1. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 1 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title:[Path-Loss Exponents of Ultra Wideband Signals in Line-of-Sight Environments] Date Submitted:[14 March, 2004] Source: [Shunsuke Sato and Takehiko Kobayashi] Company [UWB Technology Institute, Communications Research Laboratory / Tokyo Denki University] Address [Tokyo Denki University, 2-2 Kanda-nishiki-cho, Chiyoda-ku, Tokyo 101-8457, Japan] Voice [+81 3 5280 3839] E-Mail: [shunsuke@grace.c.dendai.ac.jp, koba@c.dendai.ac.jp] Re: [Status report of the 802.15.4a channel modeling subgroup] Abstract:[This contribution describes a new line-of-sight path loss formula for ultra wideband signals in the presence of the ground plane reflection.] Purpose:[Reports on a UWB pass loss formula for IEEE802.15TG4a] Notice:This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release:The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.

2. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 2 Path-Loss Exponents of Ultra Wideband Signals in Line-of-Sight Environments Shunsuke Sato and Takehiko Kobayashi Communications Research Laboratory Tokyo Denki University Presented by Honggang Zhang, Yuko Rikuta Communications Research Laboratory

3. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 3 Table of contents Background Narrowband two-path model Conventional UWB two-path model Proposal of a new UWB two-path model formula Experimental verification Conclusion

4. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 4 Background Conventional UWB path-loss models Free Space : path loss exponent = 2 UWB Two path model [1] : –Direct wave plus reflected wave from the ground plane –Path loss exponent  changes from 2 to  at a breakpoint –Breakpoint distance = 2 m (no reason given) –Applicable to the order of meters (?) Another UWB two path model [2] –Breakpoint distance is not given Proposal for a new line-of-sight path loss formula of UWB signals in the presence of the ground plane reflection.

5. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 5 Narrowband two-path model [3]

6. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 6 Path-loss based on the narrowband two-path model h T = h R = 1 m ，  = 1,  =  Path loss exponent changes 2 to 4 at the breakpoint Breakpoint

7. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 7 The narrowband two-path model formula Distance between the transmitting and receiving antennas x, transmitting antenna height h T, receiving antenna height h R, frequency f ， velocity of the light c, and ground reflection coefficient  exp ( j  )

8. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 8 Breakpoint distance The Freznel zone distance [3]: The linear envelope with a slope of x 2 intersects the line of approximation with a slope of x 4 : h T = h R = 1 m

9. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 9 The proposed UWB two-path model formula [4] The path loss of a UWB the integral of the CW. Distance between the transmitting and receiving antennas x, transmitting antenna height h T, receiving antenna height h R, lowest frequency f L ， highest frequency f H ， velocity of the light c, and ground reflection coefficient  exp ( j  ).

10. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 10 Predicted UWB path-loss characteristics h T = h R = 1 m,  = 1,  = , frequency=3.1-10.6 GHz ．

11. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 11 Dependence of f L and bandwidth f L = 3.1 GHz f L = 6.0 GHz h T =h R =1 m

12. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 12 Breakpoint distances and path-loss exponents calculated by the proposed formula f L = 3.1 GHz, h T = h R = 1 m

13. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 13 Breakpoint distance f L =3.1 GHz is the most appropriate:

14. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 14 Experimental setup Bandwidth ： 3.1-10.6 GHz, Polarization ： Vertical x

15. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 15 Experimental verification

16. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 16 Conclusion Derived a new UWB two-path model formula –The path-loss exponent of UWB signals changes from approximately 2 to 4 at the breakpoint. –Breakpoint distance =, Confirmed by an indoor experiment

17. doc.: IEEE802.15-04-0111-00-004a Submission March 2004 Communications Research Laboratory Slide 17 References [1] ITU-R Doc. 1-8/047-E, March 28, 2003. [2] ITU-R Doc, 1-8/32-E, Jan 16, 2003. [3] W. C. Y. Lee, Mobile Communications Engineering, 2nd ed., pp. 116-120, McGraw-Hill, New York, 1982. [4]S. Sato and T. Kobayashi, “Path-loss exponents of ultra wideband signals in line-of-sight environments,” 2004 IEEE International Symposium on Spread Spectrum Techniques and Applications, Sydney, Australia, Aug. 30- Sept. 2, 2004, submitted.