Optimal SWIPT Receiver Architecture and Achievable Rate–Energy Region

Determine whether a practical simultaneous wireless information and power transfer (SWIPT) receiver architecture exists that achieves a rate–energy region strictly between that of the ideal receiver and those of the time-switching, power-splitting, integrated, and antenna-switching receivers, and, if such an architecture exists, characterize and construct the optimal energy-harvesting and information-decoding receiver together with its achievable rate–energy tradeoff.

Background

The paper analyzes SWIPT receiver designs and their inherent rate–energy tradeoffs. It introduces four practical receiver structures—time switching (TS), power splitting (PS), integrated receiver (IntRx), and antenna switching (AS)—and compares their achievable rate–energy regions against that of an idealized receiver that can simultaneously decode information and harvest energy without tradeoff.

After presenting these regions and noting that PS strictly outperforms TS while IntRx has distinct advantages at high energy demands, the authors explicitly state that the optimal EH–ID receiver is unknown and that it is unclear whether a non-trivial rate–energy region between the ideal and the currently introduced practical receivers is achievable. This frames a concrete open problem on both existence and characterization of an optimal practical SWIPT receiver.