In this field varactor diodes are used as a voltage variable capacitor in frequency multipliers, parametric amplifiers and variable junction when reverse biased which is the source of the capacitor effect.
12.
He was selected as member of Sigma Tau honorary engineering fraternity and became a member of BSEE degree Summa Cum Laude with an honors project to design and build a microwave parametric amplifier.
13.
The optical parametric amplifier has a wider bandwidth than a-amplifier, which in turn has a wider bandwidth than an optical parametric oscillator because of white-light generation even one octave wide.
14.
A full sized, four-sided MAR would require 25, 620 parametric amplifiers to be individually wired by hand, so building the smaller MAR-I greatly reduced cost and construction time.
15.
Both are well within the capability of modern electronic engineers ( I have designed and built parametric amplifiers myself, which proves it ! ), but in the early days of radio, it was of course the simpler techniques that got done first.
16.
Providing the high frequency AC power is a lot more expensive than providing DC . Parametric amplifiers have been used in specail applications requiring very low noise, and very high frequencies ( up into and past the visible light region ) where transistors won't work ( using gunn sources and lasers as the power source ), but for everything else, conventional DC powered transistor circuitry is a heck of a lot cheaper.
17.
To expand on that, it seems to me that the physics of'active'semiconductor devices ( like transistors vs .'passive'resistors ) usually " require " direct current ( rather than alternating ) to work . ( Keit60.230.203.147s'Parametric amplifiers being an exception . ) A basic transistor " cannot " work in AC to " directly " amplify an alternating current signal ).
