In recent time, the demand for Darlington pair amplifier for high data rate communication system has been appreciated and highlighted. The application of Darlington pair amplifier is supported in a condition, where requirement of high gain at a low frequency is applicable. Recently, Darlington pair amplifier has been testified with high gain bandwidth product for current applications. If we nee...

In several reports issued previously, a theoretical analysis has been given for the steady-state operation of a vacuum-tube power amplifier with a complex load impedance* This theoretical work was checked experimentally with amplifiers operating in the steady state at low power levels. One application of an amplifier which sometimes must operate with a complex load impedance is in naval sonar e...

Raman amplification of a 49 cm Bismuth oxide (Bi2O3) as a nonlinear gainmedium based erbium doped fiber amplifier (EDFA) is reported in new and compactdesign in near infrared spectral regions. The bismuth glass host provides theopportunity to be doped heavily with erbium ions to allow a compact optical gain fiberamplifier design by using reduced fiber length and the 1480...

Introduction The need for highly efficient, linear microwave power amplifiers has grown rapidly, especially as mobile and satellite communication systems have been developed and expanded [1]. These systems employ multilevel digital modulation techniques to achieve higher-data-rate and multimedia services. This results in a band-limited multi-carrier signal, which is spectrally efficient but exh...

We have constructed a dc-coupled differential amplifier capable of operating in the 4.2 K – 300 K temperature range. The amplifier can be operated at high-bias setting, where it dissipates 5 mW, has noise temperature TN < 0.8 K at 4 k source resistance and >40 MHz bandwidth at 4.2 K bath temperature. The bias setting can be adjusted: at our lowest tested setting the amplifier dissipates <100 W,...

We describe a Nd:YAG slab laser master oscillator power amplifier (MOPA) system that has been scaled to 104 W of output power at 1064 nm, single transverse mode. The amplifier system consists of rod amplifiers followed by edgeand end-pumped slab amplifiers. The MOPA output of 104 W was 89% fundamental TEM00 spatial mode with less than 3% depolarization. These results are a key milestone in the ...

Quantum amplifier channels are at the core of several physical processes in nature. Not only do they model the optical process of spontaneous parametric down-conversion, but the Bogoliubov transformation corresponding to an amplifier channel also describes the physics of the dynamical Casimir effect in superconducting circuits, the Unruh effect, and Hawking radiation. Here we study the communic...

In this paper, we analyze a distributed amplifier based on input/output attenuation compensation. The analysis is carried out for a HEMT transistor; and a constant-k section filter is used to calculate the amplifier’s characteristics such as attenuation factor, phase constant and gain. The proposed design approach enables us to examine the tradeoff among the variables, which include the type an...

approved: Andreas Weisshaar In cellular telephones, RF power amplifiers consume a significant part of the total phone current. Reducing the average PA current will extend battery life. In GSM systems the handset is commanded by the base station to transmit at power levels lower than full power much of the time. A Doherty amplifier can be used to improve efficiency at these lower power levels, p...