mdh.sePublications
Change search
Refine search result
1 - 15 of 15
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Hozhabri, Melika
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Petrovic, Nikola
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Comparison of UWB Radar Back-Scattering by the Human Torso and a Phantom2018Conference paper (Refereed)
    Abstract [en]

    An Ultra Wide Band(UWB) radar is used to measure the cross section of a human phantom indifferent polarizations of the receiver antenna. The choice of material and shape for the human phantom is discussed. The material used in the experiment(wet sand) dielectric properties measured by a retromodeling technique and then calculated by mixture formulas. The appropriate frequency choice for the application is discussed.

  • 2.
    Hozhabri, Melika
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. IS (Embedded Systems).
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. IS (Embedded Systems).
    Petrovic, Nikola
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. IS (Embedded Systems).
    Study of the Environment Effect by M-Sequence UWB Radar on Detection of a Walking Human2016In: 2016 IEEE Conference on Antenna Measurements & Applications (CAMA) CAMA 2016, 2016, article id 7815740Conference paper (Refereed)
    Abstract [en]

    This paper presents an experimental comparison study of human movement and presence detection in different environments using ultra-wide-band (UWB) M-Sequence radar. The benchmarking measurements are made in an anechoic chamber and repeated in an open office environment. The wave forms of the background noise and scattered amplitudes of a human body are measured and compared. The result is analyzed and discussed. A set of detection algorithms and filters which are developed to track the human movement and presence is presented and the tracking results in these two environments are compared to each other.

  • 3.
    Otterskog, Magnus
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. IS (Embedded Systems).
    Petrovic, Nikola
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. IS (Embedded Systems).
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. IS (Embedded Systems).
    A multi-layered head phantom for microwave investigations of brain hemorrhages2016In: 2016 IEEE Conference on Antenna Measurements & Applications (CAMA) CAMA 2016, Syracuse, United States, 2016, article id 7815764Conference paper (Refereed)
    Abstract [en]

    A head phantom for microwave investigations is developed. It consists of a skull bone with realistic dielectric properties of cancellous and cortical bone. The skull phantom is filled with liquids and semi-solids that dielectrically represent the white/gray matter and blood, respectively.

  • 4.
    Petrovic, Nikola
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Otterskog, Magnus
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Antenna applicator concepts using diffraction phenomena for direct visualization of brain hemorrhages2016In: 2016 IEEE Conference on Antenna Measurements & Applications (CAMA) CAMA 2016, 2016Conference paper (Refereed)
    Abstract [en]

    Direct use of diffraction phenomena at an irregularity in a lossy object such as a head is described. The source is an external magnetic field directed into the skull, creating a circulating current inside the object by which surface waves are avoided. The receiving E-field probe is a 3D resonant structure being selectively sensitive to the desired deflected electric field component from the surface.

  • 5.
    Petrovic, Nikola
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. IS (Embedded Systems).
    Otterskog, Magnus
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. IS (Embedded Systems).
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. IS (Embedded Systems).
    Antenna Applicators and Microwave Fields for Imaging of the Interior of Human Breasts and Heads2016Conference paper (Other academic)
  • 6.
    Petrovic, Nikola
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Otterskog, Magnus
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Breast tumor detection with microwave applicators in open air2017In: 2017 IEEE Conference on Antenna Measurements & Applications (CAMA) CAMA 2017, 2017, p. 272-274Conference paper (Refereed)
    Abstract [en]

    A system for either direct use of diffraction phenomena or indirect use by computational methods for female breast tumor detection is described. The excitation device is a single external non-contacting, sectioned single turn loop, creating an axial magnetic field directed into the breast. A circulating current is created inside it and the diffracted field is directly sensed.

  • 7.
    Petrovic, Nikola
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Otterskog, Magnus
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Breast tumour detection by two microwave antenna principles2017In: Proceedings of the 2017 19th International Conference on Electromagnetics in Advanced Applications, ICEAA 2017, Institute of Electrical and Electronics Engineers Inc. , 2017, p. 1258-1261Conference paper (Refereed)
    Abstract [en]

    A comparison between breast tumour detection with a traditional lossy coupling medium based system and a system without coupling medium is performed, by numerical modelling and experimentally. While a system with lossy coupling medium offers surface wave reduction and protection from surrounding sources and obstacles it also demands good permittivity matching of the coupling medium to the breast tissue under investigation, as well as a high performance measurement system with a dynamic range exceeding 100 dB. The system without coupling medium offers possible direct detection of inhomogeneities with transmission losses of about 50...60 dB. The proposed contacting antenna system however needs further development in order to reduce stray fields and adoption to realistic breast tissue properties.

