GPON OLT SFP Class C++ Transceiver | 2.5G/1.25G | High Power Budget | Tx 1490nm

Overview

The GPON OLT SFP Class C++ Transceiver is a high-performance optical module designed for Service Providers who require maximum flexibility and density in their Passive Optical Networks (PON). Surpassing the standard Class B+ and Class C+ specifications, this Class C++ module delivers an enhanced optical power budget, enabling operators to drive signals through more complex optical distribution networks (ODN).

Operating under the ITU-T G.984.2 standard, this SFP module provides asymmetric speeds of 2.488 Gbps downstream and 1.244 Gbps upstream. It is specifically engineered for the OLT (Optical Line Terminal) side, transmitting at 1490nm and receiving burst-mode traffic at 1310nm. The “Class C++” designation indicates a higher transmit power and superior receiver sensitivity, making it the ideal choice for overcoming high insertion loss found in networks with 1:128 split ratios or extended transmission distances up to 20km.

Key Features

• Class C++ Power Budget: Delivers the highest standard optical margin (approx. 35dB) for GPON networks.
• High Split Ratio Support: Capable of supporting up to 1:128 split ratios, doubling the subscriber density per port compared to standard Class B+ modules.
• Standard Compliance: Fully compliant with ITU-T G.984.2 GPON and SFP Multi-Source Agreement (MSA).
• Burst Mode Receiver: Advanced 1310nm APD receiver handles burst traffic from multiple ONUs with high sensitivity.
• Form Factor: Hot-pluggable SFP footprint with a single SC/UPC receptacle.
• DDM Support: Real-time Digital Diagnostic Monitoring for optical power, voltage, and temperature.

Applications

• High-Density FTTH: Connecting up to 128 subscribers per single fiber strand to maximize OLT port utilization.
• Rural Broadband: Extending the reach of fiber networks into rural areas where fiber runs are longer and signal loss is higher.
• Legacy Network Upgrades: Replacing older Class B+ modules to improve signal quality on degrading fiber plants without re-cabling.
• Triple Play Services: Delivering reliable high-bandwidth Data, Voice, and Video (IPTV) services.

Specifications

Why Choose Class C++?

In GPON architecture, the optical power budget dictates how many times you can split the fiber signal and how far it can travel. Standard Class B+ modules typically offer a budget around 28dB (suitable for 1:64 splits at moderate distances). Class C+ increases this to ~32dB.

Class C++ pushes the envelope further, often providing a budget range of 33dB to 35dB. This extra headroom is critical for:

1. Network Reliability: It provides a safety margin against aging fiber and dirty connectors.
2. Cost Efficiency: By supporting 1:128 splits, ISPs can serve twice as many customers per OLT card, reducing CAPEX.

FAQ

1. What is the difference between Class B+, C+, and C++?

The main difference is the optical power budget. Class B+ has the lowest power (for 1:32 or 1:64 splits). Class C+ is higher. Class C++ is the highest performance tier, offering higher Transmit Power (Tx) and better Receive Sensitivity (Rx), allowing for 1:128 splits or longer distances.

2. Can I replace a Class B+ module with this Class C++ module?

Yes. Since the module is hot-swappable and follows the same G.984 standard, you can upgrade to Class C++ to improve signal levels. However, ensure your OLT software configuration supports the new module parameters if strict validation is enabled.

3. Does this module work with any GPON ONU?

Yes, it works with any ITU-T G.984 compliant GPON ONU (Optical Network Unit). The Class C++ OLT module simply provides a stronger signal; the ONU does not need to be a special “Class C++” ONU, although the entire link budget depends on both ends.

4. What connector type does this use?

This module uses a simplex SC/UPC connector (Blue). Do not use SC/APC (Green) connectors directly into the module as this causes high insertion loss and reflection.

5. Is this module symmetric or asymmetric?

GPON is inherently asymmetric. This module downloads at 2.5Gbps and uploads at 1.25Gbps. For symmetric speeds, you would need XGS-PON or 10G-EPON technologies.