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  • 1.
    Carlsson, Jan
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    A method of moments solution of a 2D reverberation chamber using G1DMULT and asymptotic extraction2004Ingår i: IEEE AP-S International Symposium and URSI Science Meeting,, 2004, , s. 1323-1327Konferensbidrag (Refereegranskat)
  • 2.
    Carlsson, Jan
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Analysis and Optimization of Multi-Port Antennas by Using Circuit Simulation and Embedded Element Patterns from Full-Wave Simulation2008Konferensbidrag (Refereegranskat)
  • 3.
    Carlsson, Jan
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Method for Circuit based Optimizations of Radiation Characteristics of Multi-Port antennas.2008Ingår i: GigaHertz2008 Symposium, 2008Konferensbidrag (Övrigt vetenskapligt)
  • 4.
    Carlsson, Jan
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlberg, Ulf
    Kildal, Per-Simon
    Signaler och System.
    Comparison of different numerical modeling techniques for reverberation chamber: Initial 2D study2004Ingår i: IEEE AP-S International Symposium and URSI Science Meeting,, 2004, , s. 1511-1515Konferensbidrag (Refereegranskat)
  • 5.
    Carlsson, Jan
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Johansson, Andreas
    Lund University, Sweden.
    Validation of shielding effectiveness measurement method using nested reverberation chambers by comparison with aperture theory2012Ingår i: International Symposium on Electromagnetic Compatibility, EMC EUROPE 2012, 2012, , s. 6396716artikel-id 6396716Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we revisit existing methods for measuring the shielding effectiveness of material samples using nested reverberation chambers. These methods have the advantage of exposing the sample with a more realistic environment than other methods that are based on single plane wave excitation. That is, in the reverberation chamber the sample is exposed to fields with different incidence directions and polarizations resulting in that the average shielding effectiveness can be measured. We show by comparison with aperture theory that the measured shielding effectiveness corresponds to the theoretical value. We show also by measurements that a corrugation or choke on the periphery of an aperture can be used for increasing the shielding effectiveness for a narrow frequency range.

  • 6.
    Carlsson, Jan
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Kildal, Per-Simon
    A Method of Moments Solution for Wires inside a Reverberation Chamber Using Spectral Domain Techniques and Asymptotic Extraction2005Ingår i: 2005 IEEE EMC International Symposium on Electromagnetic Compatibilit, 2005, , s. 117-122Konferensbidrag (Refereegranskat)
  • 7.
    Condo Neira, Edith
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Elektronik.
    Jan, Carlsson
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Karlsson, Kristian
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Elektronik.
    Erik G., Ström
    Chalmers University of Technology, Sweden.
    Combined LTE and IEEE 802.11p Antenna for Vehicular Applications2015Ingår i: 2015 9th European Conference on Antennas and Propagation (EuCAP), 2015, artikel-id 7228685Konferensbidrag (Refereegranskat)
    Abstract [en]

    Vehicles may contain multiple antennas for different applications. Among all of them, Vehicle-to-Vehicle and Vehicle-to-Infrastructure (V2X) is one of the most recent applications. This new technology focuses on traffic safety and traffic efficiency. In this paper we present a new compact antenna module suitable for vehicular applications. This module could be easily integrated into the rear-spoiler on a vehicle. The module consists of two identical monopoles for V2X applications based on the IEEE 802.11p standard and two identical printed inverted F-antennas for Long-Term Evolution (LTE) communications. The evaluation of the proposed module is done by analyzing the simulated and measured antenna S-parameters, antenna efficiencies, radiation patterns, as well as by calculating the diversity performance. The results show that the antennas are well matched and well isolated for both LTE and V2X and exhibits a radiation pattern close to the desired omnidirectional in the horizontal plane for V2X. The two LTE antennas have radiation patterns that complement each other ensuring an omnidirectional coverage by combination. Furthermore the module presents good radiation efficiency for both LTE and V2X.

