The final goal of this document is the construction of multi-band terminal for the CVIS project to allow the communication among cars and between the cars and the roadside infrastructure. For the construction of this multi-band terminal, this document takes as starting point, a new compact disk antenna described in [1]. It consists in a circular patch antenna shorted by a central metallic post. This allows reducing the dimensions of a classical circular patch antenna so it is very useful for our application given that the terminal is going to be place on the top of a car and it should be small enough to be attractive for the final users. Specifically, we are going to analyze the behaviour of this kind of antenna when it radiates in the TM01 mode, because the radiation pattern of this mode is particularly interesting for the applications of the CVIS project. This document is divided into two main parts. In the first one, a study in depth of the behaviour of the antenna proposed in [1] was performed. Firstly, through an analytical model and afterward with the help of two simulation tools (WIPL-D and EMDS), we analyze the influence of the main parameters of the antenna (outer and inner radiuses, height, electrical permittivity and the position of the feed) on its properties (resonant frequency, bandwidth, entrance impedance, the shape of the radiation pattern and so on). A general methodology for the design of this kind of antennas was proposed, and it was put in practice with the design of a prototype for a band around 2 GHz. In addition to the conclusions about the influence of the different parameters of the antenna, another important conclusion was done. It was discovered that the use of the simulation tool WIPL-D Lite was not suitable for the simulation of this kind of antenna. In the second part, this document tackles the construction of a dual-frequency antenna for the bands of 2.4-2.484 GHz and 5.75-5.95 GHz. For this, the present document studies the possibility of stacking two compact circular patch antennas, so we put the one which covers the higher band (the smaller) on the top of the one which covers the lower band (the lager). The two patch antennas have a coaxial feed and the feed of the upper antenna goes inside the central post of the lower antenna to minimize the influence of it on the radiation pattern of the lower antenna. This proposal works out not to be feasible, because we need a lower antenna with a large inner radius to allow the variation of the feed position of the upper antenna in a wide range. This is necessary to get a good matching for the upper antenna. The problem is that the radiation pattern becomes very asymmetric when we increase the inner radius of the patch antenna. To solve that, two alternative were analyzed in this document. The first consists in putting a second feed symmetrically placed with respect to the central post. It leads to a more symmetric radiation pattern so we can choose a larger inner radius. In addition, the introduction of the second feed increases the bandwidth of the antenna. The second alternative is a simplification of the first one. It consists in replacing the upper antenna with a monopole on the top of the lower antenna. It is simpler but it prevents the possibility of stacking other patch antennas to cover more frequency bands in a future. Due to this disadvantage, the first alternative was chosen. Finally, a proposal based on the first alternative, which fulfils quite well all the requirements which were raised in the wording of this master thesis, was presented and studied in depth.

The rules of quantum mechanics makes it possible to exchange a secret key at a distance. This is called quantum key distribution (QKD). In theory the key exchange can be made completely secure. Real QKD implementations however, has numerous imperfections. Luckily one has also been able to prove the security of QKD with a large variety of imperfections. The field of QKD has matured over the recent years, and it has now reached commercial applications with photons as the quantum bits, and optical fibers as the quantum channel. Today there are at least three commercial vendors of QKD-systems. We live in the times of quantum hacking. Researchers has begun the task of breaking the security of QKD-systems. Many new imperfections has been discovered, some of which might be used to break the security of QKD. This thesis is a study of the detector efficiency mismatch loophole. Most QKD-systems require two detectors, and it is virtually impossible to make two identical detectors with the exact same efficiency. What is worse, it turns out that the eavesdropper can often control the relative efficiencies of the two detectors trough some domain, for instance by controlling the timing, the frequency or the spacial mode of the photons. This can in turn be used by the eavesdropper to gain information about the secret key. Previously the best known attack would compromise security if the detector efficiency mismatch of about 1:15. Here the current attacks on systems with detector efficiency mismatch are improved to compromise security for a mismatch of about 1:4. This is less than the mismatch found in a commercial QKD-system, so the attack could in principle be used to eavesdrop on this QKD-system. One might try to close the loophole by modifying the implementation. One suggestion is the four state Bob. The problem is that this patch will in turn open other loopholes, and one of these loopholes reopen the detector efficiency mismatch loophole. One can remove Eves information about the key by doing a sufficient amount of extra privacy amplification. Here a general security bound is presented, quantifying the required amount of extra privacy amplification to remove Eve's information about the key. The proof is more general than the previous security proof, and is valid for any basis dependent, possibly lossy, linear optical imperfections in the channel and receiver/detectors. Since this is more realistic assumptions for a QKD-implementation, the proof represents a major step of closing the loophole in real devices.

