Whitepaper
Streamline EMC Compliance Testing with Prescan Analysis Tools
This Keysight application note details errors introduced during EMC prescan measurements, specifically focusing on frequency and amplitude inaccuracies. The paper explains that stepping or sweeping receivers can report emissions at incorrect frequencies (up to 60 kHz offset with common settings) or with reduced amplitudes (potentially up to 6dB lower), leading to false negatives in compliance testing. While increasing data points during the prescan reduces errors, it also increases test time. The note advocates for using spectrum analysis and IF spectrum monitoring – available on instruments like the Keysight N9038A MXE EMI receiver – to review suspect signals before final measurements, correcting both frequency and amplitude values for accurate results against standards like CISPR. This combined approach enables efficient, reliable EMC compliance testing by leveraging the benefits of prescan methodologies while mitigating their inherent inaccuracies.