we have deployed PMP450i and once the SM integrated into the AP with a 2km link distance, it looks to operate in low modulation,
RSL -49.5 dBm (-52.0 dBm V/ -53.0 dBm H)
Registered 8X/2X MIMO-A.
Expected to operate in 8X/6X MIMO-B.
Does anybody have an idea this behavior is normal or due to any complication in the unit or configuration?
Also, have details of the threshold for each modulation level in PMP450i (16.2.3)?
If your screen cap is correct your uplink power level is -97 which would explain your low modulation level and I’m surprised you can maintain a stable link at all. Check your power and antenna gain setting on the SM.under configuration - radio. Is this an integrated radio? If its connectorized you could have a bad antenna/cables.
On the AP, disable “Adjacent Channel Support”, and set the “SM Receive target level” to -60dBm.
ALSO, if you’re using 450i you should upgrade your firmware to release 20. A major notable benefit to this is intermediate modulation modes or “IMM”… which adds 3/5/7 modulation steps.
It looks as though someone is running a 20MHz channel centered on 3650 very close or on the same tower as you.
If you’re running back to back frequency reuse and this noise is being created by you, then you will need to make sure that all relevant settings are matched and/or you’re using Cambium’s sync calculator to make sure that your sync settings are correct. You will need to follow Cambium’s recommendation on antenna specifications and placement in order for back to back reuse to work optimally.
If you are not the one creating this noise, then the energy levels are too high and you will need to find a different channel. Unfortunately, ATM, SAS’s aren’t aware of other operators operating on assigned frequencies, so you will still need to do some work to find a clean channel and/or coordinate with your competitor. Worse case scenario is someone operating pirate-style and not using a SAS.