Huawei Add UCELLLDM

Add cell oriented LDM algorithm parameters(ADD UCELLLDM) Function

Use this command to add cell-oriented LDM algorithm parameters.

Note

1. UL LDR trigger threshold >= UL LDR release threshold

2. DL LDR trigger threshold >= DL LDR release threshold

3. UL OLC trigger threshold >= UL OLC release threshold

4. DL OLC trigger threshold >= DL OLC release threshold

5. UL OLC trigger threshold > UL LDR trigger threshold

6. UL OLC release threshold >= UL LDR release threshold

7. DL OLC trigger threshold > DL LDR trigger threshold

8. DL OLC release threshold >= DL LDR release threshold

9. UL OLC trigger threshold >= UL handover access threshold

10. DL OLC trigger threshold >= DL total power threshold

11. HSUPA auto retransmit load trigger threshold >= HSUPA auto retransmit load release threshold

12. UL load restricted trigger threshold ratio >= UL load restricted release threshold ratio

The referenced parameters of CAC above are set in ADD UCELLCAC and MOD UCELLCAC, and they can be listed by LST UCELLCAC.

Parameters

Parameter ID Parameter Name

Parameter Description

CellId Cell ID Meaning: The logical cell ID uniquely identifies a

cell in a radio network.

The logical cell ID is configured at the BSC6900. The BSC6900 sends the cell ID to the base station during a cell setup procedure. The mapping between logical cell IDs and local cell IDs are configured at the BSC6900.

The BSC6900 supports a maximum of 5100 logical cells. Logical cells are uniquely but not necessarily consecutively numbered within a BSC6900. For example, you can set the ID of a logical cell to 0 and that of another logical cell to 2.

For clear and easy identification, adhere to the following numbering principles:

Specify different number ranges for logical cells in different subracks. For example, you can specify the range of 0 to 899 for the logical cells in subrack 0 (MPS) and the range of 900 to 1799 for the logical cells in subrack 1 (EPS).For detailed information about this parameter, see 3GPP TS 25.401.

GUI Value Range: 0~65535

Unit: None

Actual Value Range: 0~65535

MML Default Value: None

Recommended Value: None

Parameter Relationship: None

Service Interrupted After Modification : No (No impact on the UE in idle mode)

Impact on Network Performance: None

UlLdrTrigThd UL LDR trigger threshold

Meaning: If the ratio of UL load of the cell to the uplink capacity is not lower than this threshold, the UL load reshuffling function of the cell is triggered. After the basic congestion state of the cell load is released, the system no longer implements the LDR action. Because the load fluctuates, the difference between the LDR release threshold and trigger threshold should be higher than 10%. The ping-pong effect of the preliminary congestion state may occur.


Unit: %


MML Default Value: 55

Recommended Value: 55

Parameter Relationship: The value of this parameter must satisfy the following relationship:

UlLdrTrigThd >= UlLdrRelThd; UlOlcTrigThd > UlLdrTrigThd; UlNonCtrlThdForOther(See ADD UCELLCAC) >= UlLdrTrigThd.


Impact on Network Performance: The lower the LDR trigger and release thresholds are, the easier the system enters the preliminary congestion status, the harder it is released from this status, the easier the LDR action is triggered, and the more likely the users are affected. But, the admission success rate becomes higher since the resources are preserved. The carrier shall make a trade-off between these factors.

UlLdrRelThd UL LDR release threshold

Meaning: If the ratio of UL load of the cell to the uplink capacity is lower than this threshold, the UL load reshuffling function of the cell is stopped. After the basic congestion state of the cell load is released, the system no longer implements the LDR action. Because the load fluctuates, the difference between the LDR release threshold and trigger threshold should be higher than 10%. The ping-pong effect of the preliminary congestion state may occur.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: UlLdrTrigThd >= UlLdrRelThd; UlOlcRelThd >= UlLdrRelThd.



DlLdrTrigThd DL LDR trigger threshold

Meaning: If the ratio of DL load of the cell to the downlink capacity is not lower than this threshold, the DL load reshuffling function of the cell is triggered. After the basic congestion state of the cell load is released, the system no longer implements the LDR action. Because the load fluctuates, the difference between the LDR release threshold and trigger threshold should be higher than 10%. The ping-pong effect of the preliminary congestion state may occur.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: DlLdrTrigThd >= DlLdrRelThd; DlOlcTrigThd > DlLdrTrigThd; DlOtherThd(See ADD UCELLCAC) >= DlLdrTrigThd.



DlLdrRelThd DL LDR release threshold

Meaning: If the ratio of DL load of the cell to the downlink capacity is lower than this threshold, the DL load reshuffling function of the cell is stopped. After the basic congestion state of the cell load is released, the system no longer implements the LDR

action. Because the load fluctuates, the difference between the LDR release threshold and trigger threshold should be higher than 10%. The ping-pong effect of the preliminary congestion state may occur.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: DlLdrTrigThd >= DlLdrRelThd; DlOlcRelThd >= DlLdrRelThd.


Impact on Network Performance: The lower the LDR trigger and release thresholds are, the easier the system enters the preliminary congestion status, the harder it is released from this status, the easier the LDR action is triggered, and the more likely the users are affected. But, the admission success rate becomes higher since the resources are preserved.

The carrier shall make a trade-off between these factors.

UlOlcTrigThd UL OLC trigger threshold

Meaning: If the ratio of UL load of the cell to the uplink capacity is not lower than this threshold, the UL overload and congestion control function of the cell is triggered. The value of the OLC release threshold should not be much lower than or close to the OLC trigger threshold, or the system state may have a ping-pong effect. The recommended difference between the OLC release threshold and the OLC trigger threshold is higher than 10%. It is desirable to set the two parameters a bit higher given that the difference between OLC trigger threshold and OLC release threshold is fixed.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: UlOlcTrigThd > UlLdrTrigThd; UlOlcTrigThd >= UlOlcRelThd; UlOlcTrigThd >= UlNonCtrlThdForHo(See ADD UCELLCAC).


Impact on Network Performance: The lower the OLC trigger threshold is, the easier the system is in the overload status. An excessively low value of the OLC trigger threshold is very detrimental to the system performance. The lower the OLC release threshold is, the harder the system releases the overload.

UlOlcRelThd UL OLC release threshold

Meaning: If the ratio of UL load of the cell to the uplink capacity is lower than this threshold, the UL overload and congestion control function of the cell is stopped. The value of the OLC release threshold should not be much lower than or close to the OLC trigger threshold, or the system state may have a ping-pong effect. The recommended difference between the OLC release threshold and the OLC trigger threshold is higher than 10%. It is desirable to set the two parameters a bit higher given that the difference between OLC trigger threshold and OLC release threshold is fixed.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: UlOlcTrigThd >= UlOlcRelThd; UlOlcRelThd >= UlLdrRelThd.



DlOlcTrigThd DL OLC trigger threshold

Meaning: If the ratio of DL load of the cell to the downlink capacity is not lower than this threshold, the DL overload and congestion control function of the cell is triggered. The value of the OLC release threshold should not be much lower than or close to the OLC trigger threshold, or the system state may have a ping-pong effect. The recommended difference between the OLC release threshold and the OLC trigger threshold is higher than 10%. It is desirable to set the two parameters a bit higher given that the difference between OLC trigger threshold and OLC release threshold is fixed.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: DlOlcTrigThd >= DlOlcRelThd; DlOlcTrigThd > DlLdrTrigThd; DlOlcTrigThd >= DlCellTotalThd.



DlOlcRelThd DL OLC release threshold

Meaning: If the ratio of DL load of the cell to the downlink capacity is lower than this threshold, the DL overload and congestion control function of the cell is stopped. The value of the OLC release threshold should not be much lower than or close to the OLC trigger threshold, or the system state may have a ping-pong effect. The recommended difference between the OLC release threshold and the OLC trigger threshold is higher than 10%. It is desirable to set the two parameters a bit higher given that the difference between OLC trigger threshold

and OLC release threshold is fixed.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: DlOlcTrigThd >= DlOlcRelThd; DlOlcRelThd >= DlLdrRelThd.



DlLdTrnsHysTime DL State Trans

Meaning: If the DL load state of the cell is lasted longer than this threshold, the DL load state of the

Hysteresis threshold

cell transfers.


Unit: ms







HsupAuRetrnsLdTrigThd

HSUPA auto retransmit load trigger threshold

Meaning: HSUPA auto retransmit load trigger threshold.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: HsupAuRetrnsLdTrigThd >= HsupAuRetrnsLdRelThd



HsupAuRetrnsLdRelThd HSUPA auto retransmit load release threshold

Meaning: HSUPA auto retransmit load release threshold.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: HsupAuRetrnsLdTrigThd >= HsupAuRetrnsLdRelThd



TrigRatioforUlRTWP UL load restricted trigger threshold ratio

Meaning: UL load restricted trigger threshold ratio.If the state of the load for the TTI switchover algorithm is normal and the current uplink RTWP of cell is greater than the product of "Maximum Target Uplink load Factor" and "UL load restricted trigger threshold ratio", then the state of the load for the TTI switchover algorithm is set to restricted.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: TrigRatioforUlRTWP >= RelRatioforUlRTWP


Impact on Network Performance: If the UL RTWP load is in restricted state, the RNC can change the TTI of the UE from 2 ms to 10 ms. If this parameter is set too large, the TTI of the UE may be changed to 2ms in the case of overloading. This may affect the cell capacity and fair diversity. If this parameter is set too small, the value of the TTI may be changed by mistake when the load is reduced. This may affect KPIs and UE QoS.

RelRatioforUlRTWP UL load restricted release threshold ratio

Meaning: UL load restricted release threshold ratio.If the state of the load for the TTI switchover algorithm is restricted and the current uplink RTWP of cell is smaller than the product of "Maximum Target Uplink load Factor" and "UL load restricted release threshold ratio", then the state of the load for the TTI switchover algorithm is set to normal.


Unit: %




Parameter Relationship: The value of this parameter must satisfy the following relationship: TrigRatioforUlRTWP >= RelRatioforUlRTWP


Impact on Network Performance: If the UL RTWP load is in restricted state, the RNC can change the TTI of the UE from 2 ms to 10 ms. If this parameter is set too large, the TTI of the UE may be changed to 2ms in the case of overloading. If the RTWP load fluctuate acutely, it may lead to ping-pong switchover of the TTI. If this parameter is set too small, the value of the TTI may fail to be changed to 2 ms in time. This may affect the QoS of a UE.

FairnessThd Fairness threshold

Meaning: This parameter specifies the fairness threshold that is set between the R99 BE service and HSUPA service. When the ratio of the R99 BE service throughput to the HSUPA service throughput exceeds the value of this parameter, unfairness exists between the R99 BE service and HSUPA service. That is, the R99 BE service rate is higher than the HSUPA service rate.


Unit: None

Actual Value Range: 0~3, step: 0.01





Impact on Network Performance: If this parameter is set to a small value, the conditions of unfairness between the R99 BE service rate and HSUPA service rate can be easily met. In this case, the rate reduction of the R99 BE service is easily triggered to improve the throughput of the HSUPA service. The decrease in the rate of the R99 BE service also leads to the decrease in the R99 BE service throughput. If this parameter is set to a large value, the rate reduction of the R99 BE service is not easily triggered.

Example

Add the load monitoring parameters of cell 1.ADD UCELLLDM: CellId=1, UlLdrTrigThd=55, UlLdrRelThd=45, DlLdrTrigThd=70, DlLdrRelThd=60, UlOlcTrigThd=95, UlOlcRelThd=85, DlOlcTrigThd=95,

DlOlcRelThd=85, DlLdTrnsHysTime=1000, HsupAuRetrnsLdTrigThd=70, HsupAuRetrnsLdRelThd=50, TrigRatioforUlRTWP=73, RelRatioforUlRTWP=60, FairnessThd=150;

Documents

Huawei Add UCELLLDM