Cascade waveguide triple-mode filters useable as a group delay equalizer
US4630009A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 24, 1984 |
| Grant date | Dec 16, 1986 |
| Priority date | — |
| Expiry date | Jan 24, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01P1/2082
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A bandpass filter has a plurality of cascade wave-guide cavities each resonating in three independent orthogonal modes. The cavities can be cylindrical or have a square cross-section. Where the cavities are circular, each cavity resonates in TE.sub.111 or TE.sub.010 modes simultaneously. Where the cavities have a square cross-section, each cavity resonates in TE.sub.011 and TM.sub.110 modes simultaneously. Between each triple-mode cavity, there is located an iris having an aperture with four separate radial slots that are offset from a center of the iris. The filter is capable of producing an elliptic function response. In a variation of the invention, an allpass filter has an output that is short circuited and, when used in conjunction with a circulator, it functions as a group delay equalizer. Previous triple-mode filters are not capable of producing an acceptable result relative to dual-mode filters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.