DOI QR코드

DOI QR Code

Measurement and Comparison of Wi-Fi and Super Wi-Fi Indoor Propagation Characteristics in a Multi-Floored Building

  • Hwang, Gyumin (Sysmate, Inc.) ;
  • Shin, Kyubo (School of Electrical and Computer Engineering, Ulsan National Institute of Science and Technology (UNIST)) ;
  • Park, Sanghyeok (School of Electrical and Computer Engineering, Ulsan National Institute of Science and Technology (UNIST)) ;
  • Kim, Hyoil (School of Electrical and Computer Engineering, Ulsan National Institute of Science and Technology (UNIST))
  • Received : 2015.01.12
  • Accepted : 2015.09.07
  • Published : 2016.06.30

Abstract

Super Wi-Fi is a Wi-Fi-like service exploiting TV white space (WS) which is expected to achieve larger coverage than today's Wi-Fi thanks to its superior propagation characteristics. Super Wi-Fi has been materialized as an international standard, IEEE 802.11af, targeting indoor and outdoor applications, and is undergoing worldwide field tests. This paper demonstrates the true potential of indoor Super Wi-Fi, by experimentally comparing the signal propagation characteristics of Super Wi-Fi and Wi-Fi in the same indoor environment. Specifically, we measured the wall and floor attenuation factors and the path-loss distribution at 770MHz, 2.401 GHz, and 5.540 GHz, and predicted the downlink capacity of Wi-Fi and Super Wi-Fi. The experimental results have revealed that TVWS signals can penetrate up to two floors above and below, whereas Wi-Fi signals experience significant path loss even through a single floor. It has been also shown that Super Wi-Fi mitigates shaded regions of Wi-Fi by providing almost-homogeneous data rates within its coverage, performs comparable to Wi-Fi utilizing less bandwidth, and always achieves better spectral efficiency than Wi-Fi. The observed phenomena imply that Super Wi-Fi is suitable for indoor applications and has the potential of extending horizontal and vertical coverage of today's Wi-Fi.

Keywords

Acknowledgement

Grant : Research on Near-Zero Latency Network for 5G Immersive Service

Supported by : National Research Foundation of Korea (NRF), IITP

References

  1. FCC, "Second memorandum opinion and order," ET Docket No. 10-174, Sept. 2010.
  2. Ofcom, "Regulatory requirements for white space devices in the UHF TV band," July 2012.
  3. ETSI, "EN 301 598 white space devices (WSD); wireless access systems operating in the 470 MHz to 790 MHz frequency band," Oct. 2012.
  4. H. Kim, K. Shin, and C. Joo, "Downlink capacity of super Wi-Fi coexisting with conventional Wi-Fi," in Proc. IEEE GLOBECOM, 2013.
  5. IEEE Std 802.11af-2013, "Part 11: Wireless LAN medium access control (MAC) and physical layer (PHY) specifications; amendment 5: TV white spaces operation," Feb. 2014.
  6. S. Seidel and T. Rappaport, "914 MHz path loss prediction models for indoor wireless communications in multifloored buildings," IEEE Trans. Antennas Propag., vol. 40, no. 2, pp. 207-217, 1992. https://doi.org/10.1109/8.127405
  7. J.-F. Lafortune and M. Lecours, "Measurement and modeling of propagation losses in a building at 900 MHz," IEEE Trans. Veh. Technol., vol. 39, no. 2, pp. 101-108, 1990. https://doi.org/10.1109/25.54226
  8. D. Porrat and D. Cox, "UHF propagation in indoor hallways," IEEE Trans. Wireless Commun., vol. 3, no. 4, pp. 1188-1198, 2004. https://doi.org/10.1109/TWC.2004.828023
  9. W. Honcharenko, H. Bertoni, J. Dailing, J. Qian, and H. Yee, "Mechanisms governing UHF propagation on single floors in modern office buildings," IEEE Trans. Veh. Technol., vol. 41, no. 4, pp. 496-504, 1992. https://doi.org/10.1109/25.182602
  10. H. Cao, Z. Zhao, W. Ni, M. El-Hadidy, and T. Kaiser, "Measurement and ray-tracing of wideband indoor channel in UHF TV white space," in Proc. ACM CogART, 2011.
  11. C. Anderson and T. Rappaport, "In-building wideband partition loss measurements at 2.5 and 60 GHz," IEEE Trans. Wireless Commun., vol. 3, no. 3, pp. 922-928, 2004. https://doi.org/10.1109/TWC.2004.826328
  12. M. Lott and I. Forkel, "A multi-wall-and-floor model for indoor radio propagation," in Proc. IEEE VTC-Spring, 2001.
  13. N. Sarkar and K. Sowerby, "Wi-Fi performance measurements in the crowded office environment: A case study," in Proc. ICCT, 2006.
  14. V.-H. Pham and J.-Y. Chouinard, "A Study on the channel and signal cross correlation of UHF DTV channels," in Proc. ISSSE, 2007.
  15. L. Simic, M. Petrova, and P.Mahonen, "Wi-Fi, but not on steroids: Performance analysis of aWi-Fi like network operating in TVWS under realistic conditions," in Proc. IEEE ICC, 2012.
  16. Ettus Research, Universal Software Radio Peripheral. [Online]. Available: http://www.ettus.com
  17. GNU Radio. [Online]. Available: http://www.gnuradio.org/redmine/projects/gnuradio/wiki
  18. RawOFDM. [Online]. Available: http://people.csail.mit.edu/szym/rawofdm/
  19. W. Stutzman and G. Thiele, Antenna Theory and Design. Hoboken, NJ: John Wiley & Sons, Inc., 2013.
  20. W. Malik, B. Allen, and D. Edwards, "Bandwidth-dependent modelling of smallscale fade depth in wireless channels," IET Microw. Antennas Propag., vol. 2, no. 6, pp. 519-528, 2008. https://doi.org/10.1049/iet-map:20080015
  21. T. Rappaport, Wireless communications: Principles and practice. Upper Saddle River, NJ: Prentice Hall, 2002.