Generation of (3, 1) vector signals based on optical carrier suppression without pre-coding

Area of Science:

• Optical communications
• Signal processing
• Photonics

Background:

• Traditional vector signal generation often requires complex pre-coding.
• Mach-Zehnder modulators (MZMs) are key components in optical modulation.
• Photodetectors exhibit square-law characteristics crucial for signal conversion.

Purpose of the Study:

• To demonstrate a simplified method for generating (3, 1) vector signals.
• To eliminate the necessity of pre-coding in vector signal generation.
• To evaluate the performance of the proposed scheme.

Main Methods:

• Experimental and numerical demonstration of (3, 1) vector signal generation.
• Utilizing a single Mach-Zehnder modulator (MZM) without pre-coding.
• Employing photodetector square-law conversion for signal modulation.

Main Results:

• Successful generation of a (3, 1) vector signal using a single MZM.
• Achieved consistent constellation distribution despite phase changes.
• Demonstrated superior bit-error-ratio (BER) performance compared to pre-coded signals.

Conclusions:

• The proposed scheme offers a simpler architecture for (3, 1) vector signal generation.
• The (3, 1) signal exhibits enhanced BER performance over 25 km optical fiber transmission.
• This method effectively bypasses the pre-coding step, simplifying optical communication systems.