Thursday, 25 August 2016

Adaptive inter-cell interference coordination (ICIC)

 Overview

ICIC works with scheduling and power control to mitigate inter-cell interference. ICIC divides the frequency band of a cell into center and edge bands and classifies users into cell center users (CCUs) and cell edge users (CEUs). With ICIC, the eNodeB schedules CCUs and CEUs on different cell bands and allocates different power to CCUs and CEUs.
Huawei eNodeBs support static and adaptive ICIC. Adaptive ICIC differs from static ICIC in the following ways:
  • Static ICIC requires manual configuration of ICIC switches and edge band modes. This configuration method cannot adapt to changes in UE type (CCU or CEU) distribution and cell load.
  • Adaptive ICIC determines whether to enable ICIC in an area based on inter-cell interference and cell load. In addition, adaptive ICIC automatically configures edge band modes and optimizes ICIC working modes and edge band modes based on load changes.
This document describes only adaptive ICIC, which corresponds to the optional feature TDLOFD-060201 Adaptive Inter-Cell Interference Coordination.
Huawei ECO6910, whose network element (NE) type is eCoordinator, serves as a coordinator on a radio network and provides a platform for implementing adaptive ICIC.
With adaptive ICIC, eNodeBs independently report cell information to the ECO6910, and then the ECO6910 uses the reported information to configure and optimize ICIC working modes and edge band modes. Adaptive ICIC is activated or deactivated on the M2000 and implemented jointly by the M2000, ECO6910, and eNodeBs.
Figure 2-1 shows the network architecture for adaptive ICIC.
Figure 2-1 Network architecture for adaptive ICIC
  • The blue, purple, and yellow areas indicate different cells under the same eNodeB.
  • The black lines illustrate the connections between the eNodeBs and the M2000 before adaptive ICIC is enabled.
  • The red lines illustrate the connections between the ECO6910 and the eNodeBs and M2000 after adaptive ICIC is enabled.
When the ECO6910 is used to implement adaptive ICIC, the ECO6910, eNodeBs, and M2000 must be connected as illustrated by the black and red lines in Figure 2-1.
Table 2-1 describes the functions of NEs involved in adaptive ICIC.
Table 2-1 Functions of NEs involved in adaptive ICIC
NE
Function
UE
  • Measures the reference signal received power (RSRP) of the serving cell and neighboring cells.
  • Reports the measurement results to the eNodeB.
eNodeB
  • Reports cell information (including inter-cell interference data and cell edge load data) to the ECO6910.
  • Updates the ICIC working modes and edge band modes for cells based on the configurations delivered by the ECO6910.
ECO6910
  • Maintains network-level interference data and cell edge load data.
  • Implements the adaptive ICIC algorithm by configuring ICIC working modes and edge band modes based on cell information reported by eNodeBs.
  • Delivers the configurations to eNodeBs.
M2000
  • Serves as a platform for enabling and disabling adaptive ICIC.
  • Displays the status of adaptive ICIC.
  • Displays and delivers the optimization advice on ICIC working modes and edge band modes.
LMT
  • Serves as a supplementary platform for enabling and disabling adaptive ICIC.
  • Displays the status of adaptive ICIC.

3 Technical Description

3.1 Concepts

3.1.1 CCU and CEU

Similar to static ICIC, adaptive ICIC also classifies users into CCUs and CEUs. For details about how to identify CCUs and CEUs, see ICIC Feature Parameter Description.
CCUs and CEUs are scheduled as follows:
  • Band allocation
    • eNodeBs preferentially schedule CCUs on the center band. If there are remaining frequency resources on the center band, eNodeBs can also schedule CEUs on the center band.
    • eNodeBs preferentially schedule CEUs on the edge band. If there are remaining frequency resources on the edge band and CCUs have a higher scheduling priority on the edge band than CEUs, eNodeBs can also schedule CCUs on the edge band.
  • Power allocation
    eNodeBs allocate higher power to CEUs and lower power to CCUs.

3.1.2 ICIC Working Mode

Adaptive ICIC works in three modes: Reuse1, Reuse3, and Reuse6. The division of a cell band into center and edge bands varies according to the ICIC working mode.

Reuse1

In Reuse1 mode, the cell band is not divided into center and edge bands. UEs are not classified into CCUs or CEUs. All UEs share the entire cell band. In the downlink, all UEs use the same power to receive signals. In the uplink, the transmit power of each UE is determined by the uplink power control algorithm. For details about power control, see Power Control Feature Parameter Description.
All cells initially work in Reuse1 mode. Some cells can work only in Reuse1 mode when meeting all the following conditions:
  • These cells have the same bandwidth but different frequencies or have the same frequency but different bandwidths.
  • The bandwidths of these cells are 1.4 MHz or 3 MHz.

Reuse3

In Reuse3 mode, 1/3 of the cell band is configured as the edge band, and the remaining 2/3 of the cell band is configured as the center band. Figure 3-1 shows the Reuse3 mode.
Figure 3-1 Reuse3 mode
As shown in Figure 3-1, there are three edge band modes in Reuse3 mode: Pattern3-1, Pattern3-2, and Pattern3-3. The three modes correspond to low, medium, and high sub-bands, respectively. In each mode, the edge band occupies 1/3 of the cell band. For example, if a cell uses Pattern3-1, the lowest 1/3 of the cell band works as the edge band. Some cells cannot work in Reuse3 mode when meeting all the following conditions:
  • These cells have the same bandwidth but different frequencies or have the same frequency but different bandwidths.
  • The bandwidths of these cells are 1.4 MHz or 3 MHz.

Reuse6

In Reuse6 mode, 1/6 of the cell band is configured as the edge band, and the remaining 5/6 of the cell band is configured as the center band. Figure 3-2 shows the Reuse6 mode.
Figure 3-2 Reuse6 mode
As shown in Figure 3-2, there are six edge band modes (Pattern6-1 to Pattern6-6) in Reuse6 mode. The six modes correspond to six sub-bands in ascending order of frequency. In each mode, the edge band occupies 1/6 of the cell band. For example, if a cell uses Pattern6-6, the highest 1/6 of the cell band works as the edge band.
LTE systems use single carrier frequency division multiple access (SC-FDMA) in the uplink. Therefore, UEs can work only on continuous uplink bands. To prevent the uplink band from being too fragmented, a cell cannot use the Reuse6 mode in the uplink. In addition, to ensure sufficient downlink bandwidth, cells with a bandwidth of 1.4 MHz, 3 MHz, or 5 MHz cannot work in Reuse6 mode in the downlink.

3.2 Principles

After adaptive ICIC is activated, the ECO6910 configures and optimizes the ICIC working modes and edge band modes based on inter-cell interference and cell load. Figure 3-3 shows the working principles of adaptive ICIC.
Figure 3-3 Working principles of adaptive ICIC

3.2.1 Starting an Optimization Task

You can select all or some cells under the ECO6910 or under a specified eNodeB as the area for which adaptive ICIC is to be activated, and specify the OptiType parameter to determine whether adaptive ICIC takes effect in uplink, downlink, or both.
Adaptive ICIC can be activated and deactivated using the M2000 or MML commands on the ECO6910 LMT. After adaptive ICIC is activated, the ECO6910 identifies areas with high interference and heavy load based on cell load and inter-cell interference. Based on the identification results, the ECO6910 configures and optimizes the ICIC working modes and edge band modes.

3.2.2 Identifying Areas with High Interference and Heavy Load

The ECO6910 identifies areas with high interference and heavy load based on cell load and inter-cell interference in each optimization period. Based on the identification results, the ECO6910 configures and optimizes the ICIC working modes and edge band modes.

Areas with High Interference

The RSRP of the serving cell and the RSRP of the neighboring cells are used to determine whether an area has high interference. The procedure for identifying areas with high interference is as follows:
  1. UEs send ICIC event A3/A6 measurement reports to the eNodeBs. Each report includes the RSRP values of a UE's serving cell and neighboring cells. For details about events A3 and A6, see ICIC Feature Parameter Description.
  2. The eNodeBs calculate unidirectional interference weights based on the reported RSRP values, record them in cell-level intra-frequency neighboring relation tables (NRTs), and periodically report the NRTs to the ECO6910.
    NOTE:
    A unidirectional interference weight is the weight of the interference generated from one cell to another cell.
  3. The ECO6910 generates a network-level NRT based on the cell-level intra-frequency NRTs, calculates bidirectional interference weights based on unidirectional interference weights, and identifies areas with high interference.

Areas with Heavy Load

The eNodeBs report cell load information to the ECO6910. The cell load information includes the average physical resource block (PRB) usage and the average number of scheduled UEs. The ECO6910 identifies areas with heavy load based on the cell load information. If the ratio of the number of heavily loaded cells to the total number of cells in an area with high interference has reached a certain value, the ECO6910 regards this area as heavily loaded. Otherwise, the ECO6910 regards this area as lightly loaded.

3.2.3 Configuring and Optimizing ICIC Working Modes and Edge Band Modes

Self-Configuration

The ECO6910 periodically evaluates cell load and inter-cell interference, based on which it configures the ICIC working modes and edge band modes.
  • For cells in an area with high interference and heavy load, the ECO6910 sets the ICIC working mode to Reuse3 and configures the edge band mode for each cell. If two cells have the same edge band mode, the ECO6910 checks whether the bidirectional interference weights have reached a specific threshold.
    • If so, the ECO6910 changes the ICIC working modes of the two cells to Reuse6 and configures different edge band modes for the two cells.
    • If not, the ICIC working modes and edge band modes of the two cells remain unchanged.
  • For cells in an area with high interference and light load, the ECO6910 sets the ICIC working mode to Reuse1.
  • For cells in an area without high interference, the ECO6910 also sets the ICIC working mode to Reuse1.

