Microwave hairpin-comb filters for narrow-band applications
US6130189A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 23, 1998 |
| Grant date | Oct 10, 2000 |
| Priority date | — |
| Expiry date | Sep 23, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S505/866
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Microwave hairpin-comb filters utilize a plurality of hairpin (i.e., folded) half-wavelength microstrip or stripline resonators arranged side-by-side and all with the same orientation. The coupling regions between resonators extend parallel to the sides of the resonators for substantially 1/8 to 1/4 wavelength at the frequency of resonance of the resonators. This length of coupling region between resonators, along with all resonators being oriented in the same direction, result in resonance effects in the coupling regions between the resonators. These effects greatly reduce the couplings between the resonators so that the resonators can be very closely spaced so as to produce a compact filter structure yet still have a narrow passband. The structure can also be made to produce poles of attenuation adjacent to the passband in order to enhance the filter cutoff characteristic. The filter structure can be conveniently tuned using asymmetric dielectric pieces which rotate above an interdigital conductor pattern placed between the open ends of each resonator, the axis of rotation being normal to the substrate. This manner of tuning is particularly attractive for narrow-band, very low lo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.