Change search
Refine search result
1 - 17 of 17
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • 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. Dancila, D.
    et al.
    Augustine, R.
    Töpfer, Fritzi
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dudorov, Sergey
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Hu, X.
    Emtestam, L.
    Tenerz, L.
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Rydberg, A.
    Millimeter wave silicon micromachined waveguide probe as an aid for skin diagnosis - results of measurements on phantom material with varied water content2014In: Skin research and technology, ISSN 0909-752X, E-ISSN 1600-0846, Vol. 20, no 1, p. 116-123Article in journal (Refereed)
    Abstract [en]

    Background: More than 2 million cases of skin cancer are diagnosed annually in the United States, which makes it the most common form of cancer in that country. Early detection of cancer usually results in less extensive treatment and better outcome for the patient. Millimeter wave silicon micromachined waveguide probe is foreseen as an aid for skin diagnosis, which is currently based on visual inspection followed by biopsy, in cases where the macroscopical picture raises suspicion of malignancy. Aims: Demonstration of the discrimination potential of tissues of different water content using a novel micromachined silicon waveguide probe. Secondarily, the silicon probe miniaturization till an inspection area of 600 × 200 μm2, representing a drastic reduction by 96.3% of the probing area, in comparison with a conventional WR-10 waveguide. The high planar resolution is required for histology and early-state skin-cancer detection. Material and methods: To evaluate the probe three phantoms with different water contents, i.e. 50%, 75% and 95%, mimicking dielectric properties of human skin were characterized in the frequency range of 95-105 GHz. The complex permittivity values of the skin are obtained from the variation in frequency and amplitude of the reflection coefficient (S11), measured with a Vector Network Analyzer (VNA), by comparison with finite elements simulations of the measurement set-up, using the commercially available software, HFSS. The expected frequency variation is calculated with HFSS and is based on extrapolated complex permittivities, using one relaxation Debye model from permittivity measurements obtained using the Agilent probe. Results: Millimeter wave reflection measurements were performed using the probe in the frequency range of 95-105 GHz with three phantoms materials and air. Intermediate measurement results are in good agreement with HFSS simulations, based on the extrapolated complex permittivity. The resonance frequency lowers, from the idle situation when it is probing air, respectively by 0.7, 1.2 and 4.26 GHz when a phantom material of 50%, 75% and 95% water content is measured. Discussion: The results of the measurements in our laboratory set-up with three different phantoms indicate that the probe may be able to discriminate between normal and pathological skin tissue, improving the spatial resolution in histology and on skin measurements, due to the highly reduced area of probing. Conclusion: The probe has the potential to discriminate between normal and pathological skin tissue. Further, improved information, compared to the optical histological inspection can be obtained, i.e. the complex permittivity characterization is obtained with a high resolution, due to the highly reduced measurement area of the probe tip.

  • 2.
    Dudorov, Sergey
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Töpfer, Fritzi
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Micromachined-silicon W-band planar-lens antenna with metamaterial free-space matching2012In: Microwave Symposium Digest (MTT), 2012 IEEE MTT-S International, IEEE , 2012, p. 6259654-Conference paper (Refereed)
    Abstract [en]

    In this work, we present for the first time a miniaturized planar W-band dielectric-lens antenna which is micromachined in a 300 μm silicon wafer. The antenna edge comprises a metamaterial anti-reflection geometry in order to reduce parasitic reflections at the free-space to high-permittivity dielectric interface. Furthermore, the dielectric lens is matched to a standard WR-10 metal waveguide by an optimized tapered dielectric-wedge transition. Prototype lens-antennas were fabricated in a single-mask micromachining process. The radiation pattern for the design frequency of 100 GHz was measured to 13° half-power beam-width in E-plane, a directivity of 14 dB, 15 dB side-lobe level, 15 dB reflected power for almost the whole W-band, for a lens diameter of 10 mm and an operating frequency of 100 GHz.

