To learn which spectrum is available at its location, a registered CBSD can send a spectrum inquiry request to the SAS

The SAS will respond with:

  • Detailed information about which frequencies are available for the CBSD to use.
  • Additional information which might be useful to the CBSD when it’s selecting a frequency range to transmit on.

Note: The word “channel” is frequently used to describe a 10 MHz segment of the CBRS band.

A channel is marked as unavailable to the CBSD if the SAS is unable to authorize any transmissions on that channel at the CBSD’s location. For example, the SAS is not allowed to authorize transmissions inside of exclusion zones. Otherwise, the SAS indicates that the channel is available for use.

Note: In order to meet operational security requirements from the DoD, Google’s SAS does not indicate which channels are currently affected by Naval operations.

If the spectrum inquiry request was malformed, the SAS will reject the request. Examples of malformed requests include having an invalid frequency range or an invalid CBSD ID.