Self-Optimization

Inter-cell interference changes with cell load and UE type distribution. Therefore, adaptive ICIC periodically optimizes the ICIC working modes and edge band modes. After the ICIC working mode is determined in an optimization period, the ECO6910 checks the eNodeB-reported average number of PRBs used for CEUs. Based on this information, the ECO6910 determines whether to reconfigure the edge band mode for cells in Reuse3 and Reuse6 modes every 5 seconds.
  • If the average number of PRBs used for CEUs in a cell is less than 1/6 of the entire cell band, the ECO6910 sets the ICIC working mode of the cell to Reuse6 and the cell shrinks its edge band.
  • If the average number of PRBs used for CEUs in a cell is greater than 1/3 of the entire cell band, the cell's neighboring cells shrink their edge bands and the cell expands its edge band on the shrunk edge bands. If the edge bands of neighboring cells are not actually shrunk, the cell has a fixed edge band that is 1/3 of the entire cell band.
  • If the average number of PRBs used for CEUs is greater than 1/6 and less than 1/3 of the entire cell band, the ICIC working mode and edge band mode of the cell remain unchanged.

4 Related Features

Prerequisite Features

Adaptive ICIC requires the following features related to scheduling or power control:
  • TDLBFD-002025 Basic Scheduling
  • TDLOFD-001015 Enhanced Scheduling
  • TDLOFD-00101502 Dynamic Scheduling
  • TDLBFD-002026 Uplink Power Control
  • TDLBFD-002016 Dynamic Downlink Power Allocation
With features related to scheduling, eNodeBs schedule the CEUs in a cell on the edge band of this cell, and therefore mitigate inter-cell interference in the frequency domain. With features related to power control, eNodeBs allocate appropriate power resources to CCUs and CEUs, further reducing inter-cell interference.

Mutually Exclusive Features

Adaptive ICIC cannot be used with the following static ICIC features:
  • TDLBFD-00202201 Downlink Static Inter-Cell Interference Coordination
  • TDLBFD-00202202 Uplink Static Inter-Cell Interference Coordination
  • TDLOFD-002008 Adaptive SFN/SDMA
  • TDLOFD-001082 Inter-BBU Adaptive SFN/SDMA
It is recommended that adaptive ICIC not be used together with static ICIC because of the following reasons:
  • If static ICIC is enabled on a network where adaptive ICIC has been enabled, static ICIC will not work.
  • If adaptive ICIC is enabled on a network where static ICIC has been enabled, static ICIC will be automatically disabled. When the ECO6910 collects network information and determines whether ICIC takes effect, the ICIC working mode of the cell is changed to Reuse1. Consequently, the band on which UEs are scheduled and the power allocated to UEs vary, which causes UE throughput fluctuation and deteriorates user experience. If UE throughput is too low during handovers or radio bearer setup, the handover success rate may decrease and the service drop rate may increase.

Impacted Features

Adaptive ICIC impacts scheduling and power control as follows:
  • Adaptive ICIC affects scheduling in both the uplink and downlink in the following ways:
    • Adaptive ICIC provides edge band modes and UE types (CCU or CEU) for scheduling.
    • With adaptive ICIC, eNodeBs schedule the CEUs of a cell on the edge band and schedule CCUs preferentially on the center band. The eNodeBs can also schedule CCUs on the entire cell band.
  • Adaptive ICIC provides UE type information for downlink power control.
    Downlink power control allocates appropriate power resources to CCUs and CEUs based on the UE types and the PA values configured for CCUs and CEUs. In Reuse1 mode, all UEs use the same PA value. For details about the description and configuration of PA, see Power Control Feature Parameter Description.

5 Network Impact

System Capacity

Adaptive ICIC increases the throughput of CEUs by reducing inter-cell inter-CEU interference.
Adaptive ICIC reduces the system capacity because the downlink transmit power of CCUs is reduced. The decrease in system capacity depends on the UE type distribution in the cell. Generally, the system capacity does not decrease by more than 5%.

Network Performance

Adaptive ICIC enhances network coverage by increasing the throughput of CEUs.
Adaptive ICIC increases the number of signaling messages over the air interface because:
  • Adaptive ICIC requires that UEs detect and report the RSRP values of neighboring cells in the event A3 or A6 measurement report for the eNodeB to distinguish between CEUs and CCUs in a cell.
  • The eNodeB sends UEs the RRC Connection Reconfiguration message, which contains the setting of UE transmit power.

6 Engineering Guidelines

6.1 When to Use Adaptive ICIC

It is good practice to activate adaptive ICIC when the intra-frequency cells on an LTE network experience intra-frequency interference. Adaptive ICIC does not affect ongoing services and therefore can be activated any time.
Once adaptive ICIC has been activated, the ECO6910 will configure and optimize the ICIC working modes and edge band modes for cells in an area with high interference and heavy load when the interference and cell load reach their respective thresholds.
Adaptive ICIC takes priority over static ICIC. If adaptive ICIC is activated, static ICIC on the eNodeB will not work, and the related operations (such as the switch and mode configurations) no longer take effect. Static ICIC can be enabled on the eNodeB only when adaptive ICIC is deactivated.
Adaptive ICIC takes effect on a per cell basis and applies to multi-operator core network (MOCN) and RAN sharing scenarios.

