Feasibility Of An Automated Near-Field Scanner Approach : A Repurposed 3D-printer for consistent EMI-scanning

Sammanfattning

In this thesis, the feasibility of constructing a semi-automated platform for EMI scanning was investigated. The work included evaluating the feasibility of repurposing a 3D printer into an EMI-measuring motion platform, along with near-field probes and a spectrum analyzer. To investigate the possibility, several tests were conducted. The different tests included noise floor measurement, mechanical repeatability, position repeatability, parameter studies, resulting heatmap, scanner comparison, EMC chamber comparison, and data validation. The repurposed 3D printer platform achieved position repeatability standard deviations of 0.0036 mm,0.0044 mm, and 0.0161 mm in the X-, Y-, and Z-axes, respectively. Six repeated near-field scans showed an amplitude standard deviation below 4 dB at three selected emission points with high-, medium-, and low-amplitude emissions. The measurement of the ambient and printer-interfering noise floor showed that it is possible to measure in an office environment, but with regard to certain frequency bands, such as radio and telephony. The selection of system parameters, including probe selection, height, angle, step size, and spectrum analyzer settings, is crucial.The system is also capable of finding correlated frequencies between an EMC test chamber result and the same measuring object applied on the scanner platform.