Summary
International Symposium on Antennas and Propagation
2012
Session Number:3E3
Session:
Number:3E3-5
Pseudo EMI Measurement Using VNA and Optical Feeding Antenna for Site Performance Comparison among Public Testing Laboratories in Kanto-area in Japan
Michitaka Ameya, Satoru Kurokawa,
pp.-
Publication Date:2012/10/29
Online ISSN:2188-5079
Summary:
Recently, site evaluation of anechoic chamber for EMI over 1GHz has attracted much attention because EU and VCCI start the regulation for EMI above 1GHz from October 2010. In the international standard, CISPR16-1-4 , SVSWR method has defined as a site evaluation method for EMI anechoic chamber over 1 GHz. The SVSWR method is specialized for validating the anechoic chamber hence the relationship between SVSWR and the EMI results is not clear. Therefore, the quantitative evaluation of site performance is difficult by the SVSWR. On the other hand, round robin tests using a reference EUT have been conducted for comparing the site performance. A comb generator is generally used as a reference EUT in the round robin test for the EMI of the frequency range less than 1 GHz. As for the receiver, an EMI receiver or a spectrum analyzer is mainly used in EMI tests. However, the uncertainty of such receivers is very high. The typical uncertainties are +-1.5 dB for the amplitude stability, +-1.2 dB for the instability of preamp gain, +-0.3 dB for the calibration of cable loss and pre-amplifier gain, and +-1.0 dB for the mismatch between antenna and preamplifier according to CISPR16-4-2. Therefore, comparing the site performance using such receivers is inappropriate due to the bigger uncertainty. For the purpose of accurate comparison of site performances and reducing the uncertainty of the measurement, we propose a pseudo-EMI measurement using VNA and optical feeding antenna in this paper.