Saw filter with a coupled saw impedance element
US5610566A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 1994 |
| Grant date | Mar 11, 1997 |
| Priority date | — |
| Expiry date | Jul 26, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/6493
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
This invention relates to an electronic device having a frequency dependent signal transfer characteristic which is electrically coupled to at least one SAW transducer. The SAW transducer acts as a SAW impedance element since it exhibits frequency dependent electrical characteristics. Such characteristics are utilised so that the transmission loss of the SAW impedance element is high in a relatively low signal transfer region of the signal transfer characteristic of the electronic device, and low in a relatively high signal transfer region of the signal transfer characteristic of the electronic device. This has the advantage that signals outside of the passband of the electronic device can be attenuated without increasing the transmission loss of the electronic device in its passband.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.