  • 8.
    Ji, Yilin
    et al.
    Aalborg University, Denmark.
    Fan, Wei
    Aalborg University, Denmark.
    Nilsson, Mikael
    Volvo Car Corporation, Sweden.
    Hentila, Lassi
    Keysight Technologies Oy, Finland.
    Karlsson, Kristian
    RISE Research Institutes of Sweden, Säkerhet och transport, Fordon och automatisering.
    Tufvesson, Fredrik
    Lund University, Sweden.
    Pedersen, Gert
    Aalborg University, Denmark.
    Virtual Drive Testing Over-the-Air for Vehicular Communications2020Ingår i: IEEE Transactions on Vehicular Technology, ISSN 0018-9545, E-ISSN 1939-9359, Vol. 69, nr 2, s. 1203-1213, artikel-id 8917696Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Multiple-input multiple-output (MIMO) over-the-air (OTA) testing is a standardized procedure to evaluate the performance of MIMO-capable devices such as mobile phones and laptops. With the growth of the vehicle-to-everything (V2X) service, the need for vehicular communication testing is expected to increase significantly. The so-called multi-probe anechoic chamber (MPAC) setup is standardized for MIMO OTA testing. Typically, a test zone of 0.85 wavelength in diameter can be achieved with an 8-probe MPAC setup, which can encompass device-under-test (DUT) of small form factors. However, a test zone of this size may not be large enough to encompass DUTs such as cars. In this article, the sufficient number of OTA probes for the MPAC setup for car testing is investigated with respect to the emulation accuracy. Our investigation shows that the effective antenna distance of the DUT is more critical than its physical dimensions to determine the required number of OTA probes. In addition, throughput measurements are performed under the standard SCME UMa and UMi channel models with the 8-probe MPAC setup and the wireless cable setup, i.e. another standardized testing setup. The results show reasonably good agreement between the two setups for MIMO OTA testing with cars under the standard channel models. 

  • 9.
    Kalaran, Hans
    et al.
    Volvo Gtt, Sweden.
    Karlsson, Kristian
    RISE Research Institutes of Sweden, Säkerhet och transport, Fordon och automatisering.
    Moestam, Robert
    CEVT China-Euro Vehicle Technology, Sweden.
    Bergqvist, Björn
    Volvo Car Corporation, Sweden.
    Rosdalen, Åsa
    Volvo Car Corporation, Sweden.
    Eigenmodes of a Loaded Reverberation Chamber2022Ingår i: IEEE International Symposium on Electromagnetic Compatibility. Volume 2022-September, 2022, Pages 212-215, Institute of Electrical and Electronics Engineers Inc. , 2022, s. 212-215Konferensbidrag (Refereegranskat)
    Abstract [en]

    The analytical solution for a loaded reverberation chamber has been investigated. In consistence with earlier works, it is shown that adding a dielectric (non-absorbing) into the chamber will reduce the eigenfrequency of the chamber. This can be a step toward lowering usable frequency inside the Reverberation Chamber and representing the modes density similarly to an empty chamber.

  • 10.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik. Chalmers University of Technology.
    Embedded element patterns in combination with circuit simulations for multi-port antenna analysis2009Doktorsavhandling, monografi (Övrigt vetenskapligt)
  • 11.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Fler antenner ger effektivare mobiler2005Ingår i: Provning & Forskning, nr 4, s. 4-Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 12.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Modväxlande kammare, EMC-provning, antennmätning och telekommunikation2005Ingår i: E3 Magazine, nr 4, s. 12-13Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 13.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Bergenhem, Carl
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Hedin, Erik
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, Pålitliga system.
    Field measurements of IEEE 802.11p communication in NLOS environments for a platooning application2012Ingår i: 76th IEEE Vehicular Technology Conference, 2012, , s. 6399065artikel-id 6399065Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents results from field measurements on a vehicle-to-vehicle communication system based on IEEE 802.11p. During the measurements the vehicles were moving and there were also moving obstacles located between the transmitting and receiving nodes creating a Non-Line-of-Sight environment. Distance, speed and type of obstacles were varied during the measurements. Both a highway and suburban environment was tested. The tests were focused on packet error rate and consecutive packet loss. The results of the measurements are compared with the communication requirements of a vehicle platooning application which is a novel intelligent transport system application. It implies multiple vehicles tightly following each other in a row. Performance of the application degrades with consecutive packet loss. It is shown that the platooning application is not adequately supported in all measurement scenarios.

  • 14.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Analysis and Optimization of MIMO Capacity by using Circuit Simulation and Embedded Element Patterns from Full-Wave Simulation2011Ingår i: iWAT 2010. Lissabon, Portugal. 2010-03-01--03-03, 2011Konferensbidrag (Refereegranskat)
  • 15.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Circuit Based Optimization of Radiation Characteristics of Single and Multi-Port Antennas2009Konferensbidrag (Refereegranskat)
  • 16.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Circuit Based Optimization of Radiation Characteristics of Single and Multi-Port Antennas2009Ingår i: Radioengineering journal, Vol. 18, nr 4, s. Part 1-Artikel i tidskrift (Refereegranskat)
  • 17.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Non-Foster Networks for Improvement of Radiation Efficiency and Effective Diversity Gain of a Multi-Port Antenna, Antennas and Propagation (EuCAP)2011Ingår i: 2010 Proceedings of the Fourth European Conference. Barcelona. 2010-04-12--04-16, EuCAP , 2011Konferensbidrag (Refereegranskat)
  • 18.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Wideband characterization of fabrics for textile antennas2012Ingår i: Proceedings of 6th European Conference on Antennas and Propagation, EuCAP 2012, 2012, , s. 1358-1361Konferensbidrag (Refereegranskat)
  • 19.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Andersson, Torbjörn E
    Olbäck, Magnus
    Strandberg, Lennart
    Hellgren, Mattias
    Distance Dependent Radiation Patterns in Vehcile-to-Vehicle Communications2015Rapport (Refereegranskat)
    Abstract [en]

    We present a method for repeatable measurements of antennas integrated on vehicles in vehicle-to-vehicle communications. The method can handle vehicles and heavy vehicles and results in distance dependent radiation pattern measurements, or near-field coverage measurements. The method is exemplified with measurement results. Key words: Channel models, radiation pattern, vehicles, V2V, measurement

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 20.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Ankarson, Peter
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Ying, Zhinong
    Lund.
    Combination of Full Wave Simulations and Equivalent Circuit Models in Predicting Coupling between Antenna Element and Nearby Object in Mobile Phone2007Konferensbidrag (Refereegranskat)
  • 21.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Belov, Ilja
    Nilsson, Göran
    Kildal, Per-Simon
    Signaler och System.
    Optimization of antenna diversity gain by combining full-wave and circuit simulations2007Konferensbidrag (Refereegranskat)
  • 22.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Kildal, Per-Simon
    Reverberation Chamber for antenna Measurements: Modeling using Method of Moments, Spectral Domain Techniques and Asymptote Extraction2006Ingår i: IEEE Transactions on Antennas and Propagation, Vol. 54, nr 11, s. 3106-3112Artikel i tidskrift (Övrigt vetenskapligt)
  • 23.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik.
    Olbäck, Magnus
    Volvo, Sweden.
    Vukusic, Tin
    Volvo, Sweden.
    Whiton, Russ
    Volvo, Sweden.
    Wickström, Samuel
    Scania, Sweden.
    Ledfelt, Gunnar
    Scania, Sweden.
    Rogö, Johan
    Kapsch TrafficCom AB, Sweden.
    Utilizing two-ray interference in vehicle-to-vehicle communications2014Ingår i: 8th European Conference on Antennas and Propagation, EuCAP 2014, Institute of Electrical and Electronics Engineers Inc. , 2014, s. 2544-2547, artikel-id 6902339Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents a method for the utilization of radio channels with two-ray propagation properties between vehicles in vehicle-to-vehicle communications. The method uses spatial diversity with antennas separated in the vertical direction to counteract low received levels in regions of destructive interference according to a two-ray path loss model. Results are exemplified with measurements and further analysed with simulations.

  • 24.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Chen, Xiaoming
    Chalmers University of Technology, Sweden.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Skårbratt, Anton
    Bluetest AB, Sweden.
    On OTA test in the presence of doppler spreads in a reverberation chamber2013Ingår i: IEEE Antennas and Wireless Propagation Letters, ISSN 1536-1225, E-ISSN 1548-5757, Vol. 12, s. 886-889Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this letter, over-the-air (OTA) tests of the performance of the IEEE 802.11p radio system are performed in a reverberation chamber (RC) that is equipped with a fast rotating mode stirrer. By varying the speed of the mode stirrer, different levels of Doppler spreads are created, and the 802.11p radio system is tested accordingly. As expected, the Doppler spread affects the package error rate (PER) of the radio system adversely. In addition to measurements, a simple PER model is presented, which sheds some light into the OTA tests.

