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Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
A WDM passive optical network enabling multicasting with color-free ONUs
Yue Tian1, Qingjiang Chang, Yikai Su
1State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of ElectronicEngineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Optics Express
|July 9, 2008
Summary
This study introduces a novel wavelength-division-multiplexing passive optical network (WDM-PON) for efficient unicast and multicast data transmission. The system enables source-free optical network units (ONUs) and supports simultaneous downstream and upstream communication.
Area of Science:
- Optical Communications
- Telecommunications Engineering
- Network Architecture
Background:
- Passive optical networks (PONs) are crucial for broadband access.
- Efficiently supporting both unicast and multicast services in PONs remains a challenge.
- Existing solutions often require complex architectures or compromise performance.
Purpose of the Study:
- To propose and demonstrate a novel WDM-PON architecture.
- To integrate downstream unicast and multicast services seamlessly.
- To enable source-free optical network units (ONUs) for reduced power consumption.
Main Methods:
- Utilizing a dual-drive Mach-Zehnder modulator (DDMZM) at the optical line terminal (OLT) for signal generation.
- Separating central carriers for multicast data and sub-carrier differential-phase-shift-keying (DPSK) signals for unicast traffic.
- Re-modulating downstream unicast signal power in ONUs for upstream transmission.
Main Results:
- Experimental demonstration of the proposed WDM-PON scheme.
- Successful transmission of 1.25-Gb/s downstream unicast data.
- Successful transmission of 1.25-Gb/s downstream multicast data.
- Successful transmission of 1.25-Gb/s upstream data, enabling source-free ONUs.
Conclusions:
- The proposed WDM-PON effectively integrates unicast and multicast services.
- The architecture supports efficient upstream transmission from source-free ONUs.
- This approach offers a promising solution for next-generation optical access networks.
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