Power Line Communication is a rapidly evolving field for data communication. Through the use of PLC technologies, electric power lines can supply both electric power and pipe for reliable communication traffic.
The residential PL has been promising and attractive communication because the entire infrastructure already exists and initial costs can be minimal. We are confined to LT (Low Voltage) segment (220v/440v) from the DT (Distribution Transformer) to the building of consumer.
PLM : Power Line Modem
AMR is a low data rate PLC application. In this application, the readings are obtained from the remote meters installed at first points of various buildings under a distribution transformer wherein a base station (PC) is located.
Each meter interfaced to a PLC modem with a unique device address. The basestation broadcasts the device address of the meter and the parameter (voltage/current/energy) to be obtained from the meter. The meter on the other hand receives the broadcast message. If the received address matches with its own address, then the current reading is sent to the base station as requested. We have designed our powerline modems based on chipsets available in the market. The chipsets we used were from Intellon .
AMR Communication Setup :
1. Communication Standards :
Commercial communication practice, over any medium is normally governed with standard specifications. There are 2 sets of standards in PLC systems :
CE Bus specification has set aside the range 100KHz – 400KHz. The Spread Spectrum Carrier (SSC) is a technique used to implement CSMA/CA
Packet networks with many users on nodes sharing the same channel. This technology is adopted by EIA as physical layer specification for CE Bus standards.
2. Security :
Due to open, insecure nature providing security service such as identify, Authentication and Message Integrity verification are examples of 2 services that are necessary for these networks. Due to low data transfer requirements and computational complexity authentication schemes are ideally suited for PL networks.
The General Electronics Corporate Research and Development Centre made a significant contribution to the CE Bus standard in what is referred to in the standard as GE Authentication and Encryption Algorithm.
3. Links for more info. on Powerlines :