Thermal Radiation Model (TRM) for ESA's Ground-based Telescopes

Paper number

IAC-05-C2.P.12

Author

Thomas Bornkessel, TU Darmstadt, Germany

Year

2005

Abstract

The construction of high precision fast tracking ground antennas
(ESA) is a very challenging and complex task. In order that an
antenna meets his required performance it has to fulfill certain
criteria concerning its static properties. Due to the increasing
demands on standards and performance for higher frequency
operations as Ka-band these criteria become more and more
stringent.

In particular, deviations due to thermal effects as temperature
gradients within the structure and the ambient temperature can
have a very strong impact on the performance of the antenna. To
achieve the required high accuracy with the current groud-based
antennas the right temperature distributions within the antenna
has to be known under crucial boundary conditions. For example the
temperature gradients within the antenna structures are only based
on experience or transferred measurements and are not verified.


As a result of the development of a thermal radiation model for
ESA's ground-based telescopes it is now possible to predict the
temperature distribution in real-time. The numerical model
considers thermal heat transfer by radiation with the sky, the
ground and with the structural parts itself taking into account
the environment temperature, the wind speed and the wind direction.
The known temperature distribution can be transferred to a
numerical structural model for calculating the resulting surface
and pointing errors. These information can be transferred to the
antenna control unit for keeping the optimum tracking position in
real-time.

Beyond the discussed thermal radiation model we will give further
an outlook for antenna thermal design strategies and necessary
thermal material properties to improve the performance of
ground-based telescopes.

Abstract document

IAC-05-C2.P.12.pdf

Manuscript document

IAC-05-C2.P.12.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.