CBRS: frequency and/or channel bandwidth change on PMP 450 series

Summary: This article will guide you through the steps to change the frequency and/or channel bandwidth in CBRS devices.

Product: PMP 450 series radios using CBRS (3.6GHz)


After checking the tower scan from the spectrum analyzer as mentioned in the community post PMP 450: Run a tower scan (Spectrum Analysis) check the channel ranking here and choose a clean channel.

To change the carrier frequency and/or channel bandwidth there are two methods that can be followed:

Note: Frequency and bandwidth change grant authorizations are subject to spectrum availability on the same day. It can take up to 24 hours if CPAS is required before a grant can be issued.

Method 1: Make the changes locally on the AP GUI under configuration>>radio.

When the changes are made, the grant will be relinquished and it will take 2 minutes to receive a response from the SAS for the request.

Method 2: This can be used if the changes must be done to the management tool under CBRS>>Management tool.

(Note: Method 2 should ONLY be used if CBRS is Disabled on the AP)

  1. Go to the cnMaestro CBRS Management Tool.

  2. Click on the Device name of the AP on which the frequency and/or channel bandwidth need to be changed.

  3. Select the AP and SMs registered under it as shown below then click on Deregister and selected:

  4. The above operation will give you a confirmation pop-up where we need to click on ‘Yes’:

  5. Wait for a few seconds, the Grant Status should change to Deregistered on all the selected devices:

  6. Once they are deregistered, click on the Re-initiate button, and then choose selected:

  7. You will see a pop-up to either continue with the current carrier frequency and channel bandwidth or if you would like to run the Spectrum Inquiry.

  8. Click on the Spectrum Inquiry button and you should see the Spectrum inquiry results below:

  9. Choose the Carrier frequency and Channel BW then click on Calculate Max EIRP.

  10. After clicking on the Calculate Max EIRP button, you should be able to see the Max EIRP for each CBSD as shown in the list below:

  11. To continue with the Max EIRP allowed by the SAS, click on the Save button, or else select a different carrier frequency.

Note: If the channel bandwidth that is currently configured on the AP and the one that we are changing it to are different, then the AP will perform a reboot and all the SMs will be disconnected temporarily.

Syncing CBRS parameters to the device:
If the device is in the Authorized state, the user can manually select the SYNC button to enable CBRS in the device by sending the configured parameters in the CBRS Management Tool.

Hello @imu100!

Is there a way to do the Sync action via API or on the device via SNMP or something? We’re trying to do some re-syncing automations and are looking for possible ways to go about it without having to manually go through the cnMaestro GUI. Any advice would help.