Abstract—In this work, theoretical analysis and numerical results are given for time-reversal (TR) focus gains of polarization-varying electromagnetic fields in a rectangular resonant cavity. To demonstrate the gains in different polarization states of the static transceivers and the ones of the rotatable transceivers, the 3 dB attenuation areas of TR angle gain (AG) and AG flatness are first c...

We study theoretically and experimentally spectrally flat and broadband double-pumped fiber-optical parametric amplifiers (2P-FOPAs). Closed formulas are derived for the gain ripple in 2P-FOPAs as a function of the pump wavelength separation and power, and the fiber non-linearity and fourth order dispersion coefficients. The impact of longitudinal random variations of the zero dispersion wavele...

let $s$ be a monoid. in this paper, we prove every class of $s$-acts having a flatness property is closed underdirected colimits, it extends some known results. furthermore thisresult implies that every $s$-act has a flatness cover if and only if it has a flatness precover.

In this work, by means of numerical simulations, we verify that four-wave mixing (FWM) processes, including depletion and parametric gain, generate a redistribution of pump power in distributed fiber Raman amplifiers (DFRAs). As a consequence of pump-pump FWM, FWM products are generated, as well as a power exchange between pumps, which produces degradation in the performance of the amplifier du...

This paper presents an ultra-wideband (UWB) low noise amplifier (LNA) using two stage cascading topology to obtain high gain. Inductive degeneration and peaking inductor techniques are used to obtain wideband matching and flatness of gain. The proposed UWB LNA is implemented by using 180nm based CMOS TSMC technology using Advanced Design System (ADS) software.LNA achieves maximum gain of 15.5dB...

The OPA643 provides a level of speed and dynamic range previously unattainable in a monolithic op amp. Using a de-compensated voltage feedback architecture with two internal gain stages, the OPA643 achieves exceptionally low harmonic distortion over a wide frequency range. The "classic" differential input provides all the familiar benefits of precision op amps, such as bias current cancellation...

The objective of this paper is to investigate a ultra-wideband (UWB) low noise amplifier (LNA) by utilizing a two-stage cascade circuit schematic associated with inductive-series peaking technique, which can improve the bandwidth in the 3 10 GHz microwave monolithic integrated circuit (MMIC). The proposed UWB LNA amplifier was implemented with both co-planer waveguide (CPW) layout and 0.15 μm G...

A novel circuit topology for high-gain distributed amplifiers is presented in this study. Based on the conventional distributed architecture, the gain cells are realized by cascading cascode stages for gain enhancement. In addition, the stagger-tuning technique is extensively utilized in the design of the cascode stages as well as the cascaded stages, leading to significant improvement in terms...