An applications-oriented review of optical parametric amplifiers in fiber communications is presented. The emphasis is on parametric amplifiers in general and single pumped parametric amplifiers in particular. While a theoretical framework based on highly efficient four-photon mixing is provided, the focus is on the intriguing applications enabled by the parametric gain, such as all-optical sig...

The top shows current source amplifiers used with a loop array, the bottom shows ultra-low output impedance amplifiers used with a partially decoupled rung array. The current source amplifiers provide higher levels of decoupling, but are unable to generate as much current as the ultra-low output impedance amplifiers. 7333 A Comparison of Isolating Amplifier Architectures Neal Hollingsworth, Kat...

Gallium Nitride (GaN) amplifiers have demonstrated very high power density as well as wide band width in previous research. This paper examines their use in supplying flat gain, power, and linearity across a large band width. It demonstrates two types of power amplifiers: a Ft Doubler (FT2) amplifier and a Cascode amplifier, both of which require a simple PCB tune. Both amplifiers show 0.2 to 4...

The nullor is a theoretical two-port element suitable to model several multi-port devices common in audio circuitry, such as ideal operational amplifiers, transconductance and transistors operating linear regime. In this manuscript, we present an approach for the Wave Digital (WD) modeling implementation of circuits with multiple nullors. particular, propose compute scattering matrices WD topol...

Efficient RF power amplifiers used in third generation systems require linearization in order to reduce adjacent channel inter-modulation distortion, without sacrificing efficiency. Digital baseband predistortion is a highly cost-effective way to linearize power amplifiers (PAs). New communications services have created a demand for highly linear high power amplifiers (HPA's). Traveling Wave Tu...

Fujitsu has been developing gallium nitride high electron mobility transistors (GaNHEMT) for small transmitter amplifiers for Long Term Evolution (LTE) base stations. The use of GaN-HEMT in highly efficient transmitter amplifiers has attracted much attention because of its high breakdown voltage characteristics. High-efficiency amplifiers with high gain are needed to decrease the power consumpt...

A new non-linear method for design and analysis of solid state power amplifiers is presented and applied to an aluminum gallium nitride, gallium nitride (AlGaN-GaN) high electron-mobility transistor (HEMTs) on silicon-carbide (SiC) substrate for Ku band (12.4 13.6 GHz) applications. With combining output power of 8 transistors, maximum output power of 46.3 dBm (42.6 W), PAE of 43% and linear ga...