Cell Carriers One Step Closer To "Sharing" Your 5 GHz Bandwidth

[sfx2000]

Regarding DFS - the LTE-U/LAA/MediaFire devices have the same restrictions as WiFi...

In some regulatory domains - there is a listen before talk restriction on LTE-Unlicensed - unfortunately - the US isn't in that group...

 

[System Error Message]

time to make a jammer on the same frequency that the companies use and give them hell. since 5Ghz is unlicensed a jammer is totally legal if it is only on 5Ghz and not on DFS.

A lot of ground based radar dont operate at low altitudes that means you will have better luck with DFS than what the cell companies will as they will be using towers and altitude.

5Ghz is already getting crowded now that ISPs are giving routers with wireless AC so the number of free channels is rapidly decreasing, plus cell carriers now using 5Ghz, 5Ghz is going to turn into a pain in the near future especially in cities.

Whats really funny is the FCC making all the wrong decisions. They should be worried more about tx power (something which cell companies are gonna max) rather than channels because the US allows all the 5Ghz channels.

 

[thiggins]

since 5Ghz is unlicensed a jammer is totally legal if it is only on 5Ghz and not on DFS

FCC Part 15 forbids intentional interference. Jammers are NOT legal.

 

[thiggins]

I wonder in the area of DFS, has there been any benchmarks measuring how much of an impact on throughput it has due to the frequent checks it has to do (especially if there is no dedicated radio to check for radar)?

Devices operating in DFS channels must CONTINUOUSLY monitor for radar. This function is done partly in the radio MAC/PHY with some host processing required.

 

[System Error Message]

Devices operating in DFS channels must CONTINUOUSLY monitor for radar. This function is done partly in the radio MAC/PHY with some host processing required.

i know but DFS is mainly to do with location, only a moving object with radar would trigger DFS on a router so DFS channels are actually something that many can use.

Jamming isnt legal on the long range, you do have the right to jam many frequencies on your own property and cellphone companies would be putting their stuff on peoples property such as office buildings which is owned by someone. With the state of things if you own the office and the cell tower hanging on your office is causing issues, very rarely will the court take your side so the other legal option is to jam the specific frequency it uses as long as the jammer's range is in your office but it'd interfere with the cell receiver too. cell towers are very expensive so very likely they will attach it to someone's building.

mobile phone jammers are used in various localised public places that are at the same time a private property such as concert halls and in some sensitive places.

The point is that its an unlicensed channel and they shouldnt be using it since phones are pretty much important and used in emergencies. The impact of cell carriers using 5Ghz in cities and dense areas could be devastating for the people in that area as it gives wifi router manufacturers a major problem to deal with as people would blame them rather than cell carriers for poor performance/connectivity.

 

[thiggins]

The unlicensed bands are open for all to use, by law.

Please cite a legal reference that says you can jam frequencies on private property in the U.S.

 

[RMerlin]

Considering the low penetration capability of 5 GHz radio waves when hitting strong obstacles, is it possible that the idea is to mostly cover the outdoor, and that a brick wall would attenuate their signal to a point where your wifi router won't have any problem dealing with it?

 

[thiggins]

Considering the low penetration capability of 5 GHz radio waves when hitting strong obstacles, is it possible that the idea is to mostly cover the outdoor, and that a brick wall would attenuate their signal to a point where your wifi router won't have any problem dealing with it?

Since the main purpose of LTE-U is cellular offload, I'd think the carriers want to do that anywhere they can.

 

[sfx2000]

time to make a jammer on the same frequency that the companies use and give them hell. since 5Ghz is unlicensed a jammer is totally legal if it is only on 5Ghz and not on DFS.

Jammers are illegal in the US - there have been outfits that have been taken to the woodshed and fined seriously for this kind of behavior.

 

[sfx2000]

Since the main purpose of LTE-U is cellular offload, I'd think the carriers want to do that anywhere they can.

I wouldn't mind so much - the ISM/UNII bands are unlicensed, and pretty much anyone can use them with the caveat of "do no harm".

It's more a policy and ethics issue here - the carriers claim one thing, but we have 100's of MHz in the Cell/AWS/PCS bands that is laying fallow and not being used for anything - so the carriers are looking at the economics - it's much cheaper to put a few low power femto cells in as opposed to siting a Pico/Micro/Macro cell (with the attendant RF planning resources).

WiFi does not have exclusive use of the UNII bands - in fact it's the secondary user in many channels (to whit DFS is but one example), but the carriers do have exclusive use of their channels in the licensed space...