  • 25.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Chen, Xiaoming
    Kildal, Per-Simon
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Doppler Spread in Reverberation Chamber Predicted From Measurements During Step-Wise Stationary Stirring2011Ingår i: Proceedings of IEEE Antennas and Wireless Propagation Letters, 2011, , s. 497-500Konferensbidrag (Refereegranskat)
  • 26.
    Karlsson, Kristian
    et al.
    RISE Research Institutes of Sweden, Säkerhet och transport, Fordon och automatisering.
    Lundberg, Andreas
    RISE Research Institutes of Sweden, Säkerhet och transport, Fordon och automatisering.
    Arabäck, Niklas
    RISE Research Institutes of Sweden, Säkerhet och transport, Fordon och automatisering.
    Bergqvist, Björn
    Volvo Car Corporation, Sweden.
    Test Level in Reverberation Chamber EMC Immunity Assessment Based on the Quantile to Average Ratio2022Ingår i: IEEE International Symposium on Electromagnetic Compatibility. Volume 2022-September, 2022, Pages 178-182, Institute of Electrical and Electronics Engineers Inc. , 2022, s. 178-182Konferensbidrag (Refereegranskat)
    Abstract [en]

    As more and more advanced electronics are incorporated into devices and vehicles, there is a need to improve and refine the test methods for performance assessment of electromagnetic compatibility. Traditional standards in reverberation chamber electromagnetic compatibility immunity assessment define the test level according to a calibration based on an average of maximum received electrical field probe readings. In this paper, we propose a converging approach based on the average, in combination with an additional offset to generate a quantile defined test level. 

  • 27.
    Karlsson, Kristian
    et al.
    RISE Research Institutes of Sweden, Säkerhet och transport, Fordon och automatisering.
    Moestam, Robert
    CEVT China-Euro Vehicle Technology, Sweden.
    Bergqvist, Björn
    Volvo Car Corporation, Sweden.
    Kalaran, Hans
    Volvo Gtt, Sweden.
    Rosdalen, Åsa
    Volvo Car Corporation, Sweden.
    Electrical Fields in Vehicular Cavities During Reverberation Chamber EMC Immunity Test2022Ingår i: IEEE International Symposium on Electromagnetic Compatibility. Volume 2022-September, 2022, Pages 189-194, Institute of Electrical and Electronics Engineers Inc. , 2022, s. 189-194Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we elaborate on EMC immunity tests in reverberation chambers of full-sized vehicles as well as these products' corresponding electromagnetic susceptibility. It is described how vehicles have regions or volumes (i.e., cavities), with sometimes installed hardware as well as software, which potentially is susceptible to electromagnetic interference, and how these cavities during test have properties (deterministic to ergodic) implying frequency-dependent properties of the electrical fields. Number of degrees of freedom for the electric fields is used to explain the behaviour of EMC, from deterministic coherent resonances and all the way to ergodic regions. 

  • 28.
    Karlsson, Kristian
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Elektronik.
    Toss, Henrik
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Elektronik.
    Costagliola, F.
    Volvo Car Corporation, Sweden.
    Reducing influence from ground reflection during RCS characterization of automotive targets2019Ingår i: 13th European Conference on Antennas and Propagation, EuCAP 2019, Institute of Electrical and Electronics Engineers Inc. , 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Ground reflection is the major contributor to measurement uncertainty in the characterization of Radar Cross-Section (RCS) of automotive targets. In this paper we present a study of the influence of ground reflection on RCS measurements of large targets - such as real vehicles or surrogate objects - performed on flat outdoor test ranges. The influence of ground reflection and several means to reduce this effect are investigated and compared. Results are derived with theoretical formulas and simple models.

