January, 2007 Doc: IEEE 802.15-07-0546-00-0ban · January, 2007 Doc: IEEE 802.15-07-0546-00-0ban Slide 3 Yazdandoost, Kohno Outline UWB Antenna in Free Space UWB Antenna on Direct

January, 2007 Doc: IEEE 802.15-07-0546-00-0ban

Yazdandoost, KohnoSlide 1

Project: IEEE P802.15 Working Group for Wireless Personal Area NProject: IEEE P802.15 Working Group for Wireless Personal Area Networks etworks (WPANs)(WPANs)

Submission Title: [The Effect of Human Body on UWB BAN Antenna]Date Submitted: [January, 2007]Source: [Kamya Yekeh Yazdandoost, Ryuji Kohno] Company: [National Institute of Information and Communications Technology

(NICT)]Contact: Kamya Yekeh YazdandoostVoice: [+81 46 847 5435], Fax: [+81 46 847 5431] E-Mail: [[email protected]]Abstract: [Discussions on the Effect of Human Body on UWB BAN ANTENNA]Purpose: [To provide an introduction of the Effect of Human Body on UWB BAN

ANTENNA]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.



Kamya Yekeh Yazdandoost, Ryuji Kohno

National Institute of Information and Communications Technology (NICT)

THE EFFECT OF HUMAN BODY ON UWB BAN ANTENNA



Outline

UWB Antenna in Free Space UWB Antenna on Direct Contact with Human BodyUWB Antenna on Direct Contact with Human Body with 2nd Substrate Conclusion



Antenna in Free Space



Aim of Design

Low Cost,Simple Structure & Small Size

Frequency Operation3.1-5.1 (GHz),

Lower Band of UWB Frequency

BW = 2 (GHz)VSWR ≤ 2

Omni-Directional PatternSatisfactory Gain

Liner Phase



Developed Antenna

Substrate

Metallic Layer

Side view of the antenna Structure

Top view of the antenna structure

25 mm

34 mm1 m

m

Substrate: FR4 (εr = 4.4 )Metal: Copper (t = 18 um)



Feed LineThe antenna is fed through a couple tapered transmission line. The tapered transmission lines have shown good impedance matching over a wide frequency range.The geometry of the taper is chosen to minimize the reflection and optimize impedance matching and bandwidth.



Prototype



Results (Free Space)Return Loss



Impulse Response (Receive Signal)Results (Free Space)



Results (Free Space)Return Loss

Frequency (GHz)

S11

(dB

)



Results (Free Space)

Frequency (GHz)

PhasePh

ase

(deg

)



Results (Free Space)Gain

Gai

n (d

Bi)

Frequency (GHz)



Results (Free Space)Radiation Pattern (dBi) at 3.1 GHz

y-z plane x-z plane x-y plane

φ= 0 φ= 90





φ= 0 φ= 90





φ= 0 φ= 90




+ + + Eθ E φ




+ + + Eθ E φ




+ + + Eθ E φ



Results (Free Space)3D Radiation Pattern

z

x

yθ

φ



Antenna on Direct Contact with Human Body



Direct Contact of the Antenna Substrate with Skin

A part of human chest wall used in electromagnetic simulation

AntennaFR4



Results (On Body, Direct Contact)Return Loss

Frequency (GHz)

S11

(dB

)



Results (On Body, Direct Contact)Phase

Frequency (GHz)

Phas

e (d

eg)



Results (On Body Direct Contact)Gain

Frequency (GHz)

Gai

n (d

Bi)



Results (On Body, Direct Contact)Radiation Pattern (dBi) at 3.1 GHz


φ= 0 φ= 90





φ= 0 φ= 90





φ= 0 φ= 90



Results (On Body, Direct Contact)3D Radiation Pattern

z

x

yθ

φ



Antenna on Direct Contact with Human Body with 2nd

Substrate



Direct Contact of the Antenna Substrate with Skin

A part of human chest wall used in electromagnetic simulation

AntennaAntenna

RH-5FR4

2nd Substrate: RH-5

t = 14 mm ,εr=1.09

tanθ=0.0004

http://www.cumingcorp.com



Results (Direct Contact, 2nd Substrate)Return Loss

Frequency (GHz)

S11

(dB

)



Results (Direct Contact, 2nd Substrate)Phase

Phas

e (d

eg)

Frequency (GHz)



Results (Direct Contact, 2nd Substrate)

Frequency (GHz)

Gain G

ain

(dB

i)



Results (Direct Contact, 2nd Substrate)Radiation Pattern (dBi) at 3.1 GHz


φ= 0 φ= 90





φ= 0 φ= 90





φ= 0 φ= 90



Results (Direct Contact, 2nd Substrate)3D Radiation Pattern

z

x

yθ

φ



ConclusionA study on the affects of human body on wearable UWB antenna has been

performed.

The antenna designed to operate in a lower band of UWB frequency from 3.1 to 5.1 GHz.

The antenna performance in a free space, close to the human body and same antenna with second substrate layer close to the human body presented.

We have shown that, the body absorbs a significant amount of the output power and changes the antenna characteristics, when an antenna placed on the surface of human body. Therefore destructively affects the performance of the system.

Particularly, the human body affected the radiation pattern of antenna and it has become directional.

Also, we presented that, adding second substrate layer can improve the antenna performance close to the body. However, the antenna radiation patterns remained directional.



January, 2007 Doc: IEEE 802.15-07-0546-00-0ban · January, 2007 Doc: IEEE 802.15-07-0546-00-0ban Slide 3 Yazdandoost, Kohno Outline UWB Antenna in Free Space UWB Antenna on Direct

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