In modern transmitting devices the digital predistortion technique is widely used for linearizing the power amplifier. There are many algorithms realizing predistortion technique with a different complexity and a stability of results. The several methods are described and compared. The orthogonal polynomials with memory were has proved to be simple enough with suitable results, so it was chosen...

A master oscillator power amplifier (MOPA) with variable amplifier gain lengths was built to demonstrate power enhancement of an alkali vapor laser. A small signal gain of 0.91 / cm for two different gain lengths was observed. For a 2 cm long amplifier gain length an amplification of 7.9 dB was observed.

In RFID reader systems, power amplifier plays a critical rule for efficiency enhancement. A high efficiency power amplifier may not only increase the life expectancy of portable RFID devices but also reduce the reliance on heat sinks. Heat sinks usually occupy plenty of space and lead to packing difficulties. A well-designed power amplifier with high efficiency and output power may also increas...

The existing UHF Satellite Communications (SATCOM) transponders used for military applications use efficient, saturated power amplifiers, which provide one earth-coverage antenna beam. The amplifier is dedicated to small frequency band and only handles a few carriers simultaneously. The communications capacity needed to support future military forces on the move will require satellite payload p...

We investigate the energy optimization (minimization) for amplified links. We show that using the using a well-established analytic nonlinear signal-to-noise ratio noise model that for a simple amplifier model there are very clear, fiber independent, amplifier gains which minimize the total energy requirement. With a generalized amplifier model we establish the spacing for the optimum power per...

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...

This paper reports the design, optimization, and test results of a mechanical amplifier coupled to an electromagnetic energy harvester to generate power from lowamplitude (±1 mm) and low-frequency (<5 Hz) vibrations in the presence of large static displacements. When coupled to a translational kinetic energy harvester, the amplifier boosts small vibration amplitudes by as much as 4x while accom...

This paper examines different linearization techniques which are used to linearize the power amplifier by emphasizing on weakness and strength of each technique. After complete analyze it has been concluded that Digital Pre Distortion (DPD) technique is the best linearization technique to linearize the power amplifier. DPD technique for linearizing a wideband radio frequency power amplifier has...

Wide frequency bandwidth has been internationally allocated for unlicensed operation around the oxygen absorption frequency at 60 GHz. A power amplifier and a low noise amplifier are presented as building blocks for a T/R-unit at this frequency. The fabrication technology was a commercially available 0.15 μm gallium arsenide (GaAs) process featuring pseudomorphic high electron mobility transist...