<p>Examensarbete har utförts för AIAB DC Systems i Karlstad.</p><p>Vår uppgift gick ut på att göra ett övervakningssystem för DC-system. Enheten skall användas för att övervaka isolerade DC-system avseende spänningsnivåer och isolation samt larma vid fel. Tidigare har man haft ett analogt system ute på marknaden men nu vill man ha ett digitalt processorbaserat system.</p><p>Vi har använt oss av en 8-bitars RISC-processor. Programmeringen har gjorts i assembler med hjälp av ett utvecklings-kit och sköter logiken för övervakningen. Programmet manövreras med två tryckknappar och en display.</p><p>Programmet vi har tagit fram behöver kompletteras med vissa funktioner. Vi har inte hunnit få klar en prototyp eftersom projekttiden tog slut.</p> / <p>This thesis was performed for AIAB DC Systems in Karlstad.</p><p>Our task is to make a monitoring system for DC-system. The unit is used to supervise voltage and isolation in isolated DC-systems. The unit shall alarm if there is any failure in the system. The company now has an analog solution on this product but now they want a digital version.</p><p>An 8-bit RISC processor has been used to take care of the logic. The programming has been done in assembler with the help of a developing kit. The program operates with two buttons and a display.</p><p>The program that we made needs to be added with some functions. We haven’t got a prototype ready yet due to the project time was expired.</p>

A current focus among communication engineers is to design flexible radio systems in order to handle services among different telecommunication standards. Efficient support of dynamic interactive communication systems requires flexible and cost-efficient radio systems. Thus, low-cost multimode terminals will be crucial building blocks for future generations of multimode communication systems. Here, different bandwidths, from different telecommunication standards, must be supported and, thus, there is a need for a system which can handle a number of different bandwidths. This can be done using multimode transmultiplexers (TMUXs) which make it possible for different users to share a common channel in a time-varying manner. These TMUXs allow bandwidth-on-demand so that the resulting communication system has a dynamic allocation of bandwidth to users. Each user occupies a specific portion of the channel where the location and width of this portion may vary with time. Another focus among communication engineers is to provide various wideband services accessible to everybody everywhere. Here, satellites with high-gain spot beam antennas, on-board signal processing, and switching will be a major complementary part of future digital communication systems. Satellites provide a global coverage and if a satellite is in orbit, customers only need to install a satellite terminal and subscribe to the service. Efficient utilization of the available limited frequency spectrum, by these satellites, calls for on-board signal processing to perform flexible frequency-band reallocation (FFBR). Considering these two focuses in one integrated system where the TMUXs operate on-ground and FFBR networks operate on-board, one can conclude that successful design of dynamic communication systems requires high levels of flexibility in digital signal processing structures. In other words, there is a need for flexible digital signal processing structures that can support different telecommunication scenarios and standards. This flexibility (or reconfigurability) must not impose restrictions on the hardware and, ideally, it must come at the expense of simple software modifications. In other words, the system is based on a hardware platform and its parameters can easily be modified without the need for hardware changes. This thesis aims to outline flexible TMUX and FFBR structures which can allow dynamic communication scenarios with simple software reconfigurations on the same hardware platform. In both structures, the system parameters are determined in advance. For these parameters, the required filter design problems are solved only once. Dynamic communications, with users having different time-varying bandwidths, are then supported by adjusting some multipliers of the proposed multimode TMUXs and a simple software programming in the channel switch of the FFBR network. These do not require any hardware changes and can be performed online. However, the filter design problem is solved only once and offline.

This thesis considers problems related to the design and the analysis of wide-angle scanning phased arrays. The goals of the thesis are the design and analysis of antenna elements suitable for wide-angle scanning array antennas, and the study of scan blindness effects and edge effects for this type of antennas. Wide-angle scanning arrays are useful in radar applications, and the designs considered in the thesis are intended for an airborne radar antenna.After a study of the wide-angle scanning limits of three candidate elements, the tapered-slot was chosen for the proposed application.A tapered-slot antenna element was designed by using the infinitive array approach and the resulting element is capable of scanning out to 60° from broadside in all scan planes for a bandwidth of 2.5:1 and an active reflection coefficient less than -10 dB. This design was implemented on an experimental antenna consisting of 256 elements.The predicted performance of the antenna was then verified by measuring the coupling coefficients and the embedded element patterns, and the measurements agreed well with the numerical predictions.Since the radar antenna is intended for applications where stealth is important, an absorbing layer is positioned on top of the ground plane to reduce the radar cross section for the antenna's cross-polarization.This absorbing layer attenuates guided waves that otherwise lead to scan blindness, but does not adversely affect the antenna performance for the desired scan directions and frequencies.The highest frequency limit of the tapered-slot element is set by scan blindnesses. One of these scan blindnesses is found to be unique to tapered-slot elements positioned in triangular grids. This scan blindness is studied in detail and a scan blindness condition is presented and evaluated.The evaluation of the experimental antenna shows that edge effects reduce the H-plane performance of the central elements.These edge effects are further studied and characterized, by comparing the scattering parameters for finite-by-infinite arrays and infinite arrays.In this way it is possible to divide the edge effects into two categories: those caused by finite excitation, and those caused by perturbed currents due to the geometry of the edge. A finite difference time domain code with time shift boundaries is used to compute the active reflection coefficients needed to compute the scattering parameters, but this code cannot directly compute the active reflection coefficient for all the required phase shifts.Hence, an additional method is presented that makes it possible to compute arbitrary phase shifts between the elements using any numerical code with limited scan directions. / QC 20100712

