volume | PIER Journals

Abstract

The integration of a loop antenna into the top metal frame of a smartwatch wearable device is introduced. The loop antenna was made of a 1-mm thick, rectangular metal frame, which was stacked 1.5 mm above the lower metal frame of the watch having a size of 7 mm × 35 mm × 40 mm. The system circuit board was encircled by the lower, rectangular metal frame with a 1 mm gap between the perimeter of the ground plane and the metal frame. The top metal frame was fed in a corner on the frame's longer edge with two shorting portions short-circuited to the system ground. By carefully positioning the two shorting for the top metal frame, the proposed loop antenna can provide the global positioning system (GPS) operation at 1575 MHz for smartwatch applications.

1. Chen, Y. S. and T. Y. Ku, "A low-profile wearable antenna using a miniature high impedance surface for smartwatch applications," IEEE Wireless Antennas Propagat. Lett., Vol. 15, 1144-1147, 2016.
doi:10.1109/LAWP.2015.2496366

2. Su, S. W. and Y. T. Hsieh, "Integrated metal-frame antenna for smartwatch wearable device," IEEE Trans. Antennas Propagat., Vol. 63, 3301-3305, 2015.
doi:10.1109/TAP.2015.2428736

3. Wu, D., S. W. Cheung, Q. L. Li, and T. I. Yuk, "Slot antenna for all-metal smartwatch applications," European Conf. Antennas Propagat., 1144-1147, Davos, Switzerland, 2016.

4. Ahn, J., S. Kim, M. J. Lee, A. S. Kim, and Y. Kim, "Small global positioning system antennas on a printed circuit board for mobile handsets loaded with lumped elements," Microwave Opt. Technol. Lett., Vol. 55, 576-580, 2013.
doi:10.1002/mop.27350

5. Su, S. W., "Linearly-polarized patch PIFA for GPS/GLONASS operation for tablet-computer applications," Microwave Opt. Technol. Lett., Vol. 57, 149-153, 2015.
doi:10.1002/mop.28800

6. Wong, K. L., Z. G. Liao, and W. Y. Li, "Hybrid loop/monopole antenna with a passive bandstop circuit for the LTE/GPS operation in the tablet computer," Microwave Opt. Technol. Lett., Vol. 58, 630-635, 2016.
doi:10.1002/mop.29635

7. Su, S. W., "Concurrent dual-band six-loop-antenna system with wide 3-dB beamwidth radiation for MIMO access points," Microwave Opt. Technol. Lett., Vol. 52, 1253-1258, 2010.
doi:10.1002/mop.25208

8. Su, S. W., "High-gain dual-loop antennas for MIMO access points in the 2.4/5.2/5.8 GHz bands," IEEE Trans. Antennas Propagat., Vol. 58, 2412-2419, 2010.
doi:10.1109/TAP.2010.2048871

9. Su, S. W., "Integration of loop and slot antennas into one-piece metal plate for concurrent 2.4- and 5-GHz wireless local area network operation," Microwave Opt. Technol. Lett., Vol. 54, 815-820, 2012.
doi:10.1002/mop.26624

10. Su, S. W., "Compact four-loop-antenna system for concurrent, 2.4- and 5-GHz WLAN operation," Microwave Opt. Technol. Lett., Vol. 56, 208-215, 2014.
doi:10.1002/mop.28020

11. ANSYS HFSS, ANSYS Inc., http://www.ansys.com/Products/Electronics/ANSYS-HFSS.

12. SG 64, SATIMO, , http://www.satimo.com/content/products/sg-64.

13. Wang, J. H., "Antennas for global navigation satellite system (GNSS)," Proc. IEEE, Vol. 100, 2349-2355, 2012.
doi:10.1109/JPROC.2011.2179630

14. Volakis, J. L., Antenna Engineering Handbook, 4th Ed., Chapter 6, 16-19, McGraw-Hill, New York, 2007.

15. Balanis, C. A., Antenna Theory: Analysis and Design, 3rd Ed., Chapter 2, Wiley, New York, 2012.

16. CTIA, The Wireless Association, , http://www.ctia.org/.

17. Forearm phantom with hand, SPEAG, , Schmid & Partner Engineering AG, http://www.speag.com/products/em-phantom/hands/forearm-2/.

18. Sojuyigbe, S. and K. Daniel, "Wearables/IOT devices challenges and solutions to integration of miniature antennas in close proximity to the human body," IEEE Symposium on Electromagnetic Compatibility and Signal Integrity, 75-78, Santa Clara, CA, 2015.

Dr. Saou-Wen Su

Dr. Cheng-Tse Lee