Format:
1 Online-Ressource (XII, 330 p)
ISBN:
9783642679377
,
9783642679391
Series Statement:
Springer Series in Electrophysics 6
Note:
In this chapter, first the parametric principle is illustrated by two simple examples, one mechanical and one electrical. Then the realization of timevarying reactances is explained, followed by a short history of "parametric electronics". This survey demonstrates the importance of parametric circuits in the field of low-noise microwave electronics as well as explains the organization of this book. 1.1 The Parametric Principle An oscillating system comprising a single or several time-varying energystoring elements is called a parametric system; usually the variations are harmonic functions of time. Everybody knows one example of a mechanical parametric system from his childhood, namely, a swing. Therefore, we will start with this example though as it turns out, a swing is a rather complicated parametric system. Fortunately, the electrical parametric systems, which form the object of this book, are simpler. Figure 1.1 shows such a swing. If it is removed from its equilibrium position and the child stands on it in a fixed attitude, the swing oscillates with a certain amplitude, the magnitude of which decreases with time due to the mechanical friction of the system. To increase the amplitude of oscillation, the child changes positions during swinging: it crouches and straightens in a certain way twice during one cycle of the swing
Language:
English
Keywords:
Parametrische Schaltung
;
Einführung
DOI:
10.1007/978-3-642-67937-7
