volume | PIER Journals

Abstract

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.

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Prof. Marcelo Bender Perotoni

Dr. Walter M. Silva

Dr. Danilo B. Almeida

Dr. Kenedy M. G. Santos