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News Article | March 1, 2017

Innovation Fund Denmark has awarded GomSpace ApS – a subsidiary of GS Sweden AB ("the Company") and the Danish TICRA FOND DKK 5 million to the project "BeamWatch". The project contains development and testing of a nanosatellite prototype designed to predict and measure the quality of communication from more than 400 communication satellites, which form a critical part of the modern global communication infrastructure. The Beam Watch project contributes to ensure that these satellites are not interfering with each other and are only sending out signals in their respective designated areas. The nanosatellite prototype will be equipped with software tools fit to predict what the readings should be, which then will provide the basis for reporting divergence. For more information, please contact: This information was brought to you by Cision,c2201412 The following files are available for download:

Skokic S.,University of Zagreb | Casaletti M.,University of Siena | Maci S.,University of Siena | Sorensen S.B.,Ticra
IEEE Transactions on Antennas and Propagation | Year: 2011

A method is presented for computing aperture radiated fields by means of new conical beams with azimuth phase variation. These beams are generated in a natural way starting from the spectral-domain radiation integral, by expanding the electric field spectrum in the aperture plane in a Fourier series, and by approximating the obtained Fourier series coefficients by a sum of complex exponentials using the generalized pencil-of-function method. This transforms the radiation integral to a simpler form which can be evaluated analytically. Two types of wave objects are derived, both of them arising from the same spectral GPOF process, that possess different properties. Aperture fields obtained via the new approach are successfully compared to those calculated via direct near field integration or asymptotic evaluation. © 2010 IEEE.

Hansen T.B.,Seknion Inc. | Borries O.,TICRA
Radio Science | Year: 2015

A multilevel computation scheme for time-harmonic fields in three dimensions will be formulated with a new Gaussian translation operator that decays exponentially outside a circular cone centered on the line connecting the source and observation groups. This Gaussian translation operator is directional and diagonal with its sharpness determined by a beam parameter. When the beam parameter is set to zero, the Gaussian translation operator reduces to the standard fast multipole method translation operator. The directionality of the Gaussian translation operator makes it possible to reduce the number of plane waves required to achieve a given accuracy. The sampling rate can be determined straightforwardly to achieve any desired accuracy. The use of the computation scheme will be illustrated through a near-field scanning problem where the far-field pattern of a source is determined from near-field measurements with a known probe. Here the Gaussian translation operator improves the condition number of the matrix equation that determines the far-field pattern. The Gaussian translation operator can also be used when the probe pattern is known only in one hemisphere, as is common in practice. Also, the Gaussian translation operator will be used to solve the scattering problem of the perfectly conducting sphere. ©2015. American Geophysical Union. All Rights Reserved.

Borries O.,TICRA | Borries O.,Technical University of Denmark | Meincke P.,TICRA | Jorgensen E.,TICRA | Hansen P.C.,Technical University of Denmark
IEEE Transactions on Antennas and Propagation | Year: 2014

The multi-level fast multipole method (MLFMM) for a higher order (HO) discretization is demonstrated on high-frequency (HF) problems, illustrating for the first time how an efficient MLFMM for HO can be achieved even for very large groups. Applying several novel ideas, beneficial to both lower order and higher order discretizations, results from a low-memory, high-speed MLFMM implementation of a HO hierarchical discretization are shown. These results challenge the general view that the benefits of HO and HF-MLFMM cannot be combined. © 2014 IEEE.

Zhurbenko V.,Technical University of Denmark | Rubaek T.,Chalmers University of Technology | Krozer V.,Goethe University Frankfurt | Meincke P.,TICRA
IET Microwaves, Antennas and Propagation | Year: 2010

An active microwave-imaging system for non-invasive detection of breast cancer based on dedicated hardware is described. Thirty-two transceiving channels are used to measure the amplitude and phase of the scattered fields in the three-dimensional (3D) imaging domain using electronic scanning. The 3D inverse electromagnetic scattering problem is then solved in order to reconstruct the distribution of the complex permittivity in the imaging domain. The dedicated hardware is based on an array architecture allowing for a short acquisition time while maintaining a high sensitivity, which is important for measurement accuracy and reproducibility as well as for patient comfort. The dedicated hardware achieves a receiver noise figure of 2.3 dB at a gain of 97 dB. The operating frequency range is from 0.3 to 3 GHz. The image acquisition time at one frequency is approximately 50 s and an image is created within 2 h using the single-frequency reconstruction algorithm. The performance of the system is illustrated by an analysis of the standard deviations in amplitude and phase of a series of measurements as well as by a simple image reconstruction example. © 2010 The Institution of Engineering and Technology.

