Mode filters
US4222018A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 7, 1978 |
| Grant date | Sep 9, 1980 |
| Priority date | — |
| Expiry date | Jul 7, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01P1/163
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The invention relates to mode filters for millimetric waves. The mode filter provided includes a circularly sectioned waveguide divided into a number of equal sectorial channels. Dielectric mode perturbing material is provided in all but one of the channels. This material extends in the direction of the H-field so as not to interfere with a wanted mode of a propagated signal but to perturb the current lines of an unwanted TE.sub.On mode so that an -unwanted TE.sub.On mode in the channel containing the dielectric material undergoes a .pi.radian phase shift relative to the TE.sub.On mode in the remaining channel which remaining channel has a conductive sectorial ridge of the same cross section as the sectorial channels and extending in the direction of the H-field the ridge being of such a radius that differential phase shifts produced by the perturbation effect of the mode perturbing material of the wanted mode cut-off frequency are substantially reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.