A low noise amplifier for UWB and broadband applications is presented. The active dual loop negative feedback architecture dissevers the severe tradeoff existing between the input impedance, gain and noise figure, and produces a flat S11 across the entire band. The L#A is composed of a voltage amplifying negative feedback amplifier with a transconductance amplifier forming a shunt-shunt feedbac...

A structurally supportive miniaturized low-weight (≤150 g) radiofrequency switch mode amplifier developed to power the small diameter Pocket Rocket electrothermal plasma micro-thruster called MiniPR is tested in vacuum conditions representative of space to demonstrate its suitability for use on nano-satellites such as “CubeSats.” Argon plasma characterization is carried out by measuring the opt...

The stability margin of an audio power amplifier is reduced by a pole in the loopgain transfer function caused by shunt capacitance in the loudspeaker load. The problem is most severe in amplifiers with output stages that have a high output impedance before feedback. Because MOSFET devices can have an output impedance that is much higher than BJT devices, amplifiers with WFlT output stages are ...

Introduction Transmit array systems offer the promise of accelerated excitation, B1 shimming, and the potential for SAR and RF safety management [1,2], while also demanding high-fidelity RF playback in a challenging multi-channel environment. Tx coil arrays are subject to mutual coupling and loading variations, while RF power amplifiers exhibit non-linearity, ill-defined output impedances, and ...

In this paper, a high-efficiency and compact AlGaN/GaN heterojunction field-effect transistor (HFET) power amplifier integrated with a microstrip antenna at 7.25 GHz is presented for RF front-end circuit applications. A microstrip circular sector antenna is employed as both a radiator and frequency-dependent output load. Higher order harmonics from the HFET in nonlinear operation are reactively...

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...

This paper describes a CMOS rail-to-rail class AB operational amplifier designed to have extremely low output impedance and large current-drive capability. The amplifier uses an innovative output stage, having both source follower and common source stages working simultaneously throughout the output common-mode range. The source follower ensures low output impedance, which enables it to drive r...

In order to reduce the size of a wireless system, we propose a design theory for the broadband impedance matching circuit which connects an electrically small antenna (ESA) to a semiconductor amplifier. We confirmed its validity for the case of connection between a small slot loop antenna with a small radiation resistance of Ra = 0.776Ω and a semiconductor amplifier with high input impedance of...

In this paper a novel high performance all current-mode fully-differential (FD) Current mode Operational Amplifier (COA) in BIPOLAR technology is presented. The unique true current mode simple structure grants the proposed COA the largest yet reported unity gain frequency while providing low voltage low power operation. Benefiting from some novel ideas, it also exhibits high gain, high common m...

AbstractChopping is a proficient way to reduce the low frequency offset and 1/f noise in amplifiers. In this paper, a low power low noise CMOS chopper amplifier is presented. It is composed of a two stage amplifier. The first stage’s high output impedance and the equivalent Miller capacitance of the second stage constitute together a low pass filter, which reduces the power consumption. The cir...