PM450 SM too close to tower?


Is there a minimum distance that a SM would need to be? I have a SM that is under .500 for distance to the tower.

The SM is set to allow 40meg and burst to 200meg but the user can only ever get around 5-10meg with speedtesting different days and different times.The linktest gives 200meg. I did not have a dish setup at the users location and they were getting around 20meg-28meg. Since adding the dish it has become worse. I have tried moving the user to a different AP but it did not help.

I am open to any ideas.


What model SM... (450, 450d, 450b, or 450i) are you using, and what is it set to... routed? bridging? NAT? Have you plugged a laptop directly into the SM to make sure that you're linking up at 100mbps FDX or 1gbps FDX? What kind of speed tests is the customer doing and to what site? Ideally you should be doing a test via iperf from your laptop behind the SM to a test server located in your NOC... that way you can see what throughput you get across your network. Perhaps there's a ethernet negotiation issue... perhaps there's some sort of congestion or issues between the NOC and the AP that serves the client?

You're going to have to test each link in the chain carefully until you find the source of the congestion.

Hi Eric,

Model 450,NAT, yes I have directly connected to SM with laptop and it links up fine with100mpbs FDX fine.

The user is using Would the user being so close matter at all or is the distance more on the further away from the tower where it comes into play? I have changed the AP to a different one and that did not help.


Hi flashy99,

If the placement of the SM and distance to the tower was a factor you should expect to see that in 'linktest' results being degraded


The linktest will check the basic RF capability which could be compromised by being NLoS, too far, below downtilt etc. There are also options for enableing bridging and MIR which may also be worth a try for comparision.

As your linktest results show 200Mbps that would point to the problem being elsewhere, but out of interest what are the Rx levels for this SM (at AP and SM) and what modulation rates and SNR is it reporting for DL & UL.

But if the RF was good why did changing to a dish degrade the performance? If you can share the above stats and linktest results maybe we can deduce some more. Or you could open a ticket and support will be able to collect diagnostics to help sort this out.

best regards,