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Broadband Over Power Lines vs. Radio Relayers
amaiman writes "Recently, broadband Internet access has been increasing around the country. These broadband signals, while providing Internet access to remote communities that would normally not be able to receive broadband, are causing enormous interference to the radio spectrum. This article details some of the problems, and a video available on the American Radio Relay League's (ARRL) site shows exactly how much interference the broadband power lines can cause. Detailed information is also available on the ARRL site."
But I thought that hams where saying that BPL would destroy radio communication for 100's of miles around? This video only shows the effect when they are very near the powerlines.
They also play word games by saying it is on the agenda at the FCC. On the agenda doesn't mean that they will approve it, it simply means they are looking at it.
Lastly, it doesn't help hams when hams say they will just pump out a 1kw signal to drownout the BPL signal, that action will simply result in the group with the most votes winning, and that isn't the hams.
The latest RFC don't deal with broadband over power lines any more. It's been tried, and power companies have folded over this bet.
My own power company gave up and found it more efficient to simply lay TCP/IP fiber along the new power lines instead.
No, the new thing is not TCP/IP over electricity lines, but electricity over TCP/IP lines, as detailed in RFC3251.
Shortwave radio communication over any long distance (commercial, military and hobbyist) often deals with weak signals. Each broadband power line adds to the background noise cumulatively raising the problem. One power line won't trash your TV signal (unless you are very close), but each one adds noise until all you have is snow.
Its like people talking in the background - a couple of people don't do much harm but when you try and talk across a room full of quietly talking people two things happen
1. The cumulative background noise reduces the signal
2. You turn the volume up (as the amateur radio people will have to and although entitled too don't wish too because it causes other users problems)
When you turnt he volume up, they all have to talk louder, so you get a fight between high and higher BPL power (to avoid radio wiping out internet, and higher and higher radio power for the same reason). At which point nobody can communicate usefully and lots of third parties are harmed.
HF interference isn't just an amateur radio problem either - you might well find you get 802.11 dead zones if you are near a power line using it. You may not be able to use radio controlled toys in an area with too many power lines and so on. Finally HF is essential to things like flying medical services and some rural communcation systems.
It all gets quite messy when this happens because good radio practice is the lowest possible power. The lower the power you can use the more people can use the same frequency. If everyone has to use 1KW then you'll get a lot less frequencies.
I'd also say their description of the FCC is in tune with its historical decision making - just look at the monopolisation of US commercial radio and the continued unneccessary exclusion of most small transmitters which could exist and other countries have proved are not a problem. Of course BPL background noise might well wipe out the scope for very low power radio stations too.
BTW: BPL trials in the UK (way before the US) were shelved for several reasons but intereference was a big one.
It shouldn't be insoluble - one nice property of radio is that if you can get the BPL encoding frequencies high enough then the interference problems become much less of an issue.
(PS: I defy you to find a radio astronomer who won't use expletives when asked abtut BPL..)
I'm disappointed that the FCC even cares about HAM radio operators. FEMA, NTIA, and the Department of Homeland Security have all filed with the FCC proposals 03-104 and 04-37 in favor of BPL if reasonable precautions are taken. These are the govenment agencies HAMs have been saying will be crippled if BPL is deployed. Nowhere in their replies do they spew the doomsday scenarios that HAMs are putting forward to scare people regarding BPL. HAMs love to overstate how critical they are to the communications infrastructure in emergency situations. Nothing I've read yet in reference to emergency situations can replace the following benefits in my mind: BPL can be used by power companies to provide -Intelligent Demand Side Management -Load Switching/Balancing -Fault Locations -Peak Shaving -Power Quality Monitoring -Real-Time Pricing For consumers it can provide -Video on Demand -Content -Alarm Monitoring -Smart Appliances -Broadband -InternetTelephony DS2, a BPL chipset maker has 200mbps chipsets that are working in the field now with a company working with ConEd called Ambient. My point is, even if the HAMs were completely deprived of their use of the HF spectrum (which by every government agency's accounts they won't be), I strongly believe that the benefits of a smarter power grid combined with a third major competitor for broadband outweigh the loss. I am very biased however as I'm heavily invested in Ambient, so take that into account when you read my reply. But look at the FCC replies for yourself to make up your mind before you believe either me or HAM users. Go to http://gullfoss2.fcc.gov/prod/ecfs/comsrch_v2.cgi type in 04-37 or 03-104 in proceeding and educate yourself more about the issue.
There is only a fairly small frequency band in existence that can be used for inexpensive worldwide communication, and that is HF. The reason are more or less predictable Ionosphere layers that reflect radiowaves.
Under good conditions, you can transmit halfway across the world, with just 1-5 Watts of transmission power. The Amateur Radio community knows this as "QRP" operation, and it is quite popular. So, yes, even small amounts of HF noise will go a long way to interfere with shortwave communication.
20 years ago a sizable amount of communication was still being done by shortwave (HF) radio, and anybody thinking about poisioning large chunks of HF spectrum would've been declared a raving lunatic. Every kHz of HF spectrum was (and still is) a prized posession. Look up any frequency book from the 80's and you'll see that there wasn't a Hertz of HF spectrum unallocated, and it was (and still is) tightly controlled by international agreements. For large Radio stations (BBC, VOA), it is still the only way to connect to people in dictatorships and less advanced countries.
Today, most commercial and military communication in the US has moved to satellite; Only smaller services (in the west), third world countries, radio stations and HAM radio operators use HF. Of course, why would large power companies care about other countries or the BBC news ?
The HF spectrum is still the most valuable piece of electromagentic real estate there is in the World. Purposefully injecting additional noise into the band for no other reason than to save a few bucks is a terrible mistake and shows ignorance and recklessness on a staggering level.