Note: comments posted are strictly the opinion of the poster and not necessarily those of Fiber Planners Inc. or any other posters.
Wednesday, January 14, 2004
NTIA presentation on BPL
Michael Gallagher, Acting Assistant Secretary of Commerce and head of the NTIA (National Telecommunications and Information Administration) spoke to the Power Line Communications Association's meeting in December, 2003. A copy of his PowerPoint presentation has been posted on the web.
The NTIA manages the radio frequency spectrum allocations made to federal agencies; there are over 80,000 assignments in the 1700 kHz to 80 MHz range that might be subject to interference from BPL (broadband over power line) emission. NTIA also performs telecom research functions for the executive branch of government.
The NTIA's ongoing testing and evaluation of BPL system emissions will likely play a very influential role in any decisions by the FCC to relax Part 15 restrictions on BPL operation. Part 15 places specific limitations on radio emissions by unlicensed devices and systems such as BPL; in the event of interference, the burden of eliminating interference would fall on the BPL system operator. Vendors can have equipment laboratory tested and certified as complying with Part 15 but users of the equipment are still responsible for correcting interference issues if they subsequently occur in actual field use.
"NTIA is studying interference risks and potential means for making risks more tolerable ..."
"Risk tolerance is established by the technical and operational nature of the radio communications operations."
"Objective is to accommodate BPL with acceptable risk."
"Over 10 million BPL signal samples have been measured to define the signals radiated by BPL systems. Numerous variants of BPL deployments have been modeled to further characterize potential BPL emissions."
NTIA expects to finish Phase 1 of its study and file a report with the FCC this winter. The Phase 1 evaluation covers local interference from BPL systems operating on overhead power distribution systems. The NTIA will "recommend radiated emission limits, compliance measurement procedures, and other authorization conditions" in its' report to the FCC.
Phase 2, to be completed by the middle of this year, will look at indoor wiring and underground distribution. It will also address the potential for "long-distance interference from large scale, mature deployments of BPL systems."
Gallagher concludes his presentation by stating:
"The Administration is addressing the balance between accommodation of BPL and protection of vital federal and private services."
Based on my reading of this presentation, I expect that the NTIA will try to recommend ways to relax regulatory constraints on BPL and that these recommendations will carry considerable weight with the FCC.
The key question then for utilities considering BPL deployment then is not whether there will be any relaxation of the rules but rather how much. The extent of these rule changes could effect system operation and cost several ways. Lower system operating powers (to reduce overall emissions) would require using more repeaters spaced close together. Frequency-notching (avoiding the use of critical frequencies) would reduce the bandwidth available and require using smaller "cells" and more equipment. Some operators' equipment might be found to be more adaptable to the new regulations than others'.
January 15 update: Several people have written me since I first posted my NTIA comments above to point out that NTIA-recommended changes may involve tightening, rather than relaxing regulations affecting BPL operation. Thanks for the feedback! posted by Al Bonnyman
Wednesday, January 14, 2004#