Interference with other ISP's..

So we’ve had a Canopy 900MHz system running fine for over a year.

All the sudden another ISP put up 3 (and i think are working on 1 more) systems within a 5-12 mile radius of us.

All the sudden all of our AP’s are saturated. When you switch an AP to an SM and do a spectrum analysis, it shows every frequency completely red.


http://img165.imageshack.us/img165/3883 … eetps6.gif

The ISP is using 900MHz Canopy equipment with Backhauls. Each tower site has (6) 900MHz integrated SM’s and 2 backhauls (to relay bandwidth). Our AP’s are up around 185 feet, theirs are around 150 feet. One of their locations is within 6 miles of us.

I wasn’t noticing ANY interference or saturation on my access points prior to them being around. A spectrum analysis showed only around -65. My question is how in the world did them putting up a few clusters totally screw my whole noise floor. Especially when some of those frequencies aren’t even used by Canopy (?).

I lost one of my testing links that was a link around 12 miles away. We’re on 906, 915, and 924. All of their new clusters use the same frequencies. The testing link that I had was North of us on 906. They put a cluster up smack in the middle of my test path and I can’t even see my AP anymore. I went from having a 1900 RSSI to not even being able to see it.

My question is…what are our options?

This other ISP is a rival and isn’t very fond of us. So most likely they aren’t going to be very cooperative. They currently have 0 customers, so their attitude is kind of let us lose our customers until we give up and then they’ll start advertising their system.

It almost seems as if it’s a battle of who has the deepest pockets. So what are our options so that we can keep our networks apart, yet exist in the same area?

Our good Friend Jerry has posted a solution to this exact problem not to long ago. Search the forum and you should be able to find it.

Shouldn’t be hard to dig through all 1500 of his posts to find it =P.

I found some of his posts, but most of them involved a syncpipe, and there weren’t many details (unless I missed something, which is VERY possible).

If it’s an easy explanation, why not just tell me? =P

http://motorola.canopywireless.com/supp ... ght=#19227

Thanks.

Am I misunderstanding how CMM’s work?

What is the point behind CMM Master and Slave then if you could put 100 CMM’s and they would all sync?

No such animal as a Slave CMM. They are all Master.

The master clock is the GPS satellite system.

Each CMM grabs the GPS sync and puts sync pulse on the AP. From there, the AP frames will be in sync with all other AP’s in the same band assuming that the DL%, Control Slots, and Max Distance.

So the setting for Master/Slave is for GPS?

Why would you use it?

Any clue how our AP’s are so saturated even in bands that he doesn’t have selected?

We can’t even switch to another frequency because all of our clients drop due to saturation.

Basically the example you gave makes it sound like I could set up a cluster 100ft away from your cluster, and as long as we both have CMM’s and the same settings…both will work at 100% efficiency (range won’t be reduced, etc?) ?

Because what they’re doing is dropping our customers off randomly and completely killing longer shots.

The Master/Slave setting is not used.

You need to read the Canopy Operators Guide regarding channel width, non-overlapping channels, sync, and frames. Also read the sections on frequency planning and how to re-use your 3 non overlapping channels.

My example assumes that you have a willing participant who will make changes to ensure that both systems operate correctly. It does not sound like that is the case.


If it were me I would start setting up the other ISP for a take down tomorrow. Here is how I would do it:

1. Call and inform them that they are interfering with your network and that you would like to set up a time to co-ordinate frequency usage in the area. The assumption is that they will not co-operate. Document the call. Make no threats, be diplomatic.

2. Write a letter to the other ISP and send it certified return receipt requesting a meeting to co-ordinate frequencies. Wait 3 days. Assuming a non-response, send another. Wait 3 days.

3. Call again to confirm that they received the letters and if they intend to work with you to co-ordinate frequencies. Again, the assumption is they will not comply.

Set up complete.

Send all of your documentation to the local FCC office requesting assistance. Explain that you have tried to set up a meeting to co-ordinate frequency usage in your area with no success. Explain that you have been operating in the area for over 18 months with an established customer base.

The FCC should take notice and get involved. You will look like the good guys and with a little luck the FCC guy will be a real stickler for co-ordination and shut the other guys down until they can figure out a way to work around your system (which is what is supposed to happen anyway).


Of course if they originally tried to co-ordinate with you and you were the obstruction then you are really in a heap of crap.

Good luck.

If your noise floor was a -65 before they showed up I feel for you. Just make sure all your sites are within FCC specs before you call them or it might end up costing you.