Balanced/unbalanced filter module and communication apparatus
US7498902B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 2007 |
| Grant date | Mar 3, 2009 |
| Priority date | — |
| Expiry date | Jun 22, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2250/00
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A balanced/unbalanced filter module includes a switch including a first port that inputs and outputs unbalanced signals in a first frequency band, a second port that inputs and outputs unbalanced signals in a second frequency band, and a third port that inputs and outputs unbalanced signals in these two frequency bands. The switch switches a signal path. An unbalanced I/O port of a first filter that passes signals in the first frequency band is connected to the port. A port of a second filter that passes signals in the second frequency band is connected to the port. Individual balanced I/O ports of each of the first and second filters are connected to first and second branch ports with substantially the same electrical length. A balance coil for impedance matching is provided between the first and second branch ports.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.