LTE-U small cells will be certified under Part 15 rules.
And in other places you tell us that LTE-U is a combination of a licensed channel with an unlicensed one. How can it be Part 15 if it is using cellular licensed channels that are covered by Part 22? The story keeps changing.
In the same way that a cellular phone is certified as being a Part 15 device (for Wi-Fi and Bluetooth) and certified as a cellular device for 2G/3G/4G. Multi-radio devices are very commonplace with smartphones being the most common. So an LTE-U small cell would get certified under the rules for cellular and the unlicensed radio transmissions would be certified under Part 15.
That Qualcomm -- YOU -- are creating a system that is deliberately incompatible with the existing WiFi users so that WiFi users are impacted to give your cell customers that wonderful "UX". That Qualcomm -- YOU -- make equipment that cell companies can install that use the private licensed frequencies for data, and now you want to jump into the unlicensed ones and act in a way that will degrade every other user's communications. I've already said that.
Not sure how you make the jump from Qualcomm wanting to enable the use of unlicensed spectrum by cellular operators, to Qualcomm wanting to "degrade every other user's communications". Degrade communications for customers of our own Wi-Fi products? Degrade communications to Wi-Fi access points that are built on Atheros chips? How would that benefit Qualcomm or the mobile operators? Forgetting the backlash and the bad PR that would result as a consequence of that (and incurring the wrath of the FCC), how would it make business sense for Qualcomm to harm its own products in the field?
Then you should have said that from the beginning, instead of give technobabble nonsense about how it is impossible for LTE-U to interfere with any existing WiFi and how Qualcomm doesn't have to care because the bands are so large.
I did say that. In my first response to your comment that mentioned "the fine article", I said the article is wrong and has done great harm by misinforming its readers. I wouldn't characterize my answers as "technobabble nonsense" - I was simply trying to provide you the technical facts. This is a technical discussion, and a simple exposition of the facts should make it quite obvious that there is no grand conspiracy here, and that both the design of the system and the empirical evidence show that LTE-U has no more of an impact on 5GHz Wi-Fi (to be very, very specific) than adding another Wi-Fi access point.
Existing WiFi services don't deliberately interfere with each other by using a different protocol that doesn't LBT or uses a shorter transmit gap.
Perhaps a basic understanding of radio communications could help in this discussion. Any kind of over the air transmission by one radiator robs other transmitters from capacity. Either by increasing the noise floor (thus reducing the SNR and reducing bitrate as dictated by Shannon theorem), or by reducing the amount of time that the other transmitters can use for their own transmission, in the case of LBT. So the Boingo access point in this example, if it is on the same channel as your personal hotspot, would have the effect of reducing the amount of time your hotspot can transmit over the air (because your hotspot, using LBT, has to back off and wait). Thus it reduces your throughput. Thus it is having an impact on your experience. QED.
if Qualcomm uses a protocol that doesn't follow the same fairness rules that everyone else does in a license-free public frequency band.
Apologies, but once again you are misinformed. Wi-Fi uses LBT, but LBT is not used by "everyone else" as you imply. Here's a list of radios that work in the unlicensed bands that do not use LBT:
It won't. LTE-U shares the spectrum fairly with Wi-Fi. No more of an impact than adding a Wi-Fi access point.
You can see test results for yourself. Here are test results from a 3rd party (Signals Research Group) who tested LTE-U impact on Wi-Fi.
LTE-U is a proprietary system developed by the LTE-U group for use in North America.
LTE-U is built on the global 3GPP Release 10 specification for LTE. It is backed by the leading providers of LTE technology. How many backers does a technology need to go from "proprietary" to "standard"? 10? 100? 1000?
It takes advantage of the fact that the 5Ghz band is not regulated in the US.
False. The 5GHz band is regulated by FCC Part 15 rules, specifically subpart E (regulations for the Unlicensed National Information Infrastructure devices). Here's a link to the US regulations which govern LTE-U.
LTE-U does not implement the "Listen before talk" mechanism used in WiFi to allow stations to co-exists on the same frequency.
Neither does Bluetooth and Bluetooth Low Energy, 8021.15.4 (used for ZigBee and countless other proprietary protocols), cordless phones, AMIMON's 5GHz Wireless HDI "standard" (it's backed by only 13 companies - does that qualify it as a standard?), Nordic semiconductor's proprietary 2.4GHz transceivers, TI's proprietary 2.4GHz transceivers, Digi's proprietary 900MHz and 2.4GHz transceivers, every 2.4GHz radio used for RC cars/helicopters/drones, and countless others. Should I keep listing them?
