System Information Block Type 3 or with shortened version SIB3 contains common information for Intra-Frequency, Inter-Frequency and Inter-Technology cell re-selection parameters. But these parameter values are not applied in all re-selection scenarios. SIB3 is transmitted from the network to UE through BCCH -> DL-SCH -> PDSCH channels.

Here the list of carried information from the network to UE through SIB3:

Cell Reselection Info Common:
q-Hyst: hysteresis value applied to serving cell for evaluating cell-reselection ranking criteria. It is for cell reselection when RSRP values are used in the evaluation.
t-Evaluation: specifies the duration for evaluation. Value in seconds.
t-Hyst Normal: the additional duration for evaluating criteria to enter normal mobility state. Specifies the additional time period for evaluating criteria to enter Normal-mobility state. Value in seconds, s30 corresponds to 30 seconds and so on.
n-cell Change Medium: specifies the number of cell reselections within t-Evaluation to enter Medium-mobility state.
n-cell Change High: specifies the number of cell reselections within t-Evaluation to enter High-mobility state.
sf-Medium: speed-dependent scaling factor for Qhyst in Medium-mobility state.
sf-High: speed-dependent scaling factor for Qhyst in High-mobility state.

Cell Reselection Serving Frequency Info:
s-NonIntra Search: measurement triggering threshold for inter-frequency and inter-RAT measurements with lower or equal priority. Actual value in dB is obtained by multiplying by 2.
Thresh Serving Low: threshold for serving frequency used in evaluation of reselection towards lower priority E-UTRAN frequency. Actual value in dB is obtained by multiplying by 2.
Cell Reselection Priority: cell reselection priority of the serving frequency. 0 indicates the lowest priority.

Intra-Freq Cell Reselection Info:
q-RxLev Min: minimum required received RSRP level for intra-frequency E-UTRA cell re-selection. Actual value in dBm is obtained by multiplying by 2.
p-Max: this parameter is used to limit the allowed UE uplink transmission power on the serving cell.
s-IntraSearch: indicates the measurement triggering threshold for reselection to intra-frequency cells.
Allowed Meas Bandwidth: indicates the measurement bandwidth on the serving frequency on which the UE camps. It is used in intra-frequency measurements for cell reselection.
Presence Antenna Port1: indicates whether all the intra-frequency neighboring cells are configured with at least two antenna ports:
– TRUE when all the intra-frequency neighboring cells are configured with at least two antenna ports.
– FALSE when one of the intra-frequency neighboring cells is configured with only one antenna port.

Neigh Cell Config: provides the information related to MBSFN and TDD UL/DL configuration of neighbor cells:
– “00” some neighboring cells have the same MBSFN sub-frame configuration as the serving cell.
– “01” none of the neighboring cells is configured with MBSFN sub-frames.
– “10” MBSFN sub-frame configurations of all neighboring cells are the same as the serving cell.
– “11” some neighboring cells have different UL-DL configurations from the serving TDD cell.

t-Reselection EUTRA: cell reselection timer for intra frequency E-UTRA cell reselection. Value in seconds.
sf-Medium: specifies scaling factor for intra-frequency t-Reselection EUTRA in Medium-mobility state. Value oDot25 corresponds to 0.25, oDot5 corresponds to 0.5 etc.
sf-High: specifies scaling factor for intra-frequency t-Reselection EUTRA in High-mobility state. Value oDot25 corresponds to 0.25, oDot5 corresponds to 0.5 etc.

SIB3 carried information:

Example for SIB3, taken from drive-test tool:

System Information Block 3
q-Hyst : dB4
s-NonIntraSearch : 2
threshServingLow : 1
cellReselectionPriority : 5
q-RxLevMin : -60
p-Max : 23
s-IntraSearch : 31
presenceAntennaPort1 : False
neighCellConfig
Binary string (Bin) : 01
[0 ] : 0
[1 ] : 1
t-ReselectionEUTRA : 1
t-ReselectionEUTRA-SF
sf-Medium : lDot0
sf-High : oDot75

* Note: there are some parameters which might not be seen in the message list from drive-test tool, so it means this parameter was not configured in the network by the engineers.

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