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FCC Approves BPL Despite Interference Concerns
goosman writes "The ARRL is reporting that the FCC has approved revised Part 15 (unlicensed services) rules to specifically regulate the deployment of broadband over power line (BPL) technology. The Commission adopted a Report and Order in ET Docket 04-37 when it met in open session today. At the same time, three members of the Commission, including Chairman Michael K. Powell, specifically mentioned the concerns of Amateur Radio operators at the open meeting and expressed either assurances or hope that the new BPL rules will adequately address interference to licensed services."
Historically, amateur radio has been used as "emergency frequencies" in natural disasters. Especially when standard infrastructure (like, you know, phone and power lines) no longer work.
Finkployd
Excellent. Then you won't have any interference when you need HAM radios for emergency purposes.
Trials of this technology were abandoned in the UK in 1998/1999 (I seem to recall), due to the problem of street lights acting as transmitters, causing significant interference with emergency services transmissions.
It was accepted at the time that the cost of adding the necessary filters to each streetlight was too much to continue with the project.
Of course, technolgy has improved significantly in the last few years, maybe this has now been resolved. But it's quite possible that the system may be able to work in some areas and not in others simply because of the way your road's street lights are wired up.
Jolyon
Please read my Canon EOS tech blog at http://www.everyothershot.com
The twisted lines you saw and the twisted lines that would supposedly stop interference are two different things:
- A standard power cable is a long steel cable with an outer layer of aluminum strands twisted around it serving as conductor.
- A "twisted pair" of lines are two lines, corresponding to the signal line and the return path, that are twisted around each other. The idea is that if the same signal travels in both directions, the lines will each generate an equal but with opposite sign EM field (which is what causes interference), and these two fields will effectively cancel eachother out.
Unfortunately, if you twisted power lines, you'd need insulation tens of centimeters if not meters thick to prevent arcing. High voltage lines can run up to 400kV, and standard insulators between those and the cable towers are a good 3 or 4 meters long...
Jw
To my knowledge, every single trial of BPL in the UK has been abruptly cut short by legitimate complaints about interference - people not being able to watch digital TV, use portable (dect) phones and especially interference with amateur radio. And yet another trial pops up, goldfish memory style, only to be cut short again. I like to call this "proof by exhaustive irrelevance." They think if there's enough evidence, it's proof that it works, even if it's proof that it's an utter failure and everyone's concerns are vindicated.
I'm horrified that the US regulator has allowed this to happen, because I know the same tactics will be used on the UK regulator, and it'll probably succeed. Guess I can say goodbye to my long range lightning storm radio detection hobby...
So, screw HAM radio, right?
<echo mike>
I guess CB Ray-dee-yo is all the communikashuns you ever needed there, good buddy!!
</echo mike>
NEVER underestimate the needs of Amateur Radio in catastrophic situations. BPL interference can propagate great distances. If there is a state of emergency in an area, even if there is no power for many miles, BPL can still affect the reception of signals coming FROM the emergency area. The receiving area, with power, would have trouble picking up the shortwave frequencies due to the BPL that will most likely be present. A lot of the popular VHF/UHF emergency frequencies, apparently not affected as much as shortwave frequencies, are difficult to use in hilly or mountainous regions.
Alas, poor US Ham! I knew him, Horatio: a fellow of infinite jest, of most excellent fancy: he hath borne me on his back a thousand times; and now, how abhorred in my imagination it is!
They're certainly born the US emergency services on their back many times: and this is how they're re-paid.
Bad analogies are like waxing a monkey with a rainbow.
http://www.uplc.utc.org/
Chris Williams clw7500nc@gmail.com
An article By UK Columnist Peter Cochrane last year give a nice list of why this technology won't work, even though it has been claimed as "Proven" many times:
- Power cables employ low-grade plastic that is unfriendly to high-frequency signals as the absorption per unit length is very high. This alone precludes transmission of high-speed data over significant distances.
