Technical Topics, August 2004
BPL Update
Not in my backyard! That was the central theme of most of the entities that filed comments with the FCC opposing the deployment of BPL on HF and VHF frequencies in the USA.
In a process that began over a year ago, thousands of users of the HF and low VHF spectrum weighed in on BPL. Most of those making comments were amateur radio operators, but all users of HF including SWLs were represented.
The formal FCC comment process has now ended and it is up to the commissioners to decide what to do next. Do they charge ahead knowing it will be impossible to stuff BPL back into Pandora’s box? Do they regroup and tighten Part 15 regulations? Do they protect one service while dumping BPL interference on frequencies used by services perceived as being less important or less vulnerable? The answer should soon be known.
In its original comments NASWA suggested, that because every HF user would request special protection, the FCC should consider confining BPL to unused segments of the VHF TV band. When the NASWA prediction was borne out by the initial round of comments, NASWA decided to amplify on its initial suggestion in its reply comments.
Here is the text of the FCC reply comment filing:
The North American Shortwave Association (NASWA) represents the interests of people in the United States who rely on free access to international news and cultural programming via short-wave radio broadcasts.
NASWA filed its original comments on this NPRM on May 3, 2004. In those comments NASWA demonstrated why the FCC’s proposed procedural rule changes to mitigate BPL interference would be impractical and ineffective for protection of the international short-wave broadcasting service.
The technical feasibility of active, real-time interference mitigation has also proven ineffective in the weeks since May 3. Alliant Energy in Cedar Rapids, Iowa, using Amperion BPL technology, has been unable to eliminate harmful HF interference despite their best efforts since March to notch out interfering signals. A similar interference condition has been reported in the Raleigh, NC test area. The best efforts of these BPL providers did not eliminate harmful interference. The interference mitigation techniques, that are the basis of this NPRM, do not always work.
NASWA warned in its comments that it was likely all HF spectrum users would request special protection by the FCC from BPL interference. As predicted, APCO, The Association of Public-Safety Communications Officials-International, Inc.; ARRL, The American Radio Relay League; NAB, The National Association of Broadcasters; NAS, The National Academy of Sciences; NASB, The National Association of Shortwave Broadcasters; NASWA, The North American Shortwave Association; NTIA, The National Telecommunications and Information Administration; and several other organizations requested protection of particular frequencies and frequency bands or geographical regions (quiet zones) by BPL signals.
NASWA suggested in its original comments that BPL should be confined to frequencies above 30 MHz. NASB supported that idea. NASWA further suggested that vacant VHF TV channels would be a place where BPL could co-exist with TV broadcasting.
Organizations representing public safety agencies noted that many state and local police and fire services still use “low band” VHF allocations between 30 and 50 MHz and requested that BPL signals be prohibited from using this range. The NAB expressed concern that BPL signals would interfere with VHF TV reception and requested that BPL signals be prohibited from using frequencies above 50 MHz.
Thus, nearly all frequencies between 2 and 80 MHz would be precluded from use by BPL if the FCC were to satisfy the concerns of all entities requesting special protection. Regardless of what the FCC decides to do in response to these requests for special protection, it is unlikely that all entities will be happy with the result. The FCC is thus forced to adopt rules that will do the least harm to existing services.
In NASWA’s opinion, that least-harm solution would be for BPL to be required to use vacant VHF TV channels under carefully engineered criteria that would protect co-channel and adjacent-channel TV broadcasters. The current TV channel allocations were developed in the 1940s when TV receivers were less selective. In each major market adjacent channels were left vacant to accommodate the 1940s state-of-the-art receiver selectivity. Selectivity of today’s receivers is much improved. Today’s cable-ready TV receivers require much better adjacent channel selectivity because cable TV systems use all VHF channels.
BPL signals operating on vacant “over-the-air” TV channels would not be expected to affect cable TV subscribers. There are strict FCC rules limiting unintentional radiation by cable systems. The same tight shielding that prevents unintentional radiation from cable TV systems also protects cable TV systems from interference from outside emitters sharing the same frequencies. Responsible cable TV operators survey their physical plant periodically looking for problems. Unintentional radiation would make CATV program products freely available to nearby TV receiving antennas and would limit the ability to sell cable service.
NASWA was pleased to see the release of NPRM ET Docket 04-186 on May 25, 2004 soliciting comments on how wireless broadband services could use vacant VHF and UHF TV spectrum. If wireless broadband services that intentionally radiate can co-exist with broadcast TV signals, then surely BPL signals with some unintentional radiation can also co-exist with VHF TV broadcasting.
Because both BPL and broadband wireless services would use robust, adaptive, digital technology, it is likely they could also co-exist on the same otherwise-vacant, TV spectrum. Coordination will likely be required, but with proper engineering, frequency reuse should be achievable. Additional study is suggested.
NASWA urges the FCC to consider both of these NPRM’s together. The comments the Commission receives on the feasibility of using vacant VHF TV channels for wireless broadband services will be directly relevant to whether BPL on vacant TV channels can co-exist with TV and/or broadband wireless signals. If the outcome of the NPRM ET Docket 04-186 process shows broadband wireless can use vacant TV channels, the FCC should mandate that BPL services share these same vacant frequencies and vacate all frequencies between 2 and 54 MHz.
