ZGO-02-02-002 Dynamic
Handover Priority Algorithm
Feature Guide
ZGO-02-02-002 Dynamic Handover Priority Algorithm
ZTE Confidential Proprietary 1
ZGO-02-02-002 Dynamic Handover Priority Algorithm
Version Date Author Reviewer Notes
V1.0 2013/11/4
Hua Zhibin,
Zhang
Henglong
Gu Yuhui New
© 2014 ZTE Corporation. All rights reserved.
ZTE CONFIDENTIAL: This document contains proprietary information of ZTE and is not to be disclosed or used
without the prior written permission of ZTE.
Due to update and improvement of ZTE products and technologies, information in this document is subjected to
change without notice.
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TABLE OF CONTENTS
1 Feature Attribute ............................................................................................... 5
2 Overview ............................................................................................................ 5
2.1 Feature Introduction ............................................................................................. 5
2.2 License Control .................................................................................................... 6
2.3 Correlation with Other Features ........................................................................... 6
3 Technical Description ....................................................................................... 6
3.1 Handover type classify ......................................................................................... 7
3.2 Traffic value for the target adjacent cells .............................................................. 8
3.3 Filter the high load target adjacent cells ............................................................... 9
3.4 Calculate the dynamic priority .............................................................................. 9
3.5 Adjacent cells queuing ....................................................................................... 10
4 Parameters and Configurations ..................................................................... 11
4.1 Parameter List ................................................................................................... 11
4.2 Parameter Configuration .................................................................................... 11
4.2.1 Allow dynamic adjustment of handover priority .................................................. 11
4.2.2 Minimal resource threshold ................................................................................ 12
4.2.3 Priority of handover ............................................................................................ 12
4.2.4 Difference of dynamic priority ............................................................................. 13
4.2.5 Target cell traffic threshold ................................................................................. 13
4.2.6 Dynamic Priority NCell Traffic Threshold ............................................................ 14
4.2.7 Non Emergency Handover use Dynamic Priority ............................................... 14
4.2.8 Emergency Handover use Dynamic Priority ....................................................... 14
4.2.9 Filter Exceed Traffic threshold NCell .................................................................. 15
5 Related Counters and Alarms ........................................................................ 15
5.1 Related Counters ............................................................................................... 15
5.2 Related Alarms .................................................................................................. 15
6 Engineering Guide .......................................................................................... 16
6.1 Application Scenario .......................................................................................... 16
6.2 Configuration Description ................................................................................... 16
6.3 Feature Validation .............................................................................................. 24
6.3.1 Non Emergency handover Dynamic priority ....................................................... 24
6.3.2 Emergency handover Dynamic priority ............................................................... 25
6.3.3 Non Emergency handover filter high load NCell ................................................. 25
6.4 Feature Turn off ................................................................................................. 26
6.5 Network Impact .................................................................................................. 27
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7 Abbreviation .................................................................................................... 27
8 Reference Document ....................................................................................... 28
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FIGURES
Figure 6-1 Allow dynamic adjustment of handover priority .................................................17
Figure 6-2 Minimal resource threshold ...............................................................................18
Figure 6-3 Priority of handover ...........................................................................................19
Figure 6-4 Difference of dynamic priority ............................................................................20
Figure 6-5 Target cell traffic threshold ................................................................................21
Figure 6-6 Dynamic Priority NCell Traffic Threshold...........................................................22
Figure 6-7 Non Emergency Handover use Dynamic Priority ..............................................22
Figure 6-8 Emergency Handover use Dynamic Priority ......................................................23
Figure 6-9 Filter Exceed Traffic threshold NCell .................................................................23
Figure 6-10 Close the function of Allow dynamic adjustment of handover priority ..............27
TABLES
Table 4-1 Parameter List ...................................................................................................11
Table 4-2 Configuration rule of allow dynamic adjustment of handover priority ..................11
Table 4-3 Configuration rule of Minimal resource threshold ...............................................12
Table 4-4 Configuration rule of Priority of handover ...........................................................12
Table 4-5 Configuration rule of Difference of dynamic priority ............................................13
Table 4-6 Configuration rule of Target cell traffic threshold ................................................13
Table 4-7 Configuration rule of Dynamic Priority NCell Traffic Threshold ...........................14
Table 4-8 Non Emergency Handover use Dynamic Priority ................................................14
Table 4-9 Configuration rule of Emergency Handover use Dynamic Priority ......................14
Table 4-10 Filter Exceed Traffic threshold NCell ................................................................15
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1 Feature Attribute
BSC Version: [ZXG10 iBSC V6.30.103]
BTS Version: [Not related with BTS hardware platform]
Property: [Optional functionality]
Related Network Element:
NE Name Related or Not Special Requirements
MS -
BTS -
BSC √
MSC -
MGW -
SGSN -
GGSN -
HLR -
Dependent Function: [None]
Exclusive Function: [None]
Note: [None]
2 Overview
2.1 Feature Introduction
This feature enables the dynamic handover priority algorithm used in the target cells’
sequencing, controlling the handover direction and balancing the traffic between cells, so
as to reduce the interferences and improve voice quality as well.
