Strategies to reduce Call Drops on TCH Uplink Quality

RAN
,
1

Hi everyone.

How can we reduce call drops on TCH due to uplink quality issues?

2

Any uplink interference?

3

Common Causes of Call Drops on TCH Uplink Quality:

  • Interference
  • Hardware issues
  • VSWR (Voltage Standing Wave Ratio)
  • High Timing Advance (TA)
4

To address TCH uplink call drops, a thorough technical investigation is essential to identify the root cause, whether it stems from congestion, poor coverage (often related to antenna tilting or power adjustments), or interference. Based on the findings, the following actions can be taken:

  1. Increase Uplink RLC RETX Threshold
    • Adjust the retransmission threshold to allow more retries for uplink data before triggering a failure.
  2. Adjust N310 and T30 Thresholds
    • Increase these parameters to provide additional time for error correction and recovery, reducing premature call drops.
  3. Review Neighbor Relations and Handover Offsets
    • Check the configuration of neighbor relations (NBRs) and fine-tune handover offsets.
    • Evaluate 4G and 3G priorities to align with the desired service objectives.
  4. Implement Interference Mitigation Features
    • Enable and optimize interference management features to minimize the impact on uplink quality.

The mitigation measures depend on the technology in use (2G, 3G, or 4G) and the availability of relevant features. Here are some additional steps:

  1. Hardware Issue Investigation
    • Open a ticket with the NFM team to investigate potential hardware issues in the area.
    • Check for anomalies such as faulty repeaters or other equipment causing interference.
  2. Review and Verify Feature Implementations
    • Ensure that appropriate features are applied in the network configuration.
    • Be cautious of certain features that might cause temporary deterioration, such as Huawei’s CloudAIR.
    • Optimize and fine-tune these features to stabilize network performance over time.