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FCC Proposal To Limit Access To 5725-5850 MHz Band
New submitter thittesd0375 (1111917) writes New rules adopted by the FCC will greatly limit the amount of bandwidth available in the unlicensed U-NII band used to deliver internet to rural areas. The filters required to comply with the new rules would shrink the available frequencies from 125MHz to only 45MHz. Petitions to reconsider this ruling can be submitted here and previous petitions can be found here.
According to the FCC's ruling, they did it to stop Wi-Fi signals interfering with Doppler radar systems that use the same frequencies. This doesn't sound like Big Telco or Big Cableco are behind it.
OP said:
> to deliver internet to rural areas
Article says:
> the Commission’s Enforcement Bureau found that certain models of devices certified for use in these bands were designed in a way that users were able
to disable the DFS mechanism. With the DFS mechanism inactive, the device could transmit on an active
radar channel and cause harmful interference.
and:
> Early field studies performed by the National Telecommunications and Information Administration’s (NTIA’s) Institute for Telecommunications Sciences (ITS) and FAA staff indicated the interference sources were certain unlicensed U-NII devices that operated in the same frequency band as these Federal radar systems. This interference was occurring despite the Commission’s rules that require U-NII devices operating in this band to incorporate an interference mitigation technique called dynamic frequency selection (DFS).
Oh look, people buying illegal 1Watt emitters from China and attaching them to bigass antennae to "deliver internet in rural areas" on fixed channels without DFS when regulations strictly say "nope", now crying that they're being "stepped on".
gtfo.
They're trying to protect Terminal Doppler Weather Radar, they've added restrictions on the upper band but removed the indoor restrictions on the lower (5.2ghz) band. A fair tradeoff in the opinion of someone that used to work at a WISP.
Just because you disagree doesn't mean it's not true.
With appropriate directional antennas you can actually go quite a distance (easily 5 miles) while observing all the regulations.
Just because you disagree doesn't mean it's not true.
Doppler radars cannot work on a satellite as the beam should be almost parallel to the earth's surface. They are used to remotely measure the wind speed and are useful in detecting rotating winds, thus tornadoes.
This spectrum was introduced in 1997 to augment the "last mile" cost for rural subscribers, particularly schools and libraries. It doesnt come with license fees and as such is widely used by private industry to provide internet access to paying customers who live in the middle of nowhere (many of whom dont even have cellular service.) the existing bandwidth peaks at a blistering 25mbit.
as an amateur radio enthusiast, U-NII band reform is a long time coming and private companies have a huge incentive to get you to oppose it. thittesd0375 doesnt say it, but these arent petitions you're filing either, they are official FCC proceedings and considered a complaint, which is very different than the change.org crap that shows up on slashdot one a month. holding on to this band plan and its users is an easy way for telecom companies to quietly interfere with projects that would actually help citizens like wimax and municipal gigabit/wireless. If you have any respect or concern for the people being screwed over for 25 megabit service initially intended for public education around the same time AOL was all the rage, you should probably avoid this slashdot article entirely.
Good people go to bed earlier.
They are actually trying to improve performance by reducing channels.
In particular, we noted that enhanced spectrum use may be possible when devices use a very high bandwidth and the number of usable channels is small. We also noted that the trend for U-NII devices is to operate with ever wider bandwidths such as contained in the new 802.11ac standard.
By reducing channels the spectrum can better accommodate high speed protocols like 802.11ac, which can achieve 500 Mbps in single link systems.
The same thing happened in 2.4GHz 802.11. The radios that prevail today emit over many of the legacy channel numbers to achieve contemporary throughput with "N" systems. There are only 4 non-overlapping channels used in N; 1, 6, 11 and 14. That's why most N radios won't let you pick "3" for instance.
So stop your ignorant kneejerk bellyaching, please. The original story author, this dumbass parent and you mods as well. They aren't selling the "lost" channels to Verizon or something; they're improving a regulation to make it work better. The FCC is the honest broker here.
My father in law is in a rural community. He has hundreds of acres of land and he has to use a wireless provider for internet. But he's also got dark fiber running up to his mailbox. After the cable was laid all over the county, nothing was done with it. How about taking the opportunity to push ISPs to light up that dark fiber for rural areas. If you have telephone service you should also have broadband capability.
They measure "wind" speed only if the wind happens to be carrying particulates (e.g., clouds, tornadoes). On a clear day, doppler radar will not show much, even with 50mph wind.
That may effectively put an end to all the Linux based APs (DD-WRT, Tomato, OpenWRT, etc.)
"National Security is the chief cause of national insecurity." - Celine's First Law
Seems it is about operating beyond the permitted frequency and power:
So a hardware limit to prevent out of band operation would solve the problem; while allowing the software to be controlled by the user. I've no idea how difficult a hardware solution would be, and I can see why it would be more expensive than a software one. If this has been abused, I can see why the FCC would be seeking such a ruling.
U-NNI (5 GHz) bands aren't just "a," they're also "n" and the only option for "ac." Want to run open source on an 802.11ac AP, better get one quick.
"National Security is the chief cause of national insecurity." - Celine's First Law
It would also require notching out the TDWR frequencies, instead of allowing them to be used with DFS. I suppose someone could create a fuse controlled radio chip which could be used worldwide, and fuses blown during manufacturing to limit the hardware as required, but somehow I don't think the market is big enough for that to happen anytime soon.
"National Security is the chief cause of national insecurity." - Celine's First Law
No, no need to rush.
They just stop the radio from being modifiable by software in such a way the violates the rules. The radio firmware for radios sold in the US just won't let you use those bands at too high of power.
Guess what, they ALREADY WORK LIKE THIS.
Your OSS router software can't make random changes to the radios currently, never has been able to as there are already laws in effect governing these issues.
Some devices allow you to get buy with more than you should, but thats generally an oversight, and easily fixed in the next hardware revision ... as already happens.
This isn't going to take away your precious, no need to get your panties in a knot.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager