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4
Cavity Resonators
4.1 Introduction
In an ordinary electronic equipment, a resonant (or tuned) circuit consists
of an inductive coil and a capacitor, which are connected either in series
or in parallel. These circuits comprising lumped parameters L and C are
not without some resistance in the lower frequency range. The presence of
resistance in circuits results in losses and lowers their Q. Besides, in view of
the resonance frequency relation {f
0
= 1/2
π
√(LC)}, the requirement of L and
C becomes too small at high frequencies. This may include requirement of
lumped or distributed parameters. However, at higher frequencies, ...