Handling Process
1. AbsolutePriority-based Inter-Frequency Cell Reselection
All thefollowing conditions must be met before absolute priority-based inter-frequencycell
reselection can be used:
· Thelicense is activated for WRFD-020126 Mobility between UMTS and LTE Phase1.
· TheNodeB complies with 3GPP Release 8 or later.
ADD UNODEB: NODEBID=XXXX, NODEBNAME="XXXX", NODEBPROTCLVER=R9;
· TheUE complies with 3GPP Release 8 or later.
The supportForPriorityReselectionInUTRAN=turefield in the RRC Connection Setup Complete
message supports absolutepriority-based inter-frequency cell reselection.
· ThePrioReselectSwitch (BSC6900,BSC6910) parameter in the ADD UCELLSELRESEL or
MOD UCELLSELRESELcommand is set to ON.
MOD UCELLSELRESEL: CELLID= XXX, SPRIORITY=X ,PrioReselectSwitch= UTRAN_RESELECT_SWITCH-1;
· SIB19 under the SibCfgBitMap(BSC6900,BSC6910) parameter in the ADD UCELLSIBSWITCH or MOD
UCELLSIBSWITCHcommand is selected.
MOD UCELLSIBSWITCH: CELLID= XXX, SIBCFGBITMAP=SIB19-1;
· UMTSinter-frequency information is configured in SIB19 by running the ADD
UCELLINTERFREQPRIOINFOor MODUCELLINTERFREQPRIOINFO command.
（Assumethat there are three frequencies, CELLID= XXX is F1, and F2F3 is available.
Thepriorities of other frequencies are broadcast in the current cell.）
ADD UCELLINTERFREQPRIOINFO: CELLID= XXX, DLUARFCN=F1,UTRANFREQPriority=X;
ADD UCELLINTERFREQPRIOINFO: CELLID= XXX, DLUARFCN=F2, UTRANFREQPriority=X;
ADD UCELLINTERFREQPRIOINFO: CELLID= XXX, DLUARFCN=F3,UTRANFREQPriority=X;
2. Noabnormal during parameter check. (Taking one sector as an example)：
ADD UNODEB:NODEBID=31400,LOGICRNCID=10,
NODEBNAME="3140AM",TNLBEARERTYPE=IP_TRANS, NODEBPROTCLVER=R9;
ADD UCELLSETUP:CELLID=5140, BANDIND=Band1,
UARFCNDOWNLINK=10638,MAXTXPOWER=460, PSCRAMBCODE=272,
NODEBNAME="3140AM";
ADD UCELLSETUP:CELLID=8140, BANDIND=Band1,
UARFCNDOWNLINK=10663,MAXTXPOWER=460, PSCRAMBCODE=272,
NODEBNAME="3140AM";
ADD UCELLSETUP:CELLID=14140,BANDIND=Band8,
UARFCNDOWNLINK=3015, MAXTXPOWER=460, PSCRAMBCODE=272,
NODEBNAME="3140AM";
ADD UCELLSETUP:CELLID=11140,BANDIND=Band1, UARFCNDOWNLINK=10788,
MAXTXPOWER=460, PSCRAMBCODE=272,NODEBNAME="3140AM";
ADD UCELLSELRESEL:CELLID=5140, QUALMEAS=CPICH_ECNO, QQUALMIN=-
18,QRXLEVMIN=-58, IDLESINTRASEARCH=5, IDLESINTERSEARCH=4,
CONNSINTRASEARCH=5,CONNSINTERSEARCH=4,
SPRIORITY=3,THDPRIORITYSEARCH1=4, THDPRIORITYSEARCH2=4,
THDSERVINGLOW=6,
THDSERVINGLOW2=2,PRIORESELECTSWITCH=UTRAN_RESELECT_SWITCH-1;
ADD UCELLSELRESEL:CELLID=8140, QUALMEAS=CPICH_ECNO, QQUALMIN=-
18,QRXLEVMIN=-58, IDLESINTRASEARCH=5, IDLESINTERSEARCH=4,
CONNSINTRASEARCH=5,CONNSINTERSEARCH=4, SPRIORITY=3,
THDPRIORITYSEARCH1=4,THDPRIORITYSEARCH2=4, THDSERVINGLOW=6,
THDSERVINGLOW2=2,PRIORESELECTSWITCH=UTRAN_RESELECT_SWITCH-1;
ADD UCELLSELRESEL:CELLID=14140,QUALMEAS=CPICH_ECNO, QQUALMIN=-18,
QRXLEVMIN=-58, IDLESINTRASEARCH=5,IDLESINTERSEARCH=4,
CONNSINTRASEARCH=5, CONNSINTERSEARCH=127,
SPRIORITY=2,THDPRIORITYSEARCH1=2, THDPRIORITYSEARCH2=2,
THDSERVINGLOW=1,
THDSERVINGLOW2=2,PRIORESELECTSWITCH=UTRAN_RESELECT_SWITCH-1;
ADD UCELLSELRESEL:CELLID=11140,QUALMEAS=CPICH_ECNO, QQUALMIN=-18,
QRXLEVMIN=-58, IDLESINTRASEARCH=5,IDLESINTERSEARCH=4,
