NAS control
indication manual mode
to user
CM requests
radio measurements
PLMN selected
registration area changes
PLMN available
location registration
automatic mode
response
: if the UE is in the
PLMN selection and reselection;
Cell selection and reselection;
Location registration.
if the UE is in the states:
NAS control
indication manual mode
to user
CM requests
radio measurements
PLMN selected
registration area changes
PLMN available
location registration
automatic mode
response
: if the UE is in the
PLMN selection and reselection;
Cell selection and reselection;
Location registration.
if the UE is in the states:
in automatic PLMN selection operation mode
HPLMN Search Period Timer 6 .. 480 minutes Default: 60 minutes
BCCH: Cell Access Restriction
- acceptable - suitable - barred - reserved
suitable for selection and
Cell „barred“
reselection
not barred
not reserved
not reserved
not barred
not reserved
reserved
not barred
reserved
---
barred
---
---
suitable for AC 11 or 15 in HPLMN otherwise „barred“
Not suitable ‟ not even for emergency call
suitable cell
suitable cell
WCEL:
Defines whether the cell is barred or not. A barred cell is a cell where a UE is not allowed to camp on. This parameter is part of SIB 3. 0 (Barred), 1 (Not barred); default: 1. WCEL:
When the cell is barred, UE regards the cell barred condition valid for a number of seconds defined by the value of 'Cell barred period'. This parameter is part of SIB 3. [10, 20, 40, 80, 160, 320, 640, and 1280] seconds; default: 40 seconds. WCEL:
Defines whether the cell is reserved for operator use. This parameter is part of SIB 3. 0 (Reserved), 1 (Not reserved); default: 1. WCEL:
Defines whether intra-frequency cell re-selection is allowed when the cell is barred. This parameter is part of SIB 3/4. 0 (Allowed), 1 (Not allowed); default: 0.
RAT(s) associated with the selected PLMN forbidden registration areas
PLMN selection attempts to find suitable cells
list of equivalent PLMNs
go here whenever a new PLMN is selected
cell information stored for the PLMN
Stored Information Cell Selection
no cell information stored for the PLMN
1
Initial Cell Selection
no suitable cell found
no suitable cell found suitable cell found
Cell Selection when leaving connected mode
return to idle mode
Connected Mode
suitable cell found
leave idle mode
suitable cell found
Camped normally
rigger
NAS registration rejected
suitable cell selected
Cell Reselection Evaluation Process
no suitable cell found
no suitable cell found
go here when no USIM in the UE
1
Any Cell Selection
USIM inserted
no acceptable cell found an acceptable cell found
Cell Selection when leaving connected mode
return to idle mode
Connected Mode (Emergency calls only)
acceptable cell found
Camped on Any Cell
leave idle mode
suitable cell found
1
acceptable trigger
cell selected
Cell Reselection Evaluation Process
no acceptable cell found
(adopted from TS 25.305 V3.11.0 chap. 5.5.2)
(dB) (CPICH Ec/N0)
(‟24...0)
(dBm) (‟115... ‟25)
suitable cell?
CPICH RSCP
Cell size defining parameters: Qrxlevmin Qqualmin
I am outside
I am inside, but have not enough power -50 .. 33 dBm
or
active set cells as candidates for cell selections; if not, then Stored information cell selection
WCEL:
The minimum required RX level in the cell. This parameter is part of SIB 3. [-115 ... ‟25] dBm, step 2 dBm; default: -115 dBm. WCEL:
The minimum required quality level in the cell (Ec/No). This parameter is part of SIB 3. [-24 ... 0] dB, step 1 dB, default: -20 dB. WCEL:
This parameter defines the maximum transmission power level a UE can use on PRACH. The value of the parameter also effects the cell selection and reselection procedures. The value of the parameter is sent to UE in the Cell selection and re-selection of SIB 3 and 4 of the serving cell. [..]
