Sökning: "wideband"

Visar resultat 16 - 20 av 183 avhandlingar innehållade ordet wideband.

  1. 16. Ultra-Wideband Time Domain Measurement Systems for Microwave Tomography

    Författare :Xuezhi Zeng; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Time DomainMeasurement; Ultra-Wideband; EquivalentTime Sampling; Real Time Sampling; Microwave Tomography; Measurement Error; Frequency Domain Measurement;

    Sammanfattning : As a potential imaging modality for biomedical applications, microwave tomography has attracted a lot of interests in recent years. With microwave tomography, microwave signals are transmitted into the biological tissues and the scattered fields are recorded. LÄS MER

  3. 17. Design and Analysis of Highly Linear Integrated Wideband Amplifiers

    Författare :Henrik Sjöland; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CMOS; nonlinearity cancellation; intermodulation distortion; RF amplifiers; IF amplifiers; audio amplifiers; power amplifiers; wideband amplifiers; analog integrated circuits; low voltage; amplifiers; distortion; bipolar; Electronics; Elektronik;

    Sammanfattning : This dissertation deals with techniques for designing integrated amplifiers with high linearity. Amplifiers with operating frequencies from Audio to RF have been built. An enhanced feedback configuration, capable of very low distortion, is presented. LÄS MER

  4. 18. Ultra-Wideband Wireless Channels - Estimation, Modeling and Material Characterization

    Författare :Telmo Santos; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ultra-wideband; channel modeling; channel parameter estimation; material characterization; microwave measurements;

    Sammanfattning : This licentiate thesis is focused on the characterization of ultra-wideband wireless channels. The thesis presents results on ultra-wideband communications as well as on the ultra-wideband characterization of materials. The communications related work consisted in the measurement and modeling of outdoor scenarios envisioned for infostation systems. LÄS MER

  5. 19. Baluns, Hybrids and Power Dividers for Ultra- Wideband Antennas

    Författare :Syed Hasan Raza Zaidi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Multiport feeding network; baluns; packaging; power divider; Ultra-wideband; Eleven feed; gap waveguide; ring hybrid.;

    Sammanfattning : UWB (ultra wideband), depending on the application requirement, is usually referred to 2:1 bandwidth for radio/wireless applications. Here in this thesis it is also used to denote extremely wideband antenna and components at several octave bandwidth, particularly for high frequency applications, such as the 1 – 10 GHz antenna system needed for the Square Kilometer Array (SKA) radio telescope and the 2 – 14 GHz antenna system for the VLBI2010 (Very Long Base line Interferometer) project. LÄS MER

  7. 20. Ultra Wideband Impulse Radio for Wireless Sensing and Identification

    Författare :Majid Baghaei Nejad; Li-Rong Zheng; Kari Halonen; KTH; []
    Nyckelord :Ubiquitous computing; Impulse Radio; Ultra wideband; RFID; Wireless sensor; WSN; Antenna; System-on-Package; TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : Ubiquitous computing and Internet-of-Things (IoT) implies an untapped opportunity in the realm of information and communication technology, in which a large number of micro-devices with communication and/or computing capabilities, provides connectivity for anything, by anyone at anytime and anywhere. Especially, these devices can be equipped with sensors and actuators that interact with our living environment. LÄS MER