This feature enables the dynamic priority algorithm for the target cells’ sequencing. The
user configures the different static priorities for different target cells according to the
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geographic position, the traffic and the handover successful ratio of the cell.
ZTE GSM supports dynamic handover priority algorithm, which is composed of the static
priority and the traffic of cell. The static priority of cell has 8 levels from 0 to 7. Bigger the
number, higher the priority. The traffic of cell is reflected by the resource percentage of
TCH, which refers to the percentage of idle TCH proportion in total TCH in the cell,
ranging from 0 to 100. Higher the resource percentage of TCH, fewer loads of the cell
bear. The dynamic priority is gained with the resource percentage of TCH and the static
priority. When the same static priorities are set for two cells, the cell with low traffic has
high dynamic priority. It means that it’s much easier to get channel resources and
successfully handover.
2.2 License Control
None license control for this feature in UR12 Release.
2.3 Correlation with Other Features
The queuing of the target cells is for either a Emergency handover or a non-Emergency
handover. This feature is associated with the handover algorithm.
Please refer to ZGB-02-02-001 Basic Handover Feature Guide for detail.
3 Technical Description
When more than one adjacent cell is available for a handover operation, those cells shall
be queued and handover attempts are made to those cells by the queuing order.
When the switch is open, the target cells are sorted and filtered first by the cell traffic.
Then they are queued by the dynamic priority and PBGT level. When the switch is close,
they are only queued by the static priority and PBGT level.
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Start
Is a Emergency handover?
Dynamic priority for
Emergency handover is
open?
Non Emergency handover
need to filter high load cell?
If the cell load of any cell in the
target cells list is bigger than the
filter thresholds, filter this cell
Dynamic priority for Non
Emergency handover is
open?
Y
N
Use the static priority for
target cell
Calculate the dynamic
priority for target cell
N
End
If the cell load of any cell in the
target cells list is 100, set the
priority of this cell to the lowest
Y
N
Cell Load bigger than the
Dynamic Priority NCell
Traffic Threshold?
Y Y
N
Y
N
3.1 Handover type classify
Handover Causes Type
Inter-cell handover is caused by high uplink BER. Emergency
Inter-cell handover is caused by high downlink BER. Emergency
Inter-cell handover is caused by low uplink level. Emergency
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Inter-cell handover is caused by low downlink level. Emergency
Handover is caused by the large distance between MS and the
network.
Emergency
Inter-cell handover caused by the fast uplink fading. Emergency
Adjacent handover is caused by the PBGT value. Non
Emergency
Handover between a macro-cell and a micro-cell. Non
Emergency
Directed retry Non
Emergency
Handover candidate enquiry Non
Emergency
Forced handover caused by a directed transfer. Non
Emergency
A handover is caused by seizure. Emergency
A traffic handover caused by the database. Non
Emergency
3.2 Traffic value for the target adjacent cells
1. For an adjacent cell configured in the same CMP board, check the current traffic in
the database.
2. For an adjacent cell configured in the different CMP board or inter BSC, the traffic
information is saved in the CellLoad fields as the adjacent cell object data table
The traffic information has a life circle. The traffic information might be inaccurate if
the last update is much earlier than this handover judgment.
3. For an external cell (a GSM external cell or a 3G external cell) BSC stores the traffic
value in an external cell in the CellLoad related field. This field is in the object data
table R_3GNCEL of a 3G adjacent cell. This traffic value also requires a life circle
attribute.
4. If the service cannot find the traffic values of theadjacent cell and the external
adjacent cell in database, it uses the default value (0) as the load values of these
cells.
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5. A parameter controls whether the traffic information of an external cell is extracted.
It is a BSC parameter.
3.3 Filter the high load target adjacent cells
The traffic queuing of the target adjacent cells is introduced below.
