hi!i’m italian :lol: now i write the project of my first canopy wan!
sm1 sm 2---------ap1–bhm--------bhs–ap2--------------sm3
the bhm generate sync at ap1 with rj11 cable, it’s all ok,
the problem is to sync bhs with the ap2,with the rj11 cable it’s possible??
help me!!
thank’s :shock:
Yes.
Pins 1, 2, 3, and 6
Set the AP to receive sync on Timing Port.
If you are installing the BHS on the same tower as the AP then you will want to make sure you are using different bands.
If you are using 5.7 GHz for the BH’s and 5.7 GHz for the AP’s then you will have interference with each other even if they are using the same sync pulse.
What frequency are these radios?
Does putting the BH on 50% stop the possiblility of interferance in this type of setup ?
The ratio only affects the up/down speed
Canopy Support is pointing out that if you are using 5.7 AP’s and BH’s care must be taken to select frequencies that will not cause interference.
For example, set the BH20 at 5840, and the AP at 5735.
Obviously as much seperation in spectrum and veritcal height is always good.
However my understanding was that the interference due to sync pulse is caused when at a given cluster, if half the kit is trying to talk and other trying to listen. The listener will experience the inteference.
On a 70% BH setup with an AP the following would occur:
Time Pules 1 2 3 4 5 6 7 8 9 10
AP T T T T T R R R R R
BH T T T T T T T R R R
with the net effect that at pulese 6 and 7 we are causing inteference. However if you move the BH to 50% then you get:
Time Pules 1 2 3 4 5 6 7 8 9 10
AP T T T T T R R R R R
BH T T T T T R R R R R
which should work fine (or does work fine in our case). Please note that in the above case the co-located BH or all BH at the cluster in the same band have to run as masters. If you put in a slave you get
Time Pules 1 2 3 4 5 6 7 8 9 10
AP T T T T T R R R R R
BH R R R R R T T T T T
We have commonly colocated within very close proximity of AP’s in the same band but when we apply the above we have been ok. When some of my junior engineers not fully understanding the concept have messed up, we did see SM start to drop of AP’s.
In the above scenario, you can NOT have 2 AP clusters connected together, as the other side would be a slave BH with AP’s, resulting in totally out of sync. What we have is a cluster of BH which are all slaves, due to our geography and terrain it works quite well for us.
When we do need to connect 2 AP clusters we use a different band. The above understanding of the T/R diagram was explained to me by tech support over a year ago, and it has served me extremely well. Although they never advised on colocating in the same band.
You are right that the listener is the one affected however at some point that listener turns into the talker and vice versa. So they both will experience problems while listening.
You can adjust up/down, max distance, and control slots to try and line up the Tx cycles for AP’s and BH MASTERS’s. The problem though is just as you pointed out, when you colocate AP’s and BH SLAVES. Obviously we recommend that you do not install AP’s and BH’s using the same band on the same tower hoever that is only in perfect scenarios.
If you must colocate AP’s & BH’s in the same band then dont put the BH Slaves on the tower with the AP’s. Next use the frame calculator to adjust the values as done when colocating Hardware and Software scheduler AP’s. If you need more information on this then please see the 7.2.9 release notes.
http://motorola.canopywireless.com/supp … hp?catid=1
never co-located H/W and S/W so never needed to use Frame Calculator, but the distance on the BH is greater then 15miles we have set in the AP’s.
Also although all our AP’s are in H/W scheduling the BH are in S/W so we should look to moving BH to H/W.
In either case I will do some Frame Calculations and see if we can tweak the links.
Thanks
Ghina,
sorry some of the above may have confused you… To answer your question is , Yes it is possible,
Do as Jerry says, below is a more details of what is going on.
Your BH at AP1 is a master, you are running a timing cable from the AP1 to BHM. Although these are in sync in terms of having the same timing source, you need to ensure that the uplink/downlink settings are the same on the BH and on the AP. Secondly as Jerry pointed out, use 5735 on the SM and 5840 on the BH. Thirdly try to have as much vertical seperation between the AP and the BH. Fourth you should look at the frame calculator.
On BHS you can run a timing cable to the AP. A BHM acts like an AP and BHS acts like a SM. On a slave you do NOT have the option to set timing, as the timing is controlled by the BHM. If you look at the posts above from myself and Canopy, you may understand why this is an extremely bad idea. However on the AP2 if you set to recieve timing from timing port it will take timing from the BHS which is taking it from the BHM which is taking it from the AP1 (i.e your pop is in sync).
See if the above helps, if you are still experiencing issues, then you will have 2 choice, first get a CMM or sync injector for both sides, or the best solution get a different band BH.
Hope this helps.
Canopy_Support wrote: If you are installing the BHS on the same tower as the AP then you will want to make sure you are using different bands.
Is 5240 and 5300 a different bands or not? How many distance between frequencys will be a different bands?
5.2 is a different band to 5.7.
I would say once you have a seperation of about 200MHz you are good to go, chances of self interferance are very low. this is purely my opinion, I do not know the industry standard.