  • 29.
    Karlsson, Kristian
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Elektronik.
    Toss, Henrik
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Elektronik.
    Lang, John
    Autoliv, Sweden.
    Costagliola, Francesco
    Volvo Car Corporation, Sweden.
    Zheng, Tian
    Volvo Car Corporation, Sweden.
    Marel, Elias
    Volvo Car Corporation, Sweden.
    HiFi Radar Target: High fidelity soft targets and radar simulation for more efficient testing (real and virtual)2018Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Radarsensorn på 77 GHz är en vital komponent för ADAS (Advanced Driver Assistance System) samt system för autonom körning (AD) tack vare sin förmåga att detektera och följa objekt på avstånd upp till 200 meter. För att säkerställa hög tillförlitlighet hos fordonets funktioner baserade på radarn krävs omfattande tester med mjuka surrogatmål. Radarresponsen hos ett surrogatmål kan dock skilja sig från det för reella mål, vilket i förlängningen kan orsaka oväntade reaktioner från ADAS- och AD-funktioner i verkliga trafiksituationer. Det första projektmålet var därför att utveckla och validera mjuka surrogatmål så att de blir mer realistiska, ett arbete som utfördes i flera steg: referensmål togs fram och verifierades, metoder för on site kalibrering av radarsensorer utvecklades, och slutligen togs metoder fram för karakterisering av radarmålarea (RCS) av stora objekt på testbana (AstaZero, high speed area). Detta resulterade i flera mätuppställningar och mätprocedurer inklusive osäkerhetsanalys. Nu, med förmågan att utföra repeterbara och pålitliga RCS-mätningar, karakteriserandes ett antal reella mål (verkliga bilar) samt surrogatmål och arbetet med att syntetisera radarmålarean hos surrogatmål genomfördes.

    Stark konkurrens inom bilindustrin och behovet av att validera mer och mer komplexa funktioner (inklusive autonom körning) driver utvecklingen av virtuella testmetoder. Möjligheten att testa ADAS eller AD-funktioner tidigt i utvecklingscykeln kommer att spara tid, kostnad och vara en konkurrensfördel. Dock fanns inga verktyg med kapacitet att utvärdera radarsensorn tillsammans med resten av bilens hård- och mjukvara virtuellt tillgängliga före projektet, vilket var orsaken till det andra målet: ett simuleringsverktyg för ADAS/AD-system inklusive simulering av radarn.

    HiFi Radar Target-projektet (diarienr. 2015-04852) var ett FFI-projekt inom programmet Elektronik, programvara och kommunikation. Efter förlängning blev det ett 30-månaders projekt med start 2015-12-31 och slut datum 2018-06-30. Projektet hade en total budget på 15,9 MSEK.2.1

    Mål

    Utvecklingen av radarsystem, en nödvändig sensor för aktiv säkerhet och autonoma fordon, kräver pålitlig och effektiv testning för validering av systemprestanda. Effektiv utveckling kräver att man tidig upptäcker och löser möjliga problem, något som testinfrastrukturen måste stödja. Målet med projektet var därför att möjliggöra effektiv och tillförlitlig verifiering av radarsystem, inklusive ADAS och AD-system som är beroende av radarsensorer, genom:

    • Utveckling samt validering av repeterbara RCS mätmetoder.
    • Utveckling av mer realistiska surrogatmål för säker provning av bilradarsystem.
    • Utveckling av simuleringsverktyg för radarsystem i virtuell miljö.
    • Demonstration av förbättrad verifiering med hjälp av de utvecklade verktygen och metoderna.
    • Stödja internationell standardisering (ISO) i deras arbete för framtida verifiering och kalibrering av surrogatmål.

    Projektresultaten kommer att:

    • Bidra till nollvisionen, det vill säga noll dödliga trafikolyckor.
    • Stärka svensk bilindustris konkurrenskraft i ett globalt perspektiv.
    • Bidra till att utveckla AstaZero till en testplats i världsklass för ADAS och AD system.
    • Ge verktyg och metoder för AD-testning till VCC.

