February 2007 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [PHY considerations for low power body area networks (BAN)] Date Submitted: [March 17, 2008] Source: [Zhanfeng Jia, Jason Ellis and Amal Ekbal] Company [Qualcomm, Inc.] Address [5775 Morehouse Drive, San Diego, CA 92121] Voice:[+1-858-845-6353], E-Mail:[jason.ellis@qualcomm.com] Abstract: [This document presents an option for 802.15.6 PHY frequency band] Purpose: [To promote a discussion of PHY frequency band options available for 802.15.6] 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.

PHY Considerations for Low Power Body Area Networks (BANs) February 2007 PHY Considerations for Low Power Body Area Networks (BANs) Draft Contribution for March 2008 IEEE 802.15.6 Meeting Jason Ellis Amal Ekbal Zhanfeng Jia

Key Points Unlicensed Spectrum Technology Benefits February 2007 Key Points Unlicensed Spectrum Technology Benefits Initial Propagation Results Low Cost Antenna Solutions

Available Unlicensed Spectrum February 2007 Available Unlicensed Spectrum ISM: 900MHz and 2.4GHz Very congested WiFi Bluetooth Zigbee Cordless Phones Microwave Overs Misc UNII: 5GHz – less congested Some WiFI (802.11a, possible small amount of 11g) UWB: 3.1-10.6GHz Newly unlicensed globally, WiMedia (Wireless USB and Bluetooth 3.0) Unique properties for communication 60GHz Globally unlicensed spectrum Basis for new very high speed and wireless video standards

The global unlicensed spectrum “window” February 2007 Regulatory Status US UWB legal 3.1-10.6 GHz EU has legalized 6-8.5GHz Japan has legalized 7.25-10.25GHz for high data rate (>50Mbps) Regulators still working on lower data rate 7.25-8.50 GHz is a globally available “window” of spectrum

A closer look at 7.25-8.5 GHz Benefits February 2007 A closer look at 7.25-8.5 GHz Benefits Worldwide unlicensed spectrum Low in-band interference compared with ISM and UNII Small antenna sizes lead to small form factors Doubling frequency halves the antenna in each dimension Good spatial reuse for dense deployments (e.g. hospitals, cars, buses,) Multipath capture – good for use in hospital, ship, container environments Body area propagation is acceptable No DAA requirements (detecting victim receivers) on low power BAN technologies Low complexity, implementable in standard CMOS processes

High Frequency Antennas can be Low Cost February 2007 High Frequency Antennas can be Low Cost $0.02 Antennas (inexpensive) Very small Omni directional antenna Perform well in 7.25-8.5GHz Source: Antenna picture and gain plots from PUBs, http://timederivative.com/pubs.html

Initial Path Loss Measurements February 2007 Initial Path Loss Measurements Measurements with off-the-shelf test-equipment to send and receive impulse waveforms at 7.25 to 9 GHz Digital Storage Oscilliscope (DSO) captures Tx and Rx waveforms Signals demodulated in Matlab Preliminary measurements for (see following slides) line-of-sight, 2’ pocket-to-ear Thru-wall and thru-door

Typical Channel Measurements -1 February 2007 Typical Channel Measurements -1 Line-of-Sight, 2 feet Ear to Opposite Pants pocket 2.5ns 5ns Ep/N0 = 34dB Ep/N0 = 28dB

Typical Channel Measurements -2 February 2007 Typical Channel Measurements -2 Thru-Wall, 4.5’ 5ns Thru-door, 4.2’ 5ns Ep/N0 = 27dB Ep/N0 = 27dB Through interior office wall Through interior office door

Typical Channel Measurements: Pocket to Ear February 2007 Typical Channel Measurements: Pocket to Ear Using a Software Radio test setup we measured the path loss for various pocket-to-ear scenarios and for different environments 2 different cases considered: Pant’s pocket to ear on same and opposite sides Path Loss computed as: Includes antenna losses (Note: average gain is -2dB at either end) Location Pant’s Pocket to Same-Side Ear Path Loss [dB] Pant’s Pocket to Opposite Ear Path Loss [dB] Antenna Range (Free Space) 66.33 76.69 Lab Environment – Person 1 59.58 67.71 Lab Environment – Person 2 68.43 65.91 Outside, on parking structure 72.67 65.62 Large Hall 59.67 54.25 Lunchroom, sitting 70.58 76.3 Lunchroom, standing 64.55 66.57 Office, sitting 66.06 67.76 Office, standing 57.8 67.42 Small Hall 60.33 65.87 “Pants” pocket to opposite ear

February 2007 Conclusions Newly unlicensed spectrum presents an opportunity for global BAN apps Global “window” presently limited to 7.25GHz – 8.5GHz operation High frequencies enable high density and high reuse applications Inexpensive options exist for omni-directional antennas in 7.25-8.5GHz Initial tests suggest path loss performance is quite reasonable, even at higher frequencies Suggest 802.15.6 standards committee not preclude consideration of appropriate technology proposals for this band