This paper covers the use of oscilloscopes in near-field, pre-compliance radiating tests. Using commercial low-cost planar magnetic probes, a procedure is presented to use the time-domain waveforms to address emitted radiation patterns. In spite of its lower sensitivity in relation to spectrum analyzers, a comparison between both instruments is presented, with the inferior response of the oscilloscope compensated by means of off-the-shelf broadband amplifiers. Complete system calibration is described and performed, relating the voltage measurements in a transmission-line structure to field amplitudes provided by a full-wave simulation. Two different typical devices are tested using the procedure here developed: a direct current motor, driven by a square wave, and a microprocessor board. Results show the potential use of the almost omnipresent instrument in sophisticated field evaluations, enabling its use in situations where spectrum analyzers are not available.
Marcelo Bender Perotoni,
Walter M. Silva,
Danilo B. Almeida,
Kenedy M. G. Santos,
"Pre-Compliance Near-Field Tests Based on Oscilloscopes," Progress In Electromagnetics Research M,
Vol. 110, 109-118, 2022. doi:10.2528/PIERM22032504
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