Doctor's Theses (authored and supervised):

F. Bektas:
"Investigation of Antenna Diversity Techniques for Bluetooth Communication";
Supervisor, Reviewer: A.L. Scholtz, A. Goiser; Institut für Nachrichtentechnik und Hochfrequenztechnik, 2003.

English abstract:
This thesis aims to improve performance of Bluetooth communication in industrial
and o ce environments by using antenna diversity techniques.
The motivation for this work is the fact that Bluetooth communication in factories
can reduce the use of cables and is in some cases a good alternative to wired connections.
When transmitting or receiving information from rotating and moving
machine parts, it is of great advantage to use wireless communication. Another
type of application is an autonomous guided vehicle, which is dependent on some
sort of wireless communication for communicating with surrounding machines. In
the future, machines assembling products might be able to communicate with the
product without physical connection during the assembly sequence, performing
tests and downloading software to the products.
Presently, Bluetooth is the fastest growing short range wireless communication
technology. It operates in the 2.4 GHz ISM-band and is based on a frequency
hopping physical layer. The signal transmission via a radio channel is a ected by
path loss, narrow and wideband fading, and co-channel-interference. With Bluetooth,
the packets transferred consecutive in time do not use the same frequency,
thus avoiding the drawbacks of narrowband transmission. The link performance
depends on the fading of the individual channels occupied. Therefore all methods
of improving the physical layer have to be frequency agile. As such an approach,
in course of my thesis the rst Bluetooth antenna diversity demonstrator was
In order to investigate the performance of Bluetooth antenna diversity, extensive
experimental investigations have been done. It was shown that the e ects
of multipath and fading can be combated to a large extent by antenna diversity.
Therefore, antenna diversity was con rmed to be a powerful technique for improving
the quality of Bluetooth links so that Bluetooth communication can be
used in industrial applications.

Created from the Publication Database of the Vienna University of Technology.