1. In an Emergency handover, the cells whose traffic is larger than the traffic threshold
are not filtered out. Then those cells not filtered out are queued by their traffic load.
The cells whose traffic load is 100 are put in the last place of target cell list. And the
cells whose traffic load less than 100 or equal to 100 are queued by their dynamic
priority and PBGT level respectively.
2. In a Non Emergency handover, if need to filter the high load cells, the cells whose
traffic is larger than the traffic threshold are filtered out. The cells remaining are
queued by their dynamic priority and PBGT level.
3. During the filtering, a cell’s traffic load is considered as 0 when the
non-local-module’s adjacent target cell traffic value in the database and the 3G
adjacent cell traffic value in the database are invalid.
3.4 Calculate the dynamic priority
Two algorithms are used to compute the handover priority. The static priority is effective
when the dynamic priority adjustment switch is not enabled or the neighbor cell load is
lower than the Dynamic Priority NCell Traffic Threshold. The static priority parameter
Hopriority is configured by OMCR. Its range is [0, 7] and the priority increases as the
value increases. The geological location of a cell is the major criterion in the static priority
configuration. An example is the microcells in a high building. The adjacent cells on the
same floor have higher priorities while the adjacent cells on different floors have lower
priorities. This is helpful to keep all the handovers on the same floor altitude and reduce
signal interference.
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When the dynamic priority adjusting function is enabled, the priority of a cell is computed
with consideration to its static priority Hopriority, the cell resource ratio RescIndTh, and
the idle channel ratio in the adjacent cell. The computing formula is given below.
In this formula, the DynPriority value is the minimal integral that satisfies the conditions.
SatPriority is the static priority of a cell. DynPriority is the dynamic priority of a cell. Per is
the idle channel ratio (percentage) in an adjacent cell. Res_Ths refers to
RESOURCETHS, the resource percentage of a cell.
The resource percentage of a cell refers to the percentage of the idle TCH in the total
TCH in the cell. Its valid value is larger than 10 and not larger than 100. This is because
MS cares only the TCH of the destination cell during a handover process. The traffic in
the cell decreases as the TCH resource percentage increases. A low percentage value
means the channel is easy to access and the handover is easier to succeed.
3.5 Adjacent cells queuing
The queuing rules for the adjacent cells are introduced below.
First, queue the target cells by the dynamic priority index.
Compare with the dynamic priority offset, DynPrioOffset. If two cells have a same
dynamic priority or the difference between their priorities is less than DynPrioOffset,
queue them by the power budget margin.
When queuing destination cells, DynPrioOffset is used to identify the cells within the
same range of the dynamic priorities. The cells within the same range of the dynamic
priorities are then queued according to their power budget margins.
The handover algorithm based on the dynamic priority has a dynamic advantage. When
the TCH resources are abundant, its priority is high, and it can accept more handover
services. When the TCH resources are consumed, its priority become lower, and it can
Res_Ths
500ln
Res_Ths
5perlnyStaPriorityDynPriorit
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accept less handover services. This is a control process based on negative feeding. It
can prevent unbalanced traffic sharing among cells.
4 Parameters and Configurations
4.1 Parameter List
Table 4-1 Parameter List
SN Name Figure
1 Allow dynamic adjustment of handover priority Figure 6-1
2 Minimal resource threshold Figure 6-2
3 Priority of handover Figure 6-3
4 Difference of dynamic priority Figure 6-4
5 Target cell traffic threshold Figure 6-5
6 Dynamic Priority NCell Traffic Threshold Figure 6-6
7 Non Emergency Handover use Dynamic Priority Figure 6-7
8 Emergency Handover use Dynamic Priority Figure 6-8
9 Filter Exceed Traffic threshold NCell Figure 6-9
4.2 Parameter Configuration
4.2.1 Allow dynamic adjustment of handover priority
Table 4-2 Configuration rule of allow dynamic adjustment of handover priority
Full name Allow dynamic adjustment of handover priority
Abbreviation hoControlPriChg
Description This parameter determines whether to allow dynamic adjustment
of handover priority.
