Duplexer incorporating thin-film bulk acoustic resonators (FBARs)
US6262637A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1999 |
| Grant date | Jul 17, 2001 |
| Priority date | — |
| Expiry date | Jun 2, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/706
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An FBAR-based duplexer that comprises a first port, a second port, a third port, a first band-pass filter connected between the first port and the third port and a series circuit connected between the second port and the third port. The first band-pass filter includes a first ladder circuit having shunt and series elements. Each of the elements of the first ladder circuit comprises a film bulk acoustic resonator (FBAR). The series circuit includes a 90.degree. phase shifter in series with a second band-pass filter. The second band-pass filter includes a second ladder circuit having shunt and series elements. Each of the elements of the second ladder circuit comprises a film bulk acoustic resonator. A band-pass filter comprising shunt elements and series elements in which the series elements and the shunt elements are connected to form a ladder circuit, and each of the elements includes a film bulk acoustic resonator (FBAR).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.