G3-PLC protocol

The G3-PLC protocol developed and maintained through the G3-PLC alliance is a Power line Communication technology which has recently been established a new standard for wired communication through existing power cables.

Even though power line communication has been used for long time in different areas of application, the G3-PLC protocol integrates the most recent features of modern protocols and in particular the most advanced modulation technologies such as orthogonal frequency-division multiplexing (OFDM).

As a modem technology, the G3-PLC is specified to use dedicated frequency band and in particular, CENELEC-A, -B -C, FCC and ARIB which allow to qualify G3-PLC as narrow-band Power Line communication (NB-PLC).

The effective data rate can be up to 250KB/s while the range of communication is in kilometer range.

Beside the few above characteristics related to the physical layer of the protocol, the G3-PLC technology also specifies MAC layer which provides useful features such as plug and Play network management, time domain collision management, mesh network architectures. The Transport and Network layer of G3-PLC associates the MAC layer to IPV6 and allow Internet based system management and application.

Primarily specified for Smart grid and metering applications, the overall structure and performance of G3-PLC makes it usable as a standalone protocol for a wide range of application where reliability, robustness and long range are required.

As G3-PLC is an open standard it is continuously maintained by the G3-PLC alliance and can be implemented freely for any kind of applications. The IPV6 compatibility allows to link applications with the world of Internet and, hence, must be considered as a possible pillar of IoT expansion and has such fundamental components of Artificial Intelligence implementation.

Renesas Electronics is a member of G3-PLC alliance and has developed a solution commonly named Cool Phoenix which feature the G3-PLC protocol. The solution comprises a modem IC (R9A06G037) with the complete software stack.

Detailed information can be found on Renesas PLC modem webpage

KNX Protocol

KNX is an open standard  for commercial and domestic building automation. KNX devices can manage various types of devices integrated inside building. Introduced at the beginning of 2000s, KNX has been established as one of the mosty common network for building automation.

KNX protocols currently supports 4 different types of physical layers.

  • KNX TP: Twisted pair wiring
  • KNX PL: Power-line networking known as PL110
  • KNX RF: Radio frequency
  • Ethernet (also referred to as EIBnet/IP or KNXnet/IP)

Following the market trend, KNX association is currently preparing KNX IoT which aims to be a full IP based protocol.

KNX Protocol Over G3-PLC

With the trend toward energy efficiency and green design of commercial buildings, the need for connected equipment’s is significantly increasing. Meanwhile commercial buildings structure requires long distance communication and often includes facilities which are only accessible through power cables especially when it is about building renovation and upgrade.

Power Line Technology allows to extend automation using exiting power cables and thus can significantly reduce system cabling cost.

Considering the advantages of G3-PLC in terms of communication distance performance and usability as an open standard, Renesas has considered to link between KNX/IP and the G3-PLC.

As a proof of concept, Renesas has created a network as described on the below figure.


Demonstration of KNX Protocol Over G3-PLC

Exhibiting at Embedded World 2019


A KNX switch connected with twisted pair (TP) to a KNX IP router controls a KNX node which is receiving KNX telegram through PLC. The interconnection between KNX IP and IPV6 is realized with a Network Address Translator (NAT).

Both NAT and KNX node are implemented on Renesas Synergy platform (S7G2) combined with Renesas OFDM PLC software modem (R9A06G037).