Pulse shaping and its applications to optical communications

This thesis explores the concepts involved in building an acousto-optic modulator (AOM) pulse shaper, and discusses its applications in optical communications. It presents the results obtained using two AOMs with different rf center frequencies.; This work also discusses methods of pulse shaper characterization. It demonstrates a new interferometric method with an AOM pulse shaper, using spectrally dispersed ultrafast laser pulses and quadrature detection to measure optical thickness variations related to surface structure. Quadrature detection gives a larger dynamical range and solves the phase sign ambiguity problem. This method has potential applications for error compensation in pulse shaping, and in optical communications and device manufacture.; To create an ideal pulse shaper system, it is necessary to control both the amplitude and the phase of a pulse so that the amplitude shift keying (ASK), frequency shift keying (FSK) and phase shift keying (PSK) modulation can be realized. The research presented here shows the amplitude and the time domain control of an optical pulse in the pulse shaper. A numerical simulation was used to fit the spectral and nonlinear phase profile of a pulse after propagation through a dispersion shifted fiber.; Finally, a dense wavelength division multiplexed (DWDM) transmission was achieved, and a benchmark image was successfully transmitted over the communication channel. AOM-based pulse shaping can provide an alternative, low cost solution for spectrum sliced optical transmission.