EMC Analysis and Trade-Off for Envision Subsurface Radar Sounder Accommodation

The electromagnetic compatibility is a key topic on Envision spacecraft, mainly driven by the sensitivity of radars radio-frequency front-end electronics. In particular, the subsurface radar sounder works in a relatively low frequency rage (9 MHz central frequency) with an extremely wide band (5 MHz). This frequency range is typically polluted by spacecraft platform switching elements (e.g. converters) and signal clocks. On the other hand, due to the high power transmitted, it is crucial to design the spacecraft protecting the equipment from the high field strength generated during radars operations. Alongside electromagnetic compatibility, a primary challenge in designing a spacecraft equipped with radar sounders is to guarantee its radio-frequency performance. The accommodation and the decoupling between the dipole, used as radiating element, and the other appendages of the spacecraft is fundamental to ensure the requested gain and providing a smooth and monotonic impedance.