March 2008
Slide 1
doc.: IEEE 802.15-<160r1>
Submission
Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)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:[[email protected]]
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.
March 2008
Slide 2
doc.: IEEE 802.15-<160r1>
Submission
PHY Considerations for Low Power Body Area Networks (BANs)
Draft Contribution for March 2008 IEEE 802.15.6 Meeting
Jason EllisAmal Ekbal
Zhanfeng Jia
March 2008
Slide 3
doc.: IEEE 802.15-<160r1>
Submission
Key Points
• Unlicensed Spectrum
• Technology Benefits
• Initial Propagation Results
• Low Cost Antenna Solutions
March 2008
Slide 4
doc.: IEEE 802.15-<160r1>
Submission
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)• Cordless Phones• Misc
• 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
March 2008
Slide 5
doc.: IEEE 802.15-<160r1>
Submission
The global unlicensed spectrum “window”
• 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
March 2008
Slide 6
doc.: IEEE 802.15-<160r1>
Submission
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
March 2008
Slide 7
doc.: IEEE 802.15-<160r1>
Submission
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
March 2008
Slide 8
doc.: IEEE 802.15-<160r1>
Submission
Initial Path Loss Measurements
Pulse Generator
Pulse Shaper
BPF PA
RF Coupler
RF Coupler
BPFLNA
DSO
Post
Processing
-10 dB
Signal Generator
for Blockers / Jammers
-10 dB
Channel
Transmit Chain
Receive Chain
Capture T
rigger
Picosecond 4015DPicosecond 4015D-
RPH Narda 4226-10
Ciao WirelessCA611-441
Narda 4226-10
Ciao WirelessCA611-441
Tektronix TDS6124C
• 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
March 2008
Slide 9
doc.: IEEE 802.15-<160r1>
Submission
Typical Channel Measurements -1Line-of-Sight, 2 feet
Ear to Opposite Pants pocket
2.5ns 5ns
Ep/N0 = 34dBEp/N0 = 28dB
Path loss = 49dBPath loss = 55dB
March 2008
Slide 10
doc.: IEEE 802.15-<160r1>
Submission
Typical Channel Measurements -2Thru-Wall, 4.5’
Thru-door, 4.2’
5ns
5ns
Through interior office wallPath loss = 56dB
Through interior office doorPath loss = 56dB
Ep/N0 = 27dB
Ep/N0 = 27dB
March 2008
Slide 11
doc.: IEEE 802.15-<160r1>
Submission
Typical Channel Measurements: Pocket to Ear
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
• 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)
“Pants” pocket to opposite ear
oAntennaTxPowerInt
ofAntennaRxPowerOutPathLoss 10log10
March 2008
Slide 12
doc.: IEEE 802.15-<160r1>
Submission
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