Tests by companies like Intel show that CSAT can greatly impact packet latency in WiFi which impacts things like VoIP and streaming video
Please provide a link to the test results.
The former are given over to the belief that the unlicensed spectrum in the 2.4 and 5GHz band were set aside for their use while the latter having fat wallets can "buy their own damn spectrum"
I understand that this is the perception, but law, regulations, and precedent clearly show that this is not the case. I've given plenty of examples of companies other than cellular operators deploying for-profit networks in unlicensed spectrum - using Wi-Fi or otherwise.
It's also hard to not be skeptical that this would only be deployed at convention centers, malls, and the like and that it would be kept to the power levels allowed to unlicensed operators.
But there's a simple verification regime in place for this. It's called FCC certification. LTE-U equipment has to pass Part 15 rules in order to be certified. If they don't pass certification, they can't be bought/sold/deployed. Any equipment found violating these rules under which they are certified would incur the wrath of the FCC.
If it is to have any range at all and be useful in any way, it will have to use more power than Part 15 allows. Otherwise it will just be yet another short-range WiFi service, which we already have. Why should it replace WiFi? If it isn't supposed to replace it, then don't put it in the same frequencies.
Any intentional RF radiator sold in the United States has to pass through FCC certification before it can be sold/bought/deployed. LTE-U small cells will be certified under Part 15 rules. That means an FCC-certified lab will test them for compliance with all aspects of Part 15 rules for the UNII bands, including power output. If they use more power than Part 15 allows, then they would not pass certification and cannot be sold/bought/deployed. But of course that won't be the case - because they are in fact designed to comply with Part 15 limitations on power output, so that they can pass FCC certification.
The goal is to improve the "UX", but only for cell users.
And a Wi-Fi ISP like Boingo that blankets an airport with Wi-Fi access point is only trying to improve the UX for their own customers and not anyone else. So what's your point?
From TFA:
The catch, of course, is that LTE-U's frequencies are already being used by every Wi-Fi access point in America,
And my access points are all 2.4GHz. I've found the 5GHz points to be few and far between. So much so that most of my devices don't have that built in. The statement can only mean it will use both 2.4G and 5G frequencies. Or should we ignore the obvious meaning of "every" and use instead the Qualcomm UX managed-experience definition?
I'm almost at a loss for words here. The article is wrong. This is not an "opinion", it's a question of facts. Verifiable facts. Here is the specification for the bands of operation for LTE-U straight out of the LTE-U spec document (available here for your perusing):
the LTE-U operation will be limited only to the following carrier frequencies for U-NII-1 and U-NII-3, respectively. U-NII-1 o {f-0.2, f-0.1, f, f+0.1, f+0.2 | f = 5160, 5180, 5200, 5220, 5240} MHz U-NII-3 o {f-0.2, f-0.1, f, f+0.1, f+0.2 | f = 5745, 5765, 5785, 5805, 5825} MHz
Is a direct quote from the actual LTE-U specification enough to correct the patently false information from the article? If this is not enough, then I don't know what would be.
This was not the case the CableLabs study which did indeed use a commercial implementation. Further, listen before talk in LTE-U is only now being a proposed as part of the standard. There are vendor specific implementations that already have this, but the standard does not and did not when the tests were done.
Are you referring to Slide 9 of the CableLabs presentation? What the chart there fails to show is Wi-Fi throughput in the presence of other Wi-Fi. That's the baseline. No one is saying that LTE-U will have zero impact on Wi-Fi throughput. But Wi-Fi impact on Wi-Fi is also not zero. What needs to be compared is LTE-U impact on Wi-Fi throughput versus Wi-Fi impact on Wi-Fi throughput. And the CableLabs presentation doesn't show that - so the data set is incomplete.
I'm glad you say you "realize this is completely legal by current regulations". Because it is.
I don't think mobile operators are asking for an exception to the rule. They're asking to abide by the same rules that already allow cable companies, hotels, airports, wireless ISPs etc. to benefit from this shared resource. That's all there is to it.
Doubt is a pain too lonely to know that faith is his twin brother. - Kahlil Gibran