In the last two decades, magnetic resonance spectroscopy (MRS) has had an increasing success in biomedical research. This technique has the faculty of discerning several metabolites in human tissue non-invasively and thus offers a multitude of medical applications. In clinical routine, quantification plays a key role in the evaluation of the different chemical elements. The quantification of metabolites characterizing specific pathologies helps physicians establish the patient's diagnosis. Estimating quantities of metabolites remains a major challenge in MRS. This thesis presents the implementation of a promising quantification algorithm called selective-frequency singular value decomposition (SELF-SVD). Numerous tests on simulated MRS data have been carried out to bring an insight on the complex dependencies between the various components of the data. Based on the test results, suggestions have been made on how best to set the SELF-SVD parameters depending on the nature of the data. The algorithm has also been tested for the first time with in-vivo 1H MRS data, in which SELF-SVD quantification results allow the localization of a brain tumor.

This thesis is based on work done at the Norwegian University of Science and Technology (NTNU) in the field of serious gaming. The motivation for the work is to create a serious game with the purpose of recruiting high school students that undertake studies at NTNU within engineering and science. After considerations of several available tools, Blender was chosen as the best development tool for this kind of game, and used to create "Student Quest - A First Person Student Game". The game analysis shows that the game's Primary Learning Principle is Marketing, the Primary Educational Content is Knowledge Gain through Exploration, the Target Age Group is Middle and High School, and it is developed for a Computer Platform. By extracting the fun factors, we conclude that the game passes the Playability threshold and reaches the Enjoyability threshold. By implementing the potential features suggested, the game may reach the Super Fun threshold and thus has the potential of becoming an extremely entertaining serious game.

This report will describe the simulation of a Wilkinson Power Divider, realised using lumped components to minimize its size. Every step in the process, from calculating the lumped component values to the final momentum s-parameter simulation is discussed. All relevant theory is described in the theory section. The main goal of this project is to produce the Wilkinson Power Divider using TriQuints 0.5 um TQPED process in as small area as possible. The response of the circuit should also be made as close as possible to the ideal Wilkinson Power Divider. An important additional goal is to learn to use a relevant high-frequency design tool (Agilent ADS) and to get a good understanding of MMIC technology, including the components used and various effects such as cross-talk. During the project a practical measurement on components produced using the TriQuint process will be done, which gives a good understanding of practical measurements using probe station and network analyzer. The final layout, that is arrived at in three steps from a regular Wilkinson Power Divider, should be ready for production, and shows good performance while occupying only a 403 um * 271 um area. The design is thoroughly simulated using Momentum simulation and compared to the ideal response. Any discrepancy between the two responses is explained and commented. All the measurements is compared to simulation results, and deviations between the two is pointed out, and the most probable causes of these are described.

Today Lithium Ion batteries are extensively used in all kinds of electronic equipment due to its superior properties. However, Lithium Ion batteries need to have all the individual cells monitored to ensure the safety and long life time. This master thesis' objective is to design a managing system for a ten cell Lithium Ion battery with an Atmel AVR microcontroller. The main challenge was to scale down the high voltage level a 10 cell battery has and still maintain accuracy when reading this voltage with the AVR. This was solved by using current sense monitors which can handle large common mode voltages. Hardware was made to show proof of concept. It was found that the scaling circuitry had an accuracy of 46mV. In competition with other single chip devices, some other methods have to be found. The design in this thesis is physically too large and too expensive to be of any commercial use. However some other methods worth looking into have been proposed in the last chapter.

