Power line communications (PLC) refers to the concept of transmitting information using the electrical power distribution network as a communication channel. This technology allows a flow of information through the same cabling that supplies electrical power. This novel idea of communication helps in bridging the gap existing between the electrical and communication network. It offers the prospect of being able to construct intelligent buildings, which contain many devices in a Local Area Network.
During the last years the use of Internet has increased. If it would be possible to supply this kind of network communication over the power-line, the utilities could also become communication providers, a rapidly growing market. On the contrary to
power related applications, network communications require very high bit rates and in some cases real-time responses are needed (such as video and TV). This complicates the design of a communication system but has been the focus of many researchers during the last years. Systems under trial exist today that claim a bit rate of 1 Mb/s, but most commercially available systems use low bit rates, about 10-100 kb/s, and provides low-demanding services such as meter reading. The power-line was initially designed to distribute power in an efficient way, hence it is not adapted for communication and advanced communication methods are needed.
PLC integrates thetransmission of communication signal and 50/60 Hz power signal through the same electric power cable. The major benefit is the union of two important applications on a single system. The data link appears 'transparent' to the user. Although the devices are connected through the power line, consumers perceive that there is a “separated” link available for data communications. Since the existing power lines are used for signal transmission, the initial heavy cost and investment for setting up a data communications system is avoided. Setting up such a communications system then involves installation of transmitter and/or receivers at appropriate points
The dissertation aims to thoroughly explore the theoretical and practical aspects of power line communications (PLC) techniques. We placed ourselves a number of goals at the start of the project.
To gain a detailed knowledge of the challenges faced by PLC techniques
To explore the theoretical and practical aspects of PLC.
To research and design a working PLC and on/off control system.
To use the design and implement a power line communications system that connects two personal computers and moreover one should be able to transmit command over the power line to switch on/off an electrical device. The PC should be able to transfer data using the power lines as their only link of communication.