Context
For the radio access network (RAN) domain, additional objects are required in AAI to effectively maintain the inventory of a RAN management system, so that this information can be used for various use cases such as cell site map, SON, etc.
Note: The proposed model in this document applies to all radio access technologies e.g. 2G, 3G, 4G, 5G, etc
Additions to AAI Schema
- A new "cell" object (and its relationships) has to be added into AAI schema.
- The existing "site-resource" object can be used to represent PLANNED RAN inventory.
- In the site-resource model, an additional relationship from site-resource to PNF should be added into the schema. This is useful to relate a deployed physical RAN node to a planned one e.g. Radio Unit
- A new relationship between site-resource objects is required, to show the dependancy or relationship between two site-resources e.g. which planned CU will control a planned DU
- A new relationship between VNFs is required to indicate the connection between two virtualised RAN nodes e.g. which CU controls a DU
Representation of Planned RAN Inventory
In this model, RAN planning data is represented as AAI objects such as :
- geo-region (Tracking Area or larger physical site such as Berlin, etc) ,
- complex (Cell Site) and
- site-resource (a planned RAN node e.g. 4G eNB, 5G eNB, etc)
- a new "cell" object which can represent a cell of any radio technology e.g 5g, 4g, etc.
Representing Planned Nodes
A site-resource represents a Planned RAN node
A complex represents a cell-site.
A new "Supports" relationship between site-resource objects can be used to represent the interaction between the planned RAN nodes.
Some example queries are listed below:
As an example, we consider an eNB here, but as stated before, other RAN technologies can be modelled in a similar way.
How to find planned eNBs:
Query all site-resources of type "eNB"
How to find planned CU/DU in an eNB :
Follow the (new) Supports relationship from site-resource of type "eNB" to find the site-resources of type "cu" or "du"
How to find planned eNBs covering a cell-site :
Follow the Uses relationship from Complex to Site-resources of type "eNB"
How to find planned DU covering a cell-site:
Follow the Uses relationship from Complex to Site-resources of type "du"
How to find planned mapping of DU to CU:
Follow the (new) Supports relationships from the site-resource of type "du" , to find the connected site-resources of type "cu"
Note: All new relationships in AAI are indicated in red in the following diagrams
AAI Cell object high level diagram
AAI Cell Model specification
A single Cell object can represent a cell of any radio technology e.g 5G, 4G, etc. The relationships mainly indicate the geographical and tracking areas that this Cell is part of, and the planned and deployed radio resources controlling the cell.
AAI model details
Cell
Cell: object
DESCRIPTION
radio cell of the mobile network operator
PROPERTIES
cell-id: string
unique identifier of the cell (i.e. could be globally unique like NCGI or unique within operator domain like NCI)
cell-local-id: string
unique identifier of the cell within node (like eNodeb, gNodeb)
mno-id: string
operator specific cell identifier
node-id: string
cell's node id (like gNodeb id, eNodeb id)
cell-name: string
individual name of cell
radio-access-technology: string
cell radio access technology (i.e. GSM, UMTS, LTE, NR)
latitude: float
latitude of cell
longitude: float
longitude of cell
azimuth: float
direction of cell beam (range: 0-360)
height: float
cell height above ground
mechanical-tilt: float
mechanical tilt of cell
electrical-tilt: float
electrical tilt of cell
beamwidth: float
horizontal beamwidth of cell
cell-type: string
type of cell (i.e. macro, micro, indoor, outdoor, string)
coverage-area: string
type of coverage area (i.e. urban, suburban, rural, string)
frequency-band: string
cell operating frequency band
mnc: string
operator mobile network code
mcc: string
operator country code
selflink: string
Not mandatory to be used but it could contain a link to additional operator-specific info about the cell e.g. CPS link to additional cell info (it may be a collection of links e.g. operator-specific cell attributes, 3gpp-config, vendor-config, NRCellDU, NRCellCU in CPS)
neighbours: Neighbour[]
Neighbour
Neighbour: object
DESCRIPTION
Cell neighbour relation
PROPERTIES
neighbour-id: string
unique identifier of neighbour relation (i.e. in following format cell.cell-id-neighbour-cell-id)
neighbour-cell-id: string
identifier of the neighbour cell
neighbour-cell-name: string
name of zthe neighbour cell
selflink: string
Not mandatory to be used but this could contain a link to additional info about the neighbour e.g. CPS link to additional neighbour info (i.e. 3gpp NRCellRelation)
AAI Cell object Relationships
Deployed RAN Model
We have taken as example of an eNB (4G) , but other RAN technologies can be modelled in a similar way.
When RAN nodes are deployed, there is often a dependency between nodes that should be represented in AAI. For this reason, a new relationship called "Supports" should be introduced between generic-vnf objects, as shown below in an example RAN eNB representation.
