Sökning: "Mode Matching Technique"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden Mode Matching Technique.

1. 1. Effective vibro-acoustical modelling of rubber isolators

   Författare :Michael Coja; Leif Kari; Wolfgang Kropp; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Applied mechanics; Rubber isolator; Bush mounting; Dynamic stiffness; Waveguide; Fractional derivatives; Mode-matching; Pre-compressed; Prestrain; Preload; Predeformation; Viscoelasticity; Dispersion; Teknisk mekanik; Engineering mechanics; Teknisk mekanik;

   Sammanfattning : This thesis, gathering four papers, concerns the enhancement in understanding and modelling of the audible dynamic stiffness of vibration rubber isolators including experimental measurements. Paper A studies the performances of three different types of vibration isolator using an indirect measurement technique to estimate the blocked dynamic transfer stiffness of each specimen. LÄS MER

3. 2. Thick Frequency Selective Structures

   Författare :Björn Widenberg; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustics; Elektromagnetism; optik; akustik; optics; Electromagnetism; Energy Saving Window; Radome; Finite Elemente Method; Frequency Selective Structure; Mode Matching Technique;

   Sammanfattning : This thesis presents a new method that can handle a general thick Frequency Selective Structure (FSS), that consists of an arbitrary number of aperture layers and dielectric layers. The method is based on the Mode Matching Technique (MMT) and the finite element method (FEM). The thesis consists of a General Introduction and five scientific papers. LÄS MER

4. 3. VCSEL and Integration Techniques for Wavelength-Multiplexed Optical Interconnects

   Författare :Mehdi Jahed; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wavelength setting; optical interconnects; mode control; vertical-cavity surface-emitting laser; flip-chip integration; wavelength-division-multiplexing; silicon photonics;

   Sammanfattning : GaAs-based vertical-cavity surface-emitting lasers (VCSELs) are dominating short-reach optical interconnects (OIs) due to their high modulation speed, low power consumption, circular output beam and low fabrication cost. Such OIs provide the high bandwidth connectivity needed for interconnecting servers and switches in data centers. LÄS MER

5. 4. Two-Dimensional Signal Root Estimation in Blind Multichannel Impact Response Analysis

   Författare :Joakim Axmon; Matematisk statistik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; forestry; Silviculture; detection of decay.; Norway spruce; X-texture mode; signal subspace enhancement; partial forward-backward averaging; ESPRIT; state-space; Prony; frequency analysis; SIMO; impact response; Modal analysis; impact excitation; forestry technology; Skogsvetenskap; skogsbruk; skogsteknik; Electrical engineering; Elektroteknik; Signal processing; Signalbehandling;

   Sammanfattning : This doctoral dissertation concerns two-dimensional frequency estimation for modal analysis of single-input multiple-output impact responses from circularly cylindrical objects. The application is within detection of internal defects in trunks of spruce. LÄS MER

7. 5. Miniaturized Hard Waveguides in Multifunction Array Antennas

   Författare :Malcolm Ng Mou Kehn; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; interlaced arrays; Floquet theorem; reflector antennas; focal plane array; multifunction antennas; miniaturized waveguides; multilayer structures; spectral domain technique; periodic structures; aperture reuse; method of moments; soft and hard surfaces; array antennas;

   Sammanfattning : Recent advances in technologies of wireless communications systems have led to an increasing desire for several antennas performing diverse functions at different frequencies to be integrated into a common radiating aperture. This gives rise to the so-called multifunction antenna, which affords the saving of scarce premium real estate and can alleviate problems arising from excessive antenna protrusions in aspects such as aerodynamics, aesthetics, and stealth capability in military applications. LÄS MER