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Optical orthogonal frequency division multiplexing demultiplexer using slab star coupler-based optical discrete
Koichi Takiguchi1, Tsutomu Kitoh, Atsushi Mori
1NTT Photonics Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan. takiguchi.koichi@lab.ntt.co.jp
Optics Letters
|April 12, 2011
Summary
Researchers developed a compact optical demultiplexer using silica planar lightwave circuit technology. This device enables arbitrary subcarrier processing for high-speed optical orthogonal frequency division multiplexing (OFDM) signals.
Area of Science:
- Photonics
- Optical Communications
- Integrated Optics
Background:
- Optical orthogonal frequency division multiplexing (OFDM) is a key technology for high-capacity optical communication systems.
- Efficient and compact demultiplexing is crucial for realizing practical OFDM-based networks.
- Silica planar lightwave circuit (PLC) technology offers a robust platform for integrated optical devices.
Purpose of the Study:
- To demonstrate a novel optical demultiplexer for OFDM signals.
- To fabricate the device using silica PLC technology.
- To analyze the performance and limitations of the developed demultiplexer.
Main Methods:
- Fabrication of an optical discrete Fourier transform (DFT) circuit using silica PLC technology.
- Integration of the DFT circuit to create an optical OFDM demultiplexer.
- Experimental demonstration using a 100 Gbit/s (10 subcarrier × 10 Gbits/s) OFDM signal.
Main Results:
- Successful demonstration of a compact optical OFDM demultiplexer.
- The device can process an arbitrary number of subcarriers.
- A ten-channel device effectively demultiplexed a 100 Gbit/s OFDM signal.
- Key factors influencing device performance degradation were identified.
Conclusions:
- The developed silica PLC-based optical OFDM demultiplexer is a promising solution for future high-speed optical networks.
- The compact and arbitrary subcarrier processing capabilities offer significant advantages.
- Understanding performance degradation factors is essential for further optimization and reliability.
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