Lars Jacob Foged was born in Viborg, Denmark in 1966. He received his B.Sc from Aarhus Teknikum, Denmark in 1988 and M.Sc. in Electrical Engineering from California Institute of Technology, USA in 1990. He became a “graduate trainee” of the European Space Agency, ESTEC in the Netherlands and spent the following ten years designing antennas for high performance communication and navigation satellites. In 2001, he joined SATIMO and founded the branch office in Italy. Since then, he has held different technical leadership positions in SATIMO and later Microwave Vision Group. He is currently the scientific director of Microwave Vision Group and associate director of Microwave Vision Italy.
27th Annual Meeting and Symposium of the Antenna Measurement Techniques Association (AMTA 2005) | 27th Annual Meeting and Symposium of the Antenna Measurement Techniques Association (AMTA 2005) | 30/10/2005 - 04/11/2005 | Newport, Rhode Island, EE.UU, 2005
Proceedings of the 2012 IEEE International Symposium on Antennas and Propagation, 2012
ABSTRACT The development and initial discussion of a reference MIMO 2×2 antenna concept has been ... more ABSTRACT The development and initial discussion of a reference MIMO 2×2 antenna concept has been presented in [1]. The reference antenna concept has been created to eliminate the uncertainties linked to the unknown antenna performance of the few LTE MIMO 2×2 reference devices or golden standards currently available for evaluating radiated data throughput measurement methodologies and test facilities. The proposed concept is based on simple antennas with a well-known Figure of Merit (FoM) and controllable performance. In this paper we present the recent developments on the antenna concept and report on the first measured performance at uniform incoming power distribution, figures and correlations between different measurement labs.
In classic probe-corrected spherical NF measurements, one of the main concerns is the probe [1], ... more In classic probe-corrected spherical NF measurements, one of the main concerns is the probe [1], [2], [3]. Standard NF-FF transformation software applies probe correction with the assumption that the probe pattern behaves with μ=±1 azimuthal dependence. In reality, any physically realizable probe is just an approximation to this ideal case. Probe excitation errors, finite manufacturing tolerances and probe interaction with the mounting interface and absorbers are examples of uncertainties that can lead to presence of higherorder spherical modes in the probe pattern [4], [5]. Although probe correction techniques for high-order probes are feasible [6], they are highly demanding in terms of implementation complexity as well as in terms of calibration and post-processing time. In this paper, a new OMJ designed entirely in waveguide and capable of covering more than an octave bandwidth is presented. The excitation purity of the balanced feeding is limited only by the manufacturing accura...
The inverse source or equivalent current/source method (EQC), [1]-[7], based on discretization of... more The inverse source or equivalent current/source method (EQC), [1]-[7], based on discretization of integral equations has attracted considerable attention due to a host of promising applications in antenna design and diagnostics. This method offers a greater generality and flexibility since it allows reconstructing sources on arbitrary 3-D surfaces enclosing the antenna under test (AUT). Indeed the equivalent source approach is a true 3D approach as opposed to traditional methods based on plane wave expansion using hemispherical field information. This method is therefore highly suitable for diagnostics on low and medium directivity antenna and even allows the possibility to identify and isolate unwanted effects close to the antenna. In this paper the measurement diagnostics capabilities of the tool are used for detecting possible electrical and/or mechanical defects on the antennas with particular attention to array antennas measured in different measurement scan ranges.
This paper reports the findings of a comparative investigation of two versatile echo suppression ... more This paper reports the findings of a comparative investigation of two versatile echo suppression techniques applicable to general antenna near field measurement scenarios with echoes of unknown origin. Both techniques are based on spatial filtering of the measured field taking advantage of the apriori knowledge of the antenna size and can be applied to near field measurements in any canonical scan configuration. The first technique takes advantages of the spatial filtering properties of the spherical waves expansion of the measured field. The second method is based on the reconstruction of equivalent currents and implements the spatial filtering as a direct consequence of the selected size and shape of the reconstruction surface. The benefit of using redundant data in both techniques as a mean to achieve further echo reduction in spherical near field scan geometry is examined with particular attention. The investigation has been accomplished with measured data on a SATIMO wideband h...