- Power cables are not physically symmetrical and are therefore very effective antennas. They radiate energy from high-speed data signals which becomes a source of interference for wireless services including broadcast radio as well as emergency, maritime, aeronautical, military and navigation services. By reciprocity they also suck in energy from every local radio source which further degrades data signals.
- As signals propagate along cables they become weaker but the switching transients from washings machines, refrigerators, vacuum cleaners, electric drills, light switches and other appliances are huge, do not decay at the same rate and swamp data signals.
- Switching transients on power grids with generators going on and off line, dynamic load sharing, fault and maintenance work, all induces massive transients that also swamp data signals.
- Cable joints, transformers, power meters, the on/off nature of electrical appliances and the topology of power grids create large load changes and multiple signal reflection points. This creates a dynamic echo environment where the transmitted signal is further corrupted.
- Real time communications of any kind - whether by telephone, radio or TV - are taken out by the huge voltage transients inherent to power lines and ultimately the data rates achievable for non-real time are also very low.
- Transformers and power meters require a workaround as they present an absolute block to any high frequency signals.
" Even though they are expensive, in the end they are probably more reliable anyway in the kinds of situations where radio communication is essential."
I disagree. Ham radio operators (myself included) pride themselves in being competent masters of radio technology. We might be called amateurs but you do need to hold a license in order to participate. Amateur radio operators have a network of likeminded individuals who ensure that we are there in the case of emergencies. Preparation is important to us as well as the ability to talk to anyone, anywhere, from anywhere. We need no electricity (generators, solar power, etc) and we need little time to organize.
Ham radio operators assist the red cross and the military with communication. For more information you might want to see:
this as well as this and this.
We are the ones there, first, when shit hits the fan and communications need to be set up.
Not having broadband in certain places inside of NYC is actually less surprising than not having it in a typical suburban tract scenario. The wiring and conduiting in alot of these buildings are over 100 years old. After doing cable runs and seeing some of the superstructures of buildings in the 5 boroughs I can understand why no person in their right mind would want to pull cable unless the return was guaranteed. I'd suggest organizing the neighborhood and get the cable company in there ;).
They did some small scale testing here in Cincinnati, Ohio and the amateur radio community here did our best to watch for interference. There were two separate neighborhoods tested in and we were unable to find any interference so far but we're also not all convinced we were looking in the right places. So, on the plus side, there wasn't any blatant large scal interference from the small test but on the negative side it would have been nice if the utility company had been willing to tell us exactly where the test was being run so we could take a closer look at the lines involved. We'll just have to see. I'd wager that here in Cincinnati we'll see some quick adoption because the utility company here has already been hinting at cut-rate broadband prices to get into the market.
Michael
Actually... not likely.
The Homeland Security Dept has listed Hams as First Responders and as "essential" persons in the areas of security. HSD and FCC are both keeping this in mind.
I think one of the biggest reasons the FCC is allowing BPL is to introduce some competition to the cable and DSL companies. Right now it's pretty simple:
If you have cable TV, cable internet is probably cheaper than DSL.
If you don't have Cable, DSL is likely cheaper.
If BPL comes in under the cost of DSL for someone w/ Cable, and under the cost of a bare-copper/naked DSL line, you're seeing some major choices to be had.
~Donald / Just RTFM
Parent poster is correct, and well explained. Here's another way to look at the twisted-pair concept.
Any electrical circuit forms a loop; you can trace the current going out from the power source, through the load, and back to the other side of the power source.
For an electric power transmission line, this "loop" is the wires on the left and right sides of the power-line crossbar (OK, not all lines look like that, but the principle is the same). You can trace an imaginary line down one side of the power line and back on the other, enclosing a loop 12 feet wide and many miles long, with enormous area. This is one reason power lines are a bad idea for carrying RF signals; they make a GREAT antenna.
For radio interference, the area enclosed by this loop is an important factor; reduce the loop area, and you reduce the radiated interference. The DIRECTION of the current in the loop also counts; a clockwise loop radiates with a phase opposite that of a counterclockwise loop and can cancel it out if the two are right next to one another.