  • 8.
    Petrovic, Nikola
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Otterskog, Magnus
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Experiments and numerical modelling of contacting antenna applicators at a free space head model2015In: 2015 IEEE International Conference on Antenna Measurements & Applications (CAMA) CAMA 2015, 2015, article id 7428125Conference paper (Refereed)
    Abstract [en]

    Microwave absorbing boluses or similar are impractical, particularly in stroke emergencies, since the creation of surface waves around the head dominating over the internal signal paths is then a problem. The performance of miniaturised ridged waveguide applicators in the frequency interval 1 to 3 GHz designed for the application of breast cancer detection are used in this study, slightly modified, on head models for investigation of disturbing surface waves.

  • 9.
    Petrovic, Nikola
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Otterskog, Magnus
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    QUANTIFICATION OF INHOMOGENEITIES IN OBJECTS BY ELECTROMAGNETIC FIELDS2017Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    A system and method, as well as sub assemblies thereof, for detection of dielectric irregularities/inhomogeneities inside an object under study (OUS) be means of electromagnetic energy are disclosed. The system comprises a loop/cylinder emitter configured to be located close to the OUS with its axis of symmetry directed towards the OUS. A feeding line feeds the emitter with an alternating current at an operating frequency to cause a magnetic field therein, which in turn will induce a propagating electromagnetic field in the OUS. In order to reduce propagating fields outside of the OUS, the circumference of the emitter is smaller than the free-space wavelength corresponding to the operating frequency, and the feeding line has a characteristic impedance that is smaller than 20 Ohm.

  • 10.
    Petrovic, Nikola
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    A Zirconia Cylindrical TM010 Cavity for Permittivity Measurements at 1 GHz2018In: 2018 IEEE CAMA Conference on Antenna Measurement and Applications CAMA 2018, 2018Conference paper (Refereed)
    Abstract [en]

    The most accurate dielectric measurements are made by resonant cavity methods, the circular TM010 type being the simplest and most common. However, an airfilled such cavity at 1 GHz needs to be 250 mm in diameter. There is another problem as well: its limited applicability with very lossy samples, due to a too low Q value. This paper describes the development and properties of a metalized zirconia ceramic cavity for use at about 1 GHz. With its permittivity ε′ = 30 its diameter becomes 40 mm instead of 150 mm for the airfilled version. Additionally and importantly, the dynamic range of the loss factor ε″ is greatly expanded. The calibration procedure using numerical retromodelling is described and a measurement example of a ternary alcohol mixture is carried out. The accuracy is also estimated.

  • 11.
    Petrovic, Nikola
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Overview of microwave based diagnostics for breast tumours and strokes2018In: World Congress on Medical Physics and Biomedical Engineering IUPESM 2018, 2018, no 1Conference paper (Refereed)
  • 12.
    Petrovic, Nikola
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Tomasic, Ivan
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Lindén, Maria
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Risman, Per Olov
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Detection of Human Bodypart Abnormalities by Microwaves – A New Approach2019In: 42nd International Convention on Information and Communication Technology, Electronics and Microelectronics MIPRO 2019, 2019, p. 270-274Conference paper (Refereed)
    Abstract [en]

    We present modified antenna-like devices - applicators - for direct detection of internal inhomogeneities such as breast tumours and brain haemorrhages, at a frequency about 1 GHz. This direct detection provides the possibility of using a simple microwave generator and simple rectification and position registration of the received signals. Direct readouts are thus possible, without any massive computing resources as with tomographic imaging. The transmitting applicator is non-contacting and in free air close to the object. It generates an essentially quasistatic axial magnetic field which induces a circular electric field in the tissue. The receiving 3D contacting applicator contains a high-permittivity ceramic and is resonant. Its mode field provides the desired polarisation sensitivity and filters out the main electric field. The overall system sensitivity for detection of internal inhomogeneities is accomplished by optimised use of the orthogonality of the primary magnetic, induced electric, and diffracted electric fields. When developments are completed, the system will replace or complement existing commercial technologies at a low cost.

