An upstream reach-extender for 10Gb/s PON applications based on an optimized semiconductor amplifier cascade

Area of Science:

• Optical Engineering
• Telecommunications
• Semiconductor Devices

Background:

• Passive optical networks (PONs) are crucial for broadband access, but limited reach and split ratios restrict their scalability.
• Extending the transmission distance and subscriber capacity in upstream PON paths is a key challenge for network providers.
• Semiconductor optical amplifiers (SOAs) offer a potential solution for signal amplification in optical networks.

Purpose of the Study:

• To develop and demonstrate a novel reach-extender for 10Gb/s PONs.
• To improve the dynamic range and signal integrity of the upstream transmission path.
• To achieve extended reach and higher split ratios without complex dynamic control mechanisms.

Main Methods:

• An optimized cascade of two semiconductor optical amplifiers (SOAs) was designed and implemented.
• The bias current of the second-stage SOA was carefully tuned to enhance performance.
• Experimental validation was performed using an ac-coupled, continuous-mode receiver with a modified ac-coupling constant.

Main Results:

• Over 19dB input dynamic range was achieved.
• Up to 12dB compression of the output dynamic range was realized without dynamic control.
• A transmission reach of 70km and a split ratio of up to 32 were experimentally demonstrated.

Conclusions:

• The optimized SOA cascade effectively extends the reach and split capability of 10Gb/s PONs.
• The proposed solution offers a cost-effective and simple method for enhancing PON performance.
• This technology has the potential to significantly increase the capacity and coverage of fiber-to-the-home networks.