I'd rather see LTE-U in the white space channels - the technology is there and proven - that, along with the 3.4GHz unlicensed band, which for the most part is not being utilized at the moment - these two approaches, IMHO, balance the need of both the operators and general public - and doesn't impact the overall contributions of public usage in the ISM/UNII bands where WiFi has been very successful.

 

[sfx2000]

Considering the low penetration capability of 5 GHz radio waves when hitting strong obstacles, is it possible that the idea is to mostly cover the outdoor, and that a brick wall would attenuate their signal to a point where your wifi router won't have any problem dealing with it?

The bigger challenge would be in the campus environment where there is a fair amount of 5GHz in use for WiFi - and here is likely an arena where the carrier might want to use LTE-U, as the mobile density in that environment is going to be fairly high - so then one runs into the mess of conflicts between the enterprise IT staff and the local Wireless operators.

How do we solve that conundrum?

 

[Razor512]

If they begin using the 5GHz on channels used by the 5GHz access points, would it be possible for routers to add a function to keep LTE-U out, e.g., grab a 160MHz wide chunk of the spectrum, then spit out random frames at 1 watt transmit power whenever no other AP or client is doing anything? Will that help make LTE-U choose a different channel? If this is done, it will not be jamming anything. It will instead be more of discouraging LTE-U from wanting to be around the noisy neighborhoods.

 

[thiggins]

If they begin using the 5GHz on channels used by the 5GHz access points, would it be possible for routers to add a function to keep LTE-U out, e.g., grab a 160MHz wide chunk of the spectrum, then spit out random frames at 1 watt transmit power whenever no other AP or client is doing anything? ....

Sure. And that won't interfere with you neighbors' use of the channels either, right. And hike up the power to 1M Watts too while you're at it.

Jeesh.

 

[Razor512]

I was thinking more of since it looks for a channels that are less likely to bother WiFi clients, though it does not seem like it will treat WiFi clients and APs as it would treat radar on a DFS channel, thus what if we simply have it avoid the frequency range of the channels we are using right from the start. Basically having a noisy neighbor that is only quiet when other WiFi traffic is going by.
If done right, WiFi traffic may not be negatively impacted, while LTE-U will and similar technologies will always see a specific set of channels as a nonstop really loud WiFi party going on 24/7, thus looking for a different channel.

 

[System Error Message]

technically the use of wifi on the same frequency interferes with another wifi on the same frequency which is what jamming does as long as the signal is stronger. So this can be seen as cell carriers jamming 5Ghz for us and vice versa. Its a matter of how many watts the signal is and what makes jamming illegal is when the power limit is higher than lawfully allowed. So while the law doesnt allow jamming, its a grey area when it comes to functionality and tx power. hence why its really difficult to make it illegal to use a jammer within your own property as long as the signal doesnt bleed out, you could be using it for communications but it could be jamming something else thats working in the same area.

While 5Ghz is an unlicensed band anyone can use one of the reasons for operators to stay out of that band is mainly to reduce interference. Imagine if you run your own private radar installation(perhaps for science for detecting objects) and cell carriers start deploying towers that use the same frequency and start messing with your radar. No license is required for using that frequency but you wont be able to do your work anymore. This is essentially the same thing thats going on here. I know theres DFS but im just giving an example that doesnt involve something critical that requires DFS. You could probably go to court but you are likely to be overuled as ISPs have their hands everywhere and people care more about their reception than they do about your work.

consumer wifi is restricted by tx power, the cell carriers would obviously have higher tx power but they arent going to see most of the other 5Ghz around. In cities its going to get to a point like with 2.4Ghz wifi, just too many devices around resulting in poor performance for everyone and no free channel to choose from. This isnt just bad for the consumer, its bad for the carrier as well to use a band subject to more interference and changes.

 

[thiggins]

Jamming and contending for bandwidth are not the same thing.

Multiple Wi-Fi networks using the same channel are not "jamming". As long as they are in range of each other, the Wi-Fi CSMA/CA listen-before-talk protocols will work as intended.

If devices intentionally did not listen before transmitting, that would be jamming. Properly operating Wi-Fi networks do not do this.

 

[sfx2000]

I wonder if we're stuck talking in circles here...

 

[thiggins]

I wonder if we're stuck talking in circles here...

In circles about what?

 

[sfx2000]

In circles about what?

the whole jamming sub-thread within this topic