MSc. Thesis Project
Carrier phase recovery for 8PSK coherent optical
fiber communication systems
Introduction
In nowadays high speed optical-fiber communication links, transmission of signals with
advanced modulation formats, e.g. 8-phase-shift-keying (8PSK), which have very high spectral
efficiency, is enabled by coherent detection technology. The transmitted data can be recovered
at a coherent receiver where impairments induced by fiber transmission, including chromatic
dispersion (CD), frequency and phase offset etc., are mitigated by digital signal processing (DSP)
algorithms. These DSP algorithms focusing the recovery of carrier frequency and phase are
dependent on the modulation formats that are used. Therefore, it is essential to perform a
detailed investigation to determine the optimum carrier phase recovery method for each
specific modulation format, which will be 8PSK in this project.
Project will be run in collaboration with Acreo Swedish ICT.
Contents
In this project, the student will firstly study and work on a VPI/MATLAB simulation model for
quadrature-PSK (QPSK) / 8PSK coherent transmissions, which have already been developed in
our previous works. Then the student will perform theoretical analysis and simulations on
mitigating the carrier offset and phase noise of the received signals. This thesis will be done in a
structured research framework where communication with other researchers is envisioned.
Requirements
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Lots of enthusiasm.
Courses on fiber-optic communications.
Fair knowledge in digital signal processing.
Experience in MATLAB/VPI simulations will be an advantage.
Applications
Applicants should contact:
Assoc. prof. Sergei Popov, KTH: sergeip@kth.se
Xiaodan Pang, Acreo Swedish ICT AB: xiaodan.pang@acreo.se