A high power wideband feedback amplifier module using AlGaN/GaN high electron mobility transistor (HEMT) has been developed that covers the frequency range of DC to 5GHz with small signal gain of 9 dB. Shunt feedback topology is introduced by adding inductances to increase the bandwidth. At midband frequency, power added efficiency (PAE) of 20 % and saturation power level of 29.5 dBm were obtai...

Amplifiers employing positive or negative feedback are fundamental building blocks in electronic circuits. Negative feedback is employed to linearize amplifiers in order to reduce distortion of the input signal and improve amplifier bandwidth. Conversely, applying sufficient positive feedback to an amplifier results in an oscillator because an output signal occurs when no input signal is presen...

a three-step selective photo-ionization for gd155 and gd157 isotopes by pulsed laser wasevaluated numerically. due to large thermal neutron absorption cross sections, these two isotopes innatural gadolinium are good candidates as burnable poison to control reactivity early in the fuel cycleand allow extended fuel burn up. rate equations have been used to calculate the dynamics of the isotopepop...

Public-address system has been widely used in many applications to amplify speech and music signals. In such environments, an acoustic feedback from a loudspeaker to a microphone usually exists and it may causes howling which explosively increases a certain frequency amplitude. The howling is a persistent and an annoying problem in many acoustic enviroments. To solve this problem, we have previ...

Comprehensive numerical simulations with the transmission-line laser model (TLLM) are used to compare the behavior of gain-coupled DFB lasers with index-coupled DFB lasers fabricated from identical materials. These simulations compare slope efficiency, threshold current, spectra, smallsignal modulation bandwidth, maximum-intrinsic modulation bandwidth, large-signal transient response and chirp,...

This paper describes a new feedback scheme suitable for block based video transmission as it is in use for H.261 video transmission over IP networks. The new scheme inherently provides support for highly unreliable communication links and thus improves packet switched video transmission over wireless links. The evaluation of the new feedback scheme has been done by means of a prototype implemen...

A high DC-gain low-power current recycling amplifier using positive-feedback technique is presented. In the proposed amplifier, the positive-feedback signal used to enhance the DC-gain is derived from the extra nodes created by cascoding. Positive-feedback offers the ability of obtaining a very high DC-gain, ideally infinite gain, without affecting high frequency performance and stability. Unde...