The spherical near-field antenna measurement system StarLab has evolved to cover the entire frequ... more The spherical near-field antenna measurement system StarLab has evolved to cover the entire frequency band from 800MHz to 18GHz [1, 2, 3]. The system is based on probe array technology and the Advanced Modulated Scattering Technique (A-MST) [4, 5]. The StarLab system offers the speed advantages of a probe array, while the mechanical rotation in elevation allows for unlimited angular resolution over the full 3D sphere. By adding a linear scanner, the StarLab system can be converted to a compact cylindrical near field measurement system. This system is particularly well-suited for measurements of base stations and other sectorial type array antennas often used in radar applications. This paper describes the innovative design aspects of the StarLab as a cylindrical near-field measurement system. The system validation testing has been performed using the inverse source technique [9-11]. Measurement of radiation patterns are discussed with particular attention to radar antennas.
2013 IEEE Antennas and Propagation Society International Symposium (APSURSI), 2013
ABSTRACT Nowadays, the final RF functional verification has to be performed on the integrated sat... more ABSTRACT Nowadays, the final RF functional verification has to be performed on the integrated satellite due to the increasing complexity and stringent performance in RF instruments and payloads. To reduce the global time and cost of future Antenna Integration and Test Verification (AIV/AIT) it needs to develop advanced test methodologies. This paper shows the results of a functional testing solution for RF end-to-end antenna testing. The approach proposed is based on structured use of existing measurement capabilities and advanced numerical modeling tools. The scope of this activity is to show the possibility to achieve accurate and fast measurement results using a radical measurement under sampling with respect to the conventional Nyquist criteria.
ABSTRACT The spherical near-field antenna measurement system StarLab has evolved to cover the ent... more ABSTRACT The spherical near-field antenna measurement system StarLab has evolved to cover the entire frequency band from 800MHz to 18GHz [1, 2, 3]. The system is based on patented probe array technology and the Advanced Modulated Scattering Technique (A-MST) [4, 5]. The StarLab system offers the speed advantages of a probe array, while the mechanical rotation in elevation allows for unlimited angular resolution over the full 3D sphere. By adding a linear scanner, the StarLab system can be converted to a compact cylindrical near field measurement system, as shown in Figure 1. This system is particularly well-suited for measurements of base stationsand other sectorial type array antennas. This paper describes the innovative design aspects of the StarLab portable antenna measurement system, with emphasis on the cylindrical near-field measurement capabilities. The system validation testing has been performed using the inverse source technique [9-11] and with comparative measurement campaigns, including both multiprobe and other traditional (single probe) measurement facilities.
2011 IEEE International Symposium on Antennas and Propagation (APSURSI), 2011
... [3] MA Francavilla, J .L. Araque Quijano, G. Vecchi, A. Giacomini , L .J. Foged “Antenna diag... more ... [3] MA Francavilla, J .L. Araque Quijano, G. Vecchi, A. Giacomini , L .J. Foged “Antenna diagnostics for low and medium directivity antennas based on equivalent current approach” AMTA, Salt Lake City, November 2009. ... APSURSI '09. IEEE, June 2009. ...
2013 IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems (COMCAS 2013), 2013
ABSTRACT The equivalent radiating current technique (EQC) is based on an integral equation formul... more ABSTRACT The equivalent radiating current technique (EQC) is based on an integral equation formulation of the inverse source problem upon rigorous application of the equivalence principle. From the measured near or far field data it allows the accurate determination of the equivalent radiating sources on an arbitrary 3-D closed surface enclosing the Antenna Under Test (AUT). The main advantage of the integral equation formulation with respect to wave expansion techniques is its true geometry-independence both for the radiator in examination and the measurement range. The equivalent current technique is highly applicable in the testing, validation and diagnostics of antenna arrays and radars. Indeed, the visualization of the equivalent radiating currents on a surface conformal to the physical shape of the antenna is particularly useful to understand multi element array functioning and facilitate design improvements. This communication discuss different applications of the EQC technique in the testing of these antennas.
2012 6th European Conference on Antennas and Propagation (EUCAP), 2012
ABSTRACT This paper reports on the preliminary results in functional testing solutions for RF end... more ABSTRACT This paper reports on the preliminary results in functional testing solutions for RF end-to-end antenna testing. The proposed approach is based on the intelligent and innovative use of existing measurement capabilities and advanced numerical modeling tools. The scope of the activity is to demonstrate through the implementation of a demonstrator and measurement on suitable hardware the possibility to achieve accurate and fast measurement results using a radical measurement under-sampling with respect to the conventional Nyquist criteria.
Proceedings of the 2012 IEEE International Symposium on Antennas and Propagation, 2012
ABSTRACT This paper presents an investigation of a new technique for the accurate determination o... more ABSTRACT This paper presents an investigation of a new technique for the accurate determination of the full sphere pattern of an antenna from truncated spherical near field measurements. The approach was first described and is based on determining a set of equivalent currents that radiate the same pattern in the known area and thus extrapolate the unknown fields in the truncated area. The study is performed on actual measured near-field data to investigate the effectiveness of the technique in realistic spherical near field antenna measurement scenarios.
IEEE Transactions on Antennas and Propagation, 2015
ABSTRACT The ground-based automatic identification system (AIS) is a coastal tracking and messagi... more ABSTRACT The ground-based automatic identification system (AIS) is a coastal tracking and messaging system used by vessels for maritime traffic monitoring. The European SAT-AIS initiative aims at providing a space-based complementary system to extend the range of the existing AIS to high seas via very high frequency (VHF) satellite constellation. The AIS Miniaturized Antenna (AISMAN) activity concentrates on the development of a VHF array antenna for minisatellite platforms in low Earth orbit. Array element volume minimization and mass reduction are considered performance drivers due to the in-orbit array deployment and satellite mass requirements. Artificial magnetic materials (AMMs) have been chosen as design concept of the baseline array element due to the significant size reduction they can offer. Further technical solutions, such as slotted ground plane, combined with AMM, have allowed for an outstanding profile reduction, while preserving high radiation efficiency and low back radiation. Innovative testing methodologies have been specifically developed to handle truncation errors and echo signals while performing radiation pattern measurement of the array on a full-scale mockup platform in a hemispherical automotive near field (NF) range. This paper discusses the design of array elements, from breadboard to engineering model (TRL4), manufacturing and validation campaigns at single element and array level.
... [6] MA Francavilla, J .L. Araque Quijano, G. Vecchi, A. Giacomini , L .J. Foged “Antenna diag... more ... [6] MA Francavilla, J .L. Araque Quijano, G. Vecchi, A. Giacomini , L .J. Foged “Antenna diagnostics for low and medium directivity antennas based on equivalent current approach” AMTA, Salt Lake City, November 2009. ... APSURSI '09. IEEE, June 2009. ...
27th Annual Meeting and Symposium of the Antenna Measurement Techniques Association (AMTA 2005) | 27th Annual Meeting and Symposium of the Antenna Measurement Techniques Association (AMTA 2005) | 30/10/2005 - 04/11/2005 | Newport, Rhode Island, EE.UU, 2005
Proceedings of the 2012 IEEE International Symposium on Antennas and Propagation, 2012
ABSTRACT The development and initial discussion of a reference MIMO 2×2 antenna concept has been ... more ABSTRACT The development and initial discussion of a reference MIMO 2×2 antenna concept has been presented in [1]. The reference antenna concept has been created to eliminate the uncertainties linked to the unknown antenna performance of the few LTE MIMO 2×2 reference devices or golden standards currently available for evaluating radiated data throughput measurement methodologies and test facilities. The proposed concept is based on simple antennas with a well-known Figure of Merit (FoM) and controllable performance. In this paper we present the recent developments on the antenna concept and report on the first measured performance at uniform incoming power distribution, figures and correlations between different measurement labs.
In classic probe-corrected spherical NF measurements, one of the main concerns is the probe [1], ... more In classic probe-corrected spherical NF measurements, one of the main concerns is the probe [1], [2], [3]. Standard NF-FF transformation software applies probe correction with the assumption that the probe pattern behaves with μ=±1 azimuthal dependence. In reality, any physically realizable probe is just an approximation to this ideal case. Probe excitation errors, finite manufacturing tolerances and probe interaction with the mounting interface and absorbers are examples of uncertainties that can lead to presence of higherorder spherical modes in the probe pattern [4], [5]. Although probe correction techniques for high-order probes are feasible [6], they are highly demanding in terms of implementation complexity as well as in terms of calibration and post-processing time. In this paper, a new OMJ designed entirely in waveguide and capable of covering more than an octave bandwidth is presented. The excitation purity of the balanced feeding is limited only by the manufacturing accura...
The inverse source or equivalent current/source method (EQC), [1]-[7], based on discretization of... more The inverse source or equivalent current/source method (EQC), [1]-[7], based on discretization of integral equations has attracted considerable attention due to a host of promising applications in antenna design and diagnostics. This method offers a greater generality and flexibility since it allows reconstructing sources on arbitrary 3-D surfaces enclosing the antenna under test (AUT). Indeed the equivalent source approach is a true 3D approach as opposed to traditional methods based on plane wave expansion using hemispherical field information. This method is therefore highly suitable for diagnostics on low and medium directivity antenna and even allows the possibility to identify and isolate unwanted effects close to the antenna. In this paper the measurement diagnostics capabilities of the tool are used for detecting possible electrical and/or mechanical defects on the antennas with particular attention to array antennas measured in different measurement scan ranges.
This paper reports the findings of a comparative investigation of two versatile echo suppression ... more This paper reports the findings of a comparative investigation of two versatile echo suppression techniques applicable to general antenna near field measurement scenarios with echoes of unknown origin. Both techniques are based on spatial filtering of the measured field taking advantage of the apriori knowledge of the antenna size and can be applied to near field measurements in any canonical scan configuration. The first technique takes advantages of the spatial filtering properties of the spherical waves expansion of the measured field. The second method is based on the reconstruction of equivalent currents and implements the spatial filtering as a direct consequence of the selected size and shape of the reconstruction surface. The benefit of using redundant data in both techniques as a mean to achieve further echo reduction in spherical near field scan geometry is examined with particular attention. The investigation has been accomplished with measured data on a SATIMO wideband h...
The spherical near-field antenna measurement system StarLab has evolved to cover the entire frequ... more The spherical near-field antenna measurement system StarLab has evolved to cover the entire frequency band from 800MHz to 18GHz [1, 2, 3]. The system is based on probe array technology and the Advanced Modulated Scattering Technique (A-MST) [4, 5]. The StarLab system offers the speed advantages of a probe array, while the mechanical rotation in elevation allows for unlimited angular resolution over the full 3D sphere. By adding a linear scanner, the StarLab system can be converted to a compact cylindrical near field measurement system. This system is particularly well-suited for measurements of base stations and other sectorial type array antennas often used in radar applications. This paper describes the innovative design aspects of the StarLab as a cylindrical near-field measurement system. The system validation testing has been performed using the inverse source technique [9-11]. Measurement of radiation patterns are discussed with particular attention to radar antennas.
2013 IEEE Antennas and Propagation Society International Symposium (APSURSI), 2013
ABSTRACT Nowadays, the final RF functional verification has to be performed on the integrated sat... more ABSTRACT Nowadays, the final RF functional verification has to be performed on the integrated satellite due to the increasing complexity and stringent performance in RF instruments and payloads. To reduce the global time and cost of future Antenna Integration and Test Verification (AIV/AIT) it needs to develop advanced test methodologies. This paper shows the results of a functional testing solution for RF end-to-end antenna testing. The approach proposed is based on structured use of existing measurement capabilities and advanced numerical modeling tools. The scope of this activity is to show the possibility to achieve accurate and fast measurement results using a radical measurement under sampling with respect to the conventional Nyquist criteria.
ABSTRACT The spherical near-field antenna measurement system StarLab has evolved to cover the ent... more ABSTRACT The spherical near-field antenna measurement system StarLab has evolved to cover the entire frequency band from 800MHz to 18GHz [1, 2, 3]. The system is based on patented probe array technology and the Advanced Modulated Scattering Technique (A-MST) [4, 5]. The StarLab system offers the speed advantages of a probe array, while the mechanical rotation in elevation allows for unlimited angular resolution over the full 3D sphere. By adding a linear scanner, the StarLab system can be converted to a compact cylindrical near field measurement system, as shown in Figure 1. This system is particularly well-suited for measurements of base stationsand other sectorial type array antennas. This paper describes the innovative design aspects of the StarLab portable antenna measurement system, with emphasis on the cylindrical near-field measurement capabilities. The system validation testing has been performed using the inverse source technique [9-11] and with comparative measurement campaigns, including both multiprobe and other traditional (single probe) measurement facilities.