Now imagine twisting the two wires around each other; you get many very tiny loops with alternating CW/CCW directions of current flow in the loop; their net radiating effects cancel out.
Interesting note: Cross-country power lines ARE in fact twisted pairs, to prevent another interference type. At every Nth tower, you'll see the lines cross over so the left-hand line goes to the right. This results in loops of a half-mile length or so; useless for shielding from RF, but VERY important for protecting the grid from geomagnetic storms, where the Earth's magnetic field is pushed around by solar wind. Making the net loop area zero prevents the transmission line from acting as a giant DC generator and blowing out the switchgear, causing major blackouts (this happened in Canada in the 1970s, IIRC).
"My strength is as the strength of ten men, for I am wired to the eyeballs on espresso."
It has been undergoing testing and is now APPROVED in the town where I live: Manassas, VA. I have cable and am very satisfied with the speed...I think the BPL company advertises a speed that is about 1/2 what I have now. It's also less than 1/2 the monthly price, though.
And amateur radio operators won't have a chance to practice for those emergencies because the rest of the time, QRM from BPL will render the frequencies useless. Brilliant!
"Twisted pair" refers to both conductors being twisted together.
The idea is that the magnetic field (H-field) and electric field (E- field) from the one conductor, where the signal is travelling one direction, will cancel out the H and E fields from the other conductor, where the returning signal is traveling the other way, leaving no net signal at distances "far" from the conductor (where "far" is defined by the signal frequency).
In a power line, you CANNOT twist the two conductors into that kind of close proximity, as the insulator required to keep the power from going ZZAAP is too large and/or costly to deploy.
Furthurmore, one of the assertions of BPL - that by using BPL "every power plug is an Internet plug" is bullshit. The BPL signal will not cross a transformer - the transformer is designed to pass 60 Hz (US - 50 Hz in the UK) ONLY. Therefor, for the signal to pass the transformer there needs to be a device installed that takes the signal from one side, regenerates and amplifies it, and injects it on the other side.
The only "advantage" of BPL is the idea that you can carry the signal along the long haul high tension runs without extra infrastructure costs. However, that is being determined to be BS as well, as they are finding that they have to install signal repeaters every few km to boost the signal.
If the power companies want to get into the Internet business, great! Let them string fiber along the power lines - they will have MUCH more bandwidth than BPL gives them, much more reliability, much less interference to other services, AND they can apportion a section of the fiber for SCADA purposes (monitoring substations, controlling switching, reading your meter, etc. Note - that data would NOT be transiting the Internet, but would be in a seperate time slot or fiber, so it would not present a security risk.)
www.eFax.com are spammers
I've been a ham for many years (and I too shower, am under 30, and heck, I'm even married!) BPL is just a stupid idea all around. All antennas are basically some form or another of unshielded cable that's been bent to form a certain transmission pattern favorable to whatever frequency you're transmitting on. Albeit not a great transmitter, power lines are elevated unshielded cables, which look suspiciously like antennas covering the entire US.
Now, although I shudder at the thought of BPL's horrible interferrence, I do have a plan if it gets implemented. [evil grin]BPL works on unlicensed spectrum, under part 15. Under the part 15 rules, someone transmitting licensed under part 97 (amateur radio) can legally cause interferrence to the part 15 device. So basically, I'm legally allowed to pump my 2000 watts and not care if everyone's BPL stops working.[/evil grin]
With that said, its time to go read the new BOFH.
Well, here's a pretty good thesis on the topic:
Amateur Radio and Innovation in Telecommunications Technology The summary is "a hell of a lot", and if you want a comprehensive list, read the thesis.
It won't work that way. If BPL interferes with ham radio, the number of operators will decrease below the crticical mass necessary to provide emergency communications, worldwide.
Here's why:
BPL produces interference across the entire spectrum of "high frequency" (3-30Mhz) radio, and a little above and below in fact. The HF frequencies have special properties (on this planet, at least) of being reflected around the world by the ionosphere. A tiny sliver of these frequencies are used by amateur radio operators, but there are litterally thousands of other kinds of licensees worldwide.
