Abstract A new scheme of optical pulse generation using multiple optoelectronic phase locked loops is proposed. The principle of the scheme is combining three or more coherent optical waves having equal frequency separation. The coherencies of the optical waves are attained by the use of optoelectronic phase locked loops. The repetition frequency of the generated optical pulse is equal to the f...

We present measurements on terahertz generation by optical rectification, in which both the thickness of the generation crystal and the wavelength of the generating optical pulse are varied. The difference between the group velocity at optical frequencies and the phase velocity at terahertz frequencies affects the time trace and spectrum of the generated terahertz pulse. For the thickest crysta...

introduction blood pressure (bp) is one of the important vital signs that need to be monitored for personal healthcare. arterial blood pressure is estimated from pulse transit time (ptt). this study uses two pulse sensors to get ptt. the aim of this study was to construct an optical system and to monitor blood pressure continuously and without cuff in people with different ages. materials and m...

This paper presents recent results in the development of novel ultrafast technologies based on the generation and application of extremely chirped optical pulses. Linearly frequency-swept modelocked optical pulses of ns durations are generated, at the infrared telecommunications wavelength of 1.55 mm, by using chirped fiber Bragg gratings. The swept pulses appear as continuous wave signals, whi...

Gain-switched laser diodes are widely used to generate short optical pulses, which ®nd several applications in optical ®ber measurements and high-speed optical communication systems. Temporal and spectral properties of the gain-switched pulses can be tailored by ®ltering their optical spectrum. Optical ®ltering leads to suppression of frequency chirp and generation of transform-limited pulses. ...

A novel approach to photonic generation of phase-coded microwave signals based on optical pulse shaping and time delay is proposed. In the proposed approach, an optical short pulse train is inserted with a specified amount of time-delay to certain pulses, and then converted into super-Gaussian microwave pulses based on the optical pulse shaping technique. By properly adjusting the time-delay, p...

Due to the growing demand for higher bandwidth, employing optical devices instead of electronic devices in data transmission systems has attracted much attention in recent years. Optical switches, modulators and wavelength converters are a few examples of the required optical devices. CMOS compatible fabrication of these devices, leads to much more growing of this technology. Optical pulse comp...

Spectrum efficient data transmission is of key interest for high capacity optical communication systems considering the limited available bandwidth. Transmission of the high speed signal with higher-order modulation formats within the Nyquist bandwidth using coherent detection brings attractive performance advantages. However, high speed Nyquist signal generation with high order modulation form...

The generation of pulses in dual-pump fiber optical parametric amplifier is investigated. Theoretically, it is shown that in an analogical manner to pulse generation in single-pump fiber optical parametric amplifiers, the generated pulse shape depends on the linear phase mismatch between the interacting waves. However the dual-pump architecture allows for the bounding of the phase mismatch over...