An Alternative Method for Calibration of monopole and loop antenna in GTEM Cell

Recently, one of issues in IEC CISPR SC A is the standardization of measurement method for radiated emission below 30 MHz. Ad-hoc group 1 of CISPR SC A/WG1 is dealing with the method of antenna calibration and test site validation. This paper presents an alternative method for calibration of the monopole and loop antennas in GTEM cell that are used for EMC testing on the frequencies below 30 MHz. With the limitation of height, the floor ground plane of GTEM Cell 1250 was modified in order to accommodate a base unit of a 1 m length monopole antenna, and then the field uniformity assessment in the areas for monopole and loop antennas was performed and analyzed in the frequency range from 10 kHz to 30 MHz. The antenna factors of reference antennas were calibrated by ECSM and TEM Cell method respectively according to CISPR 16-1-6. Finally the calibration results using reference antenna method in GTEM cell with one active monopole antenna and one passive loop antenna were compared with the results calibrated by the methods of CISPR 16-1-6.