Managed object Cell
Value range yes,no
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Unit NA
Default value no
4.2.2 Minimal resource threshold
Table 4-3 Configuration rule of Minimal resource threshold
Full name Minimal resource threshold
Abbreviation resourceThs
Description This parameter indicates the minimal resource threshold allowed
by the cell. It is used to calculate dynamic cell priority
Managed object Cell
Value range 0-100
Unit %
Default value 20
4.2.3 Priority of handover
Table 4-4 Configuration rule of Priority of handover
Full name Priority of handover
Abbreviation HoPriority
Description
According to GSM specifications, cell priority should be considered
in sequencing candidate cells. Therefore, there are three decisive
factors to sequence candidate cells: priority, traffic, and radio
communication environment. Priority and traffic have the most
impact on cell sequencing. If they lead to the same result,
sequence cells by radio conditions. The priority of a cell is higher if
this value is set higher.
Managed object Cell
Value range 0-7
Unit N/A
Default value 3
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4.2.4 Difference of dynamic priority
Table 4-5 Configuration rule of Difference of dynamic priority
Full name Difference of dynamic priority
Abbreviation dynPrioOffset
Description
This parameter defines a tolerable dynamic priority difference
between the destination cell and local cell during a handover when
using direction based handover algorithm. During handover, if the
first cells dynamic handover priority is higher than that of the
second cell but the second cell is in MS moving direction, then the
direction-based handover algorithm works if the difference
between the two cells’ handover priorities is within the tolerable
difference. MS is handover to the second cell.
Managed object Cell
Value range 1-7
Unit NA
Default value 1
4.2.5 Target cell traffic threshold
Table 4-6 Configuration rule of Target cell traffic threshold
Full name Target cell traffic threshold
Abbreviation TargetCellTrafficThs
Description
This parameter indicates the threshold for the target cell's traffic.
The system decides whether to perform handover to the cell
according to this parameter's value. If the traffic of the target cell is
higher than the threshold, handover is not made to the cell. This
parameter is used for 2G handover and reselecting adjacent cells.
Managed object Cell
Value range 0-100
Unit %
Default value 75
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4.2.6 Dynamic Priority NCell Traffic Threshold
Table 4-7 Configuration rule of Dynamic Priority NCell Traffic Threshold
Full name Dynamic Priority NCell Traffic Threshold
Abbreviation DynPrioNCellTrafThs
Description
If the neighbor cell load is bigger than this threshold, the dynamic
priority will be calculated; otherwise the static priority will be used
as the dynamic priority.
Managed object Cell
Value range 0-100
Unit
Default value 0
4.2.7 Non Emergency Handover use Dynamic Priority
Table 4-8 Non Emergency Handover use Dynamic Priority
Full name Non Emergency Handover use Dynamic Priority
Abbreviation NonEmergHoDynPrio
Description
When the cell parameter "hoControlPrioChg" is enabled, this
parameter determines whether to calculate the dynamic priority of
a neighbor cell in the case of non-emergency handover.
Managed object Cell
Value range 0:No 1:Yes
Unit
Default value 0
4.2.8 Emergency Handover use Dynamic Priority
Table 4-9 Configuration rule of Emergency Handover use Dynamic Priority
Full name Emergency Handover use Dynamic Priority
Abbreviation EmergHoDynPrio
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Description
When the cell parameter "hoControlPrioChg" is enabled, this
parameter determines whether to calculate the dynamic priority of
a neighbor cell in the case of emergency handover.
Managed object Cell
Value range 0:No 1:Yes
Unit
Default value 0
4.2.9 Filter Exceed Traffic threshold NCell
Table 4-10 Filter Exceed Traffic threshold NCell
Full name Filter Exceed Traffic threshold NCell
Abbreviation FiltExcdThsNCell
Description
In the case of non-emergency handover, "FiltExcdThsCell" is
supported to determine whether to filter the neighbor cells whose
traffic load exceeds the threshold. The switch does not depend on
the dynamic priority switch.
Managed object Cell
Value range 0:No 1:Yes
Unit
Default value 0
5 Related Counters and Alarms
5.1 Related Counters
There is no counter relative to this feature.
5.2 Related Alarms
This feature has no related alarms.
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6 Engineering Guide
6.1 Application Scenario
It is recommended to split the traffic in a busy cell. Determine the priority of an adjacent
cell according to its traffic condition and its relative location to the initial cell. Set the
priority of an adjacent cell to a high level if it is close to the initial cell and its traffic is idle.
If it is not, set it to a lower priority level.
This priority setting can push the traffic from a busy cell to an idle cell. If the traffic is busy
in a cell of high static priority, the dynamic priority of this cell will be adjusted to avoid
congestion in this cell.
