Recent advances on wireless energy transfer led to a promising solution for powering future Internet of Things (IoT) devices enabled by the upcoming sixth generation (6G) era. In this paper, we overview the main architectures, challenges and techniques for efficient wireless powering. We emphasize on the suitability of Channel State Information (CSI) -free strategies when powering simultaneously a massive number of devices. We show that even without considering the energy resources required for CSI acquisition, the gains from operating with CSI decrease quickly as the number of powered devices increases, while distributed CSI-free strategies become even more advantageous by widening the energy coverage region with high reliability. Overall, advances in the system design and in resource allocation strategies are required for optimizing the energy supplying process, specially under the challenges imposed by future networks .
Recent advances on wireless energy transfer (WET) make it a promising solution for powering future Internet of Things (IoT) devices enabled by the upcoming sixth generation (6G) era. The main architectures, challenges and techniques for efficient and scalable wireless powering are overviewed in this paper. Candidates enablers such as energy beamforming (EB), distributed antenna systems (DAS), advances on devices' hardware and programmable medium, new spectrum opportunities, resource scheduling and distributed ledger technology are outlined. Special emphasis is placed on discussing the suitability of channel state information (CSI) -limited/free strategies when powering simultaneously a massive number of devices. The benefits from combining DAS and EB, and from using average CSI whenever available, are numerically illustrated. The pros and cons of the state-of-the-art CSI-free WET techniques in ultra-low power setups are thoroughly revised, and some possible future enhancements are outlined. Finally, key research directions towards realizing WET-enabled massive IoT networks in the 6G era are identified and discussed in detail .
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In this paper, we overview the
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and scalable wireless powering are overviewed in this paper. Candidates enablers such as energy beamforming (EB), distributed antenna systems (DAS), advances on devices' hardware and programmable medium, new spectrum opportunities, resource scheduling and distributed ledger technology are outlined. Special emphasis is placed on discussing
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Channel State Information
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We show that even without considering the energy resources required for CSI acquisition, the gains from operating with CSI decrease quickly as the number of powered devices increases, while distributed
The benefits from combining DAS and EB, and from using average CSI whenever available, are numerically illustrated. The pros and cons of the state-of-the-art
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strategies become even more advantageous by widening the energy coverage region with high reliability. Overall, advances in the system design and in resource allocation strategies are required for optimizing the energy supplying process, specially under the challenges imposed by future networks
WET techniques in ultra-low power setups are thoroughly revised, and some possible future enhancements are outlined. Finally, key research directions towards realizing WET-enabled massive IoT networks in the 6G era are identified and discussed in detail