There
is a revival of interest in Digital Power Line (DPL) communications.
Such systems deal with the utilisation of electrical wiring networks for
signal transmission. This technology makes it possible to transmit and
receive text and image data at high data rates without the further
installation of cables or other expensive equipment.
The very complex
transfer characteristics of the electrical power network and the amount
of interference determine the overall performance and quality of a
system. Although power line communication has been under investigation
for over 50 years, interest has been rekindled during the past two
decades with the advent of new technologies.
My research reveal
that the application of DPL
techniques to wide bandwidth multimedia communications
is
possible with suitable
‘signal conditioning’ and
by
adapting the modulation and coding scheme to line conditions, an
increase in data throughput would be forthcoming.
The aim of this research was the investigation, design and
implementation of DPL technology in military and commercial marine
applications, particularly the provision of a wide variety of digital
facilities for the conveyance of command, control and communication
information. In order to transmit such multimedia information
successfully over a vessel's power line at high speed (over 1Mb/s), a
coding and modulation scheme (e.g. a hybrid OFDM/FEC scheme) deployed
that combines the efficiency of a compressed protocol with the
reliability of a powerful error control system.
This project is investigating several media types to be employed for
message communication, ranging from simple text to still and moving
images. Existing still-image and low-rate video coding methods will be
tailored, with desirable methodologies being combined with innovative
unequal error protection schemes to produce an adaptive, robust
transmission system. The emphasis will be placed on practical testing
throughout the program.
Plots showing fundamentals at 3.33 MHz and 8.25MHz