CONNSINTRASEARCH=5, CONNSINTERSEARCH=4, SPRIORITY=3,
THDPRIORITYSEARCH1=4,THDPRIORITYSEARCH2=4, THDSERVINGLOW=6,
THDSERVINGLOW2=2,PRIORESELECTSWITCH=UTRAN_RESELECT_SWITCH-1;
ADD UCELLSIBSWITCH: CELLID=5140,SIBCFGBITMAP=SIB19-1;
ADD UCELLSIBSWITCH: CELLID=8140, SIBCFGBITMAP=SIB19-1;
ADD UCELLSIBSWITCH:CELLID=14140,SIBCFGBITMAP=SIB19-1;
ADD UCELLSIBSWITCH:CELLID=11140,SIBCFGBITMAP=SIB19-1;
ADDUCELLINTERFREQPRIOINFO:CELLID=5140,
DLUARFCN=10638,UTRANFREQPRIORITY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=5140,
DLUARFCN=10663,UTRANFREQPRIORITY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=5140,
DLUARFCN=10788,UTRANFREQPRIORITY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=5140, DLUARFCN=3015,
UTRANFREQPRIORITY=2;
ADD
UCELLINTERFREQPRIOINFO:CELLID=8140,DLUARFCN=10663,UTRANFREQPRIORITY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=8140,
DLUARFCN=10638,UTRANFREQPRIORITY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=8140,
DLUARFCN=10788,UTRANFREQPRIORITY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=8140, DLUARFCN=3015,
UTRANFREQPRIORITY=2;
ADDUCELLINTERFREQPRIOINFO:CELLID=11140,DLUARFCN=10788,UTRANFREQPRIORI
TY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=11140,DLUARFCN=10663,UTRANFREQPRIORI
TY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=11140,DLUARFCN=10663,UTRANFREQPRIORI
TY=3;
ADD
UCELLINTERFREQPRIOINFO:CELLID=11140,DLUARFCN=3015,UTRANFREQPRIORITY=2;
ADDUCELLINTERFREQPRIOINFO:CELLID=14140,DLUARFCN=3015,
UTRANFREQPRIORITY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=14140,DLUARFCN=10663,UTRANFREQPRIORI
TY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=14140,DLUARFCN=10788,UTRANFREQPRIORI
TY=3;
ADDUCELLINTERFREQPRIOINFO:CELLID=14140,DLUARFCN=10638,UTRANFREQPRIORI
TY=3;
3. TheUElog analysis shows that the UE has read SIB19 system information and take
thepriorities for U900 and U2100 frequencies.
4. But itcan confirm that the accessed cell is also U900 cell (CELLID=14140) by the
RRCConnection Setup information.
5. TheRRC Connection Setup Complete message does not take
thesupportForPriorityReselectionInUTRAN indicating that the UE does not supportinter-
frequency cell reselection based on absolute priorities. Therefore, theUE cannot be reelected to
the U2100 and can only access the U900.
Supplementary information：
Measurement Rules
SIB19 carriesthe absolute priority of the serving UMTS cell, the absolute priorities ofinter-
frequency UMTS cells, and the cell reselection thresholds. Upon receivingSIB19, the UE
triggers inter-frequency measurement according to the followingrules:
· TheUE measures the signal quality of UMTS cells working at frequencies that havehigher
absolute priorities than the frequency of the serving cell at aninterval specified by
Thigher_priority_search.
· IfSrxlevServingCell is less than or equal to Sprioritysearch1or SqualServingCell is less than or equal to
Sprioritysearch2,the serving cell has poor signal quality. In this case, the UE starts measuringthe
signal quality of cells working at frequencies that have the same or lowerabsolute priorities than
the frequency of the serving cell.