    Resultat och leveranser

    Målen som beskrivits i föregående kapitel har alla (i olika utsträckning) blivit uppfyllda:

    • Utveckling och validering av noggranna och repeterbara RCS mätmetoder: detta mål uppnåddes mycket väl och konsortiet har arbetat internationellt.
    • Utveckling av mer realistiska surrogatmål för säker provning av bilradarsystem: projektet har fått kunskap om vilka egenskaper som påverkar radarresponsen för ett specifikt mål och har förbättrat surrogatmål inklusive den automatiserade mobila plattform som förflyttar surrogatmålen under test.
    • Utveckling av simuleringsverktyg för virtuell testning av radarsystem: verktygskedjan för trafiksimulering av AD och ADAS funktioner hos VCC har uppdaterats med nya realistiska (mätbaserade) klustermodeller för radarmål. För framtida utveckling definierades också ett interface som möjliggör implementering av nya modeller.
    • Demonstration av metoder framtagna i projektet: projektresultat presenterades och demonstrerades vid AstaZero.
    • Stödja internationell standardisering (ISO) i utvecklingen av metoder för framtida verifiering och kalibrering av surrogatmål: projektet har bidragit till arbetet i ISO genom att öka förståelsen för RCS hos riktiga fordon och surrogatmål, definierat representativa egenskaper hos radarmål, tagit fram metoder för repeterbar och noggrann karakterisering, samt tagit fram en osäkerhetsbudget.
    Ladda ner fulltext (pdf)
    fulltext
  • 30.
    Karlsson, Kristian
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Vinter, Jonny
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, Pålitliga system.
    Svahn, Fredrik
    Pre Automotive Cooperative Technologies (PreAct)2011Rapport (Refereegranskat)
  • 31.
    Karlsson, Kristian
    et al.
    RISE Research Institutes of Sweden, Säkerhet och transport, Fordon och automatisering.
    Wersäll, Martin
    RISE Research Institutes of Sweden, Säkerhet och transport, Fordon och automatisering.
    Harrysson, Fredrik
    RISE Research Institutes of Sweden, Säkerhet och transport, Fordon och automatisering.
    Patane Lotback, C. S.
    Volvo, Sweden.
    On the Keyhole Effect in Over-The-Air Testing of Higher Order MIMO Systems2021Ingår i: 15th European Conference on Antennas and Propagation, EuCAP 2021, Institute of Electrical and Electronics Engineers Inc. , 2021Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, the influence of a limited number of radio frequency connections between two Rayleigh fading environments, also known as the keyhole effect, is theoretically investigated for higher-order MIMO systems. It is shown that the effect of a limited number of keyholes is kept stable or is even reduced as the number of keyholes is equal to or larger than the MIMO system order. The results are relevant for over-the-air testing with connected Rayleigh fading systems, such as a channel emulator connected to a reverberation chamber, or a reverberation chamber connected to another reverberation chamber (nested reverberation chambers).

  • 32.
    Larsson, Marcus
    et al.
    Qamcom Research and Technology AB, Sweden; Halmstad University, Sweden.
    Jonsson, Magnus
    Halmstad University, Sweden.
    Warg, Fredrik
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    A Data Age Dependent Broadcast Forwarding Algorithm for Reliable Platooning Applications2016Ingår i: International Journal of Mobile Information Systems, ISSN 1574-017X, E-ISSN 1875-905X, Vol. 2016, artikel-id 7489873Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We propose a broadcast message forwarding algorithm for V2V communication in a platooning scenario for heavy duty trucks. The algorithm utilizes link information, which is piggybacked on the original data packet, to estimate which nodes are best suited to forward the packet. The aim is to reach all nodes in the platoon with as few forward messages as possible in order to avoid channel congestion. The algorithm is evaluated by simulation using real world V2V measurement data as input. We show that the algorithm performs almost as good as two ETSI standardized forwarding algorithms with respect to keeping the data age for the entire platoon at a low level. But when it comes to keeping the message intensity low, our algorithm outperforms the better of the ETSI algorithms by 35%.

