PLC

Introduction

Communication technology that enables sending data over existing power cables. This means that, with just power cables running to an electronic device (for example) one can both power it up and at the same time control/retrieve data from it in a half-duplex manner.

power-line carrierpower-line digital subscriber line (PDSL), mains communicationpower-line telecommunications, or power-line networking (PLN).

Power line communication (PLC) uses existing electrical wiring, whether in a building or in the utility grid, as network cables, meaning they also carry data signals. It can be a means of extending an existing network into new places without adding new wires.

Computer could be wired to a router as follows: an adapter is connected to a router of an existing wired local-area network, via its network port. A second adapter is connected to an Ethernet-ready device like a computer. When both adapters are plugged into their wall sockets they will have a network connection via the electrical wiring in between the two wall sockets being used.[8] Some networking devices, such as routers or switches, also have power line connectivity built in. This adds no new wires since they need to be plugged into the wall to operate anyway.

The power line is transformed into a data line via the superposition of a low-energy information signal to the power wave. Since electricity is 50 or 60 Hz, data is transmitted at least 3 kHz to ensure that the power wave does not interfere with the data signal.

 

Technologies & Features

TYPES OF PLC

  • Narrowband in-house applications: where household wiring is used for low bit rate services like home automation and intercoms.
  • Narrowband outdoor applications: these are mainly used by the utility companies for automatic meter reading and remote surveillance and control.
  • Broadband in-house applications: mains power wiring can be used for high speed data transmission for home networking.
  • Broadband outdoor applications: outdoor mains power wiring can be used to offer broadband internet access.

Why PLC!

  • 60%+ U.S. homes have Internet access & 10% broadband (PLC)
  • Inaccessible and costly
  • PLC = No new wires:

oEmerging Technology

oUse of Power grid for communication

oExtensive infrastructure

  • “Every” building

Features

  • PLUG & Play PLC networking protocol
  • Other services (in the house)
  • In-place entertainment
  • Internet appliances

Electromagnetic Compatibility

  • Power lines are leaky: radiate high-frequency electromagnetic signals
  • Interferes with nearby wireless devices
  • Need filters to prevent leakage
  • 802.11b wireless network protocol (WiFi)