Analysis of effects of variable parameters on inter-laboratory comparisons for radiated emission test

Abstract

In this paper, the effect of the antenna height (constant or variable) was analyzed during inter-laboratory comparisons (ILCs) for radiated emission (RE) test. The electric field strength that is radiated from an electronic device is measured on RE test. The measured values are can be differential depending on some variables. Measurement distance between receiving antenna and product to be tested must be constant during RE tests of ILC. The Equipment under Test (EUTs) height also has to be same. The antenna can be constant or can be movable. This situation affects the measurements majorly. The ILCs can be success or failed because of the varying parameters. EN 17025 “General requirements for the competence of testing and calibration laboratories” requires that test and calibration laboratories continuously shall prove proficiency in performing measurements as part of assuring the quality of their results and monitor the validity of performed tests. Comparison tests between test setup in different laboratories are important from the point of test accuracy, validity, repeatability. In the same way, these ILCs are the requirement of laboratory accreditation. Accredited test laboratories shall participate to ILCs according to the requirements of the EN 17043 “Conformity assessment — General requirements for proficiency testing standard”. ILCs should be performed more carefully and more detailed for primary critical tests that have also complex setup such as RE test. In this study, the effect of the measurement height on the ILCs for RE test was examined. The results also were evaluated based on the |En| scores.