Development and real-time implementation of digital signal processing algorithms for coherent optical receivers / Timo Pfau. 2009
Inhalt
- Abstract
- Zusammenfassung
- Publications
- Table of contents
- Glossary
- 1 Introduction
- 2 Fundamentals
- 2.1 M-ary quadrature amplitude modulation
- 2.1.1 QAM constellations with equidistant-phases
- 2.1.2 Square QAM constellations
- 2.1.3 Differential encoding and decoding
- 2.2 Coherent optical QAM transmission system
- 2.2.1 Optical QAM transmitter
- 2.2.2 Polarization-multiplexed QAM transmitter
- 2.2.3 Optical transmission link impairments
- 2.2.3.1 Attenuation
- 2.2.3.2 Polarization crosstalk & polarization-dependent loss
- 2.2.3.3 Chromatic dispersion
- 2.2.3.4 Polarization mode dispersion
- 2.2.3.5 Amplified spontaneous emission
- 2.2.4 Coherent optical QAM receiver with digital signal processing
- 3 Digital signal processing algorithms for coherent optical receivers
- 3.1 Constraints for algorithms in digital receivers for coherent optical communication
- 3.1.1 Feasibility of parallel processing
- 3.1.2 Hardware efficiency
- 3.1.3 Tolerance against feedback delays
- 3.2 Clock recovery
- 3.3 Polarization control & equalization
- 3.3.1 Non-data-aided polarization control
- 3.3.2 Decision-directed polarization control
- 3.3.3 Decision-directed ISI compensation
- 3.4 Feed-forward carrier recovery
- 3.4.1 Viterbi & Viterbi algorithm
- 3.4.2 Weighted Viterbi & Viterbi algorithm
- 3.4.3 Barycenter algorithm
- 3.4.4 Feed-forward carrier recovery for arbitrary QAM constellations
- 3.4.4.1 Square QAM constellations
- 3.4.4.2 Arbitrary QAM constellations
- 3.4.4.3 Hardware-efficient implementation
- 3.4.5 Hardware effort
- 3.5 Data recovery
- 3.5.1 Data recovery for QAM constellations with equidistant-phases
- 3.5.2 Data recovery for square QAM constellations
- 3.6 Intermediate frequency control
- 4 Simulation results
- 4.1 QPSK carrier recovery
- 4.1.1 QPSK carrier phase estimator efficiency and mean squared error
- 4.1.1.1 Carrier phase estimator efficiency for Δf·TS = 0
- 4.1.1.2 Carrier phase estimator mean squared error for Δf·TS > 0
- 4.1.2 QPSK phase noise tolerance
- 4.1.2.1 Viterbi & Viterbi algorithm performance
- 4.1.2.2 (S)MLPA algorithm performance
- 4.1.2.3 4-QAM carrier recovery performance
- 4.1.2.4 Summary
- 4.1.2.5 Common carrier in a polarization-multiplexed QPSK receiver
- 4.1.3 QPSK analog-to-digital converter resolution
- 4.1.4 QPSK phase resolution
- 4.2 QAM carrier recovery
- 4.2.1 Square QAM phase angle resolution
- 4.2.2 Square QAM phase estimator efficiency
- 4.2.3 Square QAM phase noise tolerance
- 4.2.4 Square QAM analog-to-digital converter resolution
- 4.2.5 Square QAM internal resolutions
- 4.3 Polarization control and PMD compensation
- 5 Implementation of a synchronous optical QPSK transmission system with real-time coherent digital receiver
- 5.1 Single-polarization synchronous QPSK transmission with real-time FPGA-based coherent receiver
- 5.1.1 Single-polarization synchronous QPSK transmission setup
- 5.1.1.1 QPSK transmitter
- 5.1.1.2 Coherent optical receiver frontend
- 5.1.1.3 FPGA-based digital signal processing
- 5.1.2 Self-homodyne experiment results at 800 Mb/s
- 5.1.3 Intradyne experiment results at 800 Mb/s
- 5.1.4 Intradyne experiment results at 1.6 Gb/s
- 5.1.5 System optimizations & comparison of 90° hybrid with 3x3 coupler
- 5.1.6 Comparison of experimental with simulation results
- 5.2 Polarization-multiplexed synchronous QPSK transmission with real-time FPGA-based coherent receiver
- 5.2.1 Polarization-multiplexed QPSK transmission setup
- 5.2.1.1 Pattern generator and QPSK precoder
- 5.2.1.2 QPSK transmitter
- 5.2.1.3 Ultra-fast polarization scrambler
- 5.2.1.4 Polarization diversity coherent optical receiver frontend
- 5.2.1.5 FPGA-based digital signal processing
- 5.2.2 Influence of different carrier recovery filter widths
- 5.2.3 Polarization tracking capability
- 5.2.4 Polarization tracking capability with optimized VHDL code
- 5.2.5 Influence of PDL on the receiver sensitivity
- 5.3 Polarization-multiplexed synchronous QPSK transmission with real-time ASIC based coherent receiver
- 6 Discussion
- 7 Summary
- 8 Outlook
- 9 Bibliography
- 10 List of figures & tables
- Acknowledgement