Duplexer filter with an alternative signal path
US6559735B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 2000 |
| Grant date | May 6, 2003 |
| Priority date | — |
| Expiry date | Oct 31, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01P1/2136
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The present invention is a preferred monoblock ceramic bandpass duplexer filter. The preferred filter has at least three I/O pads. One of the pads is coupled to an antenna, another is connected to a transmission circuit and the last pad is connected to a receive circuit. The filter is comprised of two sections: a transmission section and a receive section. The transmission and receive sections include resonators disposed on respective sides of the antenna pad. A first alternative signal path is disposed adjacent the ends of the transmission resonators. A second alternative signal path is disposed adjacent to the ends of the receive resonators. Each alternative signal path couples adjacent and non-adjacent resonators. A further feature of the filter of the present invention includes a shunt zero resonator for the transmission section. To the contrary, the present invention allows the elimination of a shunt zero resonator for the receive section of the filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.