Search for dissertations about: "mode filter"

Showing result 1 - 5 of 82 swedish dissertations containing the words mode filter.

2. 1. Quasi-Single Mode VCSELs for Longer-Reach Optical Interconnects

   Author : Erik Haglund; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; quasi-single mode; oxide aperture; mode filter; vertical-cavity surface-emitting laser; high-speed modulation; mode control; spectral width;

   Abstract : The vertical-cavity surface-emitting laser (VCSEL) is the standard light source in optical interconnects connecting racks in supercomputers and datacenters hosting services such as online data sharing, storage and processing. VCSELs have numerous advantages such as low power consumption, fast direct modulation at low currents, circular output beam for efficient fiber coupling and low-cost fabrication. READ MORE

4. 2. Charge Sampling Circuits and A/D Converters - Theory and Experiments

   Author : Gang Xu; Institutionen för elektro- och informationsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pipelined A D converter; sigma-delta modulator; differential difference comparator; 2-step A D converter; FIR filter; analog filter; thermal noise; clock jitter; sub-sampling; RF sampling; current-mode sampling; Charge samling; A D converter; flexible A D converter; Electronics and Electrical technology; Elektronik och elektroteknik;

   Abstract : The analysis of general charge sampling technique is presented in this thesis. Charge sampling integrates input current instead of tracking input voltage to realize high speed and low voltage sampling. The analysis focuses on the performance of general charge sampling circuits for signal capture. READ MORE

5. 3. VCSELs for High-Speed, Long-Reach, and Wavelength-Multiplexed Optical Interconnects

   Author : Erik Haglund; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; mode filter; high-contrast grating; oxide aperture; high-speed modulation; wavelength control; spectral width; vertical-cavity surface-emitting laser; optical interconnect; quasi-single-mode;

   Abstract : The vertical-cavity surface-emitting laser (VCSEL) is the standard light source in short-reach fiber-optic links in datacenters and supercomputers. These systems use an enormous number of links, making cost and energy efficiency pressing issues. READ MORE

6. 4. Gap Waveguide for High Frequency Microwave Application- Validation of Concept, Filter Design & Packaging Aspects

   Author : Ashraf Uz Zaman; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; parallel plate stopband; PMC packaging; gap waveguide; fractional bandwidth; Quasi-TEM mode; PMC surface; narrowband filter; high Q resonators;

   Abstract : The overall goal of this thesis is to validate the low loss performance of recently evolved gap waveguide technology and to use this low loss technology for designing critical passive microwave component such as narrow band filter. Also, the exploitation of gap waveguide concept as a packaging solution for densely packed RF circuitry has been presented in this thesis. READ MORE

7. 5. Tunable Filters based on Ferroelectrics and Semiconductor Varactors

   Author : Anders Eriksson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High Temperature Superconductor HTS ; quality factor; tunable filter; phase transition; circular disc resonator; Cu BCB multilayer; KTaO3; ferroelectrics; dual mode filter; SrTiO3;

   Abstract : Experimental investigation and development of tunable microwave filters, based on single crystals of SrTiO3 (STO) and KTaO3 (KTO), form the main work of this thesis. The dielectric properties of STO and KTO crystals are evaluated experimentally for a wide temperature range, with a DC bias, using parallel-plate resonators with High Temperature Superconductor (HTS) and normal metal (Cu) electrodes. READ MORE