Line transformer
US4992769A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 28, 1989 |
| Grant date | Feb 12, 1991 |
| Priority date | — |
| Expiry date | Nov 28, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F2027/2809
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A line transformer suited for coupling the antenna of a nuclear magnetic resonance tomography apparatus to the RF transmission and reception circuitry is formed by a flat dielectric substrate having two congruent interconnect structures on the opposite major faces thereof. Each of the interconnect structures has two patterns of concentric conductor runs or strips, which are arranged mirror-symmetrically relative to a symmetry axis on both major faces of the substrate. The symmetry axes proceed parallel to each other, and are in registry with each other. A four port differential transformer without ferromagnetic material is obtained, which behaves symmetrically relative to the third and fourth ports, as seen from the first port as well as from the second port.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.