Patent ID: 8049582
Filing Date: 2011-11-01
Classification: H03H

Abstract:
1. A transversal filter, comprising a piezoelectric substrate; at least one acoustic track formed on the piezoelectric substrate; and at least one SAW input transducer and at least one SAW output transducer arranged in each track; wherein at least one input transducer and at least one output transducer has a distributed excitation comprising a continuous excitation function having a main lobe and at least one tail lobe with a sign of excitation different than the main lobe; and an excitation strength S in the main lobe being greater than an excitation strength G of the at least one tail lobe by a factor of x, where 8≧x≧2, x and x is a real number; wherein the at least one input transducer of each track is divided into a main lobe sub-transducer and a tail lobe sub-transducer by electrically separating at least one bus bar of the input transducer into two parts; wherein the main lobe and tail lobe sub-transducers adjoining each other in a longitudinal direction; and wherein the main lobe of excitation being assigned to the main lobe sub-transducer, the at least one tail lobe being assigned to the tail lobe sub-transducer.