Related Experiment Video
Updated: May 25, 2026
07:45
Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
Demonstration of asynchronous, 40 Gbps x 4-user DPSK-OCDMA transmission using a multi-port encoder/decoder.
Nobuyuki Kataoka1, Gabriella Cincotti, Naoya Wada
1National Institute of Information and Communications Technology (NICT), 4-2-1 Nukui-Kitamachi, Koganei, Tokyo 184-8795, Japan.
Optics Express
|January 26, 2012
Summary
A new 8-chip encoder/decoder was developed for 40 Gigabit per second Passive Optical Networks (PON). This device successfully multiplexed four users and demonstrated 50 km transmission for the first time.
Area of Science:
- Optoelectronics
- Telecommunications Engineering
Background:
- Passive Optical Networks (PON) are crucial for high-speed internet delivery.
- Existing encoder/decoder technologies face limitations in multiplexing capacity and transmission distance.
Purpose of the Study:
- To develop a novel encoder/decoder for enhanced performance in 40 Gb/s PON systems.
- To demonstrate the multiplexing of multiple asynchronous users and long-distance transmission capabilities.
Main Methods:
- Development of an 8-chip encoder/decoder architecture.
- Implementation of Differential Phase-Shift Keying (DPSK) modulation.
- Integration of eight input/output ports for versatile connectivity.
Main Results:
- Achieved a total processing speed of 320 Gchip/s.
- Successfully multiplexed four asynchronous 40 Gb/s users.
- Demonstrated reliable data transmission over a 50 km fiber optic link for the first time.
Conclusions:
- The new encoder/decoder significantly advances 40 Gb/s PON capabilities.
- The device offers a robust solution for increasing network capacity and reach.
- This technology paves the way for next-generation high-speed optical communication networks.
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