A technique of laser pulse shaping was developed for low-emittance electron beam generation in a photocathode RF gun. The emittance growth due to space charge and RF effects in the RF gun was experimentally investigated with square and gaussian temporal laser pulse shapes. It is found that the square pulse shaping is a useful tool for both the reduction of nonlinear space charge force and the c...

In order to simplify the device of modulation and demodulation of 2FSK, a 2FSK modem based on the microcontroller AT89C51 was designed. This modem is mainly composed of an AT89C51 microcontroller, a simple two order passive low-pass filter, and a shaping circuit. Modulation is achieved on the basis of the principle of pulse width modulation (PWM). By executing PWM signal generating program, a d...

In this paper usingPredistortion technique for reducing distortion in the Videoconferencing channel. QPSK modulation is widely used technique in communication system whenever any data travelling through the channel it gets the AM/AM and AM/PM distortions .Predistortion is the technique in which if we know the channel response then We can create the inverse response of it and applying before the...

Time-multiplexed optical line-by-line pulse shaping with specific application to rapid update radio-frequency (RF) waveform generation is modeled. The effects of fundamental pulse shaping parameters on generated RF waveforms are numerically analyzed. Experimental and theoretical results are compared and are in excellent agreement.

We demonstrate efficient spectral compression of picosecond pulses in an all-fiber configuration at telecommunication wavelengths. Thanks to parabolic pulse shaping, a spectral compression by a factor 12 is achieved with an enhanced Strehl ratio. OCIS codes: 190.4370 (nonlinear optics, fibers), 320.5540 (pulse shaping), 070.4340 (optical signal processing)

A wavelet-based coder-decoder (codec) structure is defined for baseband waveform coding. Numerical results for bandwidth efficiency are given, and a comparison between several different wavelets is presented. Moreover, it is shown that wavelets obey the Nyquist pulse shaping condition and provide a unified framework for analog pulse shaping concepts of communications.

Spectral line-by-line shaping is a key enabler towards optical arbitrary waveform generation, which promises broad impact both in optical science and technology. In this paper, generation of optical and microwave arbitrary waveforms using the spectral line-by-line shaping technique is reviewed. Compared to conventional pulse shaping, significant new physics arises in the line-by-line regime, wh...

Multidimensional visible spectroscopy using pulse shaping to produce pulses with stable controllable phases and delays has emerged as an elegant tool to acquire electronic spectra faster and with greatly reduced instrumental and data processing errors. Recent migration of this approach using acousto-optic modulator (AOM) pulse shaping to the mid-infrared region has proved useful for acquiring t...

This paper presents a measurement circuit structure for capturing SET pulse-width suppressing pulse-width modulation and within-die process variation effects. For mitigating pulse-width modulation while maintaining area efficiency, the proposed circuit uses massively parallelized short inverter chains as a target circuit. Moreover, for each inverter chain on each die, pulse-width calibration is...

In the future, there will be a growing need for more flexible but efficient utilization of radio resources. Increased flexibility in radio transmission, however, yields a higher likelihood of interference owing to limited coordination among users. In this paper, we address the problem of flexible spectrum sharing where a wideband single carrier modulated signal is spectrally overlapped by unkno...