Laser Assisted Manufacture for Performance Optimised, Dielectrically Loaded GPS Antennas for Mobile Telephones

TitleLaser Assisted Manufacture for Performance Optimised, Dielectrically Loaded GPS Antennas for Mobile Telephones
Publication TypeConference Paper
Year of Publication2002
AuthorsLeisten, O, Fieret, J, Boehlen, SI, Rumsby, PT, McEvoy, P, Vardaxoglou, JC
Conference NameSPIE International Optical Design Conference 2002
Pagination397-403
Conference Start Date18/06/2002
PublisherSPIE
Conference LocationTucson, AZ, USA
ISSN Number0277 786X
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.

Notes

https://www.researchgate.net/publication/228804193_Laser_assisted_manufa...

URLhttp://spiedl.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=PSISDG004637000001000397000001&idtype=cvips&prog=normal
DOI10.1117/12.470647
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