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Access network design for branch, remote, outdoor, and campus locations with HPE Aruba Networking access points and mobility controllers.
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inconvenients of having Antenas of AP distribuited

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  • 1.  inconvenients of having Antenas of AP distribuited

    Posted Oct 02, 2013 03:01 PM

    Let say i got an AP 134 in a small warehouse.  And i put in one row one Antenna and on another row another antena, and another row.

     

    I ask this becaues i got one client in which he has another quotes of this kind of deployment

    He is offering one AP and also putting one antena per row...

    I never seen this...

    Im offering one AP per row

     

    Is there any inconvenient putting the AP and the antennas that way the other company is doing it?

     

    Cheers

    Carlos



  • 2.  RE: inconvenients of having Antenas of AP distribuited

    Posted Oct 03, 2013 11:05 AM

    Anyone?

    Or you guys dont undrestand the question??? maybe i didnt explain it properly?

     

    Cheers

    Carlos



  • 3.  RE: inconvenients of having Antenas of AP distribuited
    Best Answer

    Posted Oct 03, 2013 06:23 PM

    The antennas don't work that way.

     

    There are multiple antennas per radio, for diversity.

     

    One of our warehouses was installed by folks who thought one AP had two antennas so it could cover twice as many aisles, and the coverage is terrible. We're still cleaning that installation up.

     

    I suppose you could place the 2.4 GHz antennas down one aisle, and the 5 GHz antennas down the next, but your client will be happier with one AP per aisle. (after the price-shock wears off)

     

    If the competetition gets to depoly a demonstration, suggest your client make the demo on aisles which are full of product, the one antenna per aisle works when the aisles are empty.



  • 4.  RE: inconvenients of having Antenas of AP distribuited
    Best Answer

    EMPLOYEE
    Posted Oct 03, 2013 10:03 PM

    Almost all APs I see nowadays have multiple radios sharing multiple antennas. Also most of the time beacons are only sent on one antenna chain.

     

    I would definitely say do not do the one antenna per row.  The multiple antennas are for diversity and for multiple streams of data. They must cover the same area. 



  • 5.  RE: inconvenients of having Antenas of AP distribuited

    EMPLOYEE
    Posted Oct 03, 2013 10:05 PM

    Do you have the make and model of the equipment the other quote is offering? 



  • 6.  RE: inconvenients of having Antenas of AP distribuited

    Posted Oct 03, 2013 10:27 PM

    No.  The client just told me that the other company is offering him a few APs and multiple antenas from those APs and putting those antenas in  the warehouse rows... thats it.

    From the begginng he told me that, i told him that, it was not a good idea, and from the design point of  view is not right.

    I told him that  he has to take in mind that the lost of dbs he will have from the long cable going from the AP to the antennas, and that the multiple antennas were for the MIMO  and it should not be used that way, like the other forum member said it should not be used to cover more area(  i should have tell him this way sounds  a way simple formthe way i say it :) )

     

    I told him my design will be a way more expansive but i cannot give him a bad design, i mean,  just to sell him something, i would just give him a good design that i know it will works otherwise i wont.   And as my own policy i dont promese anything to the client that i cannot do or it cannot be done right... and i cannot do the correct coverage with a few APs to that warehouse.

     

    I came here to look for more reasons as well of course i dont know everything :)

     

    What i did was putting a design in the visual RF and explained it my design and why i was using that quantity of APS, that you should take in mind that the warehouse is fulll all to the top of products... and well other things.

     

     

    Cheers

    Carlos



  • 7.  RE: inconvenients of having Antenas of AP distribuited

    Posted Oct 30, 2014 11:39 AM

    Sean,  will you expand on the concept of beacons transmitted on a single Antenna chain?  I have seen intallations with external antenna with different orientations and I believe this to be a mistake.  If beacons are sent on a single antenna per radio basis then the transmit coverage area will be different from the recieve coverage area due to the antenna oriention.  The argument presented for this type of antenna orientation is to provide a decorrelated signal where one does not exist and therefore avoiding signal fade.  As presented in the outdoor VRD, indoor environments provide sufficient multipath.

     

    your thoughts