Search for dissertations about: "active and passive Measurements"

Showing result 16 - 20 of 63 swedish dissertations containing the words active and passive Measurements.

2. 16. Microphysical Properties of Snow Crystals Using Ground-Based In-Situ Instrumentation : Hunting Snowflakes

   Author : Sandra Vázquez Martín; Thomas Kuhn; Salomon Eliasson; Sandra Yuter; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Atmosfärsvetenskap; Atmospheric science;

   Abstract : Understanding what happens to hydrometeors, such as atmospheric snow particles (ice crystals, snow crystals, and snowflakes) in clouds is crucial for improving meteorolog-ical forecast and climate models. Consequently, improved predictions of the precipitation amount reaching the ground (snowfall) require accurate knowledge of the microphysical properties of ice crystals, such as their size, cross-sectional area, shape, fall speed, and mass. READ MORE

4. 17. Characterization of MIMO Antennas and Terminals: Measurements in Reverberation Chambers

   Author : Chen Xiaoming; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; channel characterization; Reverberation chamber; measurement uncertainty.; maximum ratio combining MRC diversity gain; multiple-input multiple-output MIMO capacity;

   Abstract : The reverberation chamber (RC) has drawn attention as a multipath emulator over the past decade for both passive and active over-the-air (OTA) tests. The overview of this thesis is given in Chapter 1. READ MORE

5. 18. On Spectrum Sensing for Secondary Operation in Licensed Spectrum : Blind Sensing, Sensing Optimization and Traffic Modeling

   Author : Mohamed Hamid; Ben Slimane Slimane; Niclas Björsell; Octavia Dobre; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cognitive Radio; Spectrum Sensing; Sensing Optimization; Blind Sensing; Traffic Modelling; Energy detection; Maximumum-minimum Eigenvalue Detection; Discriminant anlysis; Informations- och kommunikationsteknik; Information and Communication Technology;

   Abstract : There has been a recent explosive growth in mobile data consumption. This, in turn, imposes many challenges for mobile services providers and regulators in many aspects. One of these primary challenges is maintaining the radio spectrum to handle the current and upcoming expansion in mobile data traffic. READ MORE

6. 19. Selected Applications of Switched Capacitor Circuits : RF N-Path Filters and ΣΔ Modulators

   Author : Fahad Qazi; Jerzy Dabrowski; Atila Alvandpour; Henrik Sjöland; Linköpings universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : Electronic circuits based on switches and capacitors have been used in various applications for several decades. The common switched capacitor (SC) circuits have made their career primarily in analog filters and data converters due to high immunity to capacitance mismatch in integrated circuit (IC) technologies. READ MORE

7. 20. EMI from Switched Converters – Simulation Methods and Reduction Techniques

   Author : Andreas Henriksson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; state space methods; EMI; semiconductor device modeling; diode reverse recovery; diode modeling; conducted emissions; Semiconductor device measurements; DC DC converters;

   Abstract : In this thesis, the conducted EMI from switched power converters has been analyzed using various existing models, own-derived models as well as measurements. The ingoing passive components in a switching converter have been modeled with respect to their high frequency behavior and the static and dynamic behavior of the active semiconductors has been analyzed. READ MORE