Intersymbol interference in DQPSK fibre-optic systems
Journal article, 2009

The limited bandwidth of high-speed transmitter and receiver hardware gives rise to intersymbol interference (ISI) in digital communication systems. The influence of such ISI is investigated in a low-complexity fiber-optical setting, using differential quaternary phase shift keying (DQPSK) modulation. The ISI is approximated by a memoryless, stochastic model, for use in applications where neither equalization nor sequence detection can be afforded. The channel capacity of this model is calculated and shown to depend strongly on the transmitter calibration. More than 3 dB is gained, at a target bit error rate of 10^(-6), by allowing the transmitted phase levels to deviate from their nominal multiples of pi/2 by up to 7 %.

Author

Hongxia Zhao

Chalmers, Signals and Systems, Communication, Antennas and Optical Networks

Erik Agrell

Chalmers, Signals and Systems, Communication, Antennas and Optical Networks

Magnus Karlsson

Chalmers, Microtechnology and Nanoscience (MC2), Photonics

European Transactions on Telecommunications

1124-318X (ISSN) 1541-8251 (eISSN)

Vol. 20 8 758-769

Subject Categories

Telecommunications

Signal Processing

DOI

10.1002/ett.1354

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7/3/2020 9