Calibration of Radiation Monitors
As a service for external customers, the working group 2.21 offers the calibration of small, mostly portable RF field sensors (known as ‘radiation monitors’) which are commonly used for ‘electromagnetic compatibility’ (EMC) measurements and for personal security measurements.
The most important aspects for calibration are:
For the calibration of commonly used RF field sensors (‘radiation monitors‘) the fields will be generated in an TEM cell or a GTEM cell, depending on the task and the size of the device.
Usually the PTB calibration in the GTEM cell includes the calibration of the transfer function and of the inisotropy, i. e. the frequency and orientation dependent display of the instrument at a given calibration field strength (for isotropic sensors). The whole instrument will be exposed to the field (whole instrument exposition).
As additional measurements are possible:
Determination of the display linearity of the instrument. In case of amplitude modulation the modulation index dependence of the display value. For these measurements a TEM cell with a septum height of 0.3 m, an upper cut-off frequency of 150 MHz and a maximum field strength of 600 V/m is available.
For the calibration of transfer field sensor instruments with miniaturized sensors the detector characteristics and the transfer function of the sensor will be measured in the ‘micro TEM cell‘ at different ambient temperatures. In addition to the PTB calibration certificate these calibration data will be provided for the instrument control programm in electronic form.
