Spectrally efficient linear modulation techniques are used in the third generation systems and their performance is strongly dependent on the linearity of the transmission system, Also, the efficiency of the amplifier to be used has to be maximized, which means that it must work near saturation. Newer transmission formats, with wide bandwidths, such as multi carrier wideband code division multi...

The signal arrives from the antenna, and is amplified by one or more stages of RF amplification (and sometimes bandpass filterig), and is then presented to the 1 mixer where the signal is converted to a fixed intermediate frequency by the mixing action between the incoming signal frequency and the frequency produced by the Variable Frequency Oscillator. The result is a fixed intermediate freque...

A new approach for the electro-thermal modeling of LDMOSFETs for power-amplifier design that bypasses pulsed-IVs and pulsed-RF measurements is presented in this paper. The existence of low-frequency dispersion in LDMOSFETs is demonstrated by comparing pulsed IVs with iso-thermal IVs. The modeling technique uses iso-thermal IV and microwave measurements to obtain the temperature dependence of sm...

Abstract: The LInear amplification using Nonlinear Components (LINC) technique is a wellknown power amplifier linearization method to reduce adjacent channel interference in a nonconstant envelope modulation system. Its major drawback is the inherited sensitivity to gain and phase imbalances between the two amplifier branches. In this paper two novel adaptive fulldigital base band methods are d...

A Charge Recycling Sense Amplifier Based Logic is presented. This logic is derived from the Sense Amplifier Based Logic, which is a logic style with signal independent power consumption. It has been proven previously to protect security devices such as Smart Cards against power attacks. Experimental results show that the use of advanced circuit techniques, which enable charge recycling and inte...

This paper presents a Class-D power amplifier for bandpass pulse width modulated (BP-PWM) and bandpass deltasigma modulated (BP-DSM) signals at 20 MHz. A 1-bit 6-th order topology is used in the ∆Σ-modulator. Integral noise shaping is used in the generation of the bandpass pulse width modulated signal. A two sided pulse width modulation is used with a 6-bit 4th-order noise shaper. The push-pull...

In this study, a 1 W W-band solid-state power amplifier (SSPA) was developed for application in compact pulse Doppler radar. The SSPA up-converted the X-band signal to with multiplier (×8) and then amplified high output using an amplifier. To apply radar, which transmits receives signals single antenna, noise reduced by controlling drain voltage of according repetition frequencies. average obta...

Semiconductor Optical Amplifier (SOA) has attracted attention as a key component in supporting large capacity transmission systems. However, SOAs cause waveform distortion depending on the carrier lifetime, which ranges from picoseconds to nanoseconds, and this degrades signal quality. Thus, we are investigating suppressing by controlling gain characters time changing temperature of in-line opt...

in this paper first we try to analysis the behavior ofthe soas in the optical networks and then have proposed anumerical simple model to simulate the behavior of thesemiconductor optical amplifiers. after that by employing thismodel as inline amplifier for a dwdm optical system, we havesimulated the transmission of 10 channels with bit rate 10 gb/sup to distance 3970 km with rz-dpsk modulation ...

The design and development of a cryogenic Ultra-Low-Noise Signal Amplification (ULNA) and detection system for spectroscopy of ultra-cold systems are reported here for the operation in the 0.5 4 GHz spectrum of frequencies (the “L” and “S” microwave bands). The design is suitable for weak RF signal detection and spectroscopy from ultra-cold systems confined in cryogenic RF cavities, as entailed...