Interdigital transducer with distibuted excitation
AssigneeEpcos AG
InventorAndreas Bergmann
Life of this patent
Estimating the term…
Abstract
An interdigital transducer for a surface acoustic wave includes an acoustic track with a width of BSges and subtransducers arranged adjacent to each other on the acoustic track and connected in series. The subtransducers include, in a transverse direction, n series subtransducers each having a track width of BSxi (i=1, 2, . . . n(x); n (x)≧2). In the subtranducers BS ges = ∑ i = 1 n BS xi , BSxi does not equal BS(x+1)i.
Claims25
An interdigital transducer for a surface acoustic wave component, the interdigital transducer comprising:
- an acoustic track having a width of BSges;
- and
- m (m≧2) subtransducers arranged adjacent to each other on the acoustic track and connected in parallel;
- wherein each of the in subtransducers comprises n series subtransducers each having a track width of BSxi (x=1 . . . m, i=1 . . . n);
- wherein:
- BS
- ges
- =
- ∑
- i
- =
- 1
- n
-
-
- BS
- xi
- ,
- and
- BSxi does not equal BS(x+1)i for at least two series subtransducers;
- and
- wherein at least one of the m subtransducers further comprises floating electrode combs having different lengths that divide the n series subtransducers.
An interdigital transducer for a surface acoustic wave component, the interdigital transducer comprising:
- an acoustic subtrack having a width of BSges;
- and
- m (m≧2) subtransducers arranged adjacent to each other on the acoustic subtrack and connected in parallel;
- wherein each of the m subtransducers comprises n series subtransducers each having a track width of BSxi (x=1 . . . m, i=1 . . . n);
- wherein:
- BS
- ges
- =
- ∑
- i
- =
- 1
- n
-
-
- BS
- xi
- ,
- and
- BSxi does not equal BS(x+1)i for at least two series subtransducers;
- and
- wherein the in subtransducers comprise a first group of subtransducers, the first group of subtransducers being connected in series to a second group of subtransducers that are connected in parallel and that are arranged on same acoustic track as the first group of subtransducers.
An interdigital transducer for a surface acoustic wave component, the interdigital transducer comprising:
- an acoustic track having a width of BSges;
- and
- m (m≧2) subtransducers arranged adjacent to each other on the acoustic track and connected in parallel;
- wherein each of the m subtransducers comprises n series subtransducers each having a track width of BSxi (x=1 . . . m, i=1 . . . n);
- wherein:
- BS
- ges
- =
- ∑
- i
- =
- 1
- n
-
-
- BS
- xi
- ,
- and
- BSxi does not equal BS(x+1)i for at least two series subtransducers;
- and
- wherein the interdigital transducer comprises a recursive transducer with divided reflection.
An interdigital transducer for a surface acoustic wave component, the interdigital transducer comprising:
- an acoustic track having a width of BSges;
- and
- m (m≧2) subtransducers arranged adjacent to each other on the acoustic track and connected in parallel;
- wherein each of the in subtransducers comprises n series subtransducers each having a track width of BSxi (x=1 . . . m, i=1 . . . n);
- wherein:
- BS
- ges
- =
- ∑
- i
- =
- 1
- n
-
-
- BS
- xi
- ,
- and
- BSxi does not equal BS(x+1)i for at least two series subtransducers;
- and
- wherein at least one part of the n series subtransducers in at least one of the m subtransducers includes withdrawal weighting.
An interdigital transducer for a surface acoustic wave component, the interdigital transducer comprising:
- an acoustic track having a width of BSges;
- and
- m (m≧2) subtransducers arranged adjacent to each other on the acoustic track and connected in parallel;
- wherein each of the m subtransducers comprises n series subtransducers each having a track width of BSxi (x=1 . . . m, i=1 . . . n);
- wherein:
- BS
- ges
- =
- ∑
- i
- =
- 1
- n
-
-
- BS
- xi
- ,
- and
- BSxi does not equal BS(x+1)i for at least two series subtransducers;
- and
- wherein at least one part of the n series subtransducers in at least one of the m subtransducers includes overlap weighting.
An interdigital transducer for a surface acoustic wave component, the interdigital transducer comprising:
- an acoustic track having a width of BSges;
- and
- m (m≧2) subtransducers arranged adjacent to each other on the acoustic track and connected in parallel;
- wherein each of the m subtransducers comprises n series subtransducers each having a track width of BSxi (x=1 . . . m, i=1 . . . n);
- wherein:
- BS
- ges
- =
- ∑
- i
- =
- 1
- n
-
-
- BS
- xi
- ,
- and
- BSxi does not equal BS(x+1)i for at least two series subtransducers;
- and
- wherein the m subtransducers, and the series subtransducers within each of the m subtransducers, are arranged symmetrically.
An interdigital transducer for a surface acoustic wave component, the interdigital transducer comprising:
- an acoustic track having a width of BSges;
- and
- m (m≧2) subtransducers arranged adjacent to each other on the acoustic track and connected in parallel;
- wherein each of the m subtransducers comprises n series subtransducers each having a track width of BSxi (x=1 . . . m, i=1 . . . n);
- wherein:
- BS
- ges
- =
- ∑
- i
- =
- 1
- n
-
-
- BS
- xi
- ,
- and
- BSxi does not equal BS(x+1)i for at least two series subtransducers;
- and
- wherein an excitation at a center of the interdigital transducer is greater than an excitation at an edge of the interdigital transducer.
An interdigital transducer for a surface acoustic wave component, the interdigital transducer comprising:
- an acoustic track having a width of BSges;
- and
- m (m≧2) subtransducers arranged adjacent to each other on the acoustic track and connected in parallel;
- wherein each of the m subtransducers comprises n series subtransducers each having a track width of BSxi (x=1. . . m, i=1 . . . n);
- wherein:
- BS
- ges
- =
- ∑
- i
- =
- 1
- n
-
-
- BS
- xi
- ,
- and
- BSxi does not equal BS(x+1)i for at least two series subtransducers;
- wherein subtransducers that are internal to the interdigital transducer are more evenly divided into series subtransducers than subtransducers that border an exterior of the interdigital transducer;
- and
- wherein a product
- ∏
- i
-
-
- BS
- xi
- of track widths of series subtransducers associated with an internal subtransducer with m>x>1, is larger than a product
- ∏
- i
-
-
- BS
- xi
- of track widths of series subtransducers associated with a subtransducer with x=1 or m that borders the exterior of the interdigital transducer.
Dependencies are inferred from the claim text.