When deploying the Huawei OLT MA5600T series or MA5800T series model, selecting the right split ratio is crucial to ensure optimal network performance. A well-balanced split ratio impacts signal strength, network reliability, and overall service quality. This guide focuses on best practices for configuring split ratios for Huawei OLT service boards, particularly GPFD/GPHF/GPSF/CGHF/CSHF, to maximize efficiency and avoid common deployment issues.

Understanding Huawei OLT Split Ratios

In a GPON or 10G-PON(XGPON or XGS-PON) architecture, the split ratio refers to the number of ONTs connected to a single OLT port via an optical splitter. Typical split ratios include 1:32, 1:64, 1:128, and 1: 256 with each having its own advantages and trade-offs:

• 1:32 – Best performance with minimal signal loss. Ideal for high-bandwidth applications.

• 1:64 – Balanced approach, widely used in FTTH deployments. e.g. GPON boards like GPFD B+ Max. split radio is 1:64

• 1:128 – Maximizes coverage but may lead to higher signal attenuation and potential performance degradation. e.g. GPON boards like GPHF C+ Max. split radio is 1:128.

• 1: 256 –  Suitable only for specialized XGPON/XGSPON deployments with strong signal management. Requires premium optical components to maintain signal quality. e.g. 10G-PON boards like CGHF/CSHF Max. split radio: 1: 256

Table 1: Split Radio for Common Huawei OLT PON Boards 

*Max. split radio primarily a theoretical maximum split ratio just only as a reference. In real-world deployments, this level of splitting would result in excessive signal loss, requiring optical amplification or regeneration to maintain acceptable performance.

How to Calculate the Actual Split Ratio when the xPON Uses the Multi-level Optical Splitting Mode

When the xPON uses the multi-level optical splitting, the actual split ratio can be calculated as follows:

Actual split ratio=multiplication of numbers of the optical splitting of each level

For example, in theory, the proposed split ratio of the GPON is less than 64. In the actual operation, 1:8 optical splitting is used in the first level and 1:16 optical splitting is used in the second level. 8 x 16 = 128 > 64. The actual split ratio exceeds the theoretical value. As a result, services fail to be provided if the split ratio in the service planning is very large. 

Case Study: ONT Performance at 1:128 Split Ratio

A customer reported that when the EG8145V5 ONT is connected to a GPHF service board at a 1:64 split ratio, it works well. However, when using a 1:128 split ratio, the ONT experiences low optical power issues.

Key Factors Affecting Performance at 1:128

1. Optical Power Budget – GPON networks typically operate within a 28 dB power budget, and XGS-PON networks within 31 dB. A higher split ratio increases attenuation, potentially exceeding this limit.

2. Fiber Length & Loss – Long-distance connections and additional fiber splices contribute to further signal degradation.

3. Splitter Insertion Loss – Each optical splitter introduces loss, approximately 3-4 dB per split stage. At 1:128, cumulative loss can be significant.

4. ONT Sensitivity – Different ONTs have varying receiver sensitivity levels, affecting performance in high-loss environments.

Best Practices for OLT Deployment

To optimize Huawei OLT deployment, follow these recommendations:

1. Choose the Right Split Ratio:

   • For high-speed enterprise or 4K video applications, use 1:32 or 1:64.

   • For cost-effective residential FTTH deployments, 1:64 is the recommended limit.

   • Avoid 1:128 unless necessary, and only use it with strong signal conditions.

2. Perform Optical Power Measurements:

   • Ensure the OLT output power meets the required range.

   • Measure optical loss after splitters to confirm signal strength is within budget.

3. Use High-Quality Components:

   • Invest in low-loss optical splitters to minimize signal attenuation.

   • Use premium fiber cables and proper splicing techniques to reduce additional losses.

4. Consider Optical Amplifiers or Boosters:

   • If higher split ratios are needed, deploy EDFA (Erbium-Doped Fiber Amplifiers) or optical signal regenerators to compensate for signal loss.

Conclusion

Selecting the right split ratio for a Huawei OLT is essential for ensuring a stable and high-performance fiber network. While 1:64 is a common industry standard for balanced performance, 1:128 should only be used with careful planning and sufficient power budget. By following best practices, service providers can minimize signal degradation, improve ONT performance, and enhance overall network efficiency.

For further assistance on Huawei OLT deployment, feel free to email us at sales@xponshop.com.