Traveling Wave Tubes (TWTs) consist of different elements. The most important element of TWT is the RF circuit. RF circuits in helix TWTs need a dielectric support to hold the helix; this support also has an effect in electromagnetic properties of RF circuits. A novel dielectric support is proposed to reduce the second harmonic of helix TWTs. The dielectric support in this structure consists of...

Traditional distributed amplification techniques have allowed for high gain and bandwidth at the expense of low efficiency. The decreased efficiency is primarily due to the existence of an actively loaded artificial transmission line as the output, resulting in backward wave propagation. Using the same traditional input line distributed techniques to achieve high bandwidth, this research has ex...

We describe a Nd:YAG slab laser master oscillator power amplifier (MOPA) system that has been scaled to 104 W of output power at 1064 nm, single transverse mode. The amplifier system consists of rod amplifiers followed by edgeand end-pumped slab amplifiers. The MOPA output of 104 W was 89% fundamental TEM00 spatial mode with less than 3% depolarization. These results are a key milestone in the ...

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...

The operation of the mammalian cochlea relies on a mechanical traveling wave that is actively boosted by electromechanical forces in sensory outer hair cells (OHCs). This active cochlear amplifier produces the impressive sensitivity and frequency resolution of mammalian hearing. The cochlear amplifier has inspired scientists since its discovery in the 1970s, and is still not well understood. To...

Traveling Wave Tube (TWT) amplifiers are high power, often broadband microwave amplifiers used extensively in satellite communications and electronic countermeasures. While the high-power outputs and wide gain-bandwidths make TWTs ideally suited for these purposes, the nonlinearity of these devices results in amplitude, phase and spectral distortion. Nonlinear distortion products appear as harm...

We report theoretical results on the wavelength stability of a multisection master-oscillator power-amplifier emitting at 1064 nm. use traveling wave equation model to calculate optical output power and spectral maps versus currents injected into different sections device. The numerical explains quantitatively experimental findings, particularly collapse if current control section adjacent dist...

We present a theoretical model and experimental characterization of microwave kinetic inductance traveling-wave (KIT) amplifier, whose noise performance, measured by shot-noise tunnel junction (SNTJ), approaches the quantum limit. Biased with dc current, this amplifier operates in three-wave mixing fashion, thereby reducing several orders magnitude power pump tone associated parasitic heating c...

For the past few years, we have been researching a novel type of photodetector featuring distributed optical amplification. We call these devices traveling-wave amplifier-photodetectors, or TAP detectors. The distributed combination of gain and absorption seeks a larger efficiency while keeping a low optical power, thus avoiding saturation. In this paper, we present experimental results both of...