Ho-Yu Lin

Performance of Implantable Folded Dipole Antenna for In-Body Wireless Communication

Implantable devices have been continually anticipated as a future tool for in-body wireless communication because of their potential to replace cable connectivity with biological telemetry monitoring. This paper presents an implanted compact folded antenna of 20.3 mm × 0.8 mm × 0.8 mm that is designed to operate at one of the UHF bands (0.951-0.956 GHz). The measurement is implemented with an equivalent human phantom such as layered phantom representing the human arm. When the proposed antenna is implanted into a human arm, it has a maximum antenna gain of -23.5 dBi and wireless communication is viable because the margin exceeds 20 dB, according to link budget calculations.

Characteristics of Electric Field and Radiation Pattern on Different Locations of the Human Body for In-Body Wireless Communication

An in-body wireless communication system has attracted increasing attention because it can replace the connectivity of biological telemetry monitoring. However, the human body is a very complex environment (lossy, dispersive, and inhomogeneous) and affects the electromagnetic (EM) wave in the near field. Moreover, the entire human geometry affects the radiation pattern in the far field. This communication presents the behavior of the EM wave in the near and far fields at 2.45 GHz when a dipole antenna (used as an implantable antenna) is embedded in the vicinity of the clavicle, upper arm, lower arm, and hand of a human body. The effect on the electric field and radiation performance is simulated by the finite-difference time-domain method. By introducing a three-layered phantom, the antenna performance is confirmed. Moreover, the measured and simulated results are in good agreement with each other. The information derived from this study can be used in the evaluation of the link budget of in-body wireless communication.

Novel small antennas for body-centric wireless communications

Body-centric wireless communications (BCWCs) using wearable or implantable wireless devices are received an increasing amount of attention due to many applications such as medical care system, identification system, smart home and personal entertainment. In this paper, we will introduce an UHF band (0.95 GHz) implantable antenna and a novel dual-mode small antenna for on-body (10 MHz) and off-body (2.45 GHz) communications for BCWCs.

Corrections to “Performance of Implantable Folded Dipole Antenna for In-Body Wireless Communication” [Mar 13 1363-1370]

In the above paper (ibid., vol. 61, no. 3, pp. 1363-1370, Mar. 2013), the units of the required RX power RP and available RX power AP erroneously appeared as [dB], whereas they should have appeared as [dB/Hz].

Physical human phantoms for evaluation of implantable antennas

In recent years, body-centric wireless communications (BCWCs) are paid attention a lot in medical applications, because it has the ability to reduce malpractice and to ameliorate the quality of life of the patients. Interactions between the human body and electromagnetic (EM) waves radiated from an antenna are generally estimated by numerical calculation and experiments. In here, interactions mean the influence of the human body on the antenna performance and an influence of EM waves on the human body. Moreover, a realistic human body is represented by numerical or tissue-equivalent human phantom. In this paper, we talk about what role would tissue-equivalent phantom play in evaluation of implantable antennas by embedding a dipole antenna (0.953 GHz) into whole-body voxel human models and three simple phantoms (layered, rectangular and cylindrical structures). Calculation is completed by the finite-different time domain (FDTD) method.