  • 3.
    Frid, Henrik
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Töpfer, Fritzi
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Bhowmik, Shreyasi
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dudorov, Sergey
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Optimization of Micromachined Millimeter-Wave Planar Silicon Lens Antennas with Concentricand Shifted Matching Regions2017In: Progress In Electromagnetics Research C, ISSN 1937-8718, E-ISSN 1937-8718, Vol. 79, p. 17-29Article in journal (Refereed)
    Abstract [en]

    This paper presents a study of planar silicon lens antennas with up to three stepped-impedance matching regions. The effective permittivity of the matching regions is tailor-made byetching periodic holes in the silicon substrate. The optimal thickness and permittivity of the matchingregions were determined by numerical optimization to obtain the maximum wideband aperture efficiencyand smallest side-lobes. We introduce a new geometry for the matching regions, referred to as shiftedmatching regions. The simulation results indicate that using three shifted matching regions results intwice as large aperture efficiency as compared to using three conventional concentric matching regions.By increasing the number of matching regions from one to three, the band-averaged gain is increasedby 0.3 dB when using concentric matching regions, and by 3.7 dB when using shifted matching regions,which illustrates the advantage of the proposed shifted matching region design.

  • 4.
    Oberhammer, Joachim
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Shah, Umer
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Baghchehsaraei, Zargham
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Töpfer, Fritzi
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Sterner, Mikael
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Somjit, Nutapong
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Chekurov, Nikolai
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Monocrystalline‐Silicon Microwave MEMS2013In: Proceedings of PIERS 2013 in Stockholm, August 12-15, 2013, Cambridge, MA: The Electromagnetics Academy , 2013, p. 1933-1941Conference paper (Refereed)
    Abstract [en]

    This paper gives an overview of recent achievements in microwave micro‐electromechanical systems (microwave MEMS) at KTH Royal Institute of Technology, Stockholm, Sweden. The first topic is a micromachined W‐band phase shifter based on a micromachined dielectric block which is vertically moved by integrated MEMS actuators to achieve a tuning of the propagation constant of a micromachined transmission line. The second topic is W‐band MEMStuneable microwave high‐impedance metamaterial surfaces conceptualized for local tuning of the electromagnetic resonance properties of surface waves on a high‐impedance surface. The third topic covers 3‐dimensional micromachined coplanar transmission lines with integrated MEMS actuators which move the sidewalls of these transmission lines. Multi‐stable switches, tuneable capacitors, tuneable couplers, and tuneable filters have been implemented and characterized for 1‐40 GHz frequencies. As a forth topic, micromachined waveguide switches are presented. Finally, silicon‐micromachined near‐field and far‐field sensor and antenna interfaces are shown, including a micromachined planar lens antenna and a tapered dielectric rod measurement probe for medical applications.

  • 5.
    Töpfer, Fritzi
    KTH, School of Electrical Engineering and Computer Science (EECS), Micro and Nanosystems.
    Micromachined Microwave Sensors for Non-Invasive Skin Cancer Diagnostics2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Malignant melanoma is one of the cancers with the highest incident rates. It is also the most dangerous skin cancer type and an early diagnosis is crucial for the successful treatment of malignant melanoma patients. If it is diagnosed and treated at an early stage, the survival rate for patients is 99%, however, this is reduced to only 25% if diagnosed at a later stage. The work in this thesis combines microsystem technology, microwave engineering and biomedical engineering to develop a sensing tool for early-stage malignant melanoma diagnostics. Such a tool could not only increase the clinical accuracy of malignant melanoma diagnosis, but also reduce the time needed for examination, and lower the number of unnecessary biopsies. Furthermore, a reliable and easy-to-use tool can enable non-specialist healthcare personnel, including primary care physicians or nurses, to perform a prescreening for malignant melanoma with a high sensitivity. Consequently, a large number of patients could receive a timely examination despite the shortage of dermatologists, which exists in many healthcare systems. The dielectric properties of tumor tissue differ from healthy tissue, which is mainly accounted to a difference in the water content. This difference can be measured by a microwave-based sensing technique called microwave reflectometry. Previously reported microwave-based skin measurements largely relied on standard open-ended waveguide probes that are not suitable for early-stage skin tumor diagnosis. Thus, alternative near-field probe designs based on micromachined dielectric-rod waveguides are presented here. The thesis focuses on a broadband microwave probe that operates in the W-band (75 to 110 GHz), with a sensing depth and resolution tailored to small and shallow skin tumors, allowing a high sensitivity to early-stage malignant melanoma. Prototypes of the probe were fabricated by micromachining and characterized. For the characterization, a novel type of silicon-based heterogeneous sample with tailor-made permittivity was introduced. Furthermore, the performance of the probe was evaluated in vivo. First, through measurements on human volunteers, it was shown that the probe is sensitive to artificially induced changes of the skin hydration. Then, measurements on murine skin melanoma models were performed and small early-stage skin tumors were successfully distinguished from healthy skin. Additionally, a resonant probe for microwave skin sensing was designed and micromachined protoypes were tested on phantom materials. However, the resonant probe was found less suitable than the broadband probe for the measurements on skin. The broadband probe presented in this thesis is the first microwave nearfield probe specifically designed for early-stage malignant melanoma diagnostics and successfully evaluated in vivo.

