Before it can initiate the grant procedure, the CBSD must be registered with the SAS.
The CBSD determines the operational parameters that will be used in the grant request and initiates the grant procedure by sending a grant request.
When the grant request is successful and the CBSD receives a valid heartbeat response, the CBSD is authorized to transmit using the parameters specified in the request.
The 7705 SAR-Hmc supports the following parameters in a grant request:
CBSD ID
operational parameters:
maximum EIRP — the CBSD maximum EIRP, determined by calculating the sum of the antenna-gain and max-tx-power values configured in the CLI. This total must be within the range expected by the SAS for the CBSD category.
operational frequency range — this information is retrieved from the cellular interface when the CBSD attaches to the network
The SAS sends the CBSD a grant response that contains the following parameters:
CBSD ID
grant ID
grant expire time
heartbeat interval
response — an indication of whether the grant request is approved
If the grant ID is included in the grant response, the grant request succeeded. As soon as the grant request succeeds, the CBSD uses the heartbeat interval parameter to start the heartbeat procedure. The heartbeat is needed in order for the grant to be authorized.
The CBSD uses the grant expire time parameter to determine when the grant expires. The 7705 SAR-Hmc stores this value and sets a timer equal to the expiry time minus 1 h minus the current time. When this timer expires, there is 1 h left before the grant expires and the 7705 SAR-Hmc sets the grantRenew flag to attempt a grant renewal. If the grant is not renewed, the grant request process is restarted.
If the SAS determines an error in the grant request and does not include a grant ID parameter in its response, the grant request failed. The 7705 SAR-Hmc retries the request every 60 s.