Title :
Verifying RF amplifier characteristics at EMC lab
Author :
Manara, Angelo ; Colombo, Franco
Author_Institution :
ABB Ricerca S.p.A., Milan, Italy
Abstract :
This paper deals with the measurement of AM percent modulation of the radio-frequency fields used in RF immunity test (conducted and radiated) International standards set a requirement on the amplitude modulation depth of the RF voltages to be injected in CDN (or antennas) and prescribe a tolerance around the nominal value to be verified using a scope. Such small tolerance (5%) is difficult to measure with an oscilloscope and (moreover) other discrepancies of the modulated signal are not visible on the oscilloscope. Using a spectrum analyzer the modulation depth and the harmonic contents as well other types of distortion can be seen at a glance with higher accuracy
Keywords :
amplitude modulation; electromagnetic compatibility; laboratory techniques; measurement errors; measurement standards; radiofrequency amplifiers; radiofrequency interference; spectral analysers; AM percent modulation measurement; CDN; EMC lab; EMI receivers; RF amplifier characteristics; RF immunity test; RF voltages; amplitude modulation depth; antennas; conducted emission testing; distortion; harmonic contents; international standards; measurement uncertainty; modulated signal; oscilloscope; radiated emission testing; radio-frequency fields; spectrum analyzer; tolerance; Amplitude modulation; Antenna measurements; Distortion measurement; Electromagnetic compatibility; Immunity testing; Measurement standards; Oscilloscopes; Radio frequency; Radiofrequency amplifiers; Voltage;
Conference_Titel :
Electromagnetic Compatibility, 1999 IEEE International Symposium on
Conference_Location :
Seattle, WA
Print_ISBN :
0-7803-5057-X
DOI :
10.1109/ISEMC.1999.812932
