compact planar ultra wideband antenna for on-body applications.docx

8/14/2019 COMPACT PLANAR ULTRA WIDEBAND ANTENNA FOR ON-BODY APPLICATIONS.docx

1/5

COMPACT PLANAR ULTRA WIDEBAND ANTENNA FOR ON-BODY

APPLICATIONS

BACKGROUND OF RESEARCH

As wearable communication is developing, the demand of flexible fabric antennas is also

mounting. Flexible, conformal antennas are essential to provide an unobtrusive solution. For

these flexible antennas, textile materials form interesting substrates, because fabric antennas can

be easily integrated into a piece of clothing. These textile antennas can be constructed using

ordinary fabric as dielectric and e.g. conductive tape or fabric as conducting elements [1, 2].

Recently, there has been growing interest in the antenna community to merge between wearable

systems technology, Ultra-Wideband (UWB) technology and textile technology. All these

together have resulted in demand for flexible fabric antennas, which can be easily attached to a

piece of clothing [3].

UWB offers good penetrating properties that could be applied to imaging in

medical applications; with the UWB body sensors, this application could be easily reconfigured

to adapt to the specific tasks and would enable high data rate connectivity to external processing

networks [4]. It is interesting to note that small ultra wideband (UWB) antennas are also

demanded for some medical applications recently. One of the medical applications which require

the UWB antennas is the microwave imaging of breast cancer. This imaging modality transmits

lower power short microwave pulses (tens picoseconds to nanoseconds) into the body and detects

the differentiated scattering due to the dielectric contrast between malignant and health tissues. A

UWB compact antenna array is employed to conduct a 3D scanning through a so called digital

beam forming in space-time domain [5]. In order to achieve high detection resolutions and good

clutter rejection, the antennas with an impedance bandwidth 4-10GHz are usually employed as

the elements in a condensed antenna array. So, small and low profile directional UWB antennas

are desirable for this application. In addition, the antenna needs to have good radiation


2/5

characteristics, i.e. consistent patterns over the entire operating bandwidth and good time-domain

characteristicsminimal pulse distortion [6].

A wearable antenna is attractive for military purposes because it is invisible,

allowing the radio operator to hide from the enemy. A radio system with a built-in antenna doesnot require time to deploy the antenna and does not inhibit mobility. In addition, there is less

possibility of damage from the obstacles in an urban environment situation, compared with the

conventional antennas used in the military devices [7, 8]. Like other small antennas for wireless

communications, low profile and reasonable efficiency are usually specified for the wearable

antenna. In addition, for user comport and to make the clothing flexible, the antenna shape needs

to follow the user's body curvature. Operational reliability is especially important for military

applications and antennas must perform even when covered by ice, soil or mud. Ultra-wideband

communication technologies have the potential to provide a variety of applications, such as radar

imaging (below 960 MHz or 3.1-10.6 GHz), surveillance (1.99-10.6 GHz), and high-speed data

transmission systems (3.1-10.6 GHz) including RFID and sensor networks [7, 8, 9]. Therefore, it

still remains as an engineering challenge to design suitable UWB antennas for these applications.

OBJECTIVES

Main objectives of the proposed work include:

To determine the feasibility of designing ultra wideband antenna from textile substrate. To investigate the enhancement of the bandwidth over other types of cloth materials. To utilize textile materials for the development of flexible wearable systems, which has

been rapidly demanded in wireless devices.


3/5

SCOPE OF STUDY

This study will focus on the performance improvement in terms of bandwidth for the ultra

wideband antenna designed using jeans as a substrate.

RESEARCH METHODODLOGY

The work will be divided into two phases:

Phase I

This phase will be focusing on the previous works which study the performance of wearable

antennas using different fabric materials as substrates.

Phase II

This second phase will focus on simulation and fabrication of the proposed design.

Data Analysis

Different available methods will be used to analyze the data collected and available commercial

software will be employed to simulate and design the proposed model.


4/5

Expected results of the study

It is expected that this research will produce results that will help in:

1. Investigating different techniques for the design of the antenna in order to achieveoptimum performance desired in specific applications.

2. Providing a clear insight of the feasibility of utilizing textile materials in makingantennas substrate.

3. Measuring the level of bandwidth enhancement of ultra wideband antenna with jeanssubstrate properties.

References

[1] Nevin Altunyurt, Madhavan Swaminathan, Venkatesh Sundaram, George White, Conformal

Antennas on Liquid Crystalline Polymer Substrates for Consumer Applications,Proceedings of

Asia-Pacific Microwave Conference, Dec. 2007.

[2] Mai A. R. Osman M. K. A. Rahim, M. Azfar. A., K. Kamardin, F. Zubir, and N. A.Samsuri,

Design and Analysis UWB Wearable Textile Antenna Proceedings of the 5th European

Conference on Antennas and Propagation (EUCAP),2005.

[3] Mai A. R. Osman, M. K. A. Rahim, M. Azfar, N. A. Samsuri, F. Zubir, and K. Kamardin,

Design, Implementation and Performance Of Ultra-Wideband Textile Antenna Progress In

Electromagnetics Research B, Vol. 27, 307-325, 2011

[4] A. Alomainy, Y. Hao, X. Hu, C.G. Parini and P.S. Hall, UWB On-Body Radio Propagation

And System Modeling for Wireless Body-Centric Networks, IEE Proc.-Commun., Vol. 153, No.

1, February 2006, pp. 107-114

[5] X. Li, et al, C. Hagness, An overview of ultra-wideband microwave imaging via space-time

beamforming for early-stage breast-cancer detection,IEEE AP-S Magazine, vol. 47, no. 1, 2005.


5/5

[6] X. Chen, J. Liang, S. Wang, Z. Wang and C. Parini, Small Ultra Wideband Antennas For

Medical Imaging, Loughborough Antennas & Propagation Conference, 17-18 March 2008,

Loughborough, UK.

[7] J. E. Lebaric, "A Ultra-Wideband Conformal Helmet Antenna," Microwave Conference 2000Asia-Pacific, vol. 1, pp. 1477 - 1481, Dec. 2000.

[8] J. E. Lebaric, "Ultra-Wideband, Zero Visual Signature RF Vest Antenna for Man-Portable

Radios,"MILCOM2001, vol. 2, pp. 1291 - 1294, Oct. 2001.

[9] E. C. Kohls, "A Multi-Band Body-worn Antenna Vest," IEEE APS 2004, vol. 1, pp. 447-450,

June 2004.

compact planar ultra wideband antenna for on-body applications.docx

Documents