Cappellin C.,TICRA | Drioli L.S.,European Space Agency
2016 10th European Conference on Antennas and Propagation, EuCAP 2016 | Year: 2016

The 3D reconstruction algorithm of DIATOOL is applied to the Search and Rescue antennas (SARANT) mounted on the GALILEO satellite, recently measured by the planar near-field scanner of the Hybrid ESA RF and antenna Test Zone (HERTZ) at ESTEC. SARANT operates in L and UHF band, and is one of the many antennas sitting on the GALILEO satellite. The measured field showed a pattern deformation that could be due to the presence of the other antennas on the satellite Earth panel. The purpose of this paper is to investigate this antenna coupling with the DIATOOL software, and compare the results obtained previously by the Insight software, identifying similarities, advantages and limitations of the two algorithms. © 2016 European Association of Antennas and Propagation.

Jorgensen E.,TICRA | Meincke P.,TICRA
2013 7th European Conference on Antennas and Propagation, EuCAP 2013 | Year: 2013

An efficient algorithm for analysis and optimization of rotationally symmetric reflector antennas, possibly including 3D support structures and/or waveguide components, is presented. The high efficiency is obtained by using a domain-decomposition approach where each region of space is characterized independently using a generalized admittance matrix description. The admittance matrices are obtained using circular mode-matching, higher-order 3D MoM, or a newly developed higher-order MoM for bodies of revolution (BoR-MoM). The antenna performance is rigorously evaluated by cascading the admittance matrices, which subsequently allows computation of surface currents or fields in all subdomains. The new algorithm allows fast and accurate analysis and optimization of rotationally symmetric reflectors, even in cases that would normally require a time-consuming 3D solution due to the lack of rotational symmetry. © 2013 EurAAP.

Jorgensen E.,TICRA | Meincke P.,TICRA
IEEE Antennas and Propagation Society, AP-S International Symposium (Digest) | Year: 2012

Rotationally symmetric reflector systems are attractive candidates for realizing compact high-gain antennas with low manufacturing costs, low sidelobes, and low cross polarization. The typical application areas are point-to-point communication links, satellite terminals, and radar systems. These compact systems often employ two reflectors in a classical axially displaced reflector configuration [1], or alternatively, a single reflector with a backward radiating hat feed [2] or splash-plate feed [3]. A common feature of these compact systems is that they include a very tight integration of feed, subreflector, dielectric support structure, and main reflector, which leads to a resonant structure that cannot be analyzed and designed using ray-optical methods. Instead, a full-wave model is needed to analyze the performance of the system with sufficient accuracy and consequently, the full-wave model is also needed when numerically optimizing the antenna performance. Commercially available software for general 3D problems lead to prohibitively long run-times that do not allow numerical optimization. Instead, the rotational symmetry of the structure has been used to formulate the Body-of-Revolution Method of Moments (BoR-MoM) [4], including various formulations for composite metallic/dielectric structures [5]. The MoM problem in [4] was discretized using triangular basis functions and this formulation has been inherited by most later works, including [5]. This low-order discretization typically requires 15 unknowns per wavelength to achieve accurate results, leading to a typical analysis time of 30-60 seconds per frequency for a compact hat-feed antenna. This analysis speed is sufficient for many purposes, but not for full optimization of the combined system including the surface shape of the main reflector, the features of the feeding waveguide, the shape of the dielectric support, and the fine details on the feed hat or the subreflector. © 2012 IEICE.

Viskum H.-H.,TICRA
IEEE Antennas and Propagation Society, AP-S International Symposium (Digest) | Year: 2013

A fast and accurate approach to designing horns and reflectors is implemented in the CHAMP code. The paper presents examples of designs, including shaped reflectors and a horn with a dielectric lens. © 2013 IEEE.

Zhou M.,TICRA | Sorensen S.B.,TICRA
2016 10th European Conference on Antennas and Propagation, EuCAP 2016 | Year: 2016

This paper describes a reflectarray concept that can produce a full dual-band (transmit/receive) multiple spot beam coverage in Ka-band using only two main apertures while maintaining single-feed-per-beam operation. The proposed concept combines the capabilities of the reflectarray and a parabolic surface, enabling the antenna to radiate more than one beam types in the typical 4-color frequency polarization re-use scheme. Preliminary results using single-band array elements are presented and confirm the potential of the proposed concept. © 2016 European Association of Antennas and Propagation.

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