measurement thresholds
measurement thresholds
S-Criterion fulfilled
S-Criterion fulfilled
H-Criterion for fast moving UEs
for slow moving UEs
R-Criterion
R-Criterion
R-Criterion
cell ranking
cell ranking
cell ranking
Example: Nokia Sintrasearch = 4dB, Sintersearch = 2dB, Ssearch_RAT = 0dB
Where to perform measurements
WCEL:
This parameter indicates whether the serving cell belongs to a Hierarchical Cell Structure (HCS). This parameter is part of SIB 11/12. 0 (HCS not used), 1 (HCS in use); default: 0. WCEL:
The threshold for intra-frequency measurements, and for the HCS measurement rules. This parameter is part of SIB 3. [0 ... 20] dB, step 2 dB, default: 4 dB. WCEL:
The threshold for inter-frequency measurements, and for the HCS measurement rules. This parameter is part of SIB 3. [0 ... 20] dB, step 2 dB, default: 2 dB. WCEL:
The RAT-specific threshold for inter-RAT measurement rules. This parameter is part of SIB 3. [0 ... 20] dB, step 2 dB, default: 0 dB.
if
if
Example: Nokia Sintrasearch = 4dB, Sintersearch = 2dB, Ssearch_RAT = 0dB, SsearchHCS = 1dB
if
if
Example: Nokia
measure on all Inter-RAT cells
Sintrasearch = 4dB,
Sintersearch = 2dB,
Ssearch_RAT = 0dB,
Slimit, searchRAT = 2dB
SsearchHCS = -1dB,
SHCS_RAT = 1dB
WCEL:
The RAT specific threshold for inter-RAT measurement rules. This parameter is par t of SIB 3. [-1 ... 91] dB, step 2 dB, default: -1 dB (UE sets this value to 0). WCEL:
Threshold for skipping inter-RAT measurement rules in HCS. Above this RAT specific threshold in the serving UTRA cell, the UE does not need to perform any inter-RATm measurements. This parameter is part of SIB 3. [0 ... 20] dB, step 2 dB, default: 2 dB. WCEL:
Threshold for intra- and inter-frequency measurement rules in HCS. Below this limit in the serving cell, the UE initiates measurements of all intra and inter-frequency neighbouring cells of the serving cell. This parameter is part of SIB 3. [-1 ... 91] dB, step 2 dB, default: -1 dB (UE sets this value to 0).
Example: Nokia TCRmax = 60s, NCR = 8, TCRmaxHyst = 0s
NCR = cell reselection threshold (default: 8) TCRmax = time period
measures neighbouring cells with equal or
priorizes cells with lower HCS priority
lower HCS priority
for re-selection
WCEL:
This parameter defines the maximum number of cell reselections. If the number of cell reselections during the TCrmax time period exceeds the value of NCr, high mobility has been detected. Not used if TCrmax equals 'not used‚ This parameter is part of SIB 3.
[1 ... 16], default: 8. WCEL:
The duration for evaluating the allowed amount of cell reselections. If the number of cell reselections during the time period defined by Tcrmax exceeds Ncr, high mobility has been detected. This parameter is part of SIB 3. [0 (= not used), 30, 60, 120, 180, 240] seconds, default: 60 seconds. WCEL:
Cell reselection hysteresis for reverting from UE high-mobility measurements. The additional time period before UE reverts to low-mobility measurements. This parameter is part of SIB 3. [0, 10, 20, 30, 40, 50, 60, 70] seconds, default: 0 seconds.
measurement thresholds S-Criterion fulfilled
for fast moving UEs
for slow moving UEs
R-Criterion cell ranking
R-Criterion
R-Criterion
cell ranking
cell ranking
time
WCEL:
This parameter defines the HCS priority level for a cell. Value 0 indicates the lowest HCS priority and value 7 indicates the highest HCS priority. [0 ... 7], default: 0. WCEL:
Quality threshold level for applying prioritised hierarchical cell re-selection for a cell. Part of HCS Serving cell information (
). This parameter is part of SIB 3.
