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arXiv · 2506.20050

Near-Field SWIPT Using XL-MIMO: Power Allocation and Subarray Activation

Muhammad Zeeshan Mumtaz·Mohammadali Mohammadi·Hien Quoc Ngo·Michail Matthaiou
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Abstract

This paper investigates the simultaneous wireless information and power transfer (SWIPT) capability of a modular extremely large multiple-input multiple-output (XL-MIMO) system, in the context of power consumption (PC) efficiency. The network users are divided into two functional categories: information decoding (ID) users and energy harvesting (EH) users. Non-stationary near-field channels are considered whilst the users are located in spatially distinct visibility regions (VRs). We formulate a two-tier joint optimization problem to minimize the PC, taking into account the power allocation (PA) for ID and EH users, along with the activation of constituent XL-MIMO subarrays. This complicated mixed-integer problem is transformed into more tractable formulations and efficient algorithms are proposed for solving them. The numerical results demonstrate that the overall PC of the XL-MIMO system for the proposed method is reduced by more than 60% in comparison to the benchmark scheme of equal PA with full subarray activation (SA) and 30% against the case of optimized PA with full SA, while satisfying the quality-of-service (QoS) constraints on both the downlink rate of the ID users and harvested energy at the EH users.

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Muhammad Zeeshan Mumtaz, Mohammadali Mohammadi, Hien Quoc Ngo, Michail Matthaiou. 2025-06-24. Near-Field SWIPT Using XL-MIMO: Power Allocation and Subarray Activation. https://arxiv.org/abs/2506.20050

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