This article introduces a new small‐sized antenna designed and produced for application in wireless binaural hearing aids. Taking into consideration the antenna position and design of binaural hearing aids, we suggest two different types of small antennas. To reduce the size of both antennas, we used a slot structure and a high‐dielectric constant material. The side that contacts the human skin was coated with a polydimethylsiloxane material that does not cause irritation even with long periods of usage. The proposed antennas were designed to be very small: the human‐body‐contact antenna is 4 × 3.2 × 0.201 mm, and the human‐body‐noncontact antenna is 4 × 4.5 × 0.735 mm. The two antennas operate at the center frequency of 8 GHz, and have an impedance bandwidth greater than 1 GHz. The characteristics of the return loss and radiation pattern were verified for these two antennas by performing the simulation using a three‐dimension phantom, which applied the human electrical properties and practical tests, and the communication performance were verified through the S21 experiment. In addition, by performing the location‐specific S21 experiment and comparing, the location with the best communication performance was determined. Experimental and simulation results in the Case 1 position showed excellent characteristics: the body‐contact antenna exhibited −55.8 dB, and the nonbody‐contact antenna exhibited −55.1 dB. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1883–1889, 2015

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In this article, we propose a monostatic radiometry system for measuring the internal temperature of human tissue, while simultaneously performing radio frequency (RF) hyperthermia treatment. To demonstrate the adequacy of the proposed scheme, we present the results of experiments conducted on pork samples, which have a biological structure and electrical characteristics that are quite similar to those of the human body. We propose to use S‐band total power radiometry. The radiometry frequency was set at 3.85 GHz, with an operating bandwidth of 220 MHz, system gain of 66.95 dB, total system noise figure of 1.75 dB, and a sensitivity of 0.27 K. In order to prevent damage to the radiometry system, an RF switch and a low‐pass filter were added at the front‐end of the monostatic radiometry system to obtain sufficient isolation from the heating system. Using the skin, fat, and muscle tissue models, we performed both experiments and numerical simulations for a biological tissue model using a single dual‐band rectangular waveguide antenna operated at 5.725 GHz for microwave heating. In addition, we tested the proposed monostatic radiometry system in real‐time using pork samples, with an experimental setup capable of simultaneous microwave heating and radiometric temperature measurement. The system performance was verified by comparing the experimental radiometric results with the actual measured temperatures and simulation results.