TY  - RPRT
A1  - Basiana, Ariadna Farres
A1  - Martinsson, Hanna
A1  - Vik, Brage Ofstad
A1  - Pereverzyev, Sergiy
A1  - Purrucker, Martin
A1  - Schmitz Abe, Klaus Erich
A1  - Stiel, David
A1  - Strautins, Uldis
T1  - Frequency Filtering in Telecommunications
N2  - Piezoelectric filters are used in telecommunication to filter electrical signals. This report deals with the problem of calculating passing and damped frequency intervals for a filter with given geometrical configurations and materials. Only periodic filters, which are widely used in practice, were considered. These filters consist of periodically arranged cells. For a small amount of cells a numerical procedure to visualise the wave propagation in the filter was developed. For a big number of cells another model of the filter was obtained. In this model it is assumed that the filter occupies an infinite domain. This leads to a differential equation, with periodic coefficients, that describes propagation of the wave with a given frequency in the filter. To analyse this equation the Spectral Theory for Periodic Operators had to be employed. Different ways -- analytical and numerical -- to apply the theory were proposed and analysed.
KW  - eigenvalue problems
KW  - piezoelectric periodic surface acoustic wave filters
KW  - SAW filters
KW  - wave propagation
Y1  - 2004
UR  - https://kluedo.ub.uni-kl.de/frontdoor/index/index/docId/1625
UR  - https://nbn-resolving.org/urn:nbn:de:hbz:386-kluedo-16259
ER  -