Design and Characterization of Purely Textile Patch Antennas

• Published in: IEEE transactions on advanced packaging Vol. 29; no. 4; pp. 777 - 788
• Main Authors: Locher, Ivo, Klemm, Maciej, Kirstein, Tnde, Troster, Gerhard
• Format: Journal Article
• Language: English
• Published: Piscataway, NY IEEE 01-11-2006; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna feeds; Antennas; Applied sciences; Bends; Bluetooth; Computers, microcomputers; Conducting materials; conductive textiles; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Exact sciences and technology; Fabric antennas; fabric substrates; Frequency ranges; Hardware; Microstrip antennas; Patch antennas; Shape; Sheet materials; Specifications; Studies; Textiles; Wearable computers; wearable computing; Performance evaluation; conductive textiles; Printed antenna; Fabric antennas; fabric substrates; wearable computing; Microstrip line; Transmission line; Wearable computers; Sheet resistivity; Manufacturing process; Microstrip antennas; Antenna feeds; Plane antenna; Electrical characteristic
• ISSN: 1521-3323; 1557-9980
• DOI: 10.1109/TADVP.2006.884780

In this paper, we present four purely textile patch antennas for Bluetooth applications in wearable computing using the frequency range around 2.4 GHz. The textile materials and the planar antenna shape provide a smooth integration into clothing while preserving the typical properties of textiles. The four antennas differ in the deployed materials and in the antenna polarization, but all of them feature a microstrip line as antenna feed. We have developed a manufacturing process that guarantees unaffected electrical behavior of the individual materials when composed to an antenna. Thus, the conductive textiles possess a sheet resistance of less than 1Omega/squarein order to keep losses at a minimum. The process also satisfies our requirements in terms of accuracy meeting the Bluetooth specifications. Our investigations not only characterize the performance of the antennas in planar shape, but also under defined bending conditions that resemble those of a worn garment. We show that the antennas can withstand clothing bends down to a radius of 37.5 mm without violating specifications