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Updated: Apr 22, 2026

Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping

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Published on: March 20, 2017

Pilot-based blind phase estimation for coherent optical OFDM system.

Xuebing Zhang, Jianping Li, Chao Li

|October 17, 2014

Summary

A novel pilot-based blind phase estimation method for coherent optical OFDM systems improves spectral efficiency. This technique achieves performance similar to conventional methods, enhancing phase noise compensation.

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Last Updated: Apr 22, 2026

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Quasi-light Storage for Optical Data Packets

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Published on: February 6, 2014

Area of Science:

Optical Communications
Signal Processing

Background:

Coherent optical orthogonal frequency-division multiplexing (CO-OFDM) systems face challenges with phase noise, impacting performance.
Conventional pilot-aided (PA) phase estimation methods consume valuable spectrum by inserting known pilot subcarriers.

Purpose of the Study:

To demonstrate a pilot-based blind (PBB) phase estimation method for CO-OFDM systems.
To improve spectral efficiency (SE) by reducing spectrum waste compared to PA methods.
To evaluate the phase noise compensation performance of the PBB method.

Main Methods:

A pilot-based blind (PBB) phase estimation technique was developed for CO-OFDM.
The PBB method replaces pilot subcarriers with specially designed unknown signals, avoiding the need for known pilot information.
Experiments involved 4-quadrature amplitude modulation (4-QAM) signals transmitted over 1760-km of standard single-mode fiber (SSMF) without dispersion compensation.

Main Results:

The proposed PBB method demonstrated effective phase noise compensation.
Spectral efficiency was improved due to the elimination of dedicated pilot subcarriers.
Experimental comparison showed the PBB method achieved performance comparable to the conventional PA method.

Conclusions:

The PBB phase estimation method is a viable alternative for CO-OFDM systems.
This method offers enhanced spectral efficiency without compromising phase noise compensation performance.
The PBB approach presents a promising solution for future high-capacity optical communication systems.