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WirelessRudy
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VH, VV or HH polorization mimo antenna discussion.

Sun Mar 18, 2012 6:33 pm

Interline from Poland has introduced some mimo antenna's that are available in both HH, HV or VV configurations.
http://interline.pl/modules/content/ind ... tegory=7#7
Probably some other vendors too.

Has anybody have any experiences with either one of these? Most of us know by now the HV type of mimo antenna's, but I am wondering what would be the pro's and cons of HH or VV antenna's?


I can think of one pro for a mimo VV (or HH) antenna: If you have a one chain 'n' antenna (siso) than the signal could theoretically 3dB higher (or longer reach) since the AP actually uses two antenna's to communicate with same CPE?
Is this right? Please give me your insight...

A con would be that with an AP equipped VV-Pol (or HH) mimo antenna, your VH cpe will only work on one chain.....
So you have to carefully work out what network you are building...


If both ends would have either VV or HH, would this have better, or worse, results than a VH on both ends in a full 2x2mimo setup?

Theoretical input would be appreciated, but real experiences are even more interesting! :D
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Rudy R. Puister

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czolo
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Re: VH, VV or HH polorization mimo antenna discussion.

Sun Mar 18, 2012 9:25 pm

Interline from Poland has introduced some mimo antenna's that are available in both HH, HV or VV configurations.
http://interline.pl/modules/content/ind ... tegory=7#7
Probably some other vendors too.

Has anybody have any experiences with either one of these? Most of us know by now the HV type of mimo antenna's, but I am wondering what would be the pro's and cons of HH or VV antenna's?


I can think of one pro for a mimo VV (or HH) antenna: If you have a one chain 'n' antenna (siso) than the signal could theoretically 3dB higher (or longer reach) since the AP actually uses two antenna's to communicate with same CPE?
Is this right? Please give me your insight...

A con would be that with an AP equipped VV-Pol (or HH) mimo antenna, your VH cpe will only work on one chain.....
So you have to carefully work out what network you are building...


If both ends would have either VV or HH, would this have better, or worse, results than a VH on both ends in a full 2x2mimo setup?

Theoretical input would be appreciated, but real experiences are even more interesting! :D
I try to explain that.
MIMO technology don't use just different polarizations. For working MIMO needs different signals. Maybe it's look strange, but this is not tha same. Recive signal can be different just if you shift antennas inside the box (signal theory). For MIMO it's recomended that the shift space should be at least 0,5 wave length. Of course for beter results the space between antennas should be bigger. Using VH polarizations leads to the same - signals are different.
Why using the same polarization MIMO antennas? Your answer is correct - because SNR could be 3dB higher. But, to get it work, the separation between (polarizations/antenna connectors) should be better than >20dB (MIMO technology requirements)

I can say, that new LTE base station antenas are MIMO 8x8, but inside thera are only 2 polarizations.

Read this lecture: http://kom.aau.dk/antprop/phdc04/pky/AA_PhD_MIMO_3.pdf

If you looking for better VV or HH antennas ask here: http://www.cyberbajt.com/en/shop_offer/ ... _mimo.html
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WirelessRudy
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Re: VH, VV or HH polorization mimo antenna discussion.

Mon Mar 19, 2012 1:30 am

hmm, its a bit acedemical text, what is the plain english translation?
If you looking for better VV or HH antennas ask here: http://www.cyberbajt.com/en/shop_offer/ ... _mimo.html
Why should they be better?
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0ldman
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Re: VH, VV or HH polorization mimo antenna discussion.

Mon Mar 19, 2012 5:22 am

I've got a few VV setups going. Both mounted to the enclosure, one above and one below, 12dBi and 9dBi, works beautifully, only single chain clients. I haven't tried dual chain.

I have another AP with two vertical antennas that are horizontally separated, I think 42 inches apart. Worked great in testing on the ground, doesn't work as well on location.

I will keep it going as is until I upgrade for more capacity. All of my recent AP installs are running dual vertical polarity with the above/below setup.

My next AP is going to be a dual polarity test.
 
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Re: VH, VV or HH polorization mimo antenna discussion.

Mon Mar 19, 2012 12:53 pm

If you looking for better VV or HH antennas ask here: http://www.cyberbajt.com/en/shop_offer/ ... _mimo.html
Why should they be better?
Check signals isolation in specification.
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