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Jafster
join:2013-02-07
111111

Jafster to lutful

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to lutful

Re: How can i use single Freq. in 4 Canopy AP's in one tower?

Thanks Lutful... The green colors are facing to each other you think it will work that way? i am assuming that the green color are on the same polarity and same freq.
wirelessdog
join:2008-07-15
Queen Anne, MD

wirelessdog

Member

How far are the physical towers from each other? Are you using the factor AP's with no modifications or are you using external antennas on your AP's?
Expand your moderator at work
lutful
... of ideas
Premium Member
join:2005-06-16
Ottawa, ON

lutful to Jafster

Premium Member

to Jafster

Re: How can i use single Freq. in 4 Canopy AP's in one tower?

said by Jafster:

Thanks Lutful... The green colors are facing to each other you think it will work that way? i am assuming that the green color are on the same polarity and same freq.

Yes, same color means same channel and polarity. SM antennas are usually more directional and there is no problem even if beams of same frequency and polarity cross each other while going to different APs.

The only problem that can happen in TDMA systems is a very strong SM in one sector swamping a very weak SM beam in the directly opposite sector. Think about the short fat red arrow SM directly opposite one of the long thin red arrows on tower 2.

I drew some arrows to show how you could assign same SM to different APs in the various frequency zones. The general goal of frequency allocation and sector antenna orientation is to maximize SM-to-AP pairing options. You will notice that the green frequency zone is actually the largest and most flexible.
Jafster
join:2013-02-07
111111

Jafster to wirelessdog

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to wirelessdog
Wirelessdog... the distance of my tower is not morethan 2 miles to each other.
with regards to my AP, i didnt do any modifications with the antenna.
Jafster

Jafster to lutful

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to lutful
Thanks lutful for your effort. i really appreciate. i will do a test with this setup.

"The only problem that can happen in TDMA systems is a very strong SM in one sector swamping a very weak SM beam in the directly opposite sector. Think about the short fat red arrow SM directly opposite one of the long thin red arrows on tower 2."

Do you know a way or additional configurations that can prevent or the above problem?
lutful
... of ideas
Premium Member
join:2005-06-16
Ottawa, ON

lutful

Premium Member

said by Jafster:

Do you know a way or additional configurations that can prevent or the above problem?

You can use ATPC feature available in Canopy/Alvarion to keep SMs below a maximum SNR value which allows the weakest SM on the opposite sector to operate with reasonable SNR.

You can also manually reduce TX power output for strong signal SMs ... which are usually at close range and aim towards the center of the AP's sector antenna beam pattern.

P.S. The best technical solution requires implementing system-wide scheduling so that SMs transmitting in the same time slot provide similar rssi values at their APs by adjusting their transmit power per slot.