| dc.description.abstract | Powerline Communication (PLC) has long been established for low
data rate applications by the electric supply companies. Since 1991,
the European CENELEC standard EN 50065 has ruled the use of 3
- 148.5KHz frequency range for narrow band PLC applications. Sim-
ilar standard has been established by the IEEE in the US, where a
frequency range of 50 - 450KHz is available.
The fast growth of Internet since the 1990s accelerated the demands
for digital communication services. Furthermore, with the develop-
ment of in-home networking, there is a need to establish high speed
data links between multiple household devices. This makes PLC sys-
tems march rapidly into the high frequency range above 1MHz. Exist-
ing broadband PLC system in the 1.6 - 30MHz frequency range only
provides data rates smaller than 200Mbps. With the growing demand
of multimedia services such as High De nition (HD) video streaming,
much faster transmission speed up to Gigabits per second is required
and this can be achieved by increasing the operating frequencies.
Ultra Wideband (UWB) transmission in free space provides extremely
broad bandwidth for short-range, high data rate applications. If UWB
signals could be transmitted over the powerline channels in the high
frequency range above 30MHz, data rates up to gigabits per second
could be achieved.
In this thesis, the possibility of implementing ultra wideband trans-
mission over the low voltage indoor powerline is investigated. The
starting point is to understand the signal propagation characteristics
over powerline cables, in the UWB frequency range. Experimental re-
sults indicate that the signal degrades at an acceptable rate over the
mains cable in a scaled down UWB frequency band (50MHz - 1GHz),
which provides a potential operation band for UWB over PLC ap-
plications. Key component for the PLC system, a broadband Radio
Frequency (RF) coupler is designed and developed, to introduce UWB
signals to the transmission channel. With the channel properties and
coupling unit, extensive experimental investigations are carried out
to analyse the powerline network environment, including channel loss,
noise and radiated emission. Furthermore, theoretical channel capac-
ity and link budget are derived from measured parameters. It is shown
that the indoor powerline is a suitable media for data transmission in
the high frequency range from 50 to 550MHz in the home environment.
Finally, system level performance is analysed by modelling the Phys-
ical Layer (PHY) data transmission. The Multiband-OFDM UWB
proposal for IEEE 802.15.3a standard is used to predict the transmis-
sion performance under di erent propagation paths and data rates.
The research work conducted in this project has proven that UWB
over PLC is highly feasible for future in-home applications. With the
global promotion of smart grid applications, UWB over PLC will play
an important role in providing high speed data transmission over the
power networks. | en_US |
