Share Email Print

Proceedings Paper

Laser-assisted manufacture for performance-optimized dielectrically loaded GPS antennas for mobile telephones
Author(s): Oliver Leisten; Jim Fieret; Ines Stassen Boehlen; Phil T. Rumsby; Patrick McEvoy; Yiannis Vardaxoglou
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

The use of ceramic cores of high dielectric constant is an essential part of a strategy to miniaturize GPS antennas for mobile telephones. The core reduces the guide wavelength of the conducting structures on the antenna, thereby creating a need for high-resolution imaging to maintain very accurate dimensions. It is for this principal reason that a novel laser imaging technology has been developed using a positive electrophoretic photoresist and UV excimer laser mask imaging to produce the conducting features on the surface of the antenna. Furthermore, a significant process challenge in producing this type of antenna concerns the reproducibility of the right-hand circular polarization performance and the bandwidth over which this can be achieved - which becomes progressively smaller as antenna size is reduce. It is therefore a vital requirement that the antennas have the point to be tuned by a laser trimming process at an automatic RF testing station. A galvanometer controlled Nd:YAG laser spot is used to trim the conductive pattern on the top of the antenna following an RF measurement to characterize the resonant frequencies of the four helical conductors. Results demonstrate the laser imaging and trimming techniques ensure a high-speed method of guaranteeing the antenna performance. The technique is appropriate for other antenna types such as GSM, Bluetooth and Wireless LAN.

Paper Details

Date Published: 18 June 2002
PDF: 7 pages
Proc. SPIE 4637, Photon Processing in Microelectronics and Photonics, (18 June 2002); doi: 10.1117/12.470647
Show Author Affiliations
Oliver Leisten, Sarantel Ltd. (United Kingdom)
Jim Fieret, Exitech Ltd. (United Kingdom)
Ines Stassen Boehlen, Exitech Ltd. (United Kingdom)
Phil T. Rumsby, Exitech Ltd. (United Kingdom)
Patrick McEvoy, Loughborough Univ. (United Kingdom)
Yiannis Vardaxoglou, Loughborough Univ. (United Kingdom)

Published in SPIE Proceedings Vol. 4637:
Photon Processing in Microelectronics and Photonics
Jan J. Dubowski; Koji Sugioka; Malcolm C. Gower; Willem Hoving; Richard F. Haglund Jr.; Alberto Pique; Frank Traeger; Jan J. Dubowski; Willem Hoving, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?