Relationship between service areas and tracking areas in lte ?

Question

I know UE reports three parameters known as CQI (Channel Quality Indicator) , PMI (Pre-coding Matrix Index) and RI (Rank indicator).
Is it necessary all these three parameters should be reported and all of them have inter dependency and eNodeB considers all the parameters to take its decision ?
I am expecting answer which gives me the complete understanding of all these parameters such as
- When eNodeB configures all these parameters ?
- Can it be configured independently or together ?
- What an eNodeB does after receiving all these parameters ?

Answer 1

The MME pool areas through which the mobile can move without a change of serving MME. Every MME pool area is controlled by one or more MMEs on the network.
The S-GW service areas served by one or more serving gateways S-GW, through which the mobile can move without a change of serving gateway.

The MME pool areas and the S-GW service areas are both made from smaller, non-overlapping units known as tracking areas (TAs). They are similar to the location and routing areas from UMTS and GSM and will be used to track the locations of mobiles that are on standby mode.

Answer 2

"Tracking area" term is used by MME for the mobility purpose of UE and service area is used by SGW to identify that how many eNodeBs of a particular service area is being served. Many to Many relationship between Tracking areas and Service areas. A MME can serve couple of tracking areas. Similarly, a SGW can serve couple of service areas.