Monitoring and utilization of dispersive and nonlinear effects in high-speed reconfigurable WDM optical fiber networks

Chromatic dispersion and nonlinear effects are major issues on the physical layer of high-speed reconfigurable WDM optical network. For high performance and high capacity long-haul wavelength-division-multiplexing (WDM) optical transmission system, these effects become the limiting factors and need to be well managed, while at the same time, these effects can be utilized for different applications. In this Ph.D. dissertation, we present a detailed research on dispersive and nonlinear effects in high-speed optical network. We have demonstrated: (i) A dispersion monitoring technique by optically adding two in-band phase-modulated tones. No waveform distortion is observed and the sensitivity and monitoring range can be flexibly configured by choosing an appropriate combination of RF tones. (ii) CD and PMD monitoring in multi-level data modulation for both intensity and phase modulation in a 10-Gsymbol/s system. Careful consideration and characterization are necessary when we apply these monitoring techniques to the multi-level system. (iii) A novel technique to generate a supercontinuum of wavelength lines by phase and intensity modulating a standard CW single-frequency laser. We demonstrate a multi-wavelength source, with >130 channels, 10 GHz channel spacing and over 20 dB OSNR, without high power EDFA and short pulse laser. (iv) A wavelength-tunable all-optical wavelength conversion and wavelength multicasting technique using orthogonally polarized fiber FWM in highly-nonlinear dispersion shifted fiber. Nearly penalty free (<0.5 dB) transmission and a tuning range of 25-nm for both input and output signal wavelengths, are demonstrated in a 10Gb/s NRZ systems. (v) A continuously-tunable dispersionless 44-ns optical delay element using a two-pump periodically-poled lithium-niobate waveguide (PPLN), dispersion compensating fiber (DCF), and a fiber-Bragg-grating (FBG)-based dispersion compensator. A continuous optical delay up to 44-ns is demonstrated on a 10-Gb/s NRZ system. The wavelength of the output signal is the same as the input signal and this technique is not limited by the speed or modulation format of the signal.; These techniques will play key roles in future robust optical dynamic systems and reconfigurable networks.