6.2 Required Information

Before activating adaptive ICIC on an LTE network, collect the key performance indicators (KPIs) of the LTE network.
The following eNodeB counters are involved in adaptive ICIC:
  1. Counters related to network load: average number of downlink CEUs in a cell, average number of uplink CEUs in a cell, average number of used uplink PRBs, and average number of used downlink PRBs
  2. Counters related to interference: number of times MCS index n is scheduled on the PDSCH (where n ranges from 0 to 31), number of times MCS index n is scheduled on the PUSCH (where n ranges from 0 to 31), and number of reports with a wideband CQI of n (where n ranges from 0 to 15)
For the IDs and descriptions of these counters, see 8 Counters.

6.3 Planning

RF Planning

None

Network Planning

The neighboring cells in an optimization zone must use the same frequency and bandwidth and the cell bandwidth in an optimization zone must be greater than or equal to 5 MHz. If the neighboring cells use different frequencies or bandwidths, adaptive ICIC does not take effect on the neighboring cells and the neighboring cells only work in Reuse1 mode.

Hardware Planning

The ECO6910 and M2000 must be deployed.

6.4 Deployment

6.4.1 Process

Figure 6-1 outlines the procedure for deploying adaptive ICIC.
Figure 6-1 Procedure for deploying adaptive ICIC

6.4.2 Requirements

Hardware

  • eNodeBs are available. Adaptive ICIC applies only to macro cells in eRAN6.0 or later, including:
    • LTE macro cells served by single-mode base stations, which are DBS3900 LTE, BTS3900 LTE, BTS3900A LTE, BTS3900L LTE, and BTS3900AL LTE.
    • LTE macro cells served by multi-mode base stations, which are DBS3900, BTS3900, BTS3900A, BTS3900L, and BTS3900AL.
  • The ECO6910 has been installed, initially configured, and commissioned. The ECO6910 is available and connected to eNodeBs.
NOTE:
For details about how to install, initially configure, and commission the ECO6910, see ECO6910 Installation Guide, ECO6910 Initial Configuration Guide, and ECO6910 Commissioning Guide, respectively.

System Configurations

Intra-frequency neighbor relationships are configured between the cells in an optimization zone.

License

Operators have purchased and activated the following licenses on the ECO6910:
  • ECO6910 Basic Software-LTE TDD (cell)
  • Adaptive Inter-Cell Interference Coordination-LTE TDD (cell)
Adaptive Inter-Cell Interference Coordination-LTE TDD (cell) limits the total number of cells that can be optimized by adaptive ICIC. If the number of selected cells exceeds the licensed limit, the ECO6910 reports ALM-51301 Number of Resources Used Exceeding Alarm Threshold Specified by License.

6.4.3 Data Preparation

This section describes the data that you need to collect for setting parameters. Required data is data that you must collect for all scenarios. Collect scenario-specific data when necessary for a specific feature deployment scenario.
There are three types of data sources:
  • Network plan (negotiation not required): Parameters are planned and set by operators.
  • Network plan (negotiation required): Parameters are planned by operators and negotiated with the EPC or peer transmission equipment.
  • User-defined: Parameters are set as required by users.

Required Data

None

Scenario-specific Data

When configuring adaptive ICIC, set the following parameters:
  • Parameters for an optimization zone and optimization objects. For details, see Table 6-1.
  • Parameters for adaptive ICIC. For details, see Table 6-2.
  • Parameters for an optimization task. For details, see Table 6-3.
    Table 6-1 Parameters for an optimization zone and optimization objects
    Parameter Name
    Parameter ID
    Setting Notes
    Data Source
    Optimization Zone ID
    OptiZoneId
    This parameter uniquely identifies an optimization zone on the eCoordinator.
    User-defined
    Optimization Zone Name
    OptiZoneName
    This parameter specifies the optimization zone name.
    User-defined
    Optimization Object Type
    OptiObjType
    This parameter specifies the type of optimization objects.
    When this parameter is set to ECO(ECO), the optimization objects are all cells managed by the eCoordinator.
    When this parameter is set to NE(NE), the optimization objects are all cells under the corresponding eNodeB.
    When this parameter is set to CELL(CELL), the optimization object is a specified cell.
    Network plan (negotiation not required)
    Optimization Object ID
    OptiObjId
    This parameter uniquely identifies an optimization object.
    When Optimization Object Type is set to NE(NE), set this parameter to NeIndex so that you can run the LST NE command to query the indexes of all NEs managed by the eCoordinator.
    When Optimization Object Type is set to CELL(CELL), set this parameter to CellIndex so that you can run the LST LTECELL command to query the indexes of all LTE cells managed by the eCoordinator.
    Network plan (negotiation not required)
    Optimization Object RAT
    RAT
    This parameter indicates the RAT used in a cell to be optimized. This parameter is available only when Optimization Object Type is set to CELL(CELL). Set this parameter to LTE.
    Network plan (negotiation not required)
Table 6-2 Parameters for adaptive ICIC
Parameter Name
Parameter ID
Setting Notes
Data Source
Optimization Type
OptiType
You are advised to set this parameter to DL(DownLink) so that cell edge bands are optimized only in the downlink, because traffic is heavy in the downlink and light in the uplink.
Network plan (negotiation not required)
Optimization Period
OptiPeriod
This parameter specifies the optimization period for adaptive ICIC. The system implements optimization each time the optimization period arrives.
Set this parameter to Day_1(1 Day) or longer if more than 2000 cells are to be optimized. Set this parameter to Hour_1(1 Hour) or longer if 100 to 2000 cells are to be optimized. Set this parameter to Min_15(15 Minutes) if 20 to 99 cells are to be optimized. Set this parameter to Min_3(3 Minutes) if less than 20 cells are to be optimized. This shortens the duration from the time when adaptive ICIC is started to the time when the ECO6910 generates optimization advice.
Network plan (negotiation not required)
Table 6-3 Parameters for an optimization task
Parameter Name
Parameter ID
GUI Parameter Name on the M2000
Setting Notes
Data Source
Optimization Feature Index
OptiFeatureId
Feature ID
This parameter uniquely specifies the ID of an optimization task on the eCoordinator.
User-defined
Optimization Feature Name
OptiName
Service Name
This parameter specifies the type of an optimization task.
User-defined
Feature Type
FeatureType
Service Type
This parameter specifies the type of an optimization task. If MML commands are used, set this parameter to AICIC(AICIC). If the M2000 is used, select LTE Adaptive ICIC.
Network plan (negotiation not required)
Optimize Cell Type
OptiCellType
Cell Type
This parameter specifies the type of a cell to be optimized.
  • To optimize only FDD cells, set this parameter to FDD.
  • To optimize only TDD cells, set this parameter to TDD.
  • To optimize both FDD and TDD cells, set this parameter to BOTH in the related MML commands or select Both on the M2000.
Network plan (negotiation not required)
Optimization Parameter Template ID
ParaId
Parameter Policy
This parameter uniquely specifies the ID of an optimization parameter template. The optimization parameter template is added by running the ADD AICICOPTIPARA command.
Network plan (negotiation not required)
Optimization Zone ID
OptiZoneId
Optimization Zone
This parameter uniquely specifies the ID of an optimization zone. The optimization zone is added by running the ADD OPTIZONE command.
Network plan (negotiation not required)
Feature Switch
EnableSwitch
Start Optimization Service
This parameter specifies whether to enable an optimization task.
  • To activate adaptive ICIC, set this parameter to ON.
  • To deactivate adaptive ICIC, set this parameter to OFF.
Network plan (negotiation not required)
Optimization Implementation Mode
ImplementMode
Execution Mode
This parameter specifies the mode for implementing the optimization advice.
  • When this parameter is set to MANUAL, the optimization advice is implemented only after you have confirmed it.
  • When this parameter is set to NOW, the optimization advice is implemented immediately after it is generated.
  • When this parameter is set to TIMER, the optimization advice is automatically implemented at the scheduled time.
The ECO6910 generates optimization advice on reconfiguration of adaptive ICIC working mode based on cell load and inter-cell interference in an optimization period. If optimization advice is not delivered to eNodeBs in time, the reconfigured ICIC working mode will not adapt to cell load and inter-cell interference in an optimization period, weakening the optimization effect of adaptive ICIC. The value NOW is recommended because the ICIC working mode can adapt quickly to cell load and inter-cell interference.
If OptiPeriod is set to Min_3(3 Minutes), the optimization advice will be frequently updated on the M2000, which makes it difficult to manually deliver the optimization advice. To address this issue, set Optimization Implementation Mode to NOW.
Network plan (negotiation not required)
Optimization Delivery Time
ImplementSchedule
Schedule Time
This parameter indicates the time that the optimization advice is scheduled for delivery. This parameter is valid when Optimization Implementation Mode is set to TIMER. The generated optimization advice is delivered only at the scheduled time.
Network plan (negotiation not required)

6.4.5 Initial Configuration

Adaptive ICIC can be initially configured using the M2000 or using MML commands on the ECO6910 LMT. The M2000 is recommended because the NEs to be managed by the ECO6910 can be added only on the M2000 client.

Using the M2000

Before initially configuring adaptive ICIC, upload the ECO6910 mediation software to the M2000 server. To initially configure adaptive ICIC on the M2000 client, perform the following operations:
  1. Select NEs to be managed by the ECO6910.
    1. Log in to the M2000 client. Choose Configuration > eCoordinator Settings in the traditional style, or double-click Configuration on the Application Center tab page and then choose Settings > eCoordinator Settings in the application style.
      The eCoordinator Settings window is displayed.
    2. Click the NE Settings tab page in the eCoordinator Settings window. Choose the target eCoordinator in the navigation tree and click , or right-click the eCoordinator and choose Modify from the shortcut menu.
      The Setting dialog box is displayed, as shown in Figure 6-2.
      Figure 6-2 Setting dialog box
    3. Under Available NEs, select the NEs to be managed by the ECO6910 and add them to Selected NEs. Click Next.
    4. Specify User Name and Password, and then click OK.
    5. Click to update the list of NEs to be managed by the ECO6910.
  2. Specify the zone to be optimized by the ECO6910.
    1. Click the Zone Settings tab page in the eCoordinator Settings window. Click .
      The Add Zone dialog box is displayed, as shown in Figure 6-3.
      Figure 6-3 Add Zone dialog box
      NOTE:
      Cells under a newly added NE will be displayed under Available Objects 10 minutes after the NE is added.
    2. In the Add Zone dialog box, specify Zone Name. Select the optimization objects under Available Objects, add them to Selected Objects, and click OK.
    3. Click to update the optimization zones.
  3. Set the optimization parameters.
    1. On the M2000 client, choose SON > LTE Adaptive ICIC in the traditional style, or double-click SON on the Application Center tab page and then choose Self Optimization > LTE Adaptive ICIC in the application style.
      The LTE Adaptive ICIC window is displayed.
    2. On the Parameter Policy tab page, select the target eCoordinator and click to create optimization parameters. Set the parameters and then click Save. For details about the parameters, see Table 6-2.
  4. Create an optimization task.
    • Click the Optimization Management tab page in the LTE Adaptive ICIC window. Click to create an optimization task.
      The Create Optimization Service dialog box is displayed.
    • Set the parameters and click OK in the Create Optimization Service dialog box. For parameter details, see Table 6-3.

Using MML Commands

To initially configure adaptive ICIC using MML commands, add NEs to be managed by the ECO6910 on the M2000 client and then log in to the ECO6910 LMT to perform the following operations:
NOTE:
For details about how to add NEs to be managed by the ECO6910 on the M2000 client, see 1 in Using the M2000.
  1. Run the ADD OPTIZONE command to add an optimization zone. For details about how to set the related parameters, see Table 6-1.
  2. Run the ADD OPTIOBJ command to add an optimization object. For details about how to set the related parameters, see Table 6-1.
  3. Run the ADD AICICOPTIPARA command to add optimization parameters for adaptive ICIC. For details about how to set the related parameters, see Table 6-2.
  4. Run the ADD OPTIFEATURE command to add an optimization task. For details about how to set the related parameters, see Table 6-3.

6.4.6 Activation Observation

Using the M2000

To check the running status of adaptive ICIC on the M2000, use either of the following methods:
  • Checking the value of Status
    On the Optimization Management tab page, select an optimization task and click . Check the value of Status in the displayed Query Optimization Service dialog box.
    • If Running is displayed under Status, as shown in Figure 6-4, the optimization task is running properly. When the optimization task is complete, Completed is displayed under Status. The system displays the optimization advice on the Optimization Advice tab page in the right pane of the Optimization Management tab page.
    • If Exception is displayed under Status, the task failed. Rectify the fault by following the procedures for handling ALM-51304 Task Running Abnormal in ECO6910 Alarm Reference.
    • If Stopped is displayed under Status, the task has been stopped. Click to restart the task.
      Figure 6-4 Query Optimization Service dialog box
  • Checking the SON logs
    The M2000 logs the optimization tasks related to adaptive ICIC. To check the logs for the task status, perform the following operations:
    1. On the M2000 client, choose SON > SON Log.
      The SON Log window is displayed.
    2. Click the Query SON Log tab page. On the Query SON Log tab page, set Log Category to Adaptive ICIC Log, set Event Name to Not Limited, and set Event Source Object and Time Period as required.
    3. Click Synchronize in the lower right corner of the SON Log window.
    4. Click Query.

Using MML Commands

Run the DSP OPTIFEATURE command and check the value of State in the command output:
  • If the value is Running, the optimization task is running properly.
  • If the value is Abnormal, rectify the fault by following the procedures for handling ALM-51304 Task Running Abnormal in ECO6910 Alarm Reference.
  • If the value is Stopped, the optimization task has been stopped. To restart the optimization task, run the MOD OPTIFEATURE command with Feature Switch set to ON(ON).

6.4.7 Optimization Advice Confirmation and Delivery

If the Optimization Implementation Mode parameter is set to MANUAL(MANUAL), the generated optimization advice must be confirmed by the operator before it can be delivered to eNodeBs. The latest batch of optimization advice is recommended and all of the optimization advice in the same batch must be delivered together.
NOTE:
  • If the delivered optimization advice is not the latest, the reconfigured ICIC working mode will not adapt to cell load and inter-cell interference, therefore adversely affecting the network performance.
  • The M2000 delivers all of the optimization advice in the same batch to eNodeBs, even if you choose to deliver some pieces of optimization advice in a batch.
You are advised to view and deliver the optimization advice on the M2000. If an optimization task is started using MML commands, the M2000 automatically displays the optimization advice.
To confirm and deliver the optimization advice, perform the following operations:
  1. On the M2000 client, choose SON > LTE Adaptive ICIC in the traditional style, or double-click SON on the Application Center tab page and then choose Self Optimization > LTE Adaptive ICIC in the application style.
    The LTE Adaptive ICIC window is displayed.
  2. On the Optimization Management tab page, click the Optimization Advice tab page.
  3. On the Optimization Advice tab page, select optimization advice and click to deliver it.
    The progress bar shows the progress of the delivery and implementation of the optimization advice, as shown in Figure 6-5.
    Figure 6-5 Optimization Advice tab page
The optimization advice involves the following fields:
  • CGI (MCC-MNC-eNodeB ID-Cell ID)
  • eNodeB Name
  • Cell Name
  • DlEarfcn
  • DlBandWidth
  • UL BandMode
  • UL Suggestion
  • DL BandMode
  • DL Suggestion
  • Cell FDD TDD Indication
  • Generated On
  • Execution Time
  • Operation Type
  • Operation Status
  • Rollback Time

6.4.8 Reconfiguration

Using the M2000

To reconfigure adaptive ICIC on the M2000 client, perform the following operations as required.
If...
Then...
Modify parameters for an optimization zone.
  • Choose Configuration > eCoordinator Settings in the traditional style, or double-click Configuration on the Application Center tab page and then choose Settings > eCoordinator Settings in the application style.
    The eCoordinator Settings window is displayed.
  • On the Zone Settings tab page, click to modify parameters for an optimization zone.
Modify the parameter policy.
  • Choose SON > LTE Adaptive ICIC in the traditional style, or double-click SON on the Application Center tab page and then choose Self Optimization > LTE Adaptive ICIC in the application style.
    The LTE Adaptive ICIC window is displayed.
  • On the Parameter Policy tab page, click to modify optimization parameters.
NOTE:
If an optimization task using a parameter policy is currently underway, modifying the Optimization Type parameter of the parameter policy will restart this task. The optimization period for an optimization task restarts from the time when the optimization task is restarted.
Modify the execution mode.
  • Choose SON > LTE Adaptive ICIC in the traditional style, or double-click SON on the Application Center tab page and then choose Self Optimization > LTE Adaptive ICIC in the application style.
    The LTE Adaptive ICIC window is displayed.
  • Click the Optimization Management tab page and click . In the Modify Optimization Task dialog box, change the value of Execution Mode.

Using MML Commands

To reconfigure adaptive ICIC using MML commands, perform the following operations as required.
If...
Then...
Modify an optimization zone.
Run the ADD OPTIZONE command to add a zone.
Modify an optimization object.
Run the ADD OPTIOBJ command to add an object.
Modify the parameters for adaptive ICIC.
Run the MOD AICICOPTIPARA command.
NOTE:
If an optimization task using a parameter policy is currently underway, modifying the Optimization Type parameter of the parameter policy will restart this task. The optimization period for an optimization task restarts from the time when the optimization task is restarted.
Modify the parameters for an optimization task.
Run the MOD OPTIFEATURE command.

6.4.9 Deactivation

Using the M2000

Select the adaptive ICIC feature on the M2000 and click to deactivate it.

Using MML Commands

Run the MOD OPTIFEATURE command with Feature Switch set to OFF(OFF) to stop the optimization task.

6.5 Performance Monitoring

After adaptive ICIC is activated, check the changes in the following items:
  • Average uplink and downlink edge spectral efficiencies
  • Number of times different modulation and coding scheme (MCS) indexes are scheduled in the uplink and downlink
These changes reflect the effect of adaptive ICIC. The average edge spectral efficiency can be calculated using the following formula:
Average edge spectral efficiency = Total bits of user data from CEUs in a cell/(Total duration for transmission of CEU data in a cell x Average number of PRBs used by CEUs in a cell)
Table 6-4 lists the counters used to monitor adaptive ICIC.
Table 6-4 Counters used to monitor adaptive ICIC
Counter ID
Counter Name
Description
1526728475
L.Thrp.bits.UL.CEU
Total bits of user data received at the PDCP layer from uplink CEUs in a cell
1526728476
L.Thrp.Time.UL.CEU
Total duration for the PDCP layer receiving user data from uplink CEUs in a cell
1526728477
L.Thrp.bits.DL.CEU
Total bits of user data transmitted at the PDCP layer to the downlink CEUs in a cell
1526728478
L.Thrp.Time.DL.CEU
Total duration for the PDCP layer transmitting user data to the downlink CEUs in a cell
1526728479
L.ChMeas.PRB.UL.CEU.Used.Avg
Average number of PRBs used by the uplink CEUs in a cell
1526728480
L.ChMeas.PRB.DL.CEU.Used.Avg
Average number of PRBs used by the downlink CEUs in a cell
1526727444 to 526727475
L.ChMeas.PDSCH.MCS.0 to L.ChMeas.PDSCH.MCS.31
Number of times MCS index 0 is scheduled on the PDSCH to Number of times MCS index 31 is scheduled on the PDSCH
1526727412 to 1526727443
L.ChMeas.PUSCH.MCS.0 to L.ChMeas.PUSCH.MCS.31
Number of times MCS index 0 is scheduled on the PUSCH to Number of times MCS index 31 is scheduled on the PUSCH
1526728262
L.Thrp.Time.DL
Total transmit duration of downlink PDCP SDUs in a cell

6.6 Parameter Optimization

The parameters of adaptive ICIC that can be optimized are related to the optimization period, optimization zone, and optimization objects.
  • The Optimization Period parameter specifies how often the ECO6910 analyzes network conditions and provides the optimization advice.
    • If the parameter value is too large, the cell mode and network performance remain stable for a long period. However, the cell mode cannot be updated in a timely manner if the interference or cell load varies, which may adversely affect network performance.
    • If the parameter value is too small, the ECO6910 can trace changes in network conditions quickly and provide the appropriate optimization advice. However, the ECO6910 will be heavily loaded for a long period and may cause fluctuations in network performance.
      In most cases, retain the default value of the Optimization Period parameter, which is Day_7(7 Days). The parameter value can be changed as required. For details, see 6.4.8 Reconfiguration.
  • Optimization objects are cells to be optimized by adaptive ICIC. All of the cells to be optimized form an optimization zone. You can add or remove objects to adjust the range of an optimization zone. It is recommended that cells providing continuous coverage be selected to form an optimization zone. For details, see 6.4.8 Reconfiguration.

6.7 Troubleshooting

Optimization Task Startup Failure

If an optimization task fails to start, perform the following operations:
  1. Check whether ALM-51301 Number of Resources Used Exceeding Alarm Threshold Specified by License has been reported.
    • If so, clear the alarm by following the procedures provided in ECO6910 Alarm Reference.
    • If not, go to 2.
  2. Check whether ALM-51304 Task Running Abnormal has been reported.
    • If so, clear the alarm by following the procedures provided in ECO6910 Alarm Reference.
    • If not, contact Huawei engineers.

Optimization Advice Delivery Failure

If the optimization advice fails to be delivered, check whether ALM-51153 eCoordinator and NE Disconnect Alarm has been reported.
  • If so, clear the alarm by following the procedures provided in ECO6910 Alarm Reference.
  • If not, contact Huawei engineers.

No Optimization Advice Generated by Adaptive ICIC

When the optimization period arrives but the ECO6910 does not generate any optimization advice, perform the following operations:
  1. Check for a cell using a different frequency or bandwidth from its neighboring cells in the optimization zone.Adaptive ICIC applies only when neighboring cells use the same frequency and bandwidth. If a cell in the optimization zone uses a different frequency or bandwidth from its neighboring cells, the ECO6910 does not generate any optimization advice for the cell. If all of the neighboring cells in the optimization zone use the same frequency and bandwidth but the ECO6910 does not generate any optimization advice, go to 2.
  2. Check the average inter-cell interference in the optimization zone. For details, see 6.2 Required Information.When the distance between eNodeBs is large or the number of CEUs is small in a network, inter-cell interference is low and therefore the ECO6910 does not generate any optimization advice. If the inter-cell interference reaches a specified value in the optimization zone but the ECO6910 does not generate any optimization advice, contact Huawei engineers.

Alarms related to adaptive ICIC

Table 6-5 lists the alarms related to adaptive ICIC.
Table 6-5 Alarms related to adaptive ICIC
Alarm ID
Alarm Name
NE
Feature ID
Feature Name
51153
eCoordinator and NE Disconnect Alarm
ECO6910
None
None
51301
Number of Resources Used Exceeding Alarm Threshold Specified by License
ECO6910
SEFD-080107
License Management
51304
Task Running Abnormal
ECO6910
SEFD-080201
SEFD-080202
SEFD-080203
SEFD-080204
SEFD-080205
SEFD-080206
SEFD-080208
SEFD-080210
SEFD-080212
Automatic Neighbor Relation-GSM
Automatic Intra-Frequency Neighbor Relation-UMTS
Automatic Inter-Frequency Neighbor Relation-UMTS
GSM to UMTS Automatic Neighbor Relation-GSM
UMTS to GSM Automatic Neighbor Relation-UMTS
Scrambling Code Self-Optimization-UMTS
GSM to LTE TDD Automatic Neighbor Relation-GSM
UMTS to LTE TDD Automatic Neighbor Relation-UMTS
Adaptive Inter-Cell Interference Coordination-LTE TDD

7 Parameters

There are no specific parameters associated with this feature.

8 Counters

There are no specific counters associated with this feature.

Budi Prasetyo

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