Spectral analysis of conducted emissions of DC/DC converters

This paper investigates spectral properties of conducted emissions (CE) of DC/DC converters used in space applications (e.g., onboard space vehicles). This is done in order to improve the accuracy of prediction models, recently developed, which foresee measurement of CE in the time-domain and subsequent time-to-frequency transformation. In particular, two phenomena are addressed in this work: (a) The time-variant behavior of CE, due to the instability of the DC/DC converter switching frequency; (b) the finite sensitivity of the measurement system resulting from the related noise floor. Proper signal processing procedures are proposed in order to bound the effects of such phenomena, and comparison of predictions versus experimental measurements are used to assess the effectiveness of the proposed approach.