  • 6.
    Töpfer, Fritzi
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dudorov, Sergey
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dancila, D.
    Augustine, R.
    Hu, X.
    Rydberg, A.
    Emtestam, L.
    Tenerz, L.
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Micromachined near-field millimeter-wave medical sensor for skin cancer diagnosis2013In: 2013 7th European Conference on Antennas and Propagation (EuCAP), New York: IEEE , 2013, p. 1550-1553Conference paper (Refereed)
    Abstract [en]

    This paper presents the recent achievements in a project on micromachined millimeter-wave near-field medical sensors, in particular for skin cancer diagnosis. Micromachining enables sensor probes which achieve both high sensitivity and high lateral resolution through a drastically miniaturized probe tip. Two different design strategies are investigated: a broad-band, non-resonating, tapered dielectric-rod probe, and a resonance slot sensor. For probe characterization micromachined silicon test and calibration samples with tailor-made permittivity were fabricated. Characterization of fabricated prototypes show that the tapered probe can clearly and reproducibly distinguish silicon test samples of permittivity corresponding to healthy and cancerous skin tissue at 100 GHz. For the resonance slot probe the simulated response to materials of different permittivity is shown. Furthermore, the paper presents the design of phantom materials for probe evaluation on soft-matter dielectrics.

  • 7.
    Töpfer, Fritzi
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dudorov, Sergey
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dancila, Dragos
    Augustine, Robin
    Rydberg, Anders
    Emtestam, Lennart
    Tenerz, Lars
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    High-resolution microwave skin cancer diagnostic tool based on micromachined interface2012Conference paper (Other academic)
  • 8.
    Töpfer, Fritzi
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dudorov, Sergey
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    2-Dimensional near-field millimeter-wave scanning with micromachined probe for skin cancer diagnosis2013In: Micro Electro Mechanical Systems (MEMS), 2013 IEEE 26th International Conference on, New York: IEEE , 2013, p. 1057-1060Conference paper (Refereed)
    Abstract [en]

    This paper reports for the first time on the 2-dimensional scanning performance of a micromachined millimeter-wave (100 GHz) near-field probe with a substantially reduced tip size which is designed for skin cancer diagnosis. Furthermore, it introduces a novel concept of creating inhomogeneous test samples with tailor-made and locally altered permittivity which mimick skin tissue with small anomalies and are used for characterizing the probe. A probe prototype with a tip size of 300 x 600 mu m(2) and test samples with permittivity in the range of cancerous and healthy skin tissue were fabricated by micromachining and used for evaluating the sensitivity and resolution of the probe. This paper reports for the first time on 2-dimensional scanning performance, resolution, repeatability, long-term stability, and sensitivity, which are important for qualifying such measurement probes for medical applications. The resolution of the prototype, which is important for early detection of small tumor speckles, was found to be better than 200 mu m, i.e. 1/6 of the medium-normalized wavelength. The reproducibility of the probe setup including operator uncertainty is 1.36% (1 sigma) and the long term stability of reference measurements is 0.59% (1 sigma) over 8 hours.

  • 9.
    Töpfer, Fritzi
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dudorov, Sergey
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Characterization of high-resolution millimeter-wave measurement probe for skin tissue analysis2012Conference paper (Other academic)
  • 10.
    Töpfer, Fritzi
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology (Changed name 20121201).
    Dudorov, Sergey
    KTH, School of Electrical Engineering (EES), Microsystem Technology (Changed name 20121201).
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Microsystem Technology (Changed name 20121201).
    Micromachined 100GHz near-field measurement probe for high-resolution microwave skin-cancer diagnosis2012In: IEEE MTT-S International Microwave Symposium Digest: 2012 IEEE MTT-S International Microwave Symposium, IMS 2012; Montreal, QC; Canada; 17 June 2012 through 22 June 2012, 2012, p. 6259671-Conference paper (Refereed)
    Abstract [en]