  • 13.
    Risman, Per Olov
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Otterskog, Magnus
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Petrovic, Nikola
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    MICROWAVE ANTENNA APPLICATOR2015Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    A new and comparatively small type of open-ended microwave applicators has been disclosed. They are for example suitable for transmission into and reception from contacting objects such as protruding human bodyparts for inhomogeneity detection by tomographic methods. The applicators according to the invention are of the dielectric-filled open-ended ridged rectangular TE10 type, with an insert filling the ridge and having a higher permittivity than the surrounding space. The shape of the insert can be as a frustrum pyramid towards the opening. The overall design promotes narrow beamwidths and minimises nearfields and surface wave excitation.

  • 14.
    Risman, Per Olov
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Otterskog, Magnus
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Petrovic, Nikola
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. IS (Embedded Systems).
    Översikt av mikrovågsbaserad diagnostik för brösttumörer och stroke2017In: Medicinteknikdagarna 2017 MTD 2017, Västerås, Sweden, 2017Conference paper (Refereed)
    Abstract [en]

    Forskningsområdet mikrovågsavbildning inom medicinen introducerades redan på 1980-talet av Larsen och Jacobi [1]. Objektet var en hundnjure nedsänkt i en mikrovågsabsorberande vätska (bolus) för att undvika störningar och direkt koppling mellan de två roterande antennmatriserna. Man fann att intressant mikrovågskontrastverkan kunde uppnås i biologiska objekt. Fördelar jämfört med mammografi är ex.vis att strålningen är helt ofarlig och att man kan »se» närmare revbenen. Nackdelen är att detaljbilden blir sämre om objektet är stort. Ett relativt enkelt sådant system har utvecklats på MDH [2]. System av denna typ innefattar krav på omfattande matematiska beräkningar för att få fram en bild. Idag anses den ledande utvecklingen ske av Meaney [3] som nu även tar fram ett system på Chalmers i Göteborg. System för stroke- och hjärnblödningsdetektion är under utveckling hos EMTensor i Österrike [4,5] och Medfield diagnostics i Göteborg [6]. Problemen med direkt vågutbredning med s.k. ytvågor längs skallytan blir stora eftersom man inte kan sänka ned skallen i vätska. Absorberande s.k. bolusar och även viss metallisk avskärmning (»huva») används av EM Tensor. En forskningsgrupp under Abbosh [7] har i laboratoriemiljö helt utan störningar lyckats uppnå vissa resultat utan bolusanvändning. Typiska antenner är modifierade kommunikationsantenner och man använder ett spektrum av frekvenser. Återigen blir systemen beräkningsintensiva. På MDH utvecklas f.n. två olika system. Det första har tredimensionella antenner och speciella åtgärder för eliminering av ytvågorna [8] samt kräver matematiska beräkningar som alla de föregående. Det andra bygger på en annan princip: polariserad direktdetektion av den. s.k. diffraktionen från exv. hjärnblödningsområdet och användning av vad som inte är antenner i vanlig mening [9]. Endast mycket enkel bildbehandling krävs, inte heller statistisk träning krävs för framtagning av slutdata så som tillämpas i exv. oljeindustrin för bestämning av olja/vatten/gas med mikrovågsteknik. Sammanfattningsvis karaktäriseras området av ett flertal aktiviteter, varav några pågått i många år. Orsaker till tidsutdräkterna är dels givetvis de allmänna svårigheterna med mikrovågsavbildning, men en ytterligare orsak är att mikrovågsvetenskapen och tekniken i sig är tvärvetenskaplig. En konsekvens av detta är att man inte tillräckligt tidigt ägnat sig åt de speciella ytvågs- och diffraktionsfenomen som kan förbättra mätresultaten.

  • 15.
    Risman, Per Olov
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Petrovic, Nikola
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Arch-Trapped Propagation in Enclosed and Free Space Biological Objects2018In: 2018 IEEE CAMA Conference on Antenna Measurement and Applications CAMA 2018, 2018Conference paper (Refereed)
    Abstract [en]

    The tendency of arch-trapped microwave propagation at curved surfaces is a kind of diffraction which needs more attention in the development of measurement systems, from the oil industry to the investigations using antenna applicator systems for biological objects. We develop equations for propagation in very lossy substances in metal pipes. Similar such propagation occurs at the periphery of rounded objects in air, where also surface wave effects occur and can cause measurement problems. We show a modified contacting antenna applicator minimizing arch-trapped as well as surface waves.

1 - 15 of 15
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf