Site contributions for radiated emission measurement uncertainties above 1 GHz

Guidance on accounting for site imperfections in the uncertainty evaluation of emissions measurement result is provided by CISPR 16-4-2. Site Voltage Standing Wave Ratio (SVSWR) results from the chamber are used as the basis for estimating the uncertainty contributions due to the site. In this paper, we investigate two aspects of the uncertainty evaluation, and provide a method to estimate the uncertainties based on measured SVSWR data. Firstly, considering that the SVSWR results are under-sampled and under-reported using the current method, is it valid to assume 6 dB as the maximum SVSWR of the chamber? Secondly, SVSWR measurements are only performed at the front, left, right, and center (optionally) of the quiet zone (QZ). We study if those locations are adequate representations of the entire QZ performance.