A Miniature Wearable Antenna with Finite-Size High Impedance Surfaces for Smart-Watch Applications
| Name | Year |
| Ting-Yu Ku | 2015 |
| Keywords | |
| directive antennas, high impedance surfaces, mobile antennas, optimization methods |
This paper proposes a novel antenna structure on a miniaturized high impedance surface (HIS) for smart-watch applications. Conventionally, HISs are periodic configurations with large sizes. The performance of HISs must be characterized by unit-cell simulations, which emulate the reflection phase of an infinite-size HIS and observe the frequency with zero reflection phase. However, as the entire design space of HISs becomes electrically small, such as 0.3 λ × 0.3 λ, this method becomes improper because the HIS structure is no longer an infinite and periodic configuration. Thus, it raises the design difficulty for the wearable antenna on a finite-size HIS. This paper uses a new method to characterize the performance of finite-size HISs; accordingly, the total dimension of the proposed antenna is only 38 × 38 × 3 mm3 (at 2.4 GHz), yet the antenna performances are impressing. The directivity of the antenna is increased by 4.09 dB as compared to a conventional printed-circuit-board (PCB) antenna; in addition, the front-to-back ratio is increased from 0.5 dB to 15 dB, the specified absorption rate (SAR) is reduced by 90%, and the frequency detuning effects due to the presence of body tissues are minimized. Simulated and measured results are presented to demonstrate the validity of the proposed antenna.
Publications
- Y.-S. Chen and T.-Y. Ku, “A low-profile wearable antenna using a miniature high impedance surface for smartwatch applications,” IEEE Antennas Wireless Propag. Lett., vol. 15, pp. 1144–1147, 2016.
- Y.-S. Chen and T.-Y. Ku, “Development of a compact LTE dual-band antenna using fractional factorial design,” IEEE Antennas Wireless Propag. Lett., vol. 14, pp. 1097–1100, 2015.
- Y.-S. Chen and T.-Y. Ku, “Efficiency improvements of antenna optimization using orthogonal fractional experiments,” Int. J. Antennas Propag., vol. 2015, pp. 1–12, Oct. 2015.
- T.-Y. Ku and Y.-S. Chen, “Wearable antenna design on finite-Size high impedance surfaces for smart-watch applications,” IEEE AP-S International Symposium and URSI Radio Science Meeting, Vancouver, Canada, July 2015, pp. 938‒939.
- Y.-S. Chen and T.-Y. Ku, “Pixelated design of multiple antennas for MIMO handset applications,” in Asia-Pacific Symp. Electromagn. Compat. (APEMC), Taipei, Taiwan, May 2015, pp. 192–195.
