Narrow-band absorptive bandstop filter with multiple signal paths
US7323955B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 6, 2005 |
| Grant date | Jan 29, 2008 |
| Priority date | — |
| Expiry date | Feb 21, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01P1/2039
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An absorptive bandstop filter includes at least two frequency-dependent networks, one of which constitutes a bandpass filter, that form at least two forward signal paths between an input port and an output port and whose transmission magnitude and phase characteristics are selected to provide a relative stopband bandwidth that is substantially independent of the maximum attenuation within the stopband and/or in which the maximum attenuation within the stopband is substantially independent of the unloaded quality factor of the resonators. The constituent network characteristics can also be selected to provide low reflection in the stopband as well as in the passband. The absorptive bandstop filter can be electrically tunable and can substantially maintain its attenuation characteristics over a broad frequency tuning range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.