Sökning: "ring hybrid."

Visar resultat 1 - 5 av 25 avhandlingar innehållade orden ring hybrid..

1. 1. Novel framework materials : organically templated silicogermanates and hybrid fluorotitanates

   Författare :Liqiu Tang; Xiaodong Zou; Gunnar Svensson; Gies Hermann; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; framework materials; silicogermanates; hybrid fluorotitananates; Chemistry; Kemi;

   Sammanfattning : Two types of novel framework materials, including six organically templated silicogermanates and five hybrid fluorotitanates, have been synthesized, and their structures have been determined by single crystal X-ray diffraction. Their structures and the interactions between the organic and inorganic species are discussed in some detail. LÄS MER

3. 2. 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

4. 3. EM Design for New Ultra Wide Band Technologies: Eleven Feed Baluns, Bowtie Antennas and Gap Waveguides

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

   Sammanfattning : UWB (ultra wideband), depending on the application requirement, is usually referred to more than 500 MHz bandwidth for radio/wireless applications. Here in this thesis it is also used to denote extremely wideband antennas and components of several octaves bandwidth, particularly for high frequency applications. LÄS MER

5. 4. Investigation of New Concepts and Solutions for Silicon Nanophotonics

   Författare :Zhechao Wang; Lech Wosinski; Kresten Yvind; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Planar integrated circuit; silicon photonics; slot waveguide; finite-difference time-domain; waveguide grating coupler; ring resonator; polarization diversity scheme; polarization beam splitter; polarization rotator; hybrid silicon laser; epitaxial lateral overgrowth; chemical-mechanical polishing.; Optics; Optik;

   Sammanfattning : Nowadays, silicon photonics is a widely studied research topic. Its high-index-contrast and compatibility with the complementary metal-oxide-semiconductor technology make it a promising platform for low cost high density integration. LÄS MER

7. 5. Moment Method Analysis of Antennas on Cylindrical Structures by Using G2DMULT and Design of Hat Fed Reflector Antennas

   Författare :Jian Yang; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; G2DMULT; reflector antenna; paraboloid; dipole; base station antenna; screw heads; vertex plate; self impedance; G1DMULT; ring-shaped phase center; radiation efficiency; FDTD; cylindrical structures; V2D; ring-focus; moment method;

   Sammanfattning : This thesis deals with two aspects of research interest: moment method analysis of antennas on cylindrical structures by using G2DMULT, and design of hat fed reflector antennas. Both of them are two-dimensional (2D) structure problems, one being cylindrical and the other rotationally symmetric. LÄS MER