Many network operators have important questions about implementing CBRS solutions. This general information is provided to assist network operators in developing deployment plans and leveraging their PMP 450m wireless broadband networks.

To participate in the Cambium Networks beta test, check out the latest open beta announcement.

Join the CBRS discussion on the Cambium Networks Community.

General timeline on CBRS major milestones (subject to change):

January 2020

  • Cambium Networks CBRS open beta begins (cnMaestro cloud)
  • 3.5GHz spectrum open for beta (3550 – 3650MHz)
  • It’s possible that all 150MHz would be available, subject to part 90 and incumbent status in the region

February 2020

  • Billing begins for registered devices in the SAS
  • cnMaestro on-premises support for CBRS
  • GA availability of cnMaestro CBRS software and PMP450 firmware (subject to change)
  • PMP450b High Gain SM shipping

March 2020

  • 1st Payment for CBRS SAS devices (30 days arears)

April 2020

  • Expiration of existing part 90 licenses, unless an extension was granted
  • Existing part 90 devices are supposed to turn off or migrate to CBRS
  • CBRS devices able to use 3550– 3700MHz, subject to part 90 and incumbent status in the region

Summer 2020

  • PAL’s expected to go up for auction
  • FCC Auction 105
  • 10MHz per PAL, up to 4 PAL’s per entity, 7 PAL’s total (70MHz of spectrum)
  • PAL’s are not an assignment of spectrum (e.g. 3550-3560MHz), rather priority access to the spectrum during grant request
  • $0.02/MHz/pop per county minimum bid (e.g. if the county has a population of 1,000,000 the minimum bid is $200,000 for a single, 10MHz PAL)
  • If purchasing multiple PAL’s, the spectrum would be contiguous (i.e. two PAL’s would be a 20MHz wide channel)
  • PAL’s are leased for 10 years, with option to renew once (no anticipated fee for renewal).
  • If some/all of the PAL’s are not purchased, it will open to GAA spectrum
  • It is expected that another round of auctions will occur in the future, for counties that did not auction all 7 PAL’s
  • Assuming all 7 PAL’s are purchased, the 150MHz will be divided:
  • 70MHz of PAL
  • 80MHz of GAA
  • Both subject to exclusion zones and incumbent status

In order to participate in CBRS (beta or production), the following requirements need to be met:

Use of a certified CBSD (CBRS Device).  All PMP450 platforms are part 96 (CBRS) certified as CBSD Category B.

  • PMP450 (beta) firmware v16.2 or greater

Registered cnMaestro cloud account at

  • This is required for either cnMaestro cloud or cnMaestro on-premises deployments
  • Provides initial SAS account creation and payment portal (not available in beta)

At least one CPI (Certified Professional Installer) on staff

CBRS AP’s management traffic must be routable to the cloud (Domain Proxy)

  • May require network changes to accomplish
  • cnMaestro cloud users should not need any change (possibly additional firewall settings)
  • cnMaestro on-premises users typically require change.  The most common architecture is to add a NIC interface to the cnMaestro server and use cnMaestro as an HTTP proxy (not available for beta).  See E-Learning for details.

Important considerations/decisions prior to setting up CBRS:

Decide on a SAS provider

  • Cost (billed through Cambium) and CBRS operation are the same across all SAS providers, but some offer additional services
  • Google or Federated at this point, with CommScope in the future*
  • If you have an existing SAS Org/User ID (i.e. for another manufacturer), you will still create one for Cambium devices

Acquire CPI certification(s)

  • CPI certificate is needed every time a device is registered in the SAS
  • Keep your CPI certificate password (SMS-ed or emailed with certificate), it is needed every time a device is registered in the SAS

Decide on cnMaestro instance and network architecture

  • AP’s will communicate directly with the Domain Proxy (SAS) in the cloud, but require cnMaestro for Domain Proxy information and credentials.
  • AP’s will have a heartbeat to the Domain Proxy (SAS), which needs to be maintained for the device to transmit, using same QoS as cnMaestro management messages
  • AP’s will proxy SM heartbeat, as well as, all CBRS messaging to the Domain Proxy (SAS)

Decide on CBSD type(s)

  • CBRS devices will be LTE or Cambium
  • To date, no other existing part 90 manufacturers have recertified for part 96 (Category B CBSD)
  • PMP450m (and PMP450m limited) are able to achieve the high (50dBm) of EIRP (channel size dependent)
  • Excellent performance, especially with beamforming and MU-MIMO
  • PMP450m limited is a non-MU-MIMO AP (license key restriction), but has high EIRP and beamforming
  • Legacy PMP450/450i AP’s will be hardware limited to 40dBm/42dBm (designed pre-CBRS)
  • Similar RF performance to existing part 90 operation

Verify/Setup location information for AP’s and SM’s (in cnMaestro)

  • Lat/Long/Height information is all needed for device registration
  • cnMaestro tower information needs to be correct, or may overwrite grant information, causing service disruption.
  • Do not adjust location or radio information after registering device with the SAS

Consider setting up a Syslog server for monitoring CBRS messaging on the device

  • CBRS status also SNMP pollable

Consider/determine internal process for the registration and de-registration of devices within the SAS (via cnMaestro)

  • Any device registered in the SAS for more than a specified number (TBD) of days of the month will receive a bill (even if not installed at customer)
  • CBRS devices can revert to part 90 operation until part 90 license expiration, assuming a license is held
  • Ensure proper SM scan list settings and AP radio configuration for part 90 prior to revert

In order to participate in the current open beta, the following steps need to be done:

Create a cloud cnMaestro account and Cambium ID

  • If this has already been done, go to next step

Login to cnMaestro cloud and apply for open beta access by clicking on the ‘Beta’ link at the top right

  • Fill in the requested information. This will generate a support ticket requesting additional SAS and billing information

Respond to the support ticket and wait for confirmation of SAS account creation and cnMaestro migration

  • Could take multiple business days during the beta period and due to the counties of planned operation

Login to cnMaestro cloud and go to Services>CBRS

  • Accept terms and fill in any additional information requested
  • No payment portal is setup during the beta, but this is the area where the payment portal would be located

Devices can now be onboarded into cnMaestro and added into the CBRS services portal for normal CBRS operation

  • Once registered in the SAS, the devices will also be visible in the respective SAS portal
  • See E-Learning and Beta CBRS documentation (located with the beta firmware on the support site) for details