JUNO/Waves - Calibration of the JUNO/Waves Antenna System
The polar magnetosphere of Jupiter is practically uncharted territory, and the primary objective of the JUNO/Waves instrument is to explore this region, and several polar orbits should directly pass through the so-called auroral acceleration region that has never been explored.
The Waves instrument utilizes a short electric dipole antenna and a body- mounted search coil magnetometer that will enable an initial reconnaissance of the plasma waves. Additionally it should identify in-situ the sources of hectometric (HOM) and decametric (DAM) radio emissions. These electromagnetic emissions are thought to be generated by the so-called cyclotron maser instability mechanism close to the gyro-frequency of magnetospheric electrons in the auroral regions of the radio planets.
In the course of the project the electric field dipole within the JUNO/Waves instrument was analysed using two different methods: experimental measurements and numerical simulations. The experimental method, called rheometry, is essentially an electrolytic tank measurement using a scale model of the spacecraft; the numerical simulations solve the underlying field equations by means of electromagnetic computer programmes.
The project provides calibration information, in particular the exact antenna reception properties of the instrument and the corresponding antenna capacitances, thus improving the overall performance of the instrument.
The accuracy of the evaluation and interpretation of the electric field observations made on board the JUNO spacecraft will be significantly improved by this detailed antenna analysis.
Austrian Academy of Sciences (ÖAW), Space Research Institute (IWF) - Manfred Sampl
- The University of Iowa, Department of Physics and Astronomy - William S. Kurth
- Dresden University of Technology, Chair for RF Engineering - Dirk Plettemeier
Austrian Academy of Sciences (ÖAW) - Space Research Institute (IWF)
Tel.: +43 (316) 4120 - 629