Understanding 450M uplink SNR

Hello to fellow members

I have a question, how is uplink SNR calculated on a 450M, in the following example I have a SM with

-66 rssi and 19/20 SNR

-70 rssi and 29/29 SNR

-74 rssi and 14/14 SNR

Makes no RF sense if the noise is the same on the sector.  Is this an error or a special calc by the 450M per lobe?

Screen Shot 2018-06-09 at 7.36.00 AM.png

Uplink is from the customer to the tower so wouldn’t this just be the overall noise floor of each sub? It’s a 90 degree sector so the noise heard when listening to each sub should be different.

I think this has always been true?


Hi Gino,

You can turn on more debug to try and help understand the UL.

In Configuration->Radio, then under Advanced there is the button to enable 'Receive Quality Debug'.

This needs an 'engineer' account on the radio to then see extra information in Home->Session Status and Tools->Link Status.

(I've got my radio engineering keyed as well but I don't think you need that)

It may also be worth running a link test to individual SMs in another window and see if anything changes. Sometimes this forces the rate adapt algorithm to update on a link that has low background UL traffic.

In an upcoming release we hope to have EVM per SM measurements (both DL and UL) available which may be more enlightening.

best regards,


Wouldn't uplink beamform mean that depending on the source of the interferer in the field some SMs would see better SNR than others?

1 Like

Hi Seth,

I was taking the statement that 'the noise is the same on the sector' to mean the sector was fairly clean RF wise and noise should be consistent between SMs.

However you are completely correct that beamforming WILL pick up different noise values if they exist at each SM in the case of interference.

best regards,