The Antenna Laboratory, through its several facilities and with over 30 years of existence, provides state-of-the-art measurement services to ESA projects and external customers and explores and develops new measurement techniques.
The Antenna Laboratory provides testing capabilities for antennas and payloads, including radiation pattern measurement, absolute gain, phase centre determination, group delay and any other end-to-end payload- or platform-radiated signal across a frequency range between a few hundred MHz to 5 THz. Some of these capabilities are available under various environmental conditions, in order to verify antenna and radiated payload performance in flight conditions.
The Antenna Laboratory provides support to both ESA projects and external customers – including small- to medium-sized companies lacking access to comparable private-sector facilities – needing to assess new antenna designs and techniques and to qualify designs for flight. These have included some of ESA’s largest flight hardware.
The lab has combined, in the same anechoic room, a Compact Payload Test Range (CPTR) and a Near Field Range (NFR) capable of handling test objects up to 5000 kg. Their purpose is to verify in-orbit performance of antennas, payloads and complete satellites with complex antenna farms.
The CPTR is a ‘compensated’ compact range, suitable for testing antennas and payloads in far-field conditions. Its compensated dual-reflector design allows accurate measurements of payloads employing frequency and polarisation re-use to be performed.
The Near Field Range consists of an inverted-T planar scanner in combination with a heavy duty positioning system for the ‘device under test’ (DUT). For planar scanning, the DUT does not move and can be positioned on its own support (e.g. multi-purpose trolley) if required. For spherical and cylindrical near-field scanning, the theta-phi rotation is performed in a roll-over-azimuth configuration. In spherical near-field mode, tests have been successfully performed down to 140 MHz.
Planar scan range (m)
10.10X8.5 (w X h)
Freq. Range (GHz)
Scanning Speed (mm/s)
Up to 1000
Planarity on total area (mm)
± 0.1 RMS Total
Testing in various temperature conditions
Plane Wave Zone
[m] 5 x 7 x 5 (w x l x h)
Freq. Range [GHZ]
3.4 - 25.0
Amplitude ripple [dB]
±0.2 @ X-band
Phase ripple [degrees]
±4 @ X-band
Testing in various temperature conditions
The Hertz facility has all needed infrastructure support to host complex payloads and satellites, including process cooling water, compressed air, 3-Phase 63-Amp UPS, and ‘clean earth’ grounding.
The CATR, a dual parabolic-cylindrical compact range, is dedicated to testing small- to medium-size antennas and instruments up to 1.2m diameter in a range of 4-110GHz. It is perfectly suited for the accurate testing of the new generation of communications antennas and feeds in Ka-, Q-, V- and W-band.
Is also possible to perform spherical near-field antenna testing in a frequency range down to 1 GHz inside the same anechoic room. This allows for the accurate measurement of full-sphere antenna patterns and gains. In addition, this configuration can also be used for the determination of the 3D phase centre and antenna radiated group delay with high accuracy.
The Scatterometer is a quasi-optical free-space RF measurement test bench that, when combined with a network analyser and dedicated analysis software, provides a powerful measurement tool for the determination of complex material properties. It allows the characterisation of dielectrics, ferrites, reflective surfaces and a variety of printed structures, such as FSS, CPSS, half-wave plates and lenses. The set-up is installed in a controlled clean-room environment ensuring adequate conditions for flight hardware testing.
The main advantage of this system is the ability of measuring samples with high absorption or thickness. Co-polar and cross-polar components of the transmission and reflection properties of the samples under test can be determined by using high-performance corrugated horns, grids and refocusing mirrors. In addition, a periscope-based design allows state-of-the-art measurement of the scattering properties of materials over a wide angular range.
The Microwave Material RF Characterisation Free Space test facility comprises two corrugated feeds and grids with collimating elliptical mirrors focused at the sample position. The set-up is used in conjunction with the Compact Antenna Test Range positioner. It allows polarisation measurements in transmission and reflection configuration, both monostatic and bistatic.
This facility enables the characterisation of materials for antenna radomes, reflectors and electromagnetic band-gap structures, as well as frequency/polarisation selective surfaces (FSS). In addition, reflection measurements can be performed over a wide temperature range, up to 500°C.
A pair of horns for each frequency band is either directly connected to the network analyser (8-50 GHz) or to solid-state frequency extenders based on multipliers and mixers (50-110 GHz).
The Menlo Time Domain Spectrometer (TDS) system, allows for the measurement and imaging of samples up to 6 THz. This increase in frequency range will be required for future science and Earth observations missions. All facilities can be encased in a nitrogen tent, to remove any atmospheric effects.