256 Tbit/s/ch polarization-multiplexed DQPSK transmission over 300 km using time-domain optical Fourier transformation

Abstract

We demonstrate a 2.56 Tbit/s/ch polarization-multiplexed single-carrier transmission over 300 km using subpicosecond DQPSK signals. We adopted an ultrafast time-domain optical Fourier transformation technique to reduce waveform distortions. For such an ultrashort optical pulse, depolarization components resulting from second-order polarization-mode dispersion (PMD) become a dominant factor as regards signal distortion because of the broad signal bandwidth. The influence of inter-polarization crosstalk induced by second-order PMD, is presented in detail.

All-optical OFDM demultiplexing with optical partial Fourier transform and coherent sampling

“…Optical time-lenses are capable of ultra-high-speed Fourier transformation of multiple channels [12]. Recently, two AO-OFDM demultiplexing schemes based on time-lenses were proposed by Palushani [9] and Guan [13].…”

80-GB all-optical serial-to-parallel convertor for QPSK signal based on cascaded phase modulators and optical f ilters

“…With its advantages of compact structure, high speed, low power penalty, simultaneous two-tributary operation, and no assistance from a light source, the SPC has potential for use in future OTDM networks. However, the performance of the SPC still needs improvement.OCIS codes: 320.7080, 320.1590, 060.5060. doi: 10.3788/COL201210.113201.The optical time-division multiplexing (OTDM) technique is seen as a very attractive candidate for increasing the bit-rate per wavelength channel further [1] . An all-optical serial-to-parallel converter (SPC) with multitributary demultiplexing capability and low power consumption is a key technique for OTDM networks.…”

“…Other reported demultiplexers, including those based on either electro-optical on-off gates utilizing electro-absorption modulator (EAM) [2] , phase modulator (PM) [3] , Mach-Zehnder modulator (MZM) [4] , and nonlinear effects, such as cross-phase modulation (XPM) [5] and four-wave mixing (FWM), are also incapable of multi-channel processing [6] . Thus, along with the application of multi-level modulation formats, such as differential quadrature phase-shift keying (DQPSK) in OTDM systems [1,7] , the development and investigation of schemes that are capable of demultiplexing, such OTDM signals with phase-preserving and multi-tributary processing capabilities, are necessary.In this letter, an all-optical SPC that uses two cascaded PMs and optical band-pass filters (OBPFs) is experimentally investigated for optical quadrature phase-shift keying (QPSK) signals. We demonstrate the application of the SPC for the simultaneous demultiplexing of two 40-GB base-rate OTDM tributaries from an 80-GB OTDM RZ-DQPSK signal.…”

“…The optical time-division multiplexing (OTDM) technique is seen as a very attractive candidate for increasing the bit-rate per wavelength channel further [1] . An all-optical serial-to-parallel converter (SPC) with multitributary demultiplexing capability and low power consumption is a key technique for OTDM networks.…”