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Clinical effectiveness of hyperthermia treatments, in which tumor tissue is artificially heated to 40–44 °C for 60–90 min, can be hampered by a lack of accurate temperature monitoring. The need for noninvasive temperature monitoring in the head and neck region (H&amp, N) and the potential of MR thermometry prompt us to design an MR compatible hyperthermia applicator: the MRcollar. In this work, we validate the design, numerical model, and MR performance of the MRcollar. The MRcollar antennas have low reflection coefficients (&lt, −15 dB) and the intended low interaction between the individual antenna modules (&lt, −32 dB). A 10 °C increase in 3 min was reached in a muscle-equivalent phantom, such that the specifications from the European Society for Hyperthermic Oncology were easily reached. The MRcollar had a minimal effect on MR image quality and a five-fold improvement in SNR was achieved using the integrated coils of the MRcollar, compared to the body coil. The feasibility of using the MRcollar in an MR environment was shown by a synchronous heating experiment. The match between the predicted SAR and measured SAR using MR thermometry satisfied the gamma criteria [distance-to-agreement = 5 mm, dose-difference = 7%]. All experiments combined show that the MRcollar delivers on the needs for MR—hyperthermia in the H&amp, N and is ready for in vivo investigation.

Radiative (or far-field) energy replenishment for devices such as smartphones, laptops, robots, and small electric appliances paves the way to autonomous and continuous devices functioning, thus bypassing the need of operation interruptions, human maintenance activities, and replenishment by wired transformers. In this work, we investigate the feasibility of using a properly engineered antenna array able to deliver radiative power to devices in need of energy replenishment during their normal and unsupervised activity, whose locations are unknown. Both the case of single and multiple devices needing energy replenishment are addressed. A quantitative proof-of-concept study is carried out to validate the proposed approach. A 3D scenario is simulated to study the case of devices in need of energy replenishment within a standard office environment. Different antenna array configurations are investigated and the corresponding performances benchmarked against a standard installation of recharging antennas. Results confirm the outstanding capability of the proposed approach in terms of confinement and maximization of power transfer. Finally, in this framework, we also propose an efficient communication protocol that is able to manage multiple recharge demand given different operational rules.