    This paper reports for the first time on a novel micromachined millimeter-wave near-field measurement probe for skin-cancer diagnosis, which is designed for high lateral resolution for resolving small skin cancer speckles as well as for vertically discriminating shallow tissue-layer anomalies. A tip size as small as 0.18 mm 2, which is 18times smaller than conventional measurement tips for the design frequency of 100 GHz, could be achieved by micromachining a silicon-core tapered dielectric-rod waveguide. This metallized dielectric probe is positioned centrally into a standard WR-10 waveguide by a micromachined holder which allows for easily exchanging the probes at high reproducibility. The dielectric-wedge transition between the waveguide and the probe is optimized for 100-105 GHz. Furthermore, this paper presents a unique concept of micromachined test samples with tailor-made permittivity ranging from L.7 to 7.1, which enables emulation of the different water content of tissue anomalies. This test method results in highly reproducible test measurements for evaluating and comparing different prototype probe designs. The paper presents successful measurement results of fabricated probes and test samples. Different single test samples as well as sample stacks with emulated tissue anomalies could clearly be distinguished.

  • 11.
    Töpfer, Fritzi
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dudorov, Sergey
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Millimeter-Wave Near-Field Probe Designed for High-Resolution Skin Cancer Diagnosis2015In: IEEE transactions on microwave theory and techniques, ISSN 0018-9480, E-ISSN 1557-9670, Vol. 63, no 6, p. 2050-2059Article in journal (Refereed)
    Abstract [en]

    This paper presents a detailed technical characterization of a micromachined millimeter-wave near-field probe developed for skin cancer diagnosis. The broadband probe is optimized for frequencies from 90 to 104 GHz and consists of a dielectric- rod waveguide, which is metallized and tapered towards the tip to achieve high resolution by concentrating the electric field in a small sample area. Several probes with different tip sizes were fabricated from high-resistivity silicon by micromachining and were successfully characterized using silicon test samples with geometry- defined tailor-made permittivity. The probes show a high responsivity for samples with permittivities in the range of healthy and cancerous skin tissue at 100 GHz (from 3.2 - j2.3 to 7.2 - j8.0, loss tangent of approximately 1.26). The sensing depth was determined by simulations and measurements from 0.3 to 0.4 mm, which is adapted for detecting early-stage skin tumors before they metastasize. The lateral resolution was determined to 0.2 mm for a tip size of 0.6 x 0.3 mm, which allows for resolving small skin tumors and inhomogeneities within a tumor.

  • 12.
    Töpfer, Fritzi
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Emtestam, L.
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dermatological verification of micromachined millimeter-wave skin-cancer probe2014In: IEEE MTT-S International Microwave Symposium Digest, 2014Conference paper (Refereed)
    Abstract [en]

    This paper presents for the first time measurement data on in-vivo dermatological experiments verifying the performance of a millimeter-wave medical probe designed for skin-cancer diagnosis. The probe consists of a micromachined silicon-core dielectric-rod waveguide, which is metallized and tapered at its tip as a compromise for high field concentration at the probe-to-skin interface, high sensitivity, high resolution, and an interaction volume depth adapted to diagnosing early-stage melanoma. The in-vivo dermatological tests on humans comprise: (1) measurement at different skin sites; (2) measurements of skin burns; (3) scanning the profile of benign skin neoplasma; (4) standardized dermatological tests with skin-irritant in 5 concentrations on 5 test persons, including monitoring of the healing process and reference measurements using a commercial transepidermal water loss instrument. All tests were successfully completed and show that millimeter-wave sensors are well capable of detecting physiologic changes of the skin and experimental skin reactions.

  • 13.
    Töpfer, Fritzi
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Emtestam, L.
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Diagnosis of malignant melanoma by micromachined near-field millimeter-wave probe2016In: International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz, IEEE, 2016Conference paper (Refereed)
    Abstract [en]

    A micromachined millimeter-wave probe, optimized for early-stage skin tumor diagnosis has been verified using a murine skin cancer model. Malignant melanoma tumors are clearly distinguishable from surrounding healthy tissue, since the difference in S11 between a malignant melanoma skin tumor and surrounding healthy tissue is 6.7 times larger than typical standard deviations of measurements on the same spot. Furthermore, the probe has an 8 times higher selectivity to a tumor growing in the skin close to the surface as compared to a subcutaneous tumor buried beneath a thick healthy tissue layer. This confirms the optimized sensitivity of the probe to the targeted upper portion of the skin, in which skin tumor growth starts in malignant melanoma patients.

