Antenna coupling circuit for magnetic resonance imaging
US4731585A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 24, 1987 |
| Grant date | Mar 15, 1988 |
| Priority date | — |
| Expiry date | Feb 24, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/3621
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A coupling circuit for coupling an inductive coil antenna of a magnetic resonance imaging system to receiver circuitry is provided which includes capacitive circuitry, resistive circuitry, and capacitive transformer circuitry. The capacitive circuitry is coupled in parallel with the antenna to provide capacitive reactance to the coupling circuitry. Resisitive circuitry is coupled in parallel with the antenna and with the capacitive circuitry to provide resistance R in the coupling circuit when an AC voltage at the resonant frequency of the coupling circuit is applied. Capacitive transformer circuitry is coupled in series with the antenna for transforming the resistance value R of the resistive circuitry into a transformed resistance value R'. This increases the apparent resistance of the coupling circuit in parallel with the antenna without increasing the actual resistance and power consumption of the coupling circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.