Now-a-days leakage power is an important issue in microprocessor’s and hardware’s. In modern computer systems memory components covers 70 to 80 percent of total area of microprocessors that means memory contains more number of transistors. Generally leakage power dissipation proportional to the number of transistors. So the leakage power dissipation is more in the memories. In high performance ...

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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...

Power amplifiers (PAs) are inherently nonlinear elements and digital predistortion is a highly cost-effective approach to linearize them. Although most existing architectures assume that the PA has a memoryless nonlinearity, memory effects of the PAs in many applications ,such as wideband code-division multiple access (WCDMA) or orthogonal frequency-division multiplexing (OFDM), can no longer b...

Radio frequency power amplifiers play a key role in transceivers for mobile communications and their linearity is a crucial aspect. In order to meet the linearity requirements dictated by the standard at a reasonable efficiency, the usage of a linearization technique is desired. For effective implementation of any linearization technique, accurate modelling of power amplifier is required. Due t...

We generate linearly polarized, 287 W average-power, 5.5 ps pulses using a cryogenically cooled Yb:YAG amplifier at a repetition rate of 78 MHz. An optical-to-optical efficiency of 41% is obtained at 700 W pump power. A 6 W, 0.4 nm bandwidth picosecond seed source at 1029 nm wavelength is constructed using a chirped-pulse fiber amplification chain based on chirped volume Bragg gratings. The com...

The new generation mobile communication systems are very sensitive to the nonlinearities in their transmitting paths. The power amplifier is a key component which generates the nonlinear distortions. Power amplifier linearization techniques are very important to reduce the distortion of the transmitted signal and the adjacent band interference of users. As its facility of implementation, adapti...