LTE: How different threshold values are derived for different event like A1, A2, A3, A4 and A5 ?

Question

I was going through the measurement configuration sends from eNodeB to UE in RRC Connection Reconfiguration message.
I saw that multiple events have been defined and are used. Couple of parameters are considered to detect entering and leaving condition of an event for example event A1. Now I have a question "Threshold and Hys values are same for all the cell or it may different". Does the standard define the value of all these parameters or network operator defines ? If network operator does then what are points to derive these values ?

Answer 1

Hi ganesh,

Hys and thrshld is not same for all the cell. If it is same there is no use to send these information to UE. Also no standard defines the value , instead it defines the range of values. operator can select the range of values for both. Based on statistics of the deployment area operator will configure through OAM. How exactly they derive is implementation specific but some factors includes in calculations are coverage area, density, obstacles of the deployment area,availability of other cells etc.

Answer 2

Threshold it's a target for change condition, hysterisis if an margin Gain for add to a threshold for avoid ping pong phenomenal. Both are define by the operator for optimized .