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Coding Design for Fiber -Optic PolDM Systems. Chunpo Pan Supervisor: Prof. Frank Kschischang. Introduction. Fiber -Optic Communication. Cable TV Signal. Telephone Signal. On-off keying: spectral efficiency is only 0.8 b/s/Hz!. Internet Signal. Im. Im. Im. Re. Re. Re.
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Coding Design for Fiber-Optic PolDM Systems Chunpo Pan Supervisor: Prof. Frank Kschischang
Introduction Fiber-Optic Communication Cable TV Signal Telephone Signal On-off keying: spectral efficiency is only 0.8 b/s/Hz! Internet Signal
Im Im Im Re Re Re To Increase Spectral Efficiency • Noncoherent Detection to Coherent Detection • Polarization-Division Multiplexing (PolDM)
PolDM Systems in Literatures RZ-8PSK RZ-DQPSK CSRZ-DPSK RZ-DPSK
Impairments • Nonlinear impairments: Kerr nonlinearity • The higher the intensity, the greater the nonlinearity is • Will induce nonlinear phase noise (NLPN) • Linear impairments: Polarization mode dispersion (PMD) dominates!
PMD Fast axis Slow axis Time varying on the scale of milliseconds! Current compensators are complicated and expensive to build.
DPTC without PMD compensation H A unitary matrix! An analogue to wireless MIMO system Wireless System Differential Space-Time Coding (DSTC) PolDM System Differential Polarization-Time Coding (DPTC)
DPTC is a 2x2 unitary group.
Simulation Results Coherent PolDM-QPSK DPTC 64 points Optical PMDC Standard receiver Digital MLSE Electronic equalizer