FEMA Opposes Broadband Over Powerlines

Curmudgeon Rick writes "According to eHam.net, the Federal Emergency Management Agency has put a submission to the FCC strongly opposing the use of powerlines for broadband distribution. The report can be found here [PDF link]. IMO, vendors should let powerline broadband die. They keep defibrillating it only because of the dollars they poured in; but it is and always was a dead duck." The submission concludes: "FEMA has concluded that introduction of unwanted interference from the implementation of BPL technology into the high frequency radio spectrum will result in significant detriment to the operation of FEMA [emergency] radio systems such as FNARS."

Comments

Re:Oh well..

[jhunsake]

Satellite is expensive and still uses dial-up for upstream comm.

Yeah, five years ago it did. All satellite services now offer bidirectional satellite.

Depends...

[Svartalf]

Transmission conditions would be fine- but then you're talking about a transmitter with a lot of power compared to the BPL system. The transmitter might even jam the BPL system if it were working.

What they're worried about is reception. Over long distances, while the signals are detectable, they're really pretty weak comparatively speaking. The stuff that the BPL systems are generating are in the ballpark of the signal levels that might be detectable, so the signals from the BPL will be most likely the ones you detect.

So, you might be in a FEMA office, say like in Denton, Texas, where the power is on- but the emergency is in Corpus Christi or Brownsville. Power's out THERE because of a disaster- but the locally running BPL system's causing merry hob with your reception of the signal from that location.

Re:Depends...

[Our Man In Redmond]

Keep in mind also that hams routinely make contacts with less than 1 watt of power output. I don't know how much raidation a BPL system would throw out, but the Amateur's Antenna Rule is that the higher the antenna and the more wire you put into it, the better it is. A BPL system would be a fairly high antenna and possibly miles long. The ionosphere would propagate BPL noise as well as it would propagate any other ham radio signal of comparable power output and antenna characteristics.

It's quite usual, for instance, to have the net control for a hurricane network far away from the path of the hurricane. (In fact it's a pretty good idea for obvious reasons.) A ham in Corpus Christi in the middle of a hurricane might be able to get a signal just fine, assuming the atmospheric noise would let him and his antenna stays up, but net control in Florida might not be able to hear him -- or anyone else on the net -- due to the BPL interference.

The ARRL (national amateur radio organization) is very opposed to BPL, because it would most likely cause severe interference to radio hams. See the ARRL's BPL web page for the hams' version of the story.

Re:Oh well..

[strictnein]

Satellite is expensive and still uses dial-up for upstream comm

Not true, they have two-way satellite connections. The up-stream is generally in the 64kbit range (so, about twice that of an average phone connection (which for the upstream ~32k))

Re:Interference?

[BagOBones]

Microwave
Here in Canada our population is spread out even more than than the US.
We also seem to have the most high-speed internet options.
There are Microwave based ISPs here that offer 2 way communication at 10Mbits /s making it faster than the ADSL and Cable options. These ISPs tend to service the outskirts of the cites. The service costs a little more than ADSL or Cable.

it's all about the wavelength

[solarcardork]

Considering (US numbers) it takes about 776 miles of power line to make an efficient 1/4 wave 60Hz antenna and just 2.5 feet for 100MHz, it is fairly clear that adding high frequency content to the power lines can easily cause significant radiation.

Re:Emergency = Power outage?

[frovingslosh]

When a disaster hits and power and communication are out, hams are not just trying to talk to other hams in the local area (which they generally do on higher VHF and UHF bands anyway), they are trying to reach points that still have power. So if their signal is is jammed by crap radiating from the power lines, then vital communication can be lost.

Besides, how arogant can you be to think that hams should have their equipment sitting around useless because of lots of broadband over powerlines spectrum polution, not even be able to pratice using it or train new hams, and then expect that there will be no problem when there is a power and communication emergency just because the local broadband interference is now temporarly eliminated?

BPL FAQ

[Goody]

Here or if that gets Slashdotted, here