6.2 Configuration Description
1. In the window of Resource Tree Configuration, double click [GSM logic functionality
configuration →cell functionality configuration →handover control], and select
handover resource cell to double click in the cell list on the right window. Then set
‘Allow dynamic adjustment of handover priority’ in the popped [handover control]
sheet as the figure below.
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Figure 6-1 Allow dynamic adjustment of handover priority
2. In the window of Resource Tree Configuration, double click [GSM logic functionality
configuration →cell functionality configuration →GSM cell configuration], and select
handover resource cell to double click in the cell list on the right window. Then set
‘Minimal resource threshold’ in the popped [GSM cell configuration] sheet as the
figure below.
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Figure 6-2 Minimal resource threshold
3. In the window of Resource Tree Configuration, double click [GSM logic functionality
configuration →cell functionality configuration →Adjacent cell configuration →GSM
Adjacent cell relation configuration], and select handover adjacent cell relation to
double click in the cell list on the right window. Then set ‘Priority of handover’ in the
popped [GSM adjacent cell relation configuration] sheet as the figure below.
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Figure 6-3 Priority of handover
4. In the window of Resource Tree Configuration, double click [GSM logic functionality
configuration →cell functionality configuration →handover control], and select
handover resource cell to double click in the cell list on the right window. Then set ‘A
Difference of dynamic priority’ in the popped [handover control] sheet as the figure
below.
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Figure 6-4 Difference of dynamic priority
5. In the window of Resource Tree Configuration, double click [GSM logic functionality
configuration →cell functionality configuration →Adjacent cell configuration →GSM
Adjacent cell relation configuration], and select handover adjacent cell relation to
double click in the cell list on the right window. Then set ‘Target cell traffic threshold’
in the popped [GSM adjacent cell relation configuration] sheet as the figure below.
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Figure 6-5 Target cell traffic threshold
6. In the window of Resource Tree Configuration, double click [GSM logic functionality
configuration →cell functionality configuration →GSM cell configuration], and select
handover resource cell to double click in the cell list on the right window. Then set
‘Dynamic Priority NCell Traffic Threshold’ in the popped [GSM cell configuration]
sheet as the figure below.
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Figure 6-6 Dynamic Priority NCell Traffic Threshold
7. In the window of Resource Tree Configuration, double click [GSM logic functionality
configuration →cell functionality configuration →GSM cell configuration], and select
handover resource cell to double click in the cell list on the right window. Then set
‘Non Emergency Handover use Dynamic Priority’ in the popped [GSM cell
configuration] sheet as the figure below.
Figure 6-7 Non Emergency Handover use Dynamic Priority
8. In the window of Resource Tree Configuration, double click [GSM logic functionality
configuration →cell functionality configuration →GSM cell configuration], and select
handover resource cell to double click in the cell list on the right window. Then set
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‘Emergency Handover use Dynamic Priority’ in the popped [GSM cell configuration]
sheet as the figure below.
Figure 6-8 Emergency Handover use Dynamic Priority
9. In the window of Resource Tree Configuration, double click [GSM logic functionality
configuration →cell functionality configuration →GSM cell configuration], and select
handover resource cell to double click in the cell list on the right window. Then set
‘Filter Exceed Traffic threshold NCell’ in the popped [GSM cell configuration] sheet
as the figure below.
Figure 6-9 Filter Exceed Traffic threshold NCell
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6.3 Feature Validation
6.3.1 Non Emergency handover Dynamic priority
Test Item Non Emergency handover Dynamic handover priority
Precondition 1. check CN is healthy;
2. check BSC is healthy;
3. check SDR is healthy;
4. check default cell configuration and parameters in
BSC;
5. MSs are ready;
6. ensure good radio environment;
Test Steps 1. Configure cell B and cell C as “Adjacent handover and
reselect cell” for Cell A.
2. Priority of cell B is higher than that of cell C. (for
example: Cell B’s priority is 7 and cell C’s priority is 5)
3. Set “Minimal resource threshold” of serving cell as
“15”.
4. Set ” Allow dynamic adjustment of handover priority”
as ’Yes’ in handover control;
5. Set “Non Emergency Handover use Dynamic Priority”
as ‘Yes’;
6. Rx_level of cell B > Rx_level of cell C > Rx_level of cell
A
7. Set “Difference of dynamic priority” as default value 0
8. MS make a call occupied in cell A
9. Move MS far away from cell A until Non Emergency
handover.
