During the past year, our principal activity in this area was concerned with the development of a small-signal theory for the behavior of stagger-tuned klystron amplifiers, and the construction of an experimental seven-cavity amplifier. In the coming year, we shall continue the work on the experimental tube, in order to get experimental verification of the theory. The limiting gain-bandwidth pe...

The use of so-called “composite left/right-handed transmission lines” in the design of distributed amplifiers is discussed using a simple model for the active device. The simplified analysis performed herein shows that it is possible to modify the frequency response of forward and reverse power gains, a significant development which could lead to innovative distributed amplifier designs. © 2006...

We describe a new kind of phase-preserving quantum amplifier which utilizes dissipative interactions in a parametrically coupled three-mode bosonic system. The use of dissipative interactions provides a fundamental advantage over standard cavity-based parametric amplifiers: large photon number gains are possible with quantum-limited added noise, with no limitation on the gain-bandwidth product....

All-fiber multiwavelength lasers have attracted much interest recently because of their potential applications in wavelength-division-multiplexing (WDM) communications, microwave generation, highresolution spectroscopy, fiber optic sensing, etc. This paper is devoted to these lasers and several of their aspects, as the laser design, the output power fluctuations, or different kinds of lasers, h...

The peak-to-average ratio (PAR) of a signal is commonly used for estimating the backoff required for an radio-frequency/microwave power amplifier to exhibit acceptable intermodulation distortion. In this paper, it is shown that the PAR is an inaccurate metric for predicting the backoff and can lead to improper choices for modulation with respect to the linearity–efficiency tradeoff. A specific ...

This paper presents a broadband GaN pseudo high-electron-mobility transistor (pHEMT) two-stage driver amplifier based on an enhanced feedback technique for wideband system. Through well-designed parameter values of the and matching structure circuit, relatively flat frequency response was obtained over wide band. Simultaneously, in order to reduce fluctuation current caused by environmental tem...

Power-amplifier efficiency is a significant issue for the overall efficiency of most wireless system. Therefore, currently there are different kind of Switched mode power amplifiers are developed which are showing very high efficiency also at higher frequencies but all of these amplifiers are subjected to drive with the constant envelope signals. Whereas, for the increasing demand of high data ...

An ultra low power consuming low noise amplifier (LNA) at C-band with variable gain for adaptive antenna combining is presented in this paper. The microwave monolithic integrated circuit (MMIC) was fabricated using commercial 0.25 μm bipolar complementary metal oxide semiconductor (BiCMOS) technology. At 5.2 GHz, a supply voltage of 1.2 V and a current consumption of only 1 mA, a maximum gain o...