    Ladda ner fulltext (pdf)
    fulltext
  • 33. Larsson, Marcus
    et al.
    Warg, Fredrik
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, Pålitliga system.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Jonsson, Magnus
    Evaluation of a Low-Overhead Forwarding Algorithm for Platooning2015Ingår i: Proceedings of the 2015 IEEE International Conference on Vehicular Electronics and Safety (ICVES 2015)., 2015Konferensbidrag (Övrigt vetenskapligt)
  • 34.
    Lehne, Per Hjalmar
    et al.
    Telenor Research, Norway.
    Glazunov, Andrés Alayón
    Chalmers University of Technology, Sweden.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Finding the distribution of users in a cell from smart phone based measurements2016Ingår i: Proceedings of the International Symposium on Wireless Communication Systems, 2016, s. 538-542, artikel-id 7600963Konferensbidrag (Refereegranskat)
    Abstract [en]

    Mobile users are assumed to be positioned within the cell or sector boundaries of the serving cell in the network. Measurements of location done by the smart phones combined with the network layout show differently. There is a significant amount of users which are actually outside the nominal sector boundaries. Knowledge about the statistical location distribution of users inside or outside the serving cell intended coverage may prove valuable in finding more optimal resource management methods. Another application is the development of over-the-air characterization of base station antennas. Distance and directional statistics are shown for samples of relative positions within the cell sectors of a real network using smart phone based measurements. Samples for LTE in 800 and 1800 MHz non-voice usage and 3G at 2100 MHz voice usage is included. The distance distributions show clearly that the usage density rapidly decrease with the distance, and there is a clear confirmation that lower frequencies have longer range, also in terms of usage density. Mean usage distance for 800 MHz is 1.62 km, while for 2100 MHz it is only 580 m. It also shows that 90% of the usage is within 3.47 and 1.35 km for the two cases, respectively. The directional distributions relative to the sector centre direction shows that 80% of the users are within 153 degrees for lowest frequency, and 109 degrees for the highest.

  • 35.
    Nagalapur, K. K.
    et al.
    Chalmers University of Technology, Sweden.
    Ström, E. G.
    Chalmers University of Technology, Sweden.
    Brännström, F.
    Chalmers University of Technology, Sweden.
    Carlsson, J.
    Chalmers University of Technology, Sweden; Provinn AB, Sweden.
    Karlsson, Kristian
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, AstaZero.
    Robust Connectivity With Multiple Directional Antennas for Vehicular Communications2020Ingår i: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 21, nr 12, s. 5305-5315Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For critical vehicular communication services, such as traffic safety and traffic efficiency, it is advisable to design systems with robustness as the main criteria, possibly at the price of reduced peak performance and efficiency. We describe a simple, low-cost method for combining the output of L directional (i.e., not omnidirectional) antennas to the input of a single-port receiver with the aim to guarantee robustness, i.e., to minimize the probability that K consecutive packets arriving from the worst-case angle-of-arrival are decoded incorrectly. To minimize complexity, the combining network does not estimate or use channel state information. The combining network consists of L-1 analog phase shifters whose phases are affine functions of time. For a general Lłe K and when the packet error probability decays exponentially with the received SNR, the optimum slopes of the affine functions can be computed by solving an optimization problem that depends on the antenna far-field functions. We provide analytical solutions for the special case of L=2 and 3 antennas, which turns out to be independent of the antenna far-field functions and placement on a vehicle. In an experimental setup consisting of two monopole antennas mounted on the roof of a Volvo XC90, the proposed combining method is shown to give significant performance gains, compared to using any one of the antennas.

  • 36.
    Nagalapur, Keerthi
    et al.
    Chalmers University of Technology, Sweden.
    Strom, Erik
    Chalmers University of Technology, Sweden.
    Brannstrom, Fredrik
    Chalmers University of Technology, Sweden.
    Carlsson, Jan
    Chalmers University of Technology, Sweden.
    Karlsson, Kristian
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Elektronik.
    A Simple Method for Robust Vehicular Communication with Multiple Nonideal Antennas2018Ingår i: 2018 IEEE MTT-S International Conference on Microwaves for Intelligent Mobility, ICMIM 2018, 2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    For critical vehicular communication services, such as traffic safety and traffic efficiency, it is advisable to design systems with robustness as the main criteria, possibly at the price of reduced peak performance and efficiency. We describe a simple, low-cost method for combining the output of L nonideal (i.e., nonisotropic) antennas to the input signal to a single-port receiver with the aim to guarantee robustness, i.e., to minimize the probability that K consecutive packets arriving from the worst-case angle-of-arrival are decoded incorrectly. To minimize complexity, the combining network does not estimate or use channel state information (complex channel gains, noise levels, etc.). The combining network consists of L -1 analog phase shifters whose phases are affine functions of time. For a general L and the case when the packet error probability decays exponentially with the received SNR, the optimum slopes of the affine functions can be computed by solving an optimization problem that depends on the antenna far field functions. We provide an analytical solution for the special case of L $=2$ antennas, which turns out to be independent of the antenna patterns. In an experimental setup consisting of two monopole antennas mounted on the roof of a Volvo XC90, the proposed combining method is shown to give significant performance gains compared to using just one of the antennas.