10. Make some calls in cell B to make idle channel
percentage is not more than ’ TargetCellTrafficThs’;
11. Repeat step 8-10.
Anticipative Result 1. In step 9, MS handover successfully , and target cell is
cell B after evaluate the dynamic priority of all target
cells
2. In step 11, MS handover successfully , and target cell
is cell C due to evaluate the dynamic priority of all
target cells
Test Result Non Emergency handover Dynamic priority is effective
Parameters Setting Default parameters
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6.3.2 Emergency handover Dynamic priority
Test Item Emergency handover Dynamic priority
Precondition 1. check CN is healthy;
2. check BSC is healthy;
3. check SDR is healthy;
4. check default cell configuration and parameters in
BSC;
5. MSs are ready;
6. ensure good radio environment;
Test Steps 1. Configure cell B and cell C as “Adjacent handover and
reselect cell” for Cell A.
2. Priority of cell B is higher than that of cell C. (for
example: Cell B’s priority is 7 and cell C’s priority is 5)
3. Set “Minimal resource threshold” of serving cell as
“15”.
4. Set ” Allow dynamic adjustment of handover priority”
as ’Yes’ in handover control;
5. Set “Emergency Handover use Dynamic Priority” as
‘Yes’;
6. Rx_level of cell B > Rx_level of cell C > Rx_level of cell
A
7. Set “Difference of dynamic priority” as default value 0
8. MS make a call occupied in cell A
9. Move MS far away from cell A until emergency
handover.
10. Make some calls in cell B to make idle channel
percentage is not more than ’TargetCellTrafficThs’;
11. Repeat step 8-10.
Anticipative Result 1. In step 9, MS handover successfully , and target cell is
cell B after evaluate the dynamic priority of all target
cells
2. In step 11, MS handover successfully , and target cell
is cell C due to evaluate the dynamic priority of all
target cells
Test Result Emergency handover Dynamic priority is effective
Parameters Setting Default parameters
6.3.3 Non Emergency handover filter high load NCell
Test Item Non Emergency handover filter high load NCell
Precondition 1. check CN is healthy;
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2. check BSC is healthy;
3. check SDR is healthy;
4. check default cell configuration and parameters in
BSC;
5. MSs are ready;
6. ensure good radio environment;
Test Steps 1. Configure cell B and cell C as “Adjacent handover and
reselect cell” for Cell A.
2. Priority of cell B is same as cell C. (for example: Cell
B’s priority is 5 and cell C’s priority is 5)
3. Set “Filter Exceed Traffic threshold NCell” as ‘Yes’;
4. Rx_level of cell B > Rx_level of cell C > Rx_level of cell
A
5. MS make a call occupied in cell A
6. Move MS far away from cell A until handover.
7. Make some calls in cell B to make idle channel
percentage is no more than ’ TargetCellTrafficThs’ but
bigger than ‘FiltExcdThsNCell’;
8. Repeat step 6-7.
Anticipative Result 1. In step 6, MS handover successfully, and target cell is
cell B.
2. In step 7, MS handover successfully, and target cell is
cell C due to cell B is filtered.
Test Result Non Emergency handover filter high load NCell
Parameters Setting Default parameters
6.4 Feature Turn off
In the window of Resource Tree Configuration, double click [GSM logic functionality
configuration →cell functionality configuration →handover control], and select handover
resource cell to double click in the cell list on the right window. Then set ‘Allow dynamic
adjustment of handover priority’ as “No”.
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Figure 6-10 Close the function of Allow dynamic adjustment of handover priority
6.5 Network Impact
Dynamic priority can adjust cell traffic load flexibly. If the cell static priority is high, the
priority will be lower with the traffic load increase. It is avoided that all the handover are to
the cell with high static priority so as to make heavy traffic. After using dynamic priority,
priority can be adjusted according to traffic. When traffic is heavy, the priority becomes
low. This feature can realize traffic balance.
In addition, the target adjacent cell which has the highest level may not be selected as
the final target cell due to the high load, so this feature may influence the Handover
Success Rate.
7 Abbreviation Abbreviations Full Characteristics
3GPP 3rd
Generation Partnership Project
BER Bit Error Rate
BSC Base Station Controller
BTS Base Transceiver Station
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GGSN Gateway GPRS Support Node
GSM Global System for Mobile Communications
HLR Home Location Register
MGW Media GateWay
MS Mobile Station
MSC Mobile Service Switching Centre
SGSN Serving GPRS SUPPORT NODE
TCH Traffic Channel
8 Reference Document
ZXG10 iBSC (V6.30.10) Base Station Controller Radio Parameter Reference