• Title/Summary/Keyword: multiuser multiple-input single-output (MISO) broadcasting

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Robust Transceiver Designs in Multiuser MISO Broadcasting with Simultaneous Wireless Information and Power Transmission

  • Zhu, Zhengyu;Wang, Zhongyong;Lee, Kyoung-Jae;Chu, Zheng;Lee, Inkyu
    • Journal of Communications and Networks
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    • v.18 no.2
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    • pp.173-181
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    • 2016
  • In this paper, we address a new robust optimization problem in a multiuser multiple-input single-output broadcasting system with simultaneous wireless information and power transmission, where a multi-antenna base station (BS) sends energy and information simultaneously to multiple users equipped with a single antenna. Assuming that perfect channel-state information (CSI) for all channels is not available at the BS, the uncertainty of the CSI is modeled by an Euclidean ball-shaped uncertainty set. To optimally design transmit beamforming weights and receive power splitting, an average total transmit power minimization problem is investigated subject to the individual harvested power constraint and the received signal-to-interference-plus-noise ratio constraint at each user. Due to the channel uncertainty, the original problem becomes a homogeneous quadratically constrained quadratic problem, which is NP-hard. The original design problem is reformulated to a relaxed semidefinite program, and then two different approaches based on convex programming are proposed, which can be solved efficiently by the interior point algorithm. Numerical results are provided to validate the robustness of the proposed algorithms.

MMSE Transmit Optimization for Multiuser Multiple-Input Single-Output Broadcasting Channels in Cognitive Radio Networks

  • Cao, Huijin;Lu, Yanhui;Cai, Jun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.9
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    • pp.2120-2133
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    • 2013
  • In this paper, we address the problem of linear minimum mean-squared error (MMSE) transmitter design for the cognitive radio (CR) multi-user multiple-input single-output (MU-MISO) broadcasting channel (BC), where the cognitive users are subject to not only a sum power constraint, but also a interference power constraint. Evidently, this multi-constraint problem renders it difficult to solve. To overcome this difficulty, we firstly transform it into its equivalent formulation with a single constraint. Then by utilizing BC-MAC duality, the problem of BC transmitter design can be solved by focusing on a dual MAC problem, which is easier to deal with due to its convexity property. Finally we propose an efficient two-level iterative algorithm to search the optimal solution. Our simulation results are provided to corroborate the effectiveness of the proposed algorithm and show that this proposed CR MMSE-based scheme achieves a suboptimal sum-rate performance compared to the optimal DPC-based algorithm with less computational complexity.