Optical arbitrary waveform generation using the line-by-line pulse shaping technique has been shown to be sensitive to variations in the offset frequency of the input frequency comb due to time-domain waveform interference. Here we present a frequency-domain model that is able to predict waveform changes arising from offset frequency variations. In experiments we controllably shift the frequenc...

In this work performance of Gaussian Minimum Shift Keying (GMSK) modulation is compared with that of conventional QPSK and M-QAM modulation schemes. Use of unfiltered data stream for modulation results in a considerably large bandwidth in the modulated RF signal. Pulse shaping as a signal processing technique has gain grounds as a means to mitigate this problem. Gaussian filter along with squar...

Pulse shaping is utilized to increase transmission data rate without increasing the bandwidth or bit error rate. In this paper an efficient approach is presented to design and implement a high speed Gaussian pulse shaping filter for ISI removal. The proposed filter has been designed and simulated using Matlab, synthesized with Xilinx Synthesis Tool (XST), and implemented on Spartan 3E based 3s5...

In this paper the method of sensorless startup of direct current brushless motor using third harmonic back Electromotive Force (EMF) and motor startup using microcontroller for pulse width modulation, power switch control and motor output analysis is presented which renders RPM control and high speed achievement for motor. The microcontroller is used for processor and MOSFETs are used for power...

A multiple-circuit high pulse repetition frequency (PRF) pulse generator for the pumping of rare gas halide lasers is reported. With this multiple-circuit design, high PRF can be achieved by the use of existing low PRF thyratron switches and capacitors. A two-circuit pulse generator was constructed, and its performance is described. By means of this pulse generator and a blowdown-type fast tran...

This article presents a new circuit to generate a higherorder derivative Gaussian pulse for the impulse radio ultra-wideband (IR-UWB) communication systems. This IR-UWB pulse generator is designed and measured with the TSMC 0.18m CMOS process. The circuit is able to generate a symmetrical and low-ringing pulse in a frequency band from 3.1 to 10.6 GHz. Our work shows that the pulse generator’s o...

The experiments in this thesis have been performed using femtosecond laser pulses at different wavelengths. The second and third harmonic of of the fundamental output (800 nm) of a commercial laser have been used in several experiments. In other experiments laser pulses in the visible were required. A homebuilt non-collinear optical parametric amplifier (NOPA) has been used to generate tunable ...

Techniques for the precise synthesis and control of the temporal shape of optical pulses with durations in the picosecond and sub-picosecond regimes have become increasingly important for a wide range of applications in such diverse fields as ultrahigh-bit-rate optical communications (Parmigiani et al., 2006; Petropoulos et al., 2001; Oxenlowe et al., 2007; Otani et al., 2000), nonlinear optics...

Extremum seeking, a non-model based optimization scheme, is employed to design laser pulse shapes that maximize the amount of stored energy extracted from the amplifier gain medium for a fixed input energy and inversion density. For this pulse shaping problem, a double-pass laser amplifier whose dynamics are fully coupled and composed of two nonlinear, first-order hyperbolic partial differentia...