One of the demands for future wireless communication systems is higher data rates. New applications demand higher data rates and higher data rates give the service providers the possibility to offer new services. To achieve higher data rates the concept of MIMO (Multiple-Input Multiple-Output) systems has emerged. The basic principle behind MIMO is to use multiple antennas in contrast to the currently deployed systems mostly based on single antenna systems. The handheld devices need to be small and at the same time ver- satile due to the mobility of the user. To improve the overall performance following the MIMO paradigm, several antenna elements may be introduced on each handheld device. Requiring one feed chain per antenna element, this would result in a considerable increase in space, cost, and complexity and makes the implementation of large MIMO systems a difficult task. One way to overcome the setbacks is the use of reconfigurable antennas. For a fixed number of antenna elements in an antenna array, the choice of reconfigurable elements will increase the number of possibilities. The reconfigurability is preferably achieved by integrating switches with the antenna to save space. RF-MEMS (Radio Frequency Microelectromechanical Systems) switches be- long to a relatively new concept with advantages such as having low loss, better bandwidth properties, and demanding low actuation voltage. In this thesis, two different topics are treated related to wireless com- munication. Part I presents four different reconfigurable MEMS integrated antennas for MIMO applications. A frequency reconfigurable meander slot antenna, a polarization reconfigurable PIFA, and a frequency reconfigurable PIFA are presented followed by a pattern reconfigurable monopole array. Sim- ulation and measurement results are presented along with brief discussions on the topic of antenna selection with reconfigurable antenna elements. In addi- tion, channel measurements are presented for the reconfigurable array with an analysis of the impact of the reconfigurable antenna on the wireless channel. Part II presents an estimator for the coupling matrix of an antenna ar- ray with two slightly different approaches. In adaptive antenna arrays, signal processing is used as a basis for decisions. An accurate estimate of the in- coming signal is therefore of importance. As part of that, the modelling of the antenna array is crucial. Otherwise, the estimated signal could be biased and the decision made based on that will deviate from the optimal choice. Assuming ideal behavior by the antenna array when estimating the incoming signal is typically something that leads to results that deviate from the op- timum and reduces the performance. One of the major contributors to the non-ideal behavior is the mutual coupling between the antenna elements of the array. The coupling matrix is introduced and represents the interaction between the different antenna elements of an antenna array, called mutual coupling. To model a non-isotropic behavior, another matrix is introduced representing the element factor. A possible shift relative to the phase center of the array may occur because of difficulties finding the true phase center, which is also modelled with a matrix. The problem discussed in Part II of this thesis is that of finding the coupling matrix using the matrix based model. When the coupling matrix is found, a more accurate estimate of the signal is possible leading to improved performance. The introduction of the element factor and phase center representations improve the accuracy of the coupling matrix estimation, which is seen in the subsequent analysis of the estimator. CRB is derived and discussed in terms of parameter cost. / QC 20100803

