Measuring Transient and Steady State Electric Field Emissions of Space Equipment for EMC and Cleanliness Purposes

Most of the space missions carry measuring instruments that are sensitive to electric fields and require strict electromagnetic cleanliness. Therefore the variations of electric fields from platform equipment have to be correctly characterized, measured and modelled. The standard measurement procedure for ELF electric field (below 250 KHz) is according to MIL-STD-461-G, where a single measurement at 1 m distance is acquired usually with a monopole antenna. Since this measurement is in the near field region, no polarization information is available and the field spectral and spatial dependency is very hard to be estimated with a single acquisition of radiated emissions. Authors in this work are proposing a measurement setup, without deviating from the MIL-STD-461-G, capable to provide adequate information in order to estimate the electric field distribution when employing equivalent dipole modelling for accurate source identification. Moreover, authors propose an approach to measure transient states of the equipment in order to be analysed and modelled.