Branching filter and communication device
US7304551B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 10, 2003 |
| Grant date | Dec 4, 2007 |
| Priority date | — |
| Expiry date | Oct 10, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/706
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A branching filter and a communication device have excellent characteristics and an optimized configuration of a transmitting filter and a receiving filter. The branching filter includes a transmitting filter and a receiving filter wherein piezoelectric thin film resonators including a piezoelectric thin film sandwiched between opposed electrodes are arranged in a ladder type configuration on an opening or a recess of a substrate. The transmitting filter and the receiving filter are connected in parallel to an antenna terminal. The piezoelectric thin film resonators defining the transmitting filter and the piezoelectric thin film resonators defining the receiving filter are different from each other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.