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Aifiber little spectrum left.

We just had an incedent where a Rocket ptp link with Rf Armour that was on our mast endend up on the same channel as our AirFiber's 5Ghz.This totally killed the capacity of the AF and made me relaise that if some other ISP slapped up a unit nearby we would have major problems as the spectrum is croweded.Correct me if I am wrong If the AF had airprisim this would help.  

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Re: Aifiber little spectrum left.

[ Edited ]

Hi scc,

AirPrism is an attempt to improve the adjacent channel performance of the radios that use off the shelf WiFi chipsets.  AF5 uses a completely different radio architecture that uses a combination of discrete components and a high performance re-configurable Zero IF (ZIF) receiver.  The ZIF receiver as used in the AF5 already incorporates substantially more selectivity than airPrism so there would be nothing to gain.

 

As has been pointed out, on-channel interference can't be improved by airPrism or any other filter for that matter.  We do have some on-channel interference mitigation strategies that have been implemented on AF that do enhance its robustness however.

 

(EDIT: Didn't see Claude's post so sorry for beating a dead horse!)

 

Gary

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Re: Aifiber little spectrum left.

As I believe it airPrisim reduces adjacent channel interference not same channel interference.
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Re: Aifiber little spectrum left.

The AirFiber already has filtering that is better then even AirPrism.

 

As mentioned by Magbis, the excellent filters of the AF line and AirPrism on the AC line filter adjacent channel noise that naturally bleeds past the frequency edges. 

 

Though if someone puts something on the same frequency as an AF, in my experience they will generally suffer more than the AF will.   It depends on aim and how the two mutually see if other, but generally other devices will slighly lower an AF links throughput, while the AF will pretty much kill other devices because of its constant stream. 

 

 

 

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Re: Aifiber little spectrum left.

[ Edited ]

Hi scc,

AirPrism is an attempt to improve the adjacent channel performance of the radios that use off the shelf WiFi chipsets.  AF5 uses a completely different radio architecture that uses a combination of discrete components and a high performance re-configurable Zero IF (ZIF) receiver.  The ZIF receiver as used in the AF5 already incorporates substantially more selectivity than airPrism so there would be nothing to gain.

 

As has been pointed out, on-channel interference can't be improved by airPrism or any other filter for that matter.  We do have some on-channel interference mitigation strategies that have been implemented on AF that do enhance its robustness however.

 

(EDIT: Didn't see Claude's post so sorry for beating a dead horse!)

 

Gary

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Re: Aifiber little spectrum left.

Thanks for the reply .. the Rocket that killed the AF capacity was facing approximately 90 degrees to the AF and is about 2 meters below the Air fiber just shows even with the RF armour you still get some interference. 

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Re: Aifiber little spectrum left.

Hi scc,

Yes, you will get some interference if you use the same channel or a channel that shares part of the frequency used by both radios. I suggestion is to always try to separate frequencies as much as possible, and if you're using closer (or near same) frequency in that tower, try to separate the radios as much as possible, 20ft or more if possible.

 

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Re: Aifiber little spectrum left.


@scc wrote:

We just had an incedent where a Rocket ptp link with Rf Armour that was on our mast endend up on the same channel as our AirFiber's 5Ghz.This totally killed the capacity of the AF and made me relaise that if some other ISP slapped up a unit nearby we would have major problems as the spectrum is croweded.Correct me if I am wrong If the AF had airprisim this would help.  


What is the distance this AirFiber5 link is running at. It may be time, if possible, to go with an AirFiber24(HD). Or even a licensed link if your to far for that to work well. 

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Re: Aifiber little spectrum left.


@ClaudeSS wrote:

The AirFiber already has filtering that is better then even AirPrism.

 

As mentioned by Magbis, the excellent filters of the AF line and AirPrism on the AC line filter adjacent channel noise that naturally bleeds past the frequency edges. 

 

Though if someone puts something on the same frequency as an AF, in my experience they will generally suffer more than the AF will.   It depends on aim and how the two mutually see if other, but generally other devices will slighly lower an AF links throughput, while the AF will pretty much kill other devices because of its constant stream. 

 

 

 


Claude is dead-on here (as usual).



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Re: Aifiber little spectrum left.

HI Mr Hone the link is 40KM and in europe the rain would kill the AF 24 Man Embarassed

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Re: Aifiber little spectrum left.

We do not have any links at this distance yet. Probably doing one this summer, as we expand into another city.