FILTER ZUR UNTERDRUECKUNG VON OBERFLAECHEN-INTERFERENZEN FUER SATELLITENKOMMUNIKATIONS-EMPFAENGER

摘要

A surface acoustic wave (SAW) filter for suppressing surface to surface interference for a satellite communication receiver comprises two input (IDT1 and IDT2) and one output (IDT3) interdigital transducers constructed and arranged on a common piezoelectric substrate. The widths of the adjacent portions of electrodes and the spaces between the electrodes of the input interdigital transducers are adjusted based upon the principle of a transversal filter so that the frequency response of the input interdigital transducer (IDT1) has a predetermined pass band width and the transducer (IDT2) has a reduced gain in a frequency range which may include an interference signal. A switch SW switches the input signal into either of the transducers IDT1 and IDT2. <IMAGE>