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Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
A comparison of modulation formats for passive optical networks
Domaniç Lavery1, Carsten Behrens, Seb J Savory
1Optical Networks Group, UCL Electronic & Electrical Engineering, Torrington Place, London, WC1E 7JE, United Kingdom. d.lavery@ee.ucl.ac.uk
Optics Express
|January 26, 2012
Summary
Polarization-switched quadrature phase shift keying (PS-QPSK) offers superior receiver sensitivity compared to other formats. This advanced modulation technique achieves an absolute sensitivity of -52.7 dBm (4.2 photons/bit) with preamplification.
Area of Science:
- Optical communication systems
- Digital modulation formats
- High-speed data transmission
Background:
- Receiver sensitivity is crucial for optical communication performance.
- Advanced modulation formats are needed to increase data rates.
- Preamplification can enhance signal detection.
Purpose of the Study:
- To compare the sensitivity of polarization-switched quadrature phase shift keying (PS-QPSK) with other formats.
- To evaluate the impact of preamplification on receiver sensitivity.
- To validate theoretical predictions of PS-QPSK performance.
Main Methods:
- Experimental comparison of PS-QPSK, PDM-QPSK, PDM-BPSK, and PDM-8QAM at 12.5 Gbit/s.
- Measurement of receiver sensitivity with and without signal preamplification.
- Utilizing hard decision forward error correction (FEC).
Main Results:
- PS-QPSK demonstrated a sensitivity advantage over PDM-QPSK, PDM-BPSK, and PDM-8QAM.
- Achieved an absolute sensitivity of -52.7 dBm (4.2 photons/bit) for PS-QPSK with preamplification.
- Results align with theoretical expectations for PS-QPSK performance.
Conclusions:
- PS-QPSK is a highly sensitive modulation format for optical communications.
- Preamplification significantly improves receiver sensitivity for PS-QPSK.
- PS-QPSK offers a promising solution for future high-speed optical networks.
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