High Performance
Reflector Antennas
Through RUAG Space's numerous projects involving applications in
deep-space science, earth observation and telecommunications, the company
has been developing worldclass reflector antenna products since the 1970’s.
Worldclass reflector antennas
RUAG's reflectors cover diameters from 0.4 m to 3.3 m, and frequencies from the S-band up to 575 GHz.
RUAG Space's generic concept features very low mass, high thermal
stability and very high surface accuracy. Originally developed for scientific use, you can now reap the benefits of our reflector antenna
expertise in high performance designs for all types of applications
including commercial telecommunication payload antennas.
Technology
RUAG Space reflectors are of sandwich design. The skins consist of a number of highmodulus CFRP unidirectional prepregs with cyanate ester as a matrix, assuring low
moisture absorption. The honeycomb is either of low-mass aluminum type or of
carbon fiber type. All inserts, mounting and attachment structures are standardized.
For high-frequency antennas RUAG Space uses a thin layer of vacuum-deposited
aluminum on the reflectors.
RUAG's dichroic subreflectors use quarts/cyanate ester skins and honeycomb.
Inhouse software gives very accurate RF designs.
The SAR-Lupe 3.3m x 2.7m reflector antenna,
used for X-band SAR
Manufacturing
The reflectors are manufactured at Saab’s composite workshop in Linköping, Sweden.
This Center-of-Excellence and the highlevel capabilities of its personnel were first
developed to meet the advanced requirements of high-performance components for
the JAS 39 Gripen combat aircraft and, subsequently, have also been applied to
commercial aircraft components.
The modifications and specific training needed for space component production have
been developed in close cooperation with Saab. Additionally, the facility has access
to very large and accurate milling and measuring machines as well as autoclaves, and
has ample capacity for large production volumes when required.
Feed assemblies
Rosetta dual-frequency high-gain antenna
with dichroic sub-reflector
AMC-23 double antenna
RUAG has fast, very accurate design methods to produce highperformance feeds
and feed components such as corrugated, dual-mode, and rectangular horns,
septum and iris polarizers and OMTs. Redundant active receive feeds for 30 GHz are
available in dimensions covering 1.2 to 5 wavelengths diameters, also with linear or
circular polarisation.
Design precision
RUAG's design tools for both feed horns and reflector systems are very accurate,
allowing direct manufacture of flight hardware from theoretical designs to cut
program costs and delivery time.
Ultra-stable antennas
RUAG Space has developed an extremely stable and accurate CFRP reflector design,
used for the Odin scientific telescope reflector to provide less than 10 μm error,
including thermal deformations, over the 1.1 m main reflector.
Siral extremely accurate radar interferometer antenna
A second application is the RF sensing antenna for the Eutelsat Hotbird 6. This 0.4 m
Ku-band antenna is used to stabilize the satellite within 40 arc seconds irrespective of
solar illumination.
A third application is the ESA Siral altimeter where an interferometer measures the
angle of arrival of a radar signal. The precision required for this is a 0.4 degree phase
accuracy and a 7 arc-second bending of the 1.7 m baseplate. A sunshield is used to
limit thermal gradients.
Generic Gregorian antenna
RUAG Space has developed a generic Gregorian offset-fed antenna featuring a
highly optimized design.
Odin radio astronomy satellite with our
575 GHz Cassegrain antenna
The reflectors and their structure are integrated into a single composite unit. The
concept provides very low mass, low cost, very low thermal deformation and an
extremely accurate surface.
A typical mass for a 1.4 m diameter antenna, including feed assembly and mounts,
is 15-20 kg depending on boundary conditions.
Typical surface accuracy for this size of reflector is 30 μm. All materials and components are standardized and qualified, and can be used for a wide range of dimensions. We consistently utilize our vast experience of ultra-stable reflector manufacture
to achieve superior performance.
RF sensing antenna for fine pointing of satellites
StarOne C1 using our generic Gregorian design
Experience
Technical Data
Application
Frequency
Front-fed symmetrical
Ulysses deep-space probe
Soho deep-space probe
Astra 1K/Hotbird 6
RF sensing antenna
S/X-band
S-band
Ku-band
Front-fed offset
Giotto deep-space probe
SAR Lupe SAR mission
TV-sat/TDF-1
S/X-band
X-band
Ku-band
Cassegrain symmetrical
Columbus KBS data relay
Siral/Cryosat
Ka-band
Ku-band
Cassegrain offset
Tele-X DBS and data
Odin Telescope
Ku-band
up to 575 GHz
Gregorian offset
Sirius 2
Eutelsat W4
AMC-9
Star One C1
AMC-23
Ku-band
Ku-band
Ku-band
Ku-band
Ku-band
Cassegrain symmetrical
with dichroic subreflector
Rosetta
S/X-band
RUAG Space | 405 15 Göteborg | Sweden
Tel. +46 31 735 00 00 | Fax +46 31 735 40 00 | [email protected] | www.ruag.com/space
09.12
RUAG Space has comprehensive experience of most reflector antenna topologies
used today, often including shaped reflectors for optimum performance: