1. February 2007
Project: IEEE P 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:[ ],
Abstract: [This document presents an option for PHY frequency band]
Purpose: [To promote a discussion of PHY frequency band options available for ]
Notice: This document has been prepared to assist the IEEE P 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 P

2. 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 Meeting
Jason Ellis
Amal Ekbal
Zhanfeng Jia

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

4. 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: GHz
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

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

6. A closer look at 7.25-8.5 GHz Benefits
February 2007
A closer look at 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

7. 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 GHz
Source: Antenna picture and gain plots from PUBs,

8. Initial Path Loss Measurements
February 2007
Initial Path Loss Measurements
Measurements with off-the-shelf test-equipment to send and receive impulse waveforms at 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

9. 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

10. 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

11. 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

12. 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 GHz
Initial tests suggest path loss performance is quite reasonable, even at higher frequencies
Suggest standards committee not preclude consideration of appropriate technology proposals for this band