· IfSrxlevServingCell is greater than Sprioritysearch1 andSqualServingCell is greater than Sprioritysearch2,
theserving cell has good signal quality. In this case, the UE does not measure thesignal quality
of cells working at frequencies that have the same or lowerabsolute priorities than the frequency
of the serving cell.
The variablesin the preceding rules are described in Table 4-10.
Table4-10 Variables involved inmeasurement rules
Variable Parameter Name Parameter ID Description
Absolute priority of the Absolute priority SPriority (BSC6900, Absolute priority of the serving
serving UMTS cell level of the BSC6910) cell when a UE performs cell
serving cell reselection
Absolute priority of the Absolute Priority UTRANFREQPriority Absolute priority of the UTRA
UTRA frequency of UTRA (BSC6900, frequency
Frequency BSC6910)
SrxlevServingCell - - TX level of the serving cell
received by the UE (dBm)
It is defined as follows:
SrxlevServingCell = RSCP of the
serving cell measured by the
UE – Qrxlevmin (BSC6900,
BSC6910)
Sprioritysearch1 RSCP threshold ThdPrioritySearch1 CPICH RSCP threshold for
for low-prio-freq (BSC6900, determining whether a UE
measurement BSC6910) performs measurements of low-
initiation priority frequencies.
The setting of this parameter
also affects how often high-
priority cells are measured. A
larger parameter value makes it
harder for UEs to perform
measurements on high-priority
cells.
SqualServingCell - - Quality value of the serving cell.
It is defined as follows:
SqualServingCell = Ec/No of the
serving cell measured by the
UE – Qqualmin (BSC6900,
BSC6910)
Sprioritysearch2 Ec/No threshold ThdPrioritySearch2 CPICH Ec/No threshold for
for low-prio-freq (BSC6900, determining whether a UE
measurement BSC6910) performs measurements of low-
initiation priority frequencies.
The setting of this parameter
also affects how often high-
priority cells are measured. A
Variable Parameter Name Parameter ID Description
larger parameter value makes it
harder for UEs to perform
measurements on high-priority
cells.
Thigher_priority_searc - - According to section 4.2.2
h "Requirements" in 3GPP TS
25.133 V11.5.0, the value of
Thigher_priority_search (in
seconds) is the product of
frequencies multiplied by 60.
Absolute Priority-based Criteria for Inter-Frequency CellReselection
SIB19 carriesthe absolute priority of the serving UMTS cell, the absolute priorities ofinter-
frequency UMTS cells, and the cell reselection thresholds. The UEperforms inter-frequency cell
reselection based on these absolute priorities.
The section"5.2.6.1.4a Absolute priority based criteria for inter-frequency andinter-RAT cell
reselection" in 3GPP TS 25.304 V11.3.0 specifies five setsof criteria for cell reselection based
on the absolute priorities. Table 4-11 lists the applicableRATS of involved criterion.
Table4-11 Applicable target RATS ofabsolute priority-based criteria for cell reselection
Criterion Applicable Target RAT
Criterion 1 GSM, inter-frequency UMTS, and LTE
Criterion 2 Inter-frequency UMTS
Criterion 3 GSM, inter-frequency UMTS, and LTE
Table4-12 Conditions for applying thecriteria
Criterion Condition (Combined)
Criterion 1 · The absolute priority of an inter-frequency UMTS cell is higher than that of
the serving UMTS cell.
· SrxlevnonServingCell has remained above the value of Threshhigh for a period of
time longer than the value of Treselections.
Criterion 2 · The absolute priority of an inter-frequency UMTS cell is equal to that of the
serving UMTS cell.
· SrxlevnonServingCell has been remained greater than Threshlow for a period of time
longer than Treselection.
· SrxlevServingCell has been remained below Threshserving,low for a period of time
longer than Treselection, or SqualServingCell has been remained below or equal to 0 for
a period of time longer than Treselection.
Criterion 3 · The absolute priority of an inter-frequency UMTS cell is lower than that of the
serving UMTS cell.
Criterion Condition (Combined)
· SrxlevnonServingCell has been remained greater than Threshlow for a period of time
longer than Treselection.
· SrxlevServingCell has been remained below Threshserving,low for a period of time
longer than Treselection, or SqualServingCell has been remained below or equal to 0 for
a period of time longer than Treselection.
NOTE:
The absolute priority of aninter-frequency UMTS cell is specified by the
UTRANFREQPriority(BSC6900, BSC6910)parameter. The absolute priority of the serving
UMTS cell is specified by the SPriority (BSC6900, BSC6910)parameter.