  • 14.
    Töpfer, Fritzi
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Micro and Nanosystems.
    Emtestam, Lennart
    Girnita, Ada
    Oberhammer, Joachim
    In Vivo Evaluation of Microwave Probe for Early-Stage Malignant Melanoma Diagnostics: Measurements on Murine Tumor ModelManuscript (preprint) (Other academic)
  • 15.
    Töpfer, Fritzi
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Emtestam, Lennart
    Oberhammer, Joachim
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Long-Term Monitoring of Skin Recovery by Micromachined Microwave Near-Field Probe2017In: IEEE Microwave and Wireless Components Letters, ISSN 1531-1309, E-ISSN 1558-1764, Vol. 27, no 6, p. 605-607Article in journal (Refereed)
    Abstract [en]

    The water content in the epidermis correlates with different pathologic states of the skin; thus its assessment can aid the diagnosis and monitoring of conditions such as inflammation, edema, burns, and skin cancer. A micromachined microwave near-field probe, operating from 90 to 106 GHz, which, in contrast to earlier used microwave probes, has a minimized sensing area of 0.6 mm x 0.5 mm and an optimized sensing depth of 400 mu m in tissue, has been developed and technically characterized by the authors earlier. This letter reports on the long-term monitoring of sodium lauryl sulfate (SLS)-induced skin irritations with the micromachined microwave probe. Aqueous solutions with 1%, 2%, 5%, and 10% SLS were applied to the forearm of a volunteer for 24 h and microwave reflection measurements were taken before and during 11 days after the SLS application. For all SLS-treated spots the microwave absorption reached the highest levels of 4 to 7 days after SLS application and afterward converged toward baseline levels again. The observed biphasic progression of the microwave reflection signal agrees well with trends from the literature for capacitance measurements and for epidermal thickness and signal attenuation in optical coherence tomography after SLS exposure. The measurements indicate that the microwave probe is very suitable to determine changes in the water content in the epidermis and can aid in the diagnosis of pathologic conditions including skin cancer.

  • 16.
    Töpfer, Fritzi
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Oberhammer, Joachim
    KTH.
    Microwave cancer diagnosis2016In: Principles and Applications of RF/Microwave in Healthcare and Biosensing, Elsevier Inc. , 2016, p. 103-149Chapter in book (Other academic)
    Abstract [en]

    For many malignant tumors a different microwave signature as compared to the surrounding tissue has been observed. Thus microwave measurements and imaging can potentially aid the diagnosis of malignant tumors, and a multitude of techniques and systems have been developed during the past decades. Active techniques include, e.g., the evaluation of the complex permittivity of a sample by free-space quasi-optical techniques and near-field probes, as well as imaging by microwave tomography and ultra-wideband radar. Furthermore, passive microwave imaging systems and hybrid techniques have been suggested. The most advanced systems exist for breast cancer imaging, of which several have reached the stage of clinical trials. Other application areas for microwave cancer diagnosis are tumors of the skin as well as brain tumors. 

  • 17.
    Töpfer, Fritzi
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Oberhammer, Joachim
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Millimeter-Wave Tissue Diagnostics: The most promising fields for medical applications2015In: IEEE Microwave Magazine, ISSN 1527-3342, E-ISSN 1557-9581, Vol. 16, no 4, p. 97-113, article id 7072578Article in journal (Refereed)
    Abstract [en]

    At the end of the 19th century, researchers observed that biological substances have frequency-dependent electrical properties and that tissue behaves like a capacitor [1]. Consequently, in the first half of the 20th century, the permittivity of many types of cell suspensions and tissues was characterized up to frequencies of approximately 100 MHz. From the measurements, conclusions were drawn, in particular, about the electrical properties of the cell membranes, which are the main contributors to the tissue impedance at frequencies below 10 MHz [2]. In 1926, a study found a significant different permittivity for breast cancer tissue compared with healthy tissue at 20 kHz [3]. After World War II, new instrumentation enabled measurements up to 10 GHz, and a vast amount of data on the dielectric properties of different tissue types in the microwave range was published [4]-[6].

1 - 17 of 17
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • 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