Enable LAOFD-070202 Inter-eNodeB CA based on Coordinated BBU if operators require carrier aggregation between inter-BBU cells in multi-BBU interconnection scenarios. In addition, LAOFD-070202 Inter-eNodeB CA based on Coordinated BBU requires that LAOFD-001001 LTE-A Introduction and optionally LAOFD-001002 Carrier Aggregation for Downlink 2CC in 40MHz be enabled. For the deployment scenarios for the two prerequisite features, see 6.1 When to Use LAOFD-001001 and LAOFD-001002.
8.2 Required Information
For details, see 6.2 Required Information.
This CA feature shares system resources with the SFN, UL CoMP, and CSPC features. Before deploying this CA feature, contact Huawei engineers for a resource audit.
8.3 Planning
RF Planning
For details about RF planning, see 6.3 Planning.
Network Planning
Deploy multi-BBU interconnection, in addition to network planning described in 6.3 Planning.
Hardware Planning
Use LBBPd or UBBP as baseband processing units. Do not use LBBPc or UMDUa3. For the antenna modes of cells supported by LBBPd and UBBP boards, see hardware planning described in 6.3 Planning.
8.4 Deployment
CA works between two or three inter-frequency cells.
8.4.1 Requirements
Operating Environment
None
NEs
In addition to the requirements described in 6.4.1 Requirements, CA in centralized multi- BBU interconnection scenarios has the following requirements:
l A USU is required for data exchange between BBUs.
l The same software version runs on the BBUs to be interconnected.
l LMPT and LBBPc cannot be used for USU-based multi-BBU interconnection.
Transmission Networking
The BBUs must be time-synchronized.
License
Deploying LAOFD-070202 Inter-eNodeB CA based on Coordinated BBU requires the following licenses:
l In CA-group-based configuration mode, each eNodeB on which any CA group includes an inter-eNodeB cell requires one sales unit of the license for LAOFD-070202 Inter- eNodeB CA based on Coordinated BBU.
l In frequency-based or adaptive configuration mode, if FreqCfgCaOverBBUsSwitch under ENodeBAlgoSwitch.OverBBUsSwitch is on, each eNodeB on which any cell is accompanied by an inter-BBU SCell requires one sales unit of the license for
LAOFD-070202 Inter-eNodeB CA based on Coordinated BBU.
In addition, each cell involved in CA requires one sales unit of the license for
LAOFD-001001 LTE-A Introduction and, if the total bandwidth of the cells is greater than 20 MHz and less than or equal to 40 MHz, one sales unit of the license for LAOFD-001002 Carrier Aggregation for Downlink 2CC in 40MHz.
Feature ID Feature
Name Model LicenseControl Item NE Sales Unit
LAOFD-00 1001 LTE-A Introduction LT1SA020C A00 LTE-A Introduction (FDD)
eNodeB per cell
LAOFD-00 1002 Carrier Aggregation for Downlink 2CC in 40MHz LT1SA040C A00 Carrier Aggregation for Downlink 2CC in 40MHz (FDD)
eNodeB per cell
LAOFD-07 0202 Inter-eNodeB CA based on Coordinated BBU LT1SCAFB CB00 Inter-eNodeB CA based on Coordinated BBU (FDD)
eNodeB per eNodeB
Others
The prerequisite features for LAOFD-070202 Inter-eNodeB CA based on Coordinated BBU must be activated.
8.4.2 Data Preparation
The parameters described in 6.4.2 Data Preparation apply to LAOFD-070202 Inter-eNodeB CA based on Coordinated BBU. In addition, make data preparation as follows:
l In CA-group-based configuration mode, set the following switch on. In addition, configure CAGROUP, CAGROUPCELL, and CaGroupSCellCfg MOs on each BBU and ensure that the CAGROUP and CAGROUPCELL configurations of the BBUs involved in CA are consistent. If the configurations are inconsistent, CA does not work.
Param eter Name
Paramete
r ID Setting Notes Data Source
CA Algorit hm Switch ENodeBA lgoSwitch. CaAlgoSw itch The DistributeCloudbbCaS- witch(DistributeCloudbbCaSwitch) option specifies whether to enable CA in the distributed multi-BBU
interconnection architecture.
l If this option is selected, this type of CA applies to the cells served by the eNodeB.
l If this option is deselected, this type of CA is disabled for the cells served by the eNodeB.
User-defined
Param eter Name
Paramete
r ID Setting Notes Data Source
OverB BUsSw itch ENodeBA lgoSwitch. OverBBUs Switch
The option FreqCfgCaOverBBUsS- witch specifies whether to enable inter- BBU CA or not in frequency-based or adaptive configuration mode. This switch applies only to LTE FDD cells. It takes effect only when FreqCfgSwitch under the ENodeBAlgoSwitch.CaAlgoSwitch parameter is on.
l If multi-BBU interconnection is deployed on the network, select this option to enable inter-BBU CA. l If multi-BBU interconnection is not
deployed on the network, do not select this option. If you select it, inter-BBU CA may occur but fail. This prolongs the time for SCell configuration.
User-defined CA Algorit hm Switch ENodeBA lgoSwitch. CaAlgoSw itch The DistributeCloudbbCaS- witch(DistributeCloudbbCaSwitch) option specifies whether to enable CA in the distributed multi-BBU
interconnection architecture.
l If this option is selected, this type of CA applies to the cells served by the eNodeB.
l If this option is deselected, this type of CA is disabled for the cells served by the eNodeB.
User-defined
NOTE
For details about USU configurations, see USU3910-based Multi-BBU Interconnection.
8.4.3 Precautions
In addition to the precautions described in 6.4.3 Precautions, a penalty mechanism applies to eX2 route setups. If three consecutive attempts of an eNodeB to set up an eX2 route to an inter-BBU cell fail, the eNodeB prohibits the subsequent 30 attempts on the route.
8.4.4 Hardware Adjustment
Besides the hardware adjustment described in 6.4.4 Hardware Adjustment, CA in multi- BBU interconnection scenarios requires a USU to connect BBUs for data exchange between BBPs. For details about the cable connections, see USU3910-based Multi-BBU
8.4.5 Activation
CA-Group-based Configuration
l If the network is deployed using the centralized multi-BBU interconnection architecture, perform the operations described in 6.4.5 Activation on each BBU.
l If the network is deployed using the distributed multi-BBU interconnection architecture, perform the operations described in 6.4.5 Activation on each BBU and run the following command for the serving eNodeB of each candidate PCell to set
DistributeCloudbbCaSwitch on:
MOD ENODEBALGOSWITCH:CAALGOSWITCH=DistributeCloudbbCaSwitch-1;
Frequency-based or Adaptive Configuration
l If the network is deployed using the centralized multi-BBU interconnection architecture, perform the operations described in 6.4.5 Activation on each BBU and run the following command for each BBU to set FreqCfgCaOverBBUsSwitch on:
MOD ENODEBALGOSWITCH:OVERBBUSSWITCH=FreqCfgCaOverBBUsSwitch-1;
l If the network is deployed using the distributed multi-BBU interconnection architecture, perform the operations described in 6.4.5 Activation on each BBU and also perform the following steps:
– Run the following command on each BBU to set FreqCfgCaOverBBUsSwitch on: MOD ENODEBALGOSWITCH:OVERBBUSSWITCH=FreqCfgCaOverBBUsSwitch-1;
– Run the following command on the serving eNodeB of each candidate PCC to set DistributeCloudbbCaSwitch on:
MOD ENODEBALGOSWITCH:CAALGOSWITCH=DistributeCloudbbCaSwitch-1;
8.4.6 Activation Observation
For details, see 6.4.6 Activation Observation.
8.4.7 Deactivation
CA-Group-based Configuration
l If the network is deployed using the centralized multi-BBU interconnection architecture, delete inter-BBU cells from each CA group on a BBU. Inter-BBU cells have different eNodeB IDs from the local BBU. The following is an example of the command: RMV CAGROUPCELL:CAGROUPID=0,LOCALCELLID=0,ENODEBID=1234;
l If the network is deployed using the distributed multi-BBU interconnection architecture, run the following command for the serving eNodeB of each candidate PCell to set DistributeCloudbbCaSwitch off:
MOD ENODEBALGOSWITCH:CAALGOSWITCH=DistributeCloudbbCaSwitch-0;
Frequency-based or Adaptive Configuration
l If the network is deployed using the centralized multi-BBU interconnection architecture, run the following command on each BBU to set FreqCfgCaOverBBUsSwitch off: MOD ENODEBALGOSWITCH:OVERBBUSSWITCH=FreqCfgCaOverBBUsSwitch-0;
l If the network is deployed using the distributed multi-BBU interconnection architecture, run the following command for the serving eNodeB of each candidate PCell to set DistributeCloudbbCaSwitch off:
8.5 Performance Monitoring
For details, see 6.5 Performance Monitoring.
8.6 Parameter Optimization
For details, see 6.6 Parameter Optimization.
8.7 Troubleshooting
Troubleshooting described in 6.7 Troubleshooting applies to LAOFD-070202 Inter-eNodeB CA based on Coordinated BBU with only an exception at step 4 in the fault handling procedure for CA in CA-group-based configuration mode. In step 4, run the command on each BBU to check whether the configurations are consistent between the eNodeBs. l If the configurations are consistent, go to step 5.
l If the configurations are inconsistent, follow the instructions described in 6.4.5.5 Using MML Commands to configure CaGroupCell MOs to be consistent between the BBUs. Then, check whether the CA-related counters provided in 6.5 Performance Monitoring produce non-zero values. If the counters produce non-zero values, no further action is required. If the counters retain the value of 0, go to step 5.