CBRS COMPREHENSIVE QUESTIONS AND ANSWERS
SURE A+
✔✔What is a spectrum inquiry request? - ✔✔A message that the CBSD sends to the
SAS after registration in order to find out what frequencies are available.
✔✔What is a grant Request? - ✔✔A request that the CBSD sends to the SAS asking for
permission to transmit at a specific frequency range and power level.
✔✔What is included in a grant response? - ✔✔The SAS includes permission to operate
within the specified parameters sent in the grant request, and includes an ID to identify
this specific grant request.
✔✔What is a heartbeat request? - ✔✔The CBSD heartbeat is sent after all other
registration steps to verify that all information is good to go and it can transmit.
✔✔How often are CBSDs required to heartbeat to the SAS? - ✔✔Every 4 minutes.
✔✔What is the full list of permission and registration steps for a CBSD? - ✔✔1. send
registration request
2. receive registration response
3. send spectrum inquiry request
4. receive spectrum inquiry response
5. send grant request
6. receive grant response
7. send heartbeat request
8. receive heartbeat response
✔✔When sending a request to the SAS, when does the CBSD receive a response
code? - ✔✔Always
, ✔✔How does the SAS receive REG-Conditional parameters? - ✔✔They are given by
the CPI.
✔✔What are the differences and similarities between Category A and B CBSDs? -
✔✔Category A:
- only requires CPI installation if the CBSD cannot determine its own location
- Can be used indoors
- Can be used outdoors if it is below the height limit
- Has a transmit power limit of 20 dBm/MHz and 30dBm/10MHz
Category B:
- Always requires CPI installation
- Cannot be used indoors
- does not have an outdoor height limit
- Has a transmit power limit of 37 dBm/MHz and 47dBm/10MHz
Both:
- Cannot be used on moving objects
- Must communicate with the SAS
✔✔What is the category A CBSD height limit? - ✔✔6 meters
✔✔HAAT - ✔✔Height Above Average Terrain - the height of a CBSD when compared to
its surrounding landscape.
✔✔How is the HAAT calculated? - ✔✔You need to use online tools to calculate the
height above sea level using the CBSDs height above ground, then plug the sea level
height into the FCCs HAAT calculator.
✔✔How does the SAS know what device it is communicating with? - ✔✔Each CBSD is
assigned an FCC ID when it is authorized to be sold, which is used by the SAS to
identify the CBSD device model.
✔✔What is the CBSD ID? - ✔✔This is the ID that the SAS creates for each CBSD using
its FCC ID and Serial Number.
✔✔What is required for installation of a single device with multiple antennas? - ✔✔Each
seperate antenna is seen as a seperate CBSD and will need its own CBSD ID. The
antennas will have the same serial number and will need sector numbers assigned by
the CPI.
✔✔How accurate does the location of a CBSD have to be when reported to the SAS? -
✔✔Latitude and longitude must be within 50 meters and height has to be within 3
meters.
SURE A+
✔✔What is a spectrum inquiry request? - ✔✔A message that the CBSD sends to the
SAS after registration in order to find out what frequencies are available.
✔✔What is a grant Request? - ✔✔A request that the CBSD sends to the SAS asking for
permission to transmit at a specific frequency range and power level.
✔✔What is included in a grant response? - ✔✔The SAS includes permission to operate
within the specified parameters sent in the grant request, and includes an ID to identify
this specific grant request.
✔✔What is a heartbeat request? - ✔✔The CBSD heartbeat is sent after all other
registration steps to verify that all information is good to go and it can transmit.
✔✔How often are CBSDs required to heartbeat to the SAS? - ✔✔Every 4 minutes.
✔✔What is the full list of permission and registration steps for a CBSD? - ✔✔1. send
registration request
2. receive registration response
3. send spectrum inquiry request
4. receive spectrum inquiry response
5. send grant request
6. receive grant response
7. send heartbeat request
8. receive heartbeat response
✔✔When sending a request to the SAS, when does the CBSD receive a response
code? - ✔✔Always
, ✔✔How does the SAS receive REG-Conditional parameters? - ✔✔They are given by
the CPI.
✔✔What are the differences and similarities between Category A and B CBSDs? -
✔✔Category A:
- only requires CPI installation if the CBSD cannot determine its own location
- Can be used indoors
- Can be used outdoors if it is below the height limit
- Has a transmit power limit of 20 dBm/MHz and 30dBm/10MHz
Category B:
- Always requires CPI installation
- Cannot be used indoors
- does not have an outdoor height limit
- Has a transmit power limit of 37 dBm/MHz and 47dBm/10MHz
Both:
- Cannot be used on moving objects
- Must communicate with the SAS
✔✔What is the category A CBSD height limit? - ✔✔6 meters
✔✔HAAT - ✔✔Height Above Average Terrain - the height of a CBSD when compared to
its surrounding landscape.
✔✔How is the HAAT calculated? - ✔✔You need to use online tools to calculate the
height above sea level using the CBSDs height above ground, then plug the sea level
height into the FCCs HAAT calculator.
✔✔How does the SAS know what device it is communicating with? - ✔✔Each CBSD is
assigned an FCC ID when it is authorized to be sold, which is used by the SAS to
identify the CBSD device model.
✔✔What is the CBSD ID? - ✔✔This is the ID that the SAS creates for each CBSD using
its FCC ID and Serial Number.
✔✔What is required for installation of a single device with multiple antennas? - ✔✔Each
seperate antenna is seen as a seperate CBSD and will need its own CBSD ID. The
antennas will have the same serial number and will need sector numbers assigned by
the CPI.
✔✔How accurate does the location of a CBSD have to be when reported to the SAS? -
✔✔Latitude and longitude must be within 50 meters and height has to be within 3
meters.
