A new tuning scheme for linearly tunable high-Q filters is proposed. The tuning method is based on using the phase information for both frequency and Q factor tuning. There is no need to find out the relationship between a filter's passband magnitude and Q. A gm-C biquadratic filter is designed to demonstrate the proposed tuning circuitry. The project includes a phase locked loop (PLL) based frequency tuning loop, reference clock generator, and differential difference amplifier (DDA) for dealing with frequency and Q factor tuning loop and linearly tunable second order gm-C bandpass filter. Simulation results for a 10 MHz prototype filter using AMI 0.5μm process is presented. The chip testing results show that the automatic frequency tuning error is 2.5% for the 10 MHz case.

This master’s thesis describes a way to represent vehicles when tracking them through an image sequence. Vehicles are described with a state containing their position, velocity, size, etc.. The thesis highlights the properties of homographies due to their suitability for estimation of projective transformations. The idea is to approximatively represent vehicles with planes based on feature points found on the vehicles. The purpose with this approach is to estimate the displacement of a vehicle by estimating the transformation of these planes. Thus, when avehicle is observed from behind, one plane approximates features found on the back and one plane approximates features found on the side, if the side of the vehicle is visible. The projective transformations of the planes are obtained by measuring the displacement of feature points. The approach presented in this thesis builds on the prerequisites that a camera placed on a vehicle provides an image of its field of view. It does not cover how to find vehicles in an image and thus it requires that the patch which contains the vehicle is provided. Even though this thesis covers large parts of image processing functionalities, the focus is on how to represent vehicles and how to design an appropriate filter for improving estimates of vehicle displacement. Due to noisy features points, approximation of planes, and estimated homographies, the obtained measurements are likely to be noisy. This requires a filter that can handle corrupt measurements and still use those that are not. An unscented Kalman filter, UKF, is utilized in this implementation. The UKF is an approximate solution to nonlinear filtering problems and is here used to update the vehicle’s states by using measurements obtained from homographies. The choice of the unscented Kalman filter was made because of its ease of implementation and its potentially good performance. The result is not a finished implementation for tracking of vehicles, but rather a first attempt for this approach. The result is not better than the existing approach, which might depend on one or several factors such as poorly estimated homographies, unreliable feature points and bad performance of the UKF.

Due to the release of 3.1-10.6 GHz band, UWB systems have a rapidly progressive development. They have been widely employed in short-range communication applications and large-bandwidth handheld devices. As part of the system, the UWB antenna plays an extremely important role. Due to the trend towards integrated printed circuits, co-planar waveguide technology is a feasible solution for designing the UWB antenna. This thesis focuses on designing a UWB co-planar waveguide antenna with a band-stop filter. This band-stop filter offers rejection to unwanted frequencies in the range of the operating band in order to avoid unnecessary interference from other communication applications and improve its own system’s performance. In addition, it can divide the whole wide band into a few sub-bands. This will create more flexibility for practical applications. The professional full-wave field solver software package CST Microwave Studio is used as the analysis tool to obtain the performances of this antenna. It operates from 3.1 GHz to 10.6 GHz with a VSWR < 2 in the pass bands, and a VSWR > 2 in the stop bands. The selected frequencies demonstrate nearly omni-directional characteristics in radiation patterns. Comparing with other published UWB antenna designs, relatively reasonable group delay results are achieved. Measurements on a fabricated prototype validate the design approach. / Graduate / 0537 / wang@uvic.ca

No description available.

Diss. Ronneby : Tekn. högsk., 2002.

Zugl.: Stuttgart, Universiẗat, Diss., 2007.

Zugl.: Stuttgart, Univ., Diss., 2007.

Zugl.: Hagen, Fernuniv., Diss., 2008

Stuttgart, Univ., Diss., 2000.

Zugl.: Stuttgart, Univ., Studienarb., 2004.