SMs are Re-registering...

Can somebody please help me figure out why my SM’s are dropping/re-registering?

I currently have a cluster of three AP’s providing signal to about 10-15 SM’s per AP. I am using Canopy 2.4Ghz with 7.2.9 software. I am also using Software Scheduling and I have Transmit Frame Spreading enabled. There is great line of sight and strong signal strength.

I do not, however, have a CMM for this cluster as I was told that it is only needed for a cluster of more than three AP’s.

Any insight would be greatly appreciated…

Two things I would recommend:

1 - Turn Transmit Frame Spreading off. In theory you only need this if you are having issues with SMs dropping off or re-registering due to another Cnaopy cluster interfering (no sync).

2 - Either install a CMM or use one of your APs as a timing master (wth a Y-cable) for the other two. Depending on how closely they are mounted to each other you may still be experiencing desense between the APs. ie. you can have a VHF radio and a UHF radio that are 300 MHz apart in the spectrum but they can still cause desense and interference with each other. It can be worse when the radios are only 20 MHz apart in the spectrum.

Also, what are your signal and jitter levels for the problem SMs? Does this affect all 3 APs? Does it affect all SMs on an AP?


Aaron

Not sure what you mean about this Y Cable?..

So, we have 3 AP’s.

#1) Color 1 / FREQ: 2415
#2) Color 2 / FREQ: 2430
#3) Color 3 / FREQ: 2445

On all 3, we are noticing that the subscribers are dropping and Re-Reging.

Jitter is always sub 4 and RSSI is always above 800 to 900 on all of them.
Even when it drops.

We have enabled Time Frame on all the AP’s.

The Distance between AP’s is less than 5 inches appart. They are on a Cluster Mount.

We don’t want to spend the $1300 on the CMM, so is there something else. How do we build this Y Cable, and how does it work. Right now, they are all on GENERATE SYNC.

Paul@MDSWireless wrote:

We don't want to spend the $1300 on the CMM, so is there something else. How do we build this Y Cable, and how does it work. Right now, they are all on GENERATE SYNC.



Paul, check out this GPS alternative, I think it was like $500

http://motorola.canopywireless.com/support/community/viewtopic.php?t=1511

Excellent…

i will try…

Also, how about this Y-Cable solution?..

SO, would it be possible to set 1 of the AP’s to GENERATE a SYNC,
and the other 2 AP’s to Sync to Received Signal (Timing Port) ???

Would this work?

And we make some sort of a Y-Splitter cable that connects all the AP’s together through the Timing port.?

#1) Color 1 / FREQ: 2415
#2) Color 2 / FREQ: 2430
#3) Color 3 / FREQ: 2445


Bad idea. These radios have a channel width of 20 MHz - that means they should be configured at least 20 MHz apart (10 MHz on each side of the channel) to eliminate adjacent channel interference. Motorola states that the three non-overlapping channels in the 2.4 GHz range are 2415, 2435, and 2457.5 (25 MHz apart on this one). You only have 15 MHz between your channels - that means you have 5 MHz overlapping. This WILL cause problems.


The Y-cable is simply taking the timing from one AP and sending in the timing portd of the other two APs - just like you said...
SO, would it be possible to set 1 of the AP's to GENERATE a SYNC,
and the other 2 AP's to Sync to Received Signal (Timing Port)

I'd have to look up the pinout for the timing port in the manual but it will be the easiest solution for timing for you right now.


Aaron

the same thing happend to us sometime ago.
We had to separate the SM´s from one another 9FT vertically and put a wall behind them.
The reason for this is that the Sync pulse from each AP1 is interfeering with the rest.

Let me know if there is anything else that I can help you with.

Adolfo