They call it a "game changer", which I think it really will be. MT has to find a solution to this FAST, or MT-product operators will lose the battle for service in congested areas soon!

http://dl.ubnt.com/marketing/Tolly21312 ... rmance.pdf

http://blog.4gon.co.uk/4gon-interview-u ... he-future/
(read the section about multi-lan RF technology. All the rest is humbug or we can deal with it... )

Taken from their forum; (Robert. Its an open forum and I didn't find a disclaimer, so I'll presume its free to show it here....)

"Guys -- we will reveal more about multi-lane RF technology with time. It is a game changer. Here is the basic idea behind it:
For those of you who go as far back as the PRISM 2.5 chipset and 802.11b days, you might recall that those radios worked much better outdoors in noisy environments...one of the main reason is because the receiver had much better adjacent channel rejection characteristics. If you were operating on Channel 1 for example, the radio would largely tolerate strong co-located signals on Channels 6 and Channels 11.
Fast forward to todays' world of tighty integrated low-cost single chip CMOS zero-IF radios, one of the big weaknesses in these solutions is the poor selectivity and adjacent channel rejection performanc. If signals are relatively high, there is longer such a thing as non-overlapping channels. Even if an AP is on a clean Channel 1 for example, if there are reasonably strong interferers at Channel 6 or Channel 11, the receiver performance will start tanking.
You can't solve this by simply putting channel filters up front on the RF side. Why? Because the fractional Bandwidth of a 20MHz channel at 2.4gHz is too small and very hard to filter tightly unless you use a monster external cavity filter. And even then, the radio becomes locked to single channel operation. So what do you do?

Welcome to Multi-Lane RF Technology...
We put our own synthesizer in front that is tied to the Wifi radio and downconvert the carrier to a 374MHz intermediate frequency (the same IF the old PRISM 2.5 chipset used). By doing this, we have significantly increased the fractional bandwidth of the carrier to allow near brickwall filtering. After filtering, we upconvert the signal back in to the radio.

The results in the lab have been pretty exciting. With an added 30dB+ of adjacent channel rejection through this active filtering design, we are able to get 2-3x the performance in crowded environments. There is a lot more we are going to do with this technology in the coming year."


I hope MT will come up with something similar SOON. We should all start pressing them..... (sorry MT guys, but you do need a kick at times... )

RF filtering is most welcome in any noisy environment,

However this version from what I read could not be called "game changer"
I reads with caution but have to welcome any significant improvements,
".......multiple APs, you’ll see a significant improvement......."

Channel 1 for example, if there are reasonably strong interferers at Channel 6 or Channel 11, the receiver performance will start tanking.
You can't solve this by simply putting channel filters up front on the RF side. Why? Because the fractional Bandwidth of a 20MHz channel at 2.4gHz is too small and very hard to filter tightly unless you use a monster external cavity filter. And even then, the radio becomes locked to single channel operation. So what do you do?
When someone can make active RF filters with variable frequency for use before the first stage of amplification, then you can use the term "game changer"


I hope MT will come up with something similar SOON. We should all start pressing them..... (sorry MT guys, but you do need a kick at times... )
Yes totally agree, who remembers those that finished second or third in a race?

Personally I love bandpass filters but they are so expensive and hard to find, plus u need a lot of planing if you are using them, but this "tunable active filtering" technology wops my hope for future wireless.
In the past year or two MT offer nice line of products - yes but they did not come up with some "game changer" innovative product or technology (Like Airfiber, they did not invest in synchronization what so ever if it works or not) simple I get this feeling MT is just following the others.

Personally I love bandpass filters but they are so expensive and hard to find, plus u need a lot of planing if you are using them, but this multi-lan RF technology wops my hope for future wireless.
In the past year or two MT offer nice line of products - yes but they did not come up with some "game changer" innovative product or technology (Like Airfiber, they did not invest in synchronization what so ever if it works or not) simple I get this feeling MT is just following the others.

Yes and no. They just use Atheros and look what they can do with what they get. They do no wireless engineering. But you still do not get a ptmp 11ac solution from UBNT. You're able to replace your Mikrotik 11n boards with 11ac boards right now.
BTW: We do not use Airfiber as they are still not able to be compliant in 24GHz ETSI (as I know) and they are quite big.

