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Updated: May 15, 2026
09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
Combined utilization of partial-response coding and equalization for high-speed WDM-PON with centralized lightwaves.
1National ICT Australia, Level 2, Electrical and Electronic Engineering Department, University of Melbourne, Parkville, Victoria 3010, Australia. q.guo@pgrad.unimelb.edu.au
Optics Express
|December 25, 2012
Summary
This study enhances high-speed WDM-PON systems using partial-response (PR) signaling to overcome upstream transmission limits. The novel coding and equalization technique improves capacity and reach for next-generation access networks.
Area of Science:
- Optical Communications
- Telecommunications Engineering
- Signal Processing
Background:
- High-speed Wavelength-Division Multiplexing Passive Optical Networks (WDM-PON) face transmission impairments, particularly in the upstream direction.
- Low-bandwidth upstream transmitters, like 1-GHz Reflective Semiconductor Optical Amplifiers (RSOAs), limit system capacity and reach due to inter-symbol interference and reflection noise.
Purpose of the Study:
- To investigate and mitigate transmission impairments in a high-speed WDM-PON using a low-bandwidth upstream transmitter.
- To present a novel technique for enhancing spectral efficiency and extending transmission distance in the upstream link.
Main Methods:
- Employing a 1-GHz RSOA at 10 Gb/s and 20 Gb/s in a WDM-PON.
- Utilizing partial-response (PR) signal principles for coding and equalization.
- Optimizing the PR equalizer configuration for performance-complexity trade-off.
Main Results:
- Demonstrated support for 10 Gb/s upstream signals over 75-km and 20 Gb/s over 25-km bidirectional fiber.
- Achieved significant improvements in reflection tolerance: 8 dB for 10 Gb/s and 6 dB for 20 Gb/s channels with PR coding.
Conclusions:
- The proposed PR coding and equalization technique effectively overcomes upstream transmission limitations in WDM-PON.
- This cost-effective signal processing scheme offers significant potential for future access network development.
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