| 摘要 |
A monitoring method to monitor and/or protect modules, in particular a radio-frequency antenna of a magnetic resonance system, includes a measurement step in which at least one first characteristic monitoring variable is measured by at least one first measurement unit, and at least one calculation step in which at least one maximum limit value for a power and/or a voltage within the module is calculated using the at least one first measured characteristic monitoring variable. At least one second characteristic monitoring variable, different than the at least one first characteristic monitoring variable, is measured in the measurement step. |
| 主权项 |
1. A method for monitoring a radio-frequency (RF) antenna of a magnetic resonance apparatus, comprising the steps of:
operating a magnetic resonance apparatus having an RF antenna, by supplying voltage to said RF antenna via a first feed line comprising a first capacitor at an infeed point of said first feed line to said RF antenna, and via a second feed line comprising a second capacitor at an infeed point of said second feed line to said RF antenna, aid voltage said RF antenna to operate with an elliptical voltage distribution that causes said RF antenna to emit said RF energy at a transmission power; during said operation of said RF antenna in said magnetic resonance system, measuring a first characteristic monitoring variable, in one of said feed lines, associated with said operation of said RF antenna, said first characteristic monitoring variable being selected from the group consisting of power amperage and voltage; also during said operation of said RF antenna, measuring a second characteristic monitoring variable, in another of said feed lines, associated with said operation of said RF antenna, that is different from said first characteristic monitoring variable; and supplying said first and second characteristic monitoring variables to a computerized processor and, in said computerized processor, automatically calculating, in a first calculation step, a maximum limit value for voltages at said first capacitor and said second capacitor at said respective infeed points of said RF antenna, from said first and second characteristic monitoring variables and, in a second calculation step, a maximum limit value of said elliptical voltage distribution within the RF antenna as a value of a semimajor axis of said elliptical voltage distribution within said RF antenna produced by said respective voltages at said first and second capacitors; and making said maximum limit value of said elliptical voltage distribution, as said value of said semimajor axis of said elliptical voltage distribution, available in electronic form at an output of said computerized processor. |
