The electronic layer multicast is going to face the speed and capacity bottleneck of the future optical data networks. Transparent optical wavelength multicast by multi-wavelength conversion is an effective way of achieving data multicast in the optical domain without any optical-electronic-optical conversion. In this paper, two multiple wavelength conversion technologies for 10 Gb/s data rate ...

A novel scheme is proposed to extend the sensing range of Brillouin optical time-domain analyzers (BOTDA). Specially-designed erbium doped fiber amplifier (EDFA) repeaters are located every 65km fiber along the sensing cable to achieve a total sensing length of 325km, corresponding to a 650km loop. At the end of the sensing fibre, we experimentally demonstrated a measurement repeatability of 2°...

A detailed experimental characterization of the transition process of an initially Gaussian pulse to the asymptotic self-similar parabolic solution in optical fibre amplifiers operating in the normal dispersion regime is performed.

The process of high-order harmonic generation leads to the production of a train of attosecond-duration extreme ultraviolet (XUV) pulses, with one pulse emitted per optical half-cycle. For attosecond pump-probe experiments, a single, isolated attosecond pulse is preferable, requiring an almost continuous spectrum. We show experimentally and numerically that the addition of a second laser field,...

We present a novel method for desiging multiwavelength pumped fiber Raman amplifiers with optimal gain-flatness and gain-bandwidth performance. We show that by solving the inverse amplifier design problem, relative gain flatness well below 1% can be achieved over bandwidths of up to 12 THz without any gain equalization devices. This constitutes a substantial improvement in gain flatness compare...

Determining if audio speaker limitations are violated can be challenging when using Class-D amplifiers. To obtain valid results, it is necessary to carefully analyze and interpret the switching behavior of the output signals . Filter-free Class-D amplifiers further complicate measurement because they do not require an output filter and the speaker can be connected directly to the amplifier outp...

This paper reviews the major contributions proposed in literature for implementing multi-band low noise amplifiers in CMOS technology. Concurrent, switched and switched concurrent low noise amplifiers are investigated. Advantages and drawbacks are also discussed. The article tries to offer good insights on the implementation of multi-band low noise amplifiers. Keywords-CMOS; low noise amplifier...

A number of current feedback operational amplifier topologies suitable for operation in a low-voltage environment are introduced in this paper. Their realization is based on the corresponding low-voltage second generation current conveyor topologies. Important performance factors such as accuracy, bandwidth, and linearity have been considered, and the obtained simulation results have been compa...

Vertical cavity semiconductor optical amplifiers (VCSOAs) are attractive devices for use in coherent optical amplification, especially where 2-D amplifier arrays are required. However, the coherence preservation quality of a VCSOA depends strongly on the bias condition, resonant wavelength mismatch, and the optical input power level. We characterize the coherence degree of a VCSOA as a function...

With the advancement of nanoscale semiconductor technology,semiconductor optical amplifiers are used to amplify and process all-optical signals. Inthis paper, with the aim of calculating the gain of quantum dot semiconductor opticalamplifier (QD-SOA), two groups of rate equations and the optical signal propagatingequation are used in the active layer of the device. For t...