Power line communications (PLC) allows data communications over conductors that are simultaneously used for transmission of electrical power.
PLCs work by adding a modulated carrier signal, formed by superimposing data signal over low frequency power signal. Electrical signals transmit at 50 – 60 Hz, while the data signals transmit in the order of MHz.
PLCs are also known as power line carrier, power line digital subscriber line (PDSL), or power line networking (PLN).
Narrowband PLC: They work at lower frequencies of 3-500KHz. Their data rates are low but have high range of several kilometres. They are used in the Smart Grid.
Broadband PLC: They work at high frequencies of 2 – 250MHz and have high data rates of more than 100 Mbps. They are used for short ranges. They are used for home automation.
Home Networking (LAN): The existing electrical wiring of a home can be used for LAN connection within the home, thus avoiding the need for setting up dedicated network cables. The communicating devices should have an Ethernet port. Ethernet connection is established by plugging in power line adapter into a power outlet.
Broadband over power lines (BPL): It transmits two – way signals between transformers over AC medium voltage electrical distribution wiring, and between transformers and customer outlets over AC low voltage wirings.
In-vehicle network communication: Digital signals are transmitted over direct current battery lines in vehicles.