NSSDCA ID: 1978-071A-06
Mission Name: ESA-GEOS 2The instrument used two sets of three-axis search coil magnetometers, one for the ULF/ELF range (0.1 to 450 Hz) and one for the VLF range (0.3 to 30 kHz). Each search coil consisted of a high-permeability material with a high-density pick-up winding. Each set of the three coils was built into a single assembly and mounted on the locking 3-m booms at a distance of 2 m from the spacecraft. Typical sensitivities of these sensors in units of nT per sq root of Hz, were 1E-1 at 0.1 Hz, 2E-4 at 10 Hz, and about 3E-6 at 1 kHz. These sensors and some associated electronics consisting of (1) a large number of channel-selection switches, (2) a number of bandpass filters, (3) six swept-frequency analyzers (SFA), (4) a digital correlator, and (5) eight stepped-gain amplifiers, were a part of the ESA wave experiment S-300. These components were employed for the sensors described in 78-071A-07 (Pedersen) and 78-071A-10 (Ungstrup), and also the investigations described in 78-071A-05 (Petit) and 78-071A-11 (Beghin). Six analog channels of 450-Hz bandwidth and the digital correlator output were transmitted by the 95.25-kbs telemetry mode. The SFA covered the frequency range up to 77 kHz in 256 partly overlapping steps. The correlator provided an auto-correlogram of 128 points within 29 ms. Its bandwidth could be selected to be 2.5, 5.0, or 10.0 kHz. A cross-correlogram between two sensors could be provided. The correlator also operated in a time-sharing mode between auto- and cross-correlation. For additional details, see Perraut et al., Space Sci. Rev., v. 22, p. 347, 1978.
Questions and comments about this experiment can be directed to: Dr. H. Kent Hills
Name | Role | Original Affiliation | |
---|---|---|---|
Dr. Eigil Ungstrup | Other Investigator | Danish Space Research Institute | eu@osiris.gfy.ku.dk |
Dr. Jacquelyne M. Etcheto | Other Investigator | Centre National d'Etudes des Telecommunications | je@lodyc.jussieu.fr |
Dr. Roger E. Gendrin | Principal Investigator | Centre National d'Etudes des Telecommunications |