The Huygens Doppler Wind Experiment is designed to determine the
velocity of Titan's zonal winds.
The wind is measured over a height range from 0 - 160 km from its
Doppler signature on the Probe's radio relay signal to the
Cassini Orbiter.
The stringent frequency stability required for the DWE measurement
is assured by
(a) generating the transmitted signal with a externally supplied
ultrastable oscillator (TUSO), and
(b) providing the receiver with an identical ultrastable
external oscillator (RUSO).
Information on probe dynamics (spin rate, spin phase,
parachute swing) and large-scale turbulence in the Titan atmosphere
are secondary objectives of the investigation.
The reconstructed probe trajectory using DWE data provides
the best estimate of Huygens' final place of rest on Titan.
This paper presents results of a research project partially funded
by the Deutsche Agentur für Raumfahrtangelegenheiten (DARA) GmbH
under contract 50 OH 9207.
The responsibility for the contents is assumed by the authors.
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