Challenged by the LTE system, Mobile WiMAX is set to be the next generation broadband wireless system. Providing high data rates over large distances gives unlimited possibilities for services provided to the end users. As for all undeveloped systems, Mobile WiMAX has also been exposed to rumors and hypes. This thesis is based on the work performed in cite{prosjekt}, and aims to provide radio planning of a Mobile WiMAX network in the populated areas of Trondheim, Norway. Moreover, preparatory work and suggestions for field testing of the deployed system have been provided. The coverage prediction have been performed by using Astrix 5.0, the radio planning tool of Teleplan. A total of 32 base stations have been suggested to provide ubiquitous coverage of -94 dBm using 92 sectors within the $35.63 km^2$ large area. Furthermore, it has been recommended that fixed or nomadic users purchases the si-CPE or CPE PRO for better channel quality and throughput performances at indoor locations. In the preparatory phase prior to field testing, a python script has been created to perform automated performance testing. The reason for automating the performance measurements has been to increase the test efficiency, and to reduce the possibility of human errors in parameter setting, and file naming. This thesis will hopefully serve as a guide for future radio planners, where an Astrix user case, measurement scripts, and data processing codes are provided for revision and editing. The work has been performed on the initiative of Wireless Trondheim.

GaAs/AlGaAs core-shell nanowires (NWs) were grown on GaAs(111)B substrates by Au-assisted molecular beam epitaxy (MBE) to investigate how different Al compositions in the shell influences the structural and optical properties of the NWs. Investigations with a secondary electron microscope (SEM) revealed that an increase in Al content leads to an increase in radial growth rate and a decrease in the axial growth rate of the AlGaAs shell. Low temperature μ-photoluminescence (PL) measurements showed that there was great improvement in the luminescence for the GaAs/AlGaAs core-shell NWs compared to GaAs NWs without shell.

This master's thesis describe electromagnetic simulations of a gallium antimonide (GaSb) light emitting diode, LED. A problem for such devices is that most of the generated light is reflected from the surface due to total internal reflection, and is therefore prevented from coupling out of the semiconductor material. Etching out a 2D photonic crystal grating on the LED surface would put aside the absolute rule of total internal reflection, and could therefore be used to increase the total transmission. The simulation method which was developed was supposed to find geometry parameters for the photonic crystal to optimize the light extraction. A set of plane waves were therefore simulated using FDTD to build an equivalent to the Fresnel equations for the photonic crystal surface. From that the total transmittance and radiation patterns for the simulated geometries were calculated. The results indicated an increase in the transmission properties of up to 70% using a square grating of holes where the holes have a radius of 0.5µm, the hole depth is 0.4µm, and the grating constant is 1µm. A hexagonal grating of holes and a square grating of isotropically etched holes were also simulated, and featured improvements on the same scale, but with different dimensions for the holes. The simulations were computationally very demanding, and the simulation structure therefore had to be highly trimmed to limit the calculation time to reasonable values. This might have reduced the accuracy of the results. Especially the optimum grating constant, and the value of the optimum improvement itself is believed to be somewhat inaccurate.

Sun exposure and climate therapy is an effective treatment for psoriasis. However, even though this treatment gives the patients relief from their discomforting symptoms, it has some potentially dangerous side effects such as an increased risk of skin cancer and premature skin aging. A prospective field study plans to follow the patients undergoing the climate therapy. During this study the UV dose to each patient will be monitored by personal dosimeters worn by the patients. Furthermore the patients' skin spectra acquired by the means of optical spectroscopy will be obtained daily. Both psoriatic skin a unaffected skin will be observed. These data will be used to assess the skin changes which take place during the psoriasis treatment. This project is focused on developing an automatic algorithm for handling bulk spectrometric measurements data and to propose ways of numerically evaluating the skin spectra. These numerical values will be later used to compare the daily patients' spectra and monitor progress of the treatment. An inverse model based on a lookup table and successive iteration was proposed in this project. The model matches the diffuse skin reflectance spectra modeled with a diffuse skin model with the measured patients skin spectra. The measured skin spectra are then defined by the diffuse skin model input parameters which were found by the inverse model. These parameters are oxygenation, blood volume and melanin absorption coefficient. Additionally four indexes were proposed to supplement the parameters found by the inverse model, namely the erythema index, melanin index, hemoglobin index and oxygenation index. Measurements of several skin spectra including psoriatic plaques spectra were carried out and used to test the inverse fitting model performance. The proposed model proved to match the measured spectra in an acceptable form employable for distinguishing between different measured spectra. The highest deviation is at the ends of the spectra due to the use of a constant value of scattering coefficient and additional parameters not directly relevant to sun exposure, hence not considered by the model. The proposed parameters together with the indexes proved to be a viable means of evaluating the healing in the psoriatic plaques as well as determining the changes caused by the sun in normal skin.