| 摘要 |
The invention relates to a method for determining an electric voltage u(t) and/or an electric current i(t) of an HF signal in an electrical cable (10) on a calibration plane (14) by measuring in the time domain using a time domain measuring device (34). In a first measuring step, using a directional coupler (18), a first portion v3(t) of a first HF signal, running from a signal input (19) in the direction of the calibration plane via the directional coupler, is decoupled, fed to the time domain measuring device at a first measuring input (36), and measured there, and a second portion v4(t) of a second HF signal, running from the calibration plane in the direction of the signal input via the directional coupler, is decoupled, fed to the time domain measuring device at a second measuring input (38), and measured there. The signal portions v3(t), v4(t) are converted into the frequency domain using a first mathematical operation, then absolute wave frequencies in the frequency domain are determined on the calibration plane using calibration parameters, and finally the determined absolute wave frequencies are converted into the electric voltage u(t) and/or the electric current i(t) of the HF signal in the time domain on the calibration plane, using a second mathematical operation. In a previous calibration step, the calibration parameters are determined with the aid of a calibration device in accordance with the frequency f and depending on the reflection factor at at least one of the measuring inputs of the time domain measuring device, and the absolute wave frequencies on the calibration plane are determined in the measuring step using the calibration parameters (e00,r(G3, G4), e01,r(G3, G4), e10,r(G3, G4), e11, r(G3, G4)), wherein G3, G4 are the reflection factors of the inputs of the time domain measuring device. |
