Search for dissertations about: "Microwave antenna"

Showing result 16 - 20 of 78 swedish dissertations containing the words Microwave antenna.

  2. 16. Microwave Gas and Multipactor Breakdown in Inhomogeneous Fields

    Author : Joel Rasch; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; corona; inhomogeneous fields; multipactor; Microwave breakdown;

    Abstract : Microwave gas and multipactor breakdown remains to be one of the limiting factors for the maximum power in microwave devices. Above a certain electric field strength, the so-called breakdown threshold, free electrons can multiply by making ionizing impacts with neutral gas molecules, or causing secondary emission upon impact with system surfaces. READ MORE

  4. 17. Ultra wideband microwave hyperthermia for brain cancer treatment

    Author : Massimiliano Zanoli; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ultra wideband; treatment planning; brain cancer; applicator design; time reversal; microwave hyperthermia;

    Abstract : Despite numerous clinical trials demonstrating that microwave hyperthermia is a powerful adjuvant modality in the treatment of cancers, there have been few instances where this method has been applied to brain tumors. The reason is a combination of anatomical and physiological factors in this site that require an extra degree of accuracy and precision in the thermal dose delivery. READ MORE

  5. 18. Submillimeter-Wave Waveguide Frontends by Silicon-on-Insulator Micromachining

    Author : Adrian Gomez-Torrent; Joachim Oberhammer; Umer Shah; Goutam Chattopadhyay; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antenna; orthomode transducer; switch; waveguide; radiofrequency; beamforming network; submillimeter-wave; terahertz; silicon micromachining; deep reactive ion etching; silicon on insulator; Electrical Engineering; Elektro- och systemteknik;

    Abstract : This thesis presents novel radiofrequency (RF) frontend components in the submillimeter-wave (sub-mmW) range implemented by silicon micromachining, or deep reactive ion etching (DRIE). DRIE is rapidly becoming a driving technology for the fabrication of waveguide components and systems when approaching the terahertz (THz) frequency range. READ MORE

  6. 19. MICROWAVE IMAGING OF BIOLOGICAL TISSUES: applied toward breast tumor detection

    Author : Tommy Gunnarsson; Ylva Bäcklund; Denny Åberg; Hans Sköld; Mikael Persson; Mälardalens högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Microwave Imaging; Breast tumor detection; Inverse problems; Mammography; Electronics; Elektronik; Elektronik;

    Abstract : Microwave imaging is an efficient diagnostic modality for non-invasively visualizing dielectric contrasts of non-metallic bodies. An increasing interest of this field has been observed during the last decades. Many application areas in biomedicine have been issued, recently the breast tumor detection application using microwave imaging. READ MORE

  7. 20. Generation, Modulation, and Detection of Signals in Microwave Photonic Systems

    Author : Andreas Wiberg; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Microwave photonics; radio over fiber; mm-wave generation; PSK; QAM; subcarrier modulation; photonic frequency multiplication; spurious free dynamic range third-order intercept point; millimeter-wave photonics; uni-travelling-carrier photodiode; millimeter-wave communication system;

    Abstract : This thesis deals with the use of photonic technology in microwave and millimeter-wave applications. The two major parts of this work have been techniques for transmission and signal generation. READ MORE