Saturation of active loop antennas

The EMC community is working towards shorter test distances for radiated emission measurements in the frequency range from 9 kHz to 30 MHz. This would reduce the cost for testing dramatically since typical absorber lined shielded rooms can be used for magnetic field strength measurements. The reduction of the test distance will lead to higher emission limits. In combination with pulsed signals commercially available active loop antennas are not suitable due to insufficient dynamic range. Measuring a 2 % duty cycle signal will increase the dynamic range by 30 dB. Pulsed signal have to be taken into consideration because pulse width modulation is one of the possibilities to control power in wireless charging applications.