  • 37.
    Neira, Edith Condo
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlberg, Ulf
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Carlsson, Jan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Karlsson, Kristian
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Elektronik, EMC.
    Ström, Erik G.
    Chalmers University of Technology, Sweden.
    Evaluation of V2X antenna performance using a multipath simulation tool2014Ingår i: 8th European Conference on Antennas and Propagation, EuCAP 2014, 2014, , s. 2534-2538s. 2534-2538, artikel-id 6902335Konferensbidrag (Refereegranskat)
    Abstract [en]

    Antennas are one of the key components for efficient and reliable vehicular communications systems; especially for safety related applications the antenna performance is crucial. It is therefore important to be able to evaluate the antenna performance under realistic conditions so that the best antenna solution can be selected. In this paper we present a statistical method for evaluating the antenna performance by using the antennas radiation patterns and a multipath simulation tool. The multipath environment is generated by a number of incident waves with a specific angle of arrival distribution, defined by the user. In order to generate voltage samples at the antenna ports many sets of incident waves are generated. This simulates a changing environment as, e.g., when the vehicle is moving. By studying the cumulative distribution functions (CDFs) for the voltage samples we are able to compare the performance for different antenna types, positions on the vehicle, etc. The method is fast and effective and, when applied to typical vehicular propagation environments, the importance of having antennas with radiation patterns capable of covering the whole azimuth plane is demonstrated.

  • 38.
    Patane Lotback, C. S.
    et al.
    Volvo, Sweden.
    Karlsson, Kristian
    RISE Research Institutes of Sweden, Säkerhet och transport, Fordon och automatisering.
    Kildal, M. S.
    RanLOS AB, Sweden.
    Haliti, A.
    Volvo, Sweden.
    Nilsson, M.
    Volvo, Sweden.
    Iustin, R.
    Volvo, Sweden.
    Evaluation of Complete Vehicle Over-The-Air Verification Methods for Multiple-Input Multiple-Output Communication Systems2021Ingår i: 15th European Conference on Antennas and Propagation, EuCAP 2021, Institute of Electrical and Electronics Engineers Inc. , 2021Konferensbidrag (Refereegranskat)
    Abstract [en]

    As more and more advanced wireless technologies are incorporated into vehicles, there is a need to refine the test methods used for assessing the performance. Traditional test setups for multiple-input multiple-output (MIMO) communication systems have been developed for relatively small devices such as handsets and tablets. At the same time, there is a desire to replace vehicular field tests with lab testing, for more efficient and accurate testing. This paper evaluates over-the-air verification methods for MIMO communication systems, which may incorporate vehicle-sized antenna systems and that can be implemented in a lab. Different methods are compared by means of a round robin campaign. The results from the campaign indicate that performance assessment representative to real-world operation can be achieved.

  • 39.
    Toss, Henrik
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Elektronik.
    Karlsson, Kristian
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Elektronik.
    Radar reflectivity spatial profile of 3D surrogate targets and real vehicles2019Ingår i: 13th European Conference on Antennas and Propagation, EuCAP 2019, Institute of Electrical and Electronics Engineers Inc. , 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper a method to find a radar reflectivity spatial profile for comparing 3D surrogate targets with real vehicles is proposed. Utilizing this method, the spatial profile can be acquired using only high-level data from an automotive grade radar. For data within a small angular window at arbitrary aspect angle relative to the target, the proposed method back-projects Radar Cross Section (RCS) detections, to build up a spatial profile. This profile can then be used to evaluate multiple scattering centers on targets, which are important during test of autonomous vehicles and active safety functions. The method is used on measured data from 3D surrogate targets as well as real vehicles, which are presented in the paper.

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