Publication detail

The Efficient Method of Ambient Signals Cancellation in EMC Interference Measurements

SVAČINA, J.

Original Title

The Efficient Method of Ambient Signals Cancellation in EMC Interference Measurements

Type

journal article - other

Language

English

Original Abstract

The paper deals with some aspects of EMC interference signal measurements in the presence of undesired ambient signals that appear mainly by an open field test site measurement. The method for efficient ambients cancellation is described, and discussed in the article from theoretical, as from practical point of view. The method, which is in the form of special hardware/software utilities already implemented in some modern electromagnetic interference (EMI) receivers, is based on ambient signals storing in an internal receiver memory and then on their “subtracting” from actual measured signals. Results of this concept depend first of all on the character of actual ambients signals, and on their time and frequency stability. After the theoretical background of the concept is stated, its effectiveness was checked in series of EMI measurements by using the EMI Spectrum Receiver from the Seaward Ltd. in the frequency range from 9 kHz to 1000 MHz. By this, we have used various types of simulated as well as real existing ambient signals and various modes of EMI receiver. The cancellation of ambients was tested for continuous harmonic signal, for continuous square wave ambient signal, and for signal of broadband white noise character. The simultaneous treatment of these types of signals was also investigated. All tests were executed under the Peak-Detection mode of the EMI receiver, some of their also by using the Quasi-Peak detection mode. Our measurement demonstrated, that the “subtraction” effect is more effective in Quasi-Peak mode measurement, as in Peak detector mode. Simultaneously, the accuracy of the cancellation increases with decreasing of the measuring frequency span. Thus, our practical experiences show, that by taking a proper measuring process, the obtained results are very good, and the cancellation of undesired ambients can be made very effectively.

Keywords

EMC, EMI, interference measurement, ambient signals

Authors

SVAČINA, J.

RIV year

2003

Released

1. 10. 2003

ISBN

1335-8243

Periodical

Acta Electrotechnica et Informatica

Year of study

3

Number

3

State

Slovak Republic

Pages from

5

Pages to

9

Pages count

5

BibTex

@article{BUT41478,
  author="Jiří {Svačina}",
  title="The Efficient Method of Ambient Signals Cancellation in EMC Interference Measurements",
  journal="Acta Electrotechnica et Informatica",
  year="2003",
  volume="3",
  number="3",
  pages="5",
  issn="1335-8243"
}