michel·Gerhard Wunder

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Abstract

The downlink of a multiple-input multiple output (MIMO) broadcast channel (BC) is considered, where each receiver is equipped with a single antenna and the transmitter performs nonlinear Dirty-Paper Coding (DPC). We present an efficient algorithm that finds the optimum transmit filters and power allocation as well as the optimum precoding order(s) possibly affording time-sharing between individual DPC orders. Subsequently necessary and sufficient conditions for the optimality of an arbitrary precoding order are derived. Based on these we propose a suboptimal algorithm showing excellent performance and having low complexity.

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Thomas Michel, Gerhard Wunder. 2007-02-22. Transmitter and Precoding Order Optimization for Nonlinear Downlink Beamforming. https://arxiv.org/abs/cs/0702122

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