Polarization modulation in ultra-long haul transmission systems: a promising alternative to intensity modulation

Proposal and Performance Evaluation of a Hetetodyne 8-PolSK Optical Transmission System

“…After the EDFA and WDM techniques came, interest in coherent systems decreased. In current systems, the need for constant power multilevel modulation formats (for combating non-linear effects and achieving large bit rates) has renewed the interest in PolSK [6][7][8][9]. When compared with other multilevel constant power modulation formats, it has been shown [1] that M-PolSK outperforms M-DPSK (Differential Phase Shift Keying) when the number of levels M increases.…”

Different Modulation Formats Used In Optical Communication System

“…A differential polarization-phase shift keying(DPolPSK) system is introduced. [6] In this system information is encoded in both polarization and phase with multilevel direct detection. In this system the effect of nonlinear polarization scattering is reduced.…”

Improvement of SPM nonlinear limit by chirped duobinary PolSK transmission

“…The main advantages of PolSK over intensity modulation and direct detection (IM-DD) are its constant power envelope, and thus a reduced sensitivity to SPM and cross-phase modulation (XPM), a 3dB better sensitivity in terms of peak power, the feasibility of bandwidth and power efficient in multilevel systems 4,5,6 .…”