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FCC Rule Cuts Bandwidth For 72-Mile 802.11b
sonamchauhan writes "This Computerworld article reported a 72-mile 802.11b wireless link (discussed in
this Slashdot story). Now a Computerworld followup story is reporting the link power has been reduced by 75% to comply with FCC regulations for the 2.4-GHz band -- reducing the link's throughput from 1 Mbps to 300 Kbps. The owner is reported saying that: "any violation of the power limits was unintentional and resulted from the fact that the personnel working [on it] primarily have expertise in computers and not radio technology.""
These guys manage to create a 72-mile wireless link, truly an impressive feat, and do it with mostly computer guys? I'm not exactly certain, but it seems to me like they would have contacted a radio engineer at some point during the construction to assist them. Continuing with this hypothesis, shouldn't the radio engineer know the FCC guidelines and at least mention them so they wouldn't have to adjust the power?
You zap the moderators with a wand of humor! The moderators resist!
300Kbps free transmission for 72 miles is fine in my book.
cat
If you don't regulate it, people go nuts. People decide they need to broadcast at 25,000 watts from their garage. Frequencies get jammed up so bad that nobody can talk. Nobody wants that, so we have a government agency to keep it under control.
--
the strongest word is still the word "free"
The FCC doesn't pass regulations for no good reason. , so as long as folks use after-market antennas and no one files any complaints, the FCC isn't looking to imply cut back on allowable bandwidth. Wide bandwidth spectrum can be used by many users for diffeent reasons. For example, in urban areas, some of the users may be hospitals utilizing heart monitors.
Credentialism is bad.
"Oh, it's ok. You don't have to wear a condom. I'm a professional. I do this all the time."
- Yeah, uh-huh.
The owner is reported saying that: "any violation of the power limits was unintentional and resulted from the fact that the personnel working [on it] primarily have expertise in computers and not radio technology." That says it all. A bunch of computer people playing with RF; no knowledge of Part 15 rules, no concept of RF. Really, if the FCC is going to assign new frequencies for wireless networking, we owe it to ourselves to become acquainted with the technology and the rules thereof. The last thing that anyone needs is to turn 802.11 into another RF wasteland like CB radio.
What about those who can teach? :p
Any sufficiently well-organized community is indistinguishable from Government.
And I gotta get down to 7-11 before they outlaw pringles cans!
Pringles can antennas are already illegal. They are unapproved by the FCC. I still can't believe that the FCC is unwilling to free up some space in the spectrum. If they could make just one 1-gigahertz wide band in the 10-50 ghz range unlicensed, that would really expand the opportunities for wifi. (That frequency would make it hard to transmit between rooms in houses. The 2.4 ghz is better for that. But it would have no problem going a mile or two over the air with enough power, provided there isn't any fog or anything.)
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
OK I'll bite....
There is a very good reason for keeping the 2.4 GHz stuff at a low power.
The equipmend produces various frequencies some of which are in the frequencies the device is intended to transmit, others outside the allowed bandwidth are not, but they are so small that they don't do any harm. But when you go boost the power these unwanted frequencies will also get amplified (and in some cases they will get even more amplified then the intended frequencies).
What you get is a device that is jamming other things on frequencies you didn't even knew it was transmitting on.
802.11b devices have been tested and approved for use with a certain maximum output power, they used them for something they were not approved for for a good reason.
How do you know they were not interfering anybody, if that is the case how did the FCC ever found out about it??? Appearantly they were not completly 'out in the boonies' were they?
Jeroen
Secure messaging: http://quickmsg.vreeken.net/
All you need is a ham radio license and to reclassify this gear as part 97. You can then have up to 100W into the antenna and ERP much higher. Check this link: http://www.qsl.net/kb9mwr/projects/wireless/Ham_Et hernet_GBPPR.pdf to find out more. If this is just expermintation and has nothing to do with business then this would be what they need.
(make sure you check out the section of power limits in that above link, 100W at 2.4Ghz into 24dBi dish = 25118.8 W EIRP and still perfectly legal. The FCC makes the rules but luckily they make it easy to do what these people want to do, again if its not business related that is.
-Tom