Since that reply comment was filed on June 22, 2004, Alliant Energy has decided to abandon its experimental operation in Cedar Rapids after trying for months to eliminate harmful interference to an amateur radio operator. The FCC did not move to shut down the utility for violation of Part 15 rules. It was only when the ARRL filed a formal complaint against the utility requesting immediate shutdown and fines for willful violation of the FCC rules that the utility, seeing the handwriting on the wall, decided to cave in. Alliant Energy also cited economic factors in making their decision.
Hopefully, there may be a trend beginning. The City of Manassas, Va. and the BPL contractor that was supposed to provide BPL service to the entire city over the municipal electric grid have decided to end their contract by mutual agreement. Manassas has now found another small company, Communication Technologies Inc. (COMTek), to risk its own capital to construct and operate the service.
The utility near Raleigh, NC, after failing to cure interference from its BPL operation, has chosen a different tactic. They simply redefined what “harmful” is. Sort of like Bill Clinton trying to figure out what “is” is, they have stretched credulity by adopting a silly definition of “harmful interference”. They have taken the official position that a mobile receiver, driving along the route of the BPL transmission lines, will not encounter harmful interference because the vehicle will soon drive beyond the BPL service area. Of course such a head-in-the-sand attitude drew plenty of reply comments from hams and public safety organizations. They pointed out that often a mobile unit is dispatched to a specific site for some emergency support. The vehicle may be required to park in close proximity to a BPL-carrying power line for an extended time until the emergency condition goes away. Others pointed out that BPL signals are carried by wires running along the roadside, so a mobile HF or low band VHF user may be exposed to harmful interference for a long time even though the vehicle is moving.
Ed Hare of ARRL recently posted the following list of BPL test sites with their current status. If you are a short-wave listener living in or near one of these places, you might want to be on the alert for new interference signals. Feel free to contact me via e-mail and I will help you determine if what you are hearing is a BPL signal.
Here is the ARRL list shown by state in alphabetical order:
- Cullman, AL (very small HomePlug system)
- Cottonwood, AZ
- Phoenix, AZ (one or two houses)
- Menlo Park, CA (not yet active)
- Pueblo, CO (not known to be active)
- Miami, FL (not yet active)
- Honolulu, HI
- Cedar Rapids, IA (shut off)
- Boise, ID
- IN - Unspecified small test, according to unconfirmed info relayed through IN
- DPUC
- Potomac, MD
- Rochester, MN (just getting ramped up)
- Cape Girardeau, MO
- Everetts, NC
- Raleigh, NC
- Williamstown, NC (not known to be active)
- Omaha, NE (not known to be active)
- Nevada - experimental license, unknown locations - no site yet identified
- Penn Yan, NY
- Solvay, NY
- Rochester, NY (utility declined to activate)
- Bowling Green, OH (not known to be active)
- Hyde Park, OH (just getting ramped up)
- Chambersburg, PA (not known to be active)
- Emmaus, PA
- Winchester, TN (not known to be active)
- Blanco, Burnet, Weimar, TX (not yet active)
- Manassas, VA
- Nelson CTY, VA
- Chelan CTY, WA
If a BPL service begins operation in your community, you need to know about it. Stay informed about what is going on in your area. One easy way to stay on top of this fast changing field is to join the Yahoo group “BPLandHamRadio”. Here people post news about all the different tests going on in the USA and announcements of new start-ups. If you believe your short-wave reception is being interfered with by a BPL service contact both the utility and the BPL service provider. Work with them to help them verify that they are causing the interference. If they try to fix your problem and fail it may be necessary to get tough by filing a formal FCC complaint. It worked for ARRL and that ham in Cedar Rapids.
It will be up to individual short-wave listeners to carry the ball. NASWA does not have the deep pockets necessary to carry your water like ARRL can afford to do on behalf of its members. In the final analysis the interference you encounter will be your problem to fight. The FCC has so far proven unwilling to help people reporting BPL interference.
Don’t look for a change in FCC commissioners to fix the problem. President Bush has publicly spoken about his enthusiastic support for BPL. The President appoints the FCC Commissioners and the Chairman. All the Commissioners, both the 3 Republicans and the 2 Democrats are on record supporting BPL. Even if President Bush loses the November election, his likely Democrat opponent has publicly advocated the rapid rollout of broadband technology. So the cheerleading for BPL will likely continue in Washington under the next administration regardless of who wins in November. It will be up to you to make as much noise as possible to your senators and representatives. The battle has only begun.
Hopefully BPL will die of its own technical and economic faults. But we can’t count on it. We must arm ourselves with knowledge about what BPL interference sounds like and who to contact in your local area if you identify interference. We must prepare for the worst while hoping for the best.
Remember that your right to listen to short-wave radio for your news is guaranteed by international radio regulations, FCC Part 15 regulations, and ultimately by the first amendment to the US Constitution which guarantees in part, “Congress shall make no law … abridging the freedom of speech or of the press; … ”.
It can be argued that the FCC is an agent of the Congress when it writes communications regulations under authority granted to the FCC by the Communications Act. When those regulations fail to protect your right to free access to the news those regulations violate the protections of free speech and a free press guaranteed by the first amendment.
At least that is my opinion. But then I am not a constitutional lawyer, I just play one on the internet and in this column. Stay tuned.