In a wireless radio network system, with an evolving standard, there is a need to increase system capacity due to the increase in the traffic demands, the higher data rate usage, and the need to further extend the coverage of the system. One possible solution is to use multiple antennas (co-located or distributed) for the radio links. The aim of this thesis is to estimate the capacity gain for these advanced antenna scenarios in comparison to the ones in current use (e.g. single antenna in a 3-sector site) with special emphasis on transmit diversity and beamforming techniques. The quantification of such gain is mainly performed, evaluated and analyzed in dynamic system simulators with an accurate interference modeling. A generalized Signal to Interference Noise Ratio (SINR) estimation for a MIMO DS-CDMA system is derived, and as a by-product a closed-form solution of the orthogonality factor is obtained. Moreover the effectiveness of an antenna system is evaluated in a MIMO-test bed. Transmit diversity (TXDiv) is evaluated in WCDMA systems for flat fading (i.e. Pedestrian A (PedA)) and frequency selective channels (i.e. Typical Urban (TU)). While in flat fading channels, TXDiv schemes such as Space Time Transmit Diversity (STTD) and Closed Loop Mode 1 (CL1) offer a substantial system capacity gain, the gain is negligible in frequency selective channels. In HSDPA systems, TXDiv offers negligible gain in flat fading channels and causes a significant loss in frequency selective channels. The loss is mainly due to random spatial interference patterns (the so called Flashlight Effect), that are present in the HSDPA system. A simple scheme that mitigates this phenomena is presented. The scheme yields a 70% gain for CL1 in a PedA channel, while 10% gain is observed in the TU channel. The introduction of beamforming in WCDMA systems leads to a substantial system capacity and coverage gain. Three different implementations are evaluated and analyzed: Higher Order Sectorization (HOS), Fixed Beams (FB) with S-CPICH as a phase reference and finally FB as P-CPICH as a phase reference. Further, the impact of angular spread, the interaction and impact of radio resource management as power tuning of the common channel, scrambling code allocation technique, admission control, handovers and various antenna configurations are analyzed. The 12-sector sites yield the best system capacity gain in comparison to 3-sector sites equipped with a single antenna, slightly more than a 3-sector sites equipped with 4 FB each. In HSDPA systems, FB offers an impressive capacity gain, up to 200% for a 4 FB system. Capacity estimations with a dynamic system simulator give a clear indication about the gain of the simulated system, but the robustness of any method have to be verified through test-beds. STTD with receive diversity is implemented and tested in a real-time DSP MIMO test-bed for a single carrier frequency domain equalization system. A new pilot structure for joint Carrier Frequency Offset (CFO) and channel estimation is proposed and evaluated to address the inter-symbol interference and the severe CFO due to hardware impairments. The new pilot scheme results in significant reduction of the required overhead signalling compared to previous schemes. Instead of having antennas co-located and connected to the same radio unit (i.e. BS or UE), antennas can be distributed but having the potential to cooperate together. Furthermore, the system provides a macro-diversity gain and also relaxes the hardware complexity at the BS and/or UE. Two novel methods that provide frequency and spatial diversity are proposed. The first one called Relay Cyclic Delay Diversity (RCDD), provides frequency and spatial diversity for a multihop system while requiring a lower overhead than the methods proposed in the literature. RCDD yields a high SINR gain which translates into a substantial cell throughput gain in comparison to a single hop system. The second method called two dimensional cyclic prefix (2D-CP), introduces artificial time diversity and requires only a single transmission phase for each direction in a cooperative relaying wireless communication system. Besides not requiring an antenna specific pilots, the 2D-CP provides a substantial data rate increase. / QC 20100915

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KUL-KontrollUtrustning Luftvärn används för verifieringar på modifierade och nya luftvärnssystem. Utrustningen har varit begränsad till att kunna verifiera luftvärnssystem och denna rapport är en undersökning som ser på om det finns andra områden där man skulle kunna använda utrustningen. I rapporten beskrivs svensktluftvärn i stort för att kunna förstå hur KUL används. Rapporten går igenom KUL och dess utrustning och egenskaper sen går den igenom olika förslag på områden där KUL skulle kunna användas samt problem och behov av modifikation på KUL för det aktuella området. I rapporten ingår även en sammanfatningar på de studier som har gjorts för att kunna förstå problematik runt utrustningen som t.ex. alla olika format och kommunikationssystem.

WSP Systems i Växjö är ett konsultföretag som projekterar elanläggningar för allt från bostäder till industrier. Vår uppgift är att utifrån en kravspecifikation och arkitektritning ta fram ett ritningsunderlag för en mindre kontorsbyggnad på Ljungby lasarettsområde. Uppgiften går ut på att ta fram kanalisation-, kraft- och belysningsunderlag både med datorprogram och genom teoretiska beräkningar.

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This report describes a thesis project on 15hp. The purpose of the thesis project is to build a laser projector that reacts on sound waves and thus get a laser beam to draw visualizations of sound waves on a wall. The idea was that the design would be independent and not have to be plugged into any audio equipment. This was achieved by absorbing sound waves into a microphone. Another factor was to get a “do it yourself” -feeling of the design and therefore it was chosen to be constructed using for example, old hard-drives. The result was a relatively large and bulky designed laser projector that can draw sound waves on a wall.