I'm obviously missing something, so please fill me in.
According to what I see, the ISM band stops at 5875.
The highest wifi channel is 165; 5825 center, 5815-5835 total channel width.
Discounting the fact that amateur radio is a secondary allocation on all the bands we're using...
Why aren't channels 176 & 177 listed as amateur only on the AREDN channel image (#2) that scrolls on the main page?
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5GHz Channels
Wed, 04/05/2017 - 16:31
#1
5GHz Channels
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K0SPA,
[ touched up to add supporting doc and correct a freq. ]
There are multiple licensed band edges in play here. I'm trying to recall, but I think the chart is ether based on how much energy is allowed past the band edge and/or the definitions based on max center freq for the signal and signal bandwidth allowed.
wifi or u-nii-3 or part 15.407: ends at 5825
part 15.247: 5825 to 5850 (and is being redefined to combine same rules with part 15.407, but not yet there)
ISM: ends at 5875
Note that ch 165 in part 15.407, at 20Mhz channel, is outside the upper edge too in the same way ISM channels are shown on the chart. I've been looking into this part 15.247 allocation and found the following:
1) A device has to be certified to meet these different rules of part 15.247 to be operating in this 25Mhz area. Many (most?) ubiquiti devices do not have this certification, but can operate in this area. UBNT marketing specs give fine print that only devices with a special FCC identifier are supported up to 5850.
2) WISP operators can operate in 5825 to 5850 with the proper certified equipment in part 15.247. We share a tower site with a WISP operator using ch 168 in this range. But it is highly suspicious because they have changed the wifi MAC address so that you cannot determine the hardware vendor (a portion of the MAC address is assigned to specific vendors) -- would give them away if using non-certified devices (using part 15.407 certified devices only). But what other reason do they have of changing the MAC address...
I found that channels above 165 are clear sailing (low to no noise). ISM has not been noticed -- and can not be used for telecomunication purposes, so not at tower sites. At only 1 site do I find a WISP dubiously in part 15.247. This is all around the LA and Orange County noise rich basin area.
I think we should update the chart to better show these 3 allocations. A darker color for part 15.407 which is mostly unusable in metro areas. Then a lighter color, for the part 15.247 and ISM, because there's a considerable difference in what to expect in terms of noise and usability.
As a community, we should not shy away from 5825 to 5875 because we think it's too noisy. Rather, the opposite, we should establish a beach head to set precedence before WISP operators are squarely looking to use--when U-NII-4 allocation becomes effective and moves wifi up to 5850 with u-nni-4.
ref attached image from: https://apps.fcc.gov/edocs_public/attachmatch/FCC-13-22A1.pdf
Joe AE6XE