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  • 1.
    Ching, Hsu
    Linköping University, Department of Electrical Engineering.
    Techniques for High-Speed Digital Delta-Sigma Modulators2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this theses techniques for high-speed digital delta-sigma modulator(DDSM) structures are considered. Four techniques are applied andevaluated: unfolding, increasing the number of delay elements in theinner loop, pipelining/retiming, and optimizations provided by thesynthesis tool. Of interest is to see the speed-area-power trade-offs.For implementation, three different modulators meeting the samerequirements are implemented. Each modulator has a 16-bit input andresults in a 3-bit output. The baseline case is a second-ordermodulator, which has one delay element in its inner loop. Throughoptimization, two new structures are found: to provide two delayelements in the inner loop, a fourth-order modulator is required,while to provide three delay elements, a thirteenth-order modulator isobtained.The results show that in general it is better to unfold the modulatorthan to obtain the speed-up through optimizing the arithmeticoperators with the synthesis tool. Using correct pipelining/retimingis also crucial. Finally, for very high-speed implementation, usingthe structures with more delay elements is required. Also, in manycases these are more area and power efficient compared to usingoptimized arithmetic operators, despite their higher computationalcomplexity.

  • 2.
    Kantzon, David
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    PFC-design for frequency converter2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis deals with power factor correction for three-phase systems. A boost-buck topology was described, modeled and then simulated in MATLAB/Simulink. The simulation results show that the system provides a power factor over 99% over the tested power output range. Moreover, the harmonic injection concept was introduced which reduces the total harmonic distortion to 8.72% at full output power. A prototype system was also built using an FPGA for the control system. The prototype did not provide the performance seen in simulation but showed that the method is valid and does provide a higher power factor when used.

  • 3.
    Hammarström, Emil
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Network optimisation and topology control of Free Space Optics2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In communication networks today, the amount of users and traffic is constantly increasing. This results in the need for upgrading the networks to handle the demand. Free space optics is a technique which is relatively cheap with high capacity compared to most systems today. On the other hand, FSO have some disadvantages with the effects on the system by, for instance, turbulence and weather. The aim of the project is to investigate the use of network optimization for designing an optimal network in terms of capacity and cost. Routing optimization is also covered in terms of singlepath and multipath routing. To mitigate the problem with turbulence affecting the system network survivability is implemented with both proactive and reactive solutions.

    The method used is to implement the system in Matlab, the system should also be tested so that it works as intended. The report covers related work as well as theory behind FSO and the chosen optimization algorithms.

    The system uses modified Bellman-Ford optimization as well as Kruskal’s minimum spanning tree. K-link-connectivity is also implemented for the network survivability and multipath algorithm.

    Results of the implementation shows that the network survivability improves the robustness of the system by changing paths for traffic which is affected by broken links. Routing done by multipath will increase the throughput and also reduce the delay for the traffic.

  • 4.
    Nedstrand, Paul
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering.
    Lindgren, Razmus
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering.
    Test Data Post-Processing and Analysis of Link Adaptation2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Analysing the performance of cell phones and other wireless connected devices to mobile networks are key when validating if the standard of the system is achieved. This justies having testing tools that can produce a good overview of the data between base stations and cell phones to see the performance of the cell phone. This master thesis involves developing a tool that produces graphs with statistics from the trac data in the communication link between a connected mobile device and a base station. The statistics will be the correlation between two parameters in the trac data in the channel (e.g. throughput over the channel condition). The tool is oriented on analysis of link adaptation and by the produced graphs the testing personnel at Ericsson will be able to analyse the performance of one or several mobile equipments. We performed our own analysis on link adaptation using the tool to show that this type of analysis is possible with this tool. To show that the tool is useful for Ericsson we let test personnel answer a survey on the usability and user friendliness of it.

  • 5.
    Andersson, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Modelling of Cranking Behaviour in Heavy Duty Truck Engines2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In modern heavy duty trucks the battery is a central component. Its traditional role as an energy source for engine cranking has been extended to include powering a number of elec- trical components on the truck, both during driving and during standstill. As a consequence of this it is important to know how much a battery in use has aged and lost in terms of ca- pacity and power output. The difficulty in measuring these factors on a battery in use causes problem, since heavy duty truck batteries are often replaced too early or too late, leading to unnecessary high replacement costs or truck standstill respectively.

    The overall goal of the effort, of which this thesis is a part, is to use a model of the cranking behaviour of a heavy duty truck engine, which depends on the battery condition, to estimate the ageing and wear of a heavy duty truck battery. This thesis proposes a modelling approach to model the components involved in engine cranking.

    In the thesis work, system identification is made of the systems forming part of the cranking of a heavy duty truck engine. These components are the starter battery, the starter motor and its electrical circuit and the internal combustion engine. Measurement data has been provided by Scania AB for the evaluation of the models. The data has been collected from crankings of a heavy duty diesel engine at different temperatures and battery charge levels. For every cranking lapse the battery voltage and current have been measured as well as the engine rotational speed.

    A starter battery model is developed and evaluated. The resulting battery model is then incorporated into two different engine cranking models, Model 1 and Model 2, including a starter motor model and an internal combustion engine model apart form the battery model. The two cranking models differ in several aspects and their differences and resulting evalu- ations are discussed.