When someone can make active RF filters with variable frequency for use before the first stage of amplification, then you can use the term "game changer"

Isn't that exactly what they do?

You're able to replace your Mikrotik 11n boards with 11ac boards right now.

That might be true. But what we need is a way to get out of interference issues. If ubnt has 'patented' (they say) a technology that will indeed help a lot where MT will not follow up soon, I think I have to start changing my beloved routerboard for ubnt's stuff . Its going to hurt but my business needs to survive....

So hopefully MT will be coming with a response lots faster than before. (Don't we all know the tdma debacle. They were 2 years behind in delivering a stable product.......)

You're able to replace your Mikrotik 11n boards with 11ac boards right now.

That might be true. But what we need is a way to get out of interference issues. If ubnt has 'patented' (they say) a technology that will indeed help a lot where MT will not follow up soon, I think I have to start changing my beloved routerboard for ubnt's stuff . Its going to hurt but my business needs to survive....

So hopefully MT will be coming with a response lots faster than before. (Don't we all know the tdma debacle. They were 2 years behind in delivering a stable product.......)

MT cant respond as UBNT do not have a PTMP Wisp Product with this feature on the market. You can only respond to s.th. that is there ). UBNT Products are WYSIWYG (What you see is what you get) and not WTPYWG (What they promised you will get).

If you want MT to answer they should answer to the working GPS, working ATPC of ePMP 1000. We started deploying them with the same 40MHz Channel Back2Back (ABAB) at sites where we ran out of spectrum.

When someone can make active RF filters with variable frequency for use before the first stage of amplification, then you can use the term "game changer"

Isn't that exactly what they do?

They mention the difficulty in doing filtering at the front end so frequency downconverted first and then use Active filtering,
there is a fundamental flaw is this technique , what happens with unwanted high signal levels going through the downconverter to IF stage before active filtering - it could and probably does overload first stage amplification circuit.

When someone can make active RF filters with variable frequency for use before the first stage of amplification, then you can use the term "game changer"

Isn't that exactly what they do?

They mention the difficulty in doing filtering at the front end so frequency downconverted first and then use Active filtering,
there is a fundamental flaw is this technique , what happens with unwanted high signal levels going through the downconverter to IF stage before active filtering - it could and probably does overload first stage amplification circuit.

Ok, I think I see what you mean; If a strong signal hits the downconverter (and that can be any frequency in the band) it might destroy the downconverter or IT stage BEFORE it actually gets filtered out? Ok, that can be a point. An adjacent strong signal AP could this way still hammer the unit.
But if the downconverter to IF circuit is robust enough to survive that (I don't know if that is the case) their way is indeed helpful to filter out frequencies outside the band you actually want to use. So I don't know. It still looks a nice feature to me?

Ok, I think I see what you mean; If a strong signal hits the downconverter (and that can be any frequency in the band) it might destroy the downconverter or IT stage BEFORE it actually gets filtered out? Ok, that can be a point. An adjacent strong signal AP could this way still hammer the unit.
But if the downconverter to IF circuit is robust enough to survive that (I don't know if that is the case) their way is indeed helpful to filter out frequencies outside the band you actually want to use. So I don't know. It still looks a nice feature to me?

It is a step in the right direction placing active filtering on the IF stage,

Another method which could be used at the first stage of amplification is to have a variable threshold where any signal a of higher magnitude above the threshold level is inverted so it is cancelled (180° phase cancellation!)

For example on a busy mast set AP signal threshold to -50dbm, any signal below -50 is inverted and cancelled out before going to IF stage any signal above -50 is not inverted and passes through to IF stage,

Not sure if this method is possible but as it stands high signal levels plays havoc on amplification stages as if you simply attenuate the strong signal it also reduces the low signal, some method has to used which will attenuates high signal levels which and does not effect low signals as well.

Another method which could be used at the first stage of amplification is to have a variable threshold where any signal a of higher magnitude above the threshold level is inverted so it is cancelled (180° phase cancellation!)

For example on a busy mast set AP signal threshold to -50dbm, any signal below -50 is inverted and cancelled out before going to IF stage any signal above -50 is not inverted and passes through to IF stage,

Not sure if this method is possible but as it stands high signal levels plays havoc on amplification stages as if you simply attenuate the strong signal it also reduces the low signal, some method has to used which will attenuates high signal levels which and does not effect low signals as well.

hmm well, I hope MT guys are reading and start thinking (if they not already are doing so) in solutions. Because definately interference issues are the big issue in the years to come.

