New stop band 48 MHz crystal filter

Abstract

Band stop filter or band-rejection filter, with narrow attenuation characteristic is described in this paper. These filters do not pass signals within the cutoff frequencies. Аt the specific request of the customer, a crystal filter was realized, which operates at a frequency of 48MHz. When measuring the non-linearities of power amplifiers, a very narrow notch filter can be very useful to avoid the carrier frequency. Use of the filter may ensure that the maximum input power of a spectrum analyser used to detect spurious content will not be exceeded. Such filters are used in modern telecommunications for civilian and military purposes.