[-24 ... 0] dB, step 0.5 dB, default: -24 dB.
HOPS: Defines the threshold level which must be exceeded by the CPICH Ec/No of the intra-frequency neighbouring cell before the hierarchical cell re-selection becomes possible (
).
[-24 ... 0] dB, step 0.5 dB, default: -24 dB. HOPI:
[-24 ... 0] dB, step 0.5 dB, default: -24 dB.
HOPG:
[-110 ... -37] dBm, default: -110 dBm.
HOPS: This parameter is used in the cell ranking between cells when the intra-frequency neighbour cell has the same HCS priority level as the serving cell. [3, 6, 9, 12, 15, 18, 21, 100 (Infinity)] dB, default: 3 dB. HOPI:
HOPG:
HOPS: This parameter is used in the cell ranking between WCDMA cells when the intra-frequency neighbour cell has the same HCS priority level as the serving cell. [2, 3, 4, 6, 8, 10, 12, 100 (Infinity)] dB, default: 2 dB. HOPI:
HOPS: Defines the time period during which the Temporary Offset 1/2 is applied in the cell re-selection procedure for the intra-frequency neighbour cell in question. [0 ... 60] seconds, step 10 seconds, default: 0. HOPI:
HOPG:
temp. offset only used with HCS
WCEL:
Qhyst1 is used for TDD and GSM cells, and for FDD cells when cell selection and re-selection quality measure is set to CPICH RSCP (CPICH Ec/No) (
/
). This parameter is part of SIB 3.
[0 ... 40] dB, step 2 dB, default: 4 dB.
HOPS: This parameter is used in the cell re-selection and ranking between WCDMA cells. The value of this parameter is subtracted from the measured CPICH RSCP (CPICH Ec/No) of the intra-frequency neighbour cell before the UE compares the quality measure with the cell re-selection/ranking criteria. [-50 ... 50] dB, default: 0 dB. HOPS:
HOPG:
WCELL:
The UE triggers the reselection of a new cell if the cell reselection criteria are fulfilled during the time interval Treselection. This parameter is part of SIB 3. [0 ... 31] seconds, default: 0 seconds. The remaining parameters were already specified under Nokia Parameters for Cell Reselection (Part IV).
DRX cycle
start measurement on neighbouring cells
if UE RRC idle UE initiates cell selection procedures for the selected PLMN
DRX cycle At least one CPICH Ec/Io measurement CPICH RSCP measurement S criterion evaluation
if still no suitable cells UE “out of service area”
3 dB
cycle At least one
UE is capable of evaluating that an intra-frequency
CPICH Ec/Io measurement, or
cell has become better ranked (if Treselection = 0)
CPICH RSCP measurement
within TmeasureFDD
3 dB for CPICH Ec/Io 5 dB for CPICH RSCP
At least one
UE is capable of evaluating that an inter-frequency
CPICH Ec/Io measurement or
cell has become better ranked (if Treselection = 0)
CPICH RSCP measurement
within (Ncarrier -1) * TmeasureFDD
Each GSM neighbour GSM BCCH carrier RSSI
BSIC at least every 30 seconds for each of the 4 strongest GSM BCCH carriers
0.08
4
0.64 (8 DRX cycles)
2.56 (32 DRX cycl)
2.56 (32 DRX cycl)
0.16
4
0.64 (4)
2.56 (16)
2.56 (16)
0.32
4
1.28 (4)
5.12 (16)
5.12 (16)
0.64
4
1.28 (2)
5.12 (8)
5.12 (8)
1.28
2
1.28 (1)
6.4 (5)
6.4 (5)
2.56
2
2.56 (1)
7.68 (3)
7.68 (3)
5.12
1
5.12 (1)
10.24 (2)
10.24 (2)
In idle mode, UE supports DRX cycles lengths 0.64, 1.28, 2.56 and 5.12 s
(DRX cycle length table source: TS 25.133 V3.11.0 chap. 4.2.2.1)