In SIB1, there are some information relevant to SI message.
one S1 message can contains a number of SIBs inside same message.
As we know, SIB2 to SIB13 are configurable in term of periodicity .
All the SIBs which have same periodicity kept into same SI message.
SIB1 can carry information a number of SI message. There is a concept of order.
First SI message in Scheduling info list has order 1, Second SI message has order 2 and so on.
SI Window size means how many times it will repeated so that UE can decode successfully required system information.
To acquire such system information, UE should aware that on which radio frame as well as on which sub frame of that radio frame SIB information will be available and how many times it will be repeatedly send by eNodeB.
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