Table 4-13 describes thevariables in criterion 2
Table4-13 Variables involved incriterion 2
Variable Parameter Name Parameter ID Description
SrxlevServingCell - - TX level of the serving cell received by
the UE (dBm)
It is defined as follows:
SrxlevServingCell = RSCP of the serving
cell measured by the UE – Qrxlevmin
(BSC6900, BSC6910)
SqualServingCell - - Quality value of the serving cell.
It is defined as follows:
SqualServingCell = Ec/No of the serving
cell measured by the UE – Qqualmin
(BSC6900, BSC6910)
SrxlevnonServingCell - - TX level of a UE in a cell served by a
UMTS frequency (dBm)
It is defined as follows:
SrxlevnonServingCell = RSCP measured by
a UE in an inter-frequency UMTS cell –
QrxlevminFDD (BSC6900, BSC6910)
Threshhigh Level Thld for ThdToHighUMTS Signal quality threshold for thye UE to
Cell Reselect to (BSC6900, reselect to a higher-priority inter-
Higher Priority BSC6910) frequency UMTS cell. The signal
quality threshold is contained in the
SIB19 message. When the priority of
an inter-frequency UMTS cell is higher
than the serving cell and the signal
quality of this inter-frequency UMTS
cell is better than the value of this
Variable Parameter Name Parameter ID Description
parameter, the UE reselects to this
inter-frequency UMTS cell. For details
about this parameter, see 3GPP TS
25.331.
Threshlow Level Thld for ThdToLowUMTS Signal quality threshold for the UE to
Cell Reselect to (BSC6900, reselect to a lower-priority inter-
Lower Priority BSC6910) frequency UMTS cell. The signal
quality threshold is contained in the
SIB19 message. When the priority of
an inter-frequency UMTS cell is lower
than the serving cell and the signal
quality of this inter-frequency UMTS
cell is better than the value of this
parameter, the UE reselects to this
inter-frequency UMTS cell. For details
about this parameter, see 3GPP TS
25.331.
Treselection - - Cell reselection delay. It is defined as
follows: Treselections (BSC6900,
BSC6910) x
InterFreqTreselScalingFactor
(BSC6900, BSC6910).
Threshserving,low RSCP threshold ThdServingLow CPICH RSCP value of the serving cell
for low-prio-freq (BSC6900, for cell selection towards the target cell
reselection BSC6910) using a lower-priority frequency. After
a UE starts measuring the cell
operating at the frequency with a lower
priority, if the signal quality of the
serving cell remains below this
threshold and SrxlevnonServingCell of the
cell operating at the target frequency is
greater than Threshlow, the UE
performs cell reselection to the cell
operating at the frequency with a lower
priority. A larger parameter value
makes it easier for UEs to initiate
priority-based cell reselections. A
smaller parameter value makes it more
difficult for UEs to initiate priority-based
cell reselections.
Criteria for Target Cell Reselection
The criteriafor reselecting a target cell are as follows:
· Ifcriterion 1 is fulfilled, the UE reselects a UMTS cell operating on a frequencywith a higher
absolute priority.
· Ifcriterion 2 is fulfilled, the UE reselects a UMTS cell operating on a frequencywith the
same absolute priority.
· Ifcriterion 3 is fulfilled, the UE reselects a UMTS cell operating on a frequencywith a lower
absolute priority.
· Ifnone of the preceding criteria is fulfilled, the UE camps on the original cell.
If there aremultiple candidates, the UE reselects the cell with the largest SrxlevnonServingCellvalue.
Root Cause
UE didn’t supportsabsolute priority-based inter-frequency cell reselection and so cannot trigger
absolutepriority-based inter-frequency cell reselect form U900 to U2100.
Solution
UE didn’t supportsabsolute priority-based inter-frequency cell reselection and so cannot trigger
absolutepriority-based inter-frequency cell reselect form U900 to U2100.
Suggestions and Summary
Currently, only a few terminals support this function: absolutepriority-based inter-frequency cell
reselection. (Through check the U900traffic changes in Modify those parameters in the test
phase to estimate thepercentage of the terminal.)
Suggest Cell barred indicator for SIB3（IdleCellBarred=BARRED）forU900 to fulfill the
customer's demands.
Change the policy to preferential camping on the U2100 andopen WRFD-150232 Multiband
DirectRetry Based on UE Location