2011 IEEE International Symposium on Antennas and Propagation (APSURSI), 2011
... [3] MA Francavilla, J .L. Araque Quijano, G. Vecchi, A. Giacomini , L .J. Foged “Antenna diag... more ... [3] MA Francavilla, J .L. Araque Quijano, G. Vecchi, A. Giacomini , L .J. Foged “Antenna diagnostics for low and medium directivity antennas based on equivalent current approach” AMTA, Salt Lake City, November 2009. ... APSURSI '09. IEEE, June 2009. ...
2013 IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems (COMCAS 2013), 2013
ABSTRACT The equivalent radiating current technique (EQC) is based on an integral equation formul... more ABSTRACT The equivalent radiating current technique (EQC) is based on an integral equation formulation of the inverse source problem upon rigorous application of the equivalence principle. From the measured near or far field data it allows the accurate determination of the equivalent radiating sources on an arbitrary 3-D closed surface enclosing the Antenna Under Test (AUT). The main advantage of the integral equation formulation with respect to wave expansion techniques is its true geometry-independence both for the radiator in examination and the measurement range. The equivalent current technique is highly applicable in the testing, validation and diagnostics of antenna arrays and radars. Indeed, the visualization of the equivalent radiating currents on a surface conformal to the physical shape of the antenna is particularly useful to understand multi element array functioning and facilitate design improvements. This communication discuss different applications of the EQC technique in the testing of these antennas.
2012 6th European Conference on Antennas and Propagation (EUCAP), 2012
ABSTRACT This paper reports on the preliminary results in functional testing solutions for RF end... more ABSTRACT This paper reports on the preliminary results in functional testing solutions for RF end-to-end antenna testing. The proposed approach is based on the intelligent and innovative use of existing measurement capabilities and advanced numerical modeling tools. The scope of the activity is to demonstrate through the implementation of a demonstrator and measurement on suitable hardware the possibility to achieve accurate and fast measurement results using a radical measurement under-sampling with respect to the conventional Nyquist criteria.
Proceedings of the 2012 IEEE International Symposium on Antennas and Propagation, 2012
ABSTRACT This paper presents an investigation of a new technique for the accurate determination o... more ABSTRACT This paper presents an investigation of a new technique for the accurate determination of the full sphere pattern of an antenna from truncated spherical near field measurements. The approach was first described and is based on determining a set of equivalent currents that radiate the same pattern in the known area and thus extrapolate the unknown fields in the truncated area. The study is performed on actual measured near-field data to investigate the effectiveness of the technique in realistic spherical near field antenna measurement scenarios.
IEEE Transactions on Antennas and Propagation, 2015
ABSTRACT The ground-based automatic identification system (AIS) is a coastal tracking and messagi... more ABSTRACT The ground-based automatic identification system (AIS) is a coastal tracking and messaging system used by vessels for maritime traffic monitoring. The European SAT-AIS initiative aims at providing a space-based complementary system to extend the range of the existing AIS to high seas via very high frequency (VHF) satellite constellation. The AIS Miniaturized Antenna (AISMAN) activity concentrates on the development of a VHF array antenna for minisatellite platforms in low Earth orbit. Array element volume minimization and mass reduction are considered performance drivers due to the in-orbit array deployment and satellite mass requirements. Artificial magnetic materials (AMMs) have been chosen as design concept of the baseline array element due to the significant size reduction they can offer. Further technical solutions, such as slotted ground plane, combined with AMM, have allowed for an outstanding profile reduction, while preserving high radiation efficiency and low back radiation. Innovative testing methodologies have been specifically developed to handle truncation errors and echo signals while performing radiation pattern measurement of the array on a full-scale mockup platform in a hemispherical automotive near field (NF) range. This paper discusses the design of array elements, from breadboard to engineering model (TRL4), manufacturing and validation campaigns at single element and array level.
... [6] MA Francavilla, J .L. Araque Quijano, G. Vecchi, A. Giacomini , L .J. Foged “Antenna diag... more ... [6] MA Francavilla, J .L. Araque Quijano, G. Vecchi, A. Giacomini , L .J. Foged “Antenna diagnostics for low and medium directivity antennas based on equivalent current approach” AMTA, Salt Lake City, November 2009. ... APSURSI '09. IEEE, June 2009. ...
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