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arXiv · 2403.09958

Decentralizing Coherent Joint Transmission Precoding via Deterministic Equivalents

Yuhao Liu·Xinyu Bian·Yizhou Xu·Tianqi Hou·Wenjie Wang·Yuyi Mao·Jun Zhang
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Abstract

In order to control the inter-cell interference for a multi-cell multi-user multiple-input multiple-output network, we consider the precoder design for coordinated multi-point with downlink coherent joint transmission. To avoid costly information exchange among the cooperating base stations in a centralized precoding scheme, we propose a decentralized one by considering the power minimization problem. By approximating the inter-cell interference using the deterministic equivalents, this problem is decoupled to sub-problems which are solved in a decentralized manner at different base stations. Simulation results demonstrate the effectiveness of our proposed decentralized precoding scheme, where only 2 ~ 7% more transmit power is needed compared with the optimal centralized precoder.

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Yuhao Liu, Xinyu Bian, Yizhou Xu, Tianqi Hou, Wenjie Wang, Yuyi Mao, Jun Zhang. 2024-03-15. Decentralizing Coherent Joint Transmission Precoding via Deterministic Equivalents. https://arxiv.org/abs/2403.09958

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