Establishment of an Electro-Optical Mixing Design on a Photonic SOA-MZI Using a Differential Modulation Arrangement

Area of Science:

• Photonics and Optical Communications
• Semiconductor Devices
• Signal Processing

Background:

• Advanced optical communication systems require efficient methods for signal mixing and frequency up-conversion.
• Semiconductor optical amplifier Mach-Zehnder interferometers (SOA-MZI) offer potential for high-performance electro-optical signal processing.

Purpose of the Study:

• To design and evaluate experimental systems for single and simultaneous electro-optical SOA-MZI mixing.
• To optimize optical and electrical performance for high-frequency applications.
• To assess the performance of 128-quadratic amplitude modulation (128-QAM) signals after up-mixing.

Main Methods:

• Utilized a differential modulation mode with an optical pulse source (OPS) at 39 GHz and 1 ps pulse width.
• Implemented SOA-MZI based systems for electro-optical mixing.
• Evaluated electrical conversion gains (ECGs) and error vector magnitudes (EVMs) for 128-QAM signals.

Main Results:

• Achieved passive power stability better than 0.3% RMS over one hour.
• Generated up to 22 dBm average output power with 32 dB optical conversion gain.
• Obtained a record output optical signal-to-noise ratio (OSNR) up to 77 dB.
• Demonstrated SOA-MZI mixing up to 118.5 GHz with consistent conversion gains.
• Achieved 6% EVM at 10 GSymb/s symbol rate within the 118.5 GHz frequency range.
• Reached a peak data rate of 70 GBit/s for the 128-QAM up-mixed signal.

Conclusions:

• The developed SOA-MZI mixing systems exhibit excellent performance, including high power stability and record OSNR.
• The systems enable efficient up-mixing of 128-QAM signals to high frequencies with good signal quality.
• The simultaneous electro-optical mixing system shows significant performance improvements for future optical communication applications.