Method for monitoring an RF power amplifier, and an RF device, a monitoring device, and an MR system corresponding thereto

US7340225B2 · kind B2 · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Wolfgang Bielmeier · Erlangen, DE
• Klaus Ludwig · Erlangen, DE

Key dates

• Filing date: Feb 10, 2005
• Grant date: Mar 4, 2008
• Expiry date: Jun 2, 2026

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/3614
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

In a method for monitoring of a radio frequency power amplifier and a radio frequency device, a radio frequency monitoring device and magnetic resonance tomography system operable according to the method, radio frequency pulses emitted by a radio frequency power amplifier and are transmitted into a human subject by a transmission coil at temporal intervals. Measurement values that represent the power of the radio frequency pulses are measured at temporal intervals, and varying, predetermined power limit values are determined at temporal intervals. A control value representing the radio frequency dose emitted in a time window is determined based on a number of measurement values measured in the time window. Likewise, a limit control value representing a dose limit value allowed in the appertaining time window is determined based on the power limit values determined in the appertaining time window. The radio frequency power amplifier is limited in operation if and when the control value reaches or exceeds the limit control value.