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doc.: IEEE /0249r0 Submission May 2004 Bart Van Poucke, IMECSlide 3 Body area channel consists of a creeping wave and scattered components. Creeping wave results from waves diffracting around the body This received signal is the creeping wave combined with reflections off of nearby obstacles. Creping wave Component Scattered Components
Citation preview
doc.: IEEE 802.15-04/0249r0
Submission
May 2004
Slide 1 Bart Van Poucke, IMEC
Project: IEEE 802.15 Working Group for Wireless Personal Area Networks (WPANs)Project: IEEE 802.15 Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [Body area channel modeling update ]
Date Submitted: [11May2004]
Source: [Bart Van Poucke] Company [IMEC]Address [Kapeldreef 75, Leuven, Belgium 3001]Voice:[+32(0)16 28 12 11], FAX: [+32(0)16 22 94 00], E-Mail:[[email protected]]Re: [Channel model proposal]
Abstract: [Update on channel model for communication around the body]
Purpose: [Contribute to low power air-interface definition for body area applications]Notice: This document has been prepared to assist the IEEE 802.15. 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 802.15.
Bart Van Poucke, IMECSlide 2
doc.: IEEE 802.15-04/0249r0
Submission
May 2004
Outline
• Body area UWB channel modeling strategy
• Simulation results so far
• Conclusion and Future work
Bart Van Poucke, IMECSlide 3
doc.: IEEE 802.15-04/0249r0
Submission
May 2004
Body area channel consists of a creeping wave and scattered components.
• Creeping wave results from waves diffracting around the body
• This received signal is the creeping wave combined with reflections off of nearby obstacles.
Creping waveComponent
ScatteredComponents
Bart Van Poucke, IMECSlide 4
doc.: IEEE 802.15-04/0249r0
Submission
May 2004
We focus only on UWB communication around the human body.
• We DO:– Develop a channel model only for waves diffracting around the body– Use the Remcom FDTD simulator.
• We EXPECT:– To incorporate waves reflecting off of nearby walls and obstacles, by
combining our results with other measurements made by the channel modeling study group:
• Consider our channel model as a distinct cluster arriving earlier than other clusters.
• For LOS models: replace the LOS component with the creeping wave component in our model.
Bart Van Poucke, IMECSlide 5
doc.: IEEE 802.15-04/0249r0
Submission
May 2004
Waves travel through and around the body.
EM waves propagate around the body via two paths:– Penetration (dielectric losses, tissues interfaces losses)– Creeping waves (diffraction mechanism)
REMCOM XFDTD software together with a complete
body model:
1 time step = 10ps
Time step 01Time step 11Time step 21Time step 31Time step 41Time step 51Time step 61Time step 71Time step 81Time step 91Time step 101
Time step 111Time step 121Time step 131Time step 141Time step 151Time step 161Time step 171Time step 181
Bart Van Poucke, IMECSlide 6
doc.: IEEE 802.15-04/0249r0
Submission
May 2004
We recorded the electric field around the body for an UWB pulse
• Transmitted a 100 ps pulse using a simple 1.5 cm dipole antenna.• The resulting pulse at a reference position 20 degrees from antenna
was approximately a 1 ns Gaussian pulse centered at 4 GHz.• All measurements made relative to this reference position.
Time step 11
Bart Van Poucke, IMECSlide 7
doc.: IEEE 802.15-04/0249r0
Submission
May 2004
Path loss depends on angle separation between antennas
Bart Van Poucke, IMECSlide 8
doc.: IEEE 802.15-04/0249r0
Submission
May 2004
Pulse is severely distorted by the human body.
90 Degree separation (with body)
Same position (free space)
Time
Time
Mag
nitu
deM
agni
tude
Bart Van Poucke, IMECSlide 9
doc.: IEEE 802.15-04/0249r0
Submission
May 2004
Status and Conclusions• We are simulating UWB communication around the
body using the Remcom FDTD simulator.
• We propose re-using measurements done by this study group to incorporate the influence of surrounding walls and objects.
• We are currently analyzing the results of our simulations:– We have recorded the path loss around the body– We observed significant pulse distortion
Bart Van Poucke, IMECSlide 10
doc.: IEEE 802.15-04/0249r0
Submission
May 2004
Future Work
• Understand underlying mechanism responsible for results.
• Incorporate simulated results into a statistical model suitable for communication system design and comparison.