Your suggestion might work. But imho only on the AP. In CPE units its more difficult since here signal levels are weaker and concurrent signals can have same or even stronger signal levels.
I know, the 'multi lane RF' of ubnt is only available for AP's yet but in their forum they actually already point to the fact that the system would benefit even more if CPE's do the same. With 'Multi Lane RF' in CPE's you solve also the clients side interferences.

It would be nice to see if their system really works. And hope MT find something similar....

Personally I love bandpass filters but they are so expensive and hard to find, plus u need a lot of planing if you are using them, but this multi-lan RF technology wops my hope for future wireless.
In the past year or two MT offer nice line of products - yes but they did not come up with some "game changer" innovative product or technology (Like Airfiber, they did not invest in synchronization what so ever if it works or not) simple I get this feeling MT is just following the others.

Yes and no. They just use Atheros and look what they can do with what they get. They do no wireless engineering. But you still do not get a ptmp 11ac solution from UBNT. You're able to replace your Mikrotik 11n boards with 11ac boards right now.
BTW: We do not use Airfiber as they are still not able to be compliant in 24GHz ETSI (as I know) and they are quite big.

Yes and no as u said, UBQ has working AC but not compatible with N (in time probably it will be solved), Mikrotik has "working" AC (compatible with N you can use N gear on AC AP) .But at the moment on the market UBQ has 2 models of Racket5 AC one is lite version and one Rocket special for P2P with airprism technology included - which by the way I m going to try it very soon.
Mikrotik SXT SA5 is a very good product (personally I love it) but it’s not a "p2p solution" or solution for everything - that was the right direction how should Mikrotik wi-fi gear evolve - after a year I don’t see any other product that can offer good isolation or gear that can solve our noise problem "designed to work in a most harsh condition"
And yes, 24Ghz Airfiber is almost useless for EU (The world doesn't go around EU, there are other demanding markets in the world), but there is also 5Ghz Airfiber usable for us in EU, soon as UBQ confirm they are preparing 17Ghz version, more or less I am talking about technology used in AirFiber.
It is simple for us, we can’t wait Mikrotik or UBQ to come out with something new no matter how much we love Mikrotik or UBQ. We just have to use what it is the best from this two worlds

.........................It is simple for us, we can’t wait Mikrotik or UBQ to come out with something new no matter how much we love Mikrotik or UBQ. We just have to use what it is the best from this two worlds

I agree we cannot wait, what amazes me there is no company who sets performance first as paramount for equipment instead its price first, second appearance, and third performance?

Mikrotik SXT SA5 is a very good product (personally I love it) but it’s not a "p2p solution" or solution for everything - that was the right direction how should Mikrotik wi-fi gear evolve - after a year I don’t see any other product that can offer good isolation or gear that can solve our noise problem "designed to work in a most harsh condition"

SXT SA5 ist good for the money but antenna and housing is to weak for a professional sector. It's better to use a good sector antenna and a 912ac board. It makes no sense thinking of multi lane and other things when the antennas are weak and bleeding in all directions. It's like buying a sophisticated hi-fi system and cheap small plastic loadspeakers.

And yes, 24Ghz Airfiber is almost useless for EU (The world doesn't go around EU, there are other demanding markets in the world), but there is also 5Ghz Airfiber usable for us in EU, soon as UBQ confirm they are preparing 17Ghz version, more or less I am talking about technology used in AirFiber.

It is not almost useless in EU. It is forbidden. You cant reduce the power far enough to be compliant. If your signal offends another user he calls the regulations and then your link is taken offline immediately and you get fined. This power limits makes sense as it helps keep things reliable for all. 24Ghz is very useful for short links using gear which is built to be compliant. We use SAF Integras which work great and is compliant as you can reduce power even enough to use large dishes. They use diplexers to work with one antenna. To separate up/down signal enough they work with frequency spacing, filters and send/receive at different polarisations.
Real high tech cost some money but works predictable and your business is legal and cant be shut down. And it stays there for a longer time.

It is simple for us, we can’t wait Mikrotik or UBQ to come out with something new no matter how much we love Mikrotik or UBQ. We just have to use what it is the best from this two worlds

You've to take the gear which works best in your situation.