    The battery model is concluded to be sufficiently accurate during model verification, however the two cranking models are not. Model 2 is verified as more correct in in its output than Model 1, but neither is sufficiently accurate for their purpose. The conclusion is drawn that the modelling approach is sound but development of Model 2 is needed before the model can be used in model-based condition estimation. 

  • 6.
    Johansson, Robin
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Easier Encoder Installation with Signal Modulation2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Överlagrad kommunikation är förmågan att kommunicera genom en elektrisk ledare vilken samtidigt fyller en annan funktion. För att upprätthålla kommunikationen krävs att en slags signalmodulering införs som kan slå samman information i ena änden av ledaren och urskilja samma information i den andra änden. I följande rapport kommer överlagrad kommunikation studeras för en matningsledare bestående av en DC-spänning, matningen spänningsätter en pulsgivare genom en kabel innehållande flera andra ledare. Mätningar har utförts på nuvarande system, både hur en typisk pulsgivare fungerar och hur dess installationskabel kan tänkas ha betydelse för slutresultatet. I en förstudie presenteras relevanta lösningsförslag på hur kommunikationen kan upprätthållas genom matningsledaren, förslagen med störst potential tas vidare genom att simuleringar och mätningar utförs. För att hitta de relevanta lösningarna undersöks grundläggande pulsgivarinformation tillsammans med en studie på den nuvarande marknaden. Till sist presenteras fördelar och nackdelar mellan tre olika kommunikationsexempel och tillsammans jämförs de med lösningen att dra en extra kabel vid installationen, framförallt är det prisskillnaden och platsen kretsarna tar som är av intresse. Eftersom beräkningskraftiga FPGA-kretsar var en tillgång som kunde utnyttjas skapades grunden till kommunikationen där, ingen programmering av dem beskrivs dock i rapporten. Slutgiltig lösning inkluderar kopplingen mellan en FPGA och installationskabeln. Resultatet är en robust och tillsynes säker FSK-kommunikation som har verifierats i simuleringar och fysiska uppkopplingar. Godtycklig data kan skapas i FPGA-kretsarna, skickas som halv-duplex och läsas i andra änden kabeln.

  • 7.
    Gunhardson, Erica
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Indoor Positioning Using Angle of Departure Information2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    I detta examensarbete undersöks möjligheten att kunna använda en positioneringsmetod som inte enbart förlitar sig på den uppmätta signalstyrkan. Istället används en metod som bestämmer från vilken vinkel en signal uppkommer ifrån. Den här tekniken kallas för direction-finding. När informationen om signalens vinkel fastställts används den i ett positioningsfilter som uppskattar positionen. Två tillvägagångssätt har använts i den här rapporten, ett där enbart vinkeln används och ett där både signalstyrka och vinkel används.

  • 8.
    Bergström, Joakim
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Nilsson-Sundén, Hampus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Cost effective optimization of system safety and reliability2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A method able to analyze and optimize subsystems could be useful to reduce project cost, increase subsystem reliability, improve overall aircraft safety and reduce subsystem weight. The earlier the optimization of development of an aircraft in the design phase can be performed, the better the yield of the optimization becomes. This master thesis was formed in order to construct an automatic analysis method, implementing a Matlab script, evaluating devices forming aircraft subsystems using a Genetic Algorithm. In addition to aircraft subsystems, the method constructed in the work is compatible with systems of various industries with minor modifications of the script.

  • 9.
    Joelsson, Andreas
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Ohlsson, Jonathan
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Indoor propagation modelling at microwave frequencies in a server environment2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Link¨oping site is the first of Ericsson’s three information and communication technology centres. This facility will house the company’s complete portfolio and use the latest cloud technology in order to enable the research and development engineers to more efficiently test and develop new technologies. In the test lab environment there is a high capacity microwave telecommunication system called MINI-LINK. These systems operate at much higher frequencies than more traditional telecommunication systems. In the test lab these systems are communicating with a cable interface instead of its intended air interface. The purpose of this thesis is to evaluate the potential leakage of this system in the test lab environment.

    The evaluation of the leakage in the test lab is done by developing an empirical path loss model for the desired frequencies used by the equipment in the test lab. This model is later implemented in a leakage simulation tool designed in Matlab, which simulates and displays the leakage power in a 2D plane. This report mainly focuses on the process of determining the constants and the implementation of the path loss model.

  • 10.
    Bandla, Atchaiah
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Highly Linear 2.45 GHz Low-Noise Amplifier Design2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    One critical component of the communication receiver of front-end system is the low-noise amplifier (LNA). For good sensitivity and dynamic range, the LNA should provide a low noise figure and maximum attainable power gain. Another concern is the linearity of the LNA. Strong signals produce intermodulation products in a frequency band close to the operating frequency that might affect the performance of the receiver. In many cases, the intermodulation products can be reduced by increasing the current through the active device. Hence, a trade-off between power consumption and linearity must be considered when designing the LNA. The thesis includes the bias network design, stability analysis, matching network design and layout design of the LNA RF module with layout simulation. The simulation has been performed using Advanced Design System (ADS) simulation software. After implementation of LNA on a PCB, the LNA is measured with the help of the power supply unit and vector network analyzer. The proposed design aim is to provide a low noise figure (NF) and high gain while maintaining the low power consumