16 Huawei 3G Features Trial Report_DEC 2013 - CQI Adjustment Based on Dynamic BLER Target

HUAWEI 3G FEATURES TRIAL REPORT CQI Adjustment Based on Dynamic BLER Target

Feature Details Feature Name: CQI Adjustment Based on Dynamic BLER Target Feature Code: WRFD-030010 Trial Period: 16 Dec 2013 – 20 Dec 2013 Huawei Representative: Mr. N.S.K Kishore, Mr. Youjianjun (Woods) Idea Representative: Mr. Venkata Sivaprasad

Feature Description The CQI measures the channel conditions of a UE and is reported from the UE to the NodeB. Without this feature, the NodeB determines an appropriate TBS based on the reported CQI, system resources, and the TFRC policy. If the reported CQI and related conditions remain the same, the NodeB does not change the TBS because it does not consider the ever-changing radio environments. The constant changes in radio environments, caused by multipath effects and UE mobility, lead to fluctuating channel quality. Under these circumstances, choosing a TBS based on the reported CQI makes it difficult to always achieve the optimum downlink throughput. With the feature CQI adjustment based on dynamic BLER target, the NodeB monitors the channel quality fluctuations for HSDPA users in a cell in real time and dynamically selects a proper BLER target based on the monitoring result. The NodeB then uses the BLER target to adjust the CQI reported by the UE. Based on the adjusted CQI, the NodeB determines an appropriate TBS to achieve higher downlink throughput for HSDPA users and higher cell throughput. CQI adjustment based on dynamic BLER target is performed in each TTI. The following describes the adjustment process: 1. Based on the CQI reported by the UE, the NodeB checks the actual radio environment, which is affected by multipath effects and UE mobility. 2. Based on the actual radio environment and channel quality of the UE, the NodeB obtains an optimum BLER target, which helps to achieve the highest possible throughput for the UE. 3. Based on the ACK, NACK, or DTX indication from the UE in the current TTI and on the optimum BLER target, the NodeB calculates the CQI offset, which can be a positive or negative number. The NodeB then uses the CQI offset to adjust the CQI. 4. Based on the adjusted CQI, the NodeB selects an appropriate TBS by using the TFRC algorithm.

Objective This test case aims to verify that CQI Adjustment Based on Dynamic BLER Target.

Idea Cellular Ltd. – Internal ConfidentialPage 1


Test Network Standard Network of Acceptance: (NE: RNC1, NodeB1, CELL_A11) Post Verification on Test NodeB, to be implemented in one RNC to check KPI performance

Prerequisites & MoP : 1. WCDMA system is operational. 2. UE is registered with the HLR to allow interactive services with a maximum rate in the downlink. 3. NodeB license for CQI Adjustment Based on Dynamic BLER Target need to be activated for the Cell. 4. CELL_A11 supports HSDPA and HSUPA and is operating properly. To check the cell status, run the following command on the RNC1 LMT: DSP UCELL: DSPT=BYCELL, CellId=< CELL_A11>; 5. Enable CQI Adjustment Based on Dynamic BLER Target in the cell. SET ULOCELLMACHSPARA: ULOCELLID=A11, CQIADJALGOFNONCON=CQI_ADJ_BY_DYN_BLER; 6. UE perform download from FTP Server. Monitor the HSDPA throughput

7. Disable CQI Adjustment Based on Dynamic BLER Target in the cell SET ULOCELLMACHSPARA: ULOCELLID=A11, CQIADJALGOFNONCON= NO_CQI_ADJ; 8. UE perform download from FTP Server. Monitor the HSDPA throughput



8. From the above HSDPA throughput result it is observed that there is an increase in the average HSDPA throughput when the feature is active.

KPI Comparison This feature has been activated in RNC 601 on 16 Nov’13 morning. 1. HSDPA Throughput improvement


HUAWEI 3G FEATURES TRIAL REPORT CQI Adjustment Based on Dynamic BLER Target It is observed that after activating the feature there is an increase in VS.HSDPA.MeanChThroughput and below is the comparison report for the same

Below graph shows the increase in HSDPA throughput trend after activating the feature

2. Increase in Data Output.Mean The average cell throughput at the MAC-hs/MAC-ehs layer has increased after activating the feature below is the observation:



RNC 601 KPI Analysis is attached for reference.

RNC 601 KPI Analysis Report


16 Huawei 3G Features Trial Report_DEC 2013 - CQI Adjustment Based on Dynamic BLER Target

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