A novel automated phasor measurement system for validated and traceable EMC/EMI near-field analysis

Abstract

Traceable high precision EMC/EMI measurements will simplify product specifications and reduce the liability of OEMs. A novel automated near-field testbed for system- to chip-level EMC/ EMI in the RF domain based on photonic phasor probes is presented. The scanning system combines a large scanning volume with micrometer resolution. An optical surface reconstruction system allows the surface structure of the device under test (DUT) to be measured with better than 20 μm uncertainty, allowing scans at a precisely known distance above arbitrary electronic components. Miniaturized active electro-optical time-domain ultra-wideband Eand H-field sensors for the frequency range from 0.01 to 6 GHz combined with a high speed vector signal analyzer are applied to measure the EM phasor field distribution with a dynamic range of >120 dB. The fully isolated probes eliminate perturbations of the EM fields generated by the DUT compared to electrically connected probes and offer up to 60 dB better sensitivity than passive 42 2016 IEEE Electromagnetic Compatibility Magazine - Volume 5 - Quarter 2 electro-optical probes. The testbed enables high precision broadband near-field 3D scans for EMC/EMI analysis to be performed and excellent inter-laboratory repeatability to be achieved. In the near future, it will be possible to reconstruct emission data from the near field to the far field.