Optically equalized 10 Gb/s NRZ digital burstmode receiver for dynamic optical networks

Area of Science:

• Optical Engineering
• Digital Communications
• Signal Processing

Background:

• Asynchronous optical networks require receivers capable of handling variable burst lengths and power levels.
• Traditional receivers often necessitate complex linecoding or AC-coupling schemes to manage burst data.
• Existing solutions have limited dynamic range, restricting their applicability in diverse network conditions.

Purpose of the Study:

• To develop a high-performance digital burst-mode optical receiver for 10Gb/s NRZ signals.
• To enhance the dynamic range and versatility of optical receivers for asynchronous network applications.
• To demonstrate a receiver design that minimizes overhead and supports a wide range of burst timescales.

Main Methods:

• A digital burst-mode receiver architecture utilizing an AC-coupled photodiode and a 20 GS/s asynchronous analog-to-digital converter.
• Implementation of digital signal processing for symbol timing, amplitude, and baseline wander correction.
• Characterization using G.709 framing, enhanced Forward Error Correction (FEC), and a pre-FEC Bit Error Rate (BER) of 10^-3 at 10 dB Optical Signal-to-Noise Ratio (OSNR).

Main Results:

• The digital receiver alone achieves a 7 dB burst-to-burst dynamic range.
• Integration of an electronically controlled Semiconductor Optical Amplifier (SOA) extends the dynamic range to 16.5 dB.
• The system operates effectively with G.709 framing and enhanced FEC at a 10 dB OSNR.

Conclusions:

• The developed digital burst-mode optical receiver offers a large dynamic range and low overhead.
• The receiver's versatility makes it suitable for both synchronous and asynchronous dynamic network architectures.
• This technology supports burst timescales from nanoseconds to continuous data, enabling flexible optical network designs.