BPL power lines radiate this interference, and when the ionosphere is highly reflective, the interference will be sent around the world. Since the FCC denied the request to have the BPL systems transmit identification, there won't be any way for anyone to identify which BPL installation is causig interference, since it might be halfway around the country, or halfway around the world.
There are BPL systems that don't use HF radio waves, but in all the rush to "Step 3: Profit" these technical issues have been ignored, and the comlpanies with the best lobbiests have won.
Not just the DOD, but other government agencies: SHARES, the HF interoperability communications group, which includes many MARS stations, has this to say:
2. SHARES RESOLUTION ON BROADBAND OVER POWER LINE (BPL) - THE SHARES
HF INTEROPERABILITY WORKING GROUP HAS PASSED A RESOLUTION EXPRESSING
STRONG CONCERN OVER THE FCC'S PLAN TO IMPLEMENT BPL. INDIVIDUAL
SHARES ENTITIES WILL TRY TO GET STATEMENTS ON THE RECORD DURING THE
45-DAY PERIOD FOR COMMENTS ON THE NOTICE OF PROPOSED RULE MAKING
(NPRM). HERE IS THE RESOLUTION:
QUOTE
WHEREAS,
THE SHARES HF INTEROPERABILITY WORKING GROUP IS THE DESIGNATED
REPRESENTATIVE ACROSS ALL UNITED STATES GOVERNMENT ENTITIES FOR
ADVOCACY AND EXPERTISE IN CRITICAL HF COMMUNICATIONS AND
INTEROPERABILITY, AND
BROADBAND OVER POWER LINE (BPL) EVIDENTLY PRESENTS A SIGNIFICANT
ADVERSE IMPACT TO HF BAND AND EMERGENCY COMMUNICATIONS, VITAL TO
HOMELAND SECURITY AND DEFENSE (HLS AND HLD),
BE IT RESOLVED THAT,
THE SHARES HF INTEROPERABILITY WORKING GROUP IS DEEPLY CONCERNED
ABOUT, AND STRONGLY OPPOSED TO, EITHER ACCEPTANCE OR DEPLOYMENT OF
BPL UNLESS IT CAN BE CONCLUSIVELY DEMONSTRATED IN PRACTICE THAT BPL
WILL HAVE NO ADVERSE IMPACT TO HF RADIO ROUTINE AND EMERGENCY
COMMUNICATIONS UNDER OPERATIONAL CONDITIONS, INCLUDING NORMAL THROUGH
CRISIS.
THE SHARES HF INTEROPERABILITY WORKING GROUP RECOGNIZES THE
NUMEROUS FOREIGN GOVERNMENTS WHO HAVE REJECTED THIS TECHNOLOGY, AND
STRONGLY ENDORSES THE WELL FOUNDED POSITIONS EXPRESSED BY FEMA,
ARINC, ARRL, AND NUMEROUS OTHERS OPPOSING THIS DESTRUCTIVE
INITIATIVE.
THEREFORE, THE SHARES HF INTEROPERABILITY WORKING GROUP URGES THE
DEPARTMENT OF HOMELAND SECURITY (DHS) TO MOVE STRONGLY TO PREVENT THE
IMPLEMENTATION OF BPL.
UNQUOTE
from http://navymars.org/national/cmi/CMI10-04.TXT
A google search will turn up a few hits on the subject.
So, basically in a nutshell:
You don't use HF, don't need it, and don't know any service that does, so screw them.
Pretty shortsighted and impressively incomplete view of this problem. Not all communications are local, which is what every VHF/UHF method you mentioned is. HF is in ONLY radio-based communication system that provides global coverage without needing substantial infrastructure such as satellites, etc.
Um, lemme see here.
Bucks County Rescue Squad:
45.96
46.0
47.46
Third District Volunteer Hose Company:
46.06
46.1
46.12
46.14
46.20
46.24
46.30
Quakertown Fire Department
46.1
I could go on. This was a ULS search of a few towns in Bucks County with licensed emergency services in the 40-49 MHz range. I'm sure there are hundreds of others in that same range. THEY would all get clobbered by BPL just as HF amateur operations would.
BPL will affect EVERY licensed service between 2 and 80 MHz, including thousands of public safety radio systems in rural regions of the country -- just where BPL is being touted as the Best Thing Since Sliced Bread. These are the areas where BPL will wreak havoc on radio systems belonging to sheriff's offices, rescue squads, fire departments, the electric companies operations themselves, school bus operators, construction firms etc, etc.
Does YOUR county have the budget to replace their trusted and working radio system with some POS trunked 800 MHz "solution" that won't work over long distances? Multiply that by every rural county in the country.
BPL will kill ham radio, yes, but it will literally kill PEOPLE once police, fire and rescue radio systems are rendered useless.
Please, PLEASE may I be wrong!
Cheers, Peter, W2IRT
AMA=Academy of Model Aeronautics http://www.modelaircraft.org/Comp/Competition.htm AMA is watching this as model aircraft uses 72 MHz for most modelers. There are some HAM modelers, but obviously you have to have a license.
Nope, the power lines act as an antenna and it works both ways. It has been proven a 4W CB (legal for anyone to operate) can kill BPL signals from 60 ft away amagine what the QRO guys with their kilo-watters will do. Unfortunatley there are already FCC regs on hams pointing out there are limits on unintentional (or intentonal in this case) interference. This will limit operating times allowed for the station.
So, these are hardly Broadband over Power Line- there are virtually no RF emissions from these very low bandwidth (i.e. the opposite of broadband) systems. Because of that, though, they don't require repeaters, and they generally go through transformers, etc. (although TWACS is notorious for the periodic "tweaking" required).
What the hell are you talking about?
In all my days of hamming, I've never heard anything about that. There are rules about how far the antenna has to be away from people, and keeping people out of a zone close to a high power antenna, but a simple tower does that pretty well.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
As the parent mentions, VHF and UHF frequencies are primarily only good for relatively local communications, so the HWN operates on HF. (Primarily on 14.325 Mhz, for anyone who cares to listen in.) If BPL were deployed all around the country, yes, the folks in Florida wouldn't have had any problem receiving signals. Unfortunately, the folks trying to listen to them (who were in non-affected areas) would not be able to hear them because of local BPL interference.
There's a bit more to it than that. While we hear alot about amateur radio being affected, and the amount of concern being voiced, it goes well beyond the HAM operators.
The affected radio spectrum is quite broad, and the amount of spectrum allocated to the amateur service (HAMS) is only a small part. In the same bands are various other services including a large amount of commercial and government frequency allocations. They will not be immune to the interference potential that has been tested and measured by the amateur radio community in the various trial areas.
Let me add that HAMS aren't opposed to BPL just to be difficult, but because there are numerous problems with the technology and there are other good (better) but underdeveloped alternatives. The field trials done so far have shown that it is very difficult to eliminate harmful interference to the areas of the radio spectrum involved.
For more information about BPL and the concerns of amateur (and by extension other) radio services, see this FAQ; it is perhaps the best discussion of BPL and the issues around it I have read. Also, you can check the ARRL, which has a very good discussion of the topic.
I would further note that those like me who pursue the amateur radio hobby are not unlike many of those who read slashdot, who pursue computers as not just a profession, but also as a hobby. I have seen many argue about changes to computing platforms that would restrict or possibly eliminate our abilities to pursue the computing hobby (e.g., palladium).
Emergency services was ALL coordinated by ARES for that incident. And they had base stations running on-site that afternoon.
Cell-phones were useless on-scene, the system was overloaded.
FDNY's own radio system couldn't handle the traffic of the event itself while it was happening, just before the buildings came down. They didn't have enough frequencies allocated to deal with the problem.
But with BPL, all the houses using BPL in Jersey would have been interfering as well. The frequencies used, when radiated from the wires, bounce all over the place, and travel great distances, which means that even 100s of miles away, you get noise that you didn't use to have.
In which case the HAM radios will work.