Deloitte Telecom SIG: Word of the Day: Access BPL

We left off last time with Broadband over Powerline (BPL) discussing home voice/data traffic is able to be transmitted via electrical utility power lines. Today we will discuss one form of this technology.

Access BPL: a form of PLC (Powerline Carrier) that uses components of the existing electrical power grid for the delivery of broadband services. Specifically, Access BPL uses special injectors (i.e. modems and couplers) to interface the telecommunications network to medium voltage (MV) lines in the electrical distribution network. MV operates at a manageable 7,200 volts or so. The Radio Frequency carrier supporting the communications signals shares the same line with the electrical signals as they operate at different frequencies. Repeaters spaced every 300 meters or so serve to re-amplify, re-time and regenerate the signal as it travels from the utility substation toward the customer premises. The signals are removed by extractors placed just ahead of the transformers, which typically serve a number of households. Typically, the extractors bypass the transformers and bridge the communications signals between the MV lines and the low voltage (LV) (110/220 volts) drops to the premises. Alternatively, they may bridge the signal to a Wi-Fi (802.11 b/g) node that serves multiple premises through a wireless hotspot. Although Access BPL services are not widely available, a small number of utilities began offering service in 2003 and 2004, and several others have announced their intentions to do so.

In summary, there are 3 components to Access BPL:

1) Medium voltage line (MV)
2) Bypass of the low-voltage transformer in residential neighborhoods that steps down voltage
3) Low voltage distribution from the transformer to residential electrical outlets

Overall, this could be a great “last mile” alternative to DSL and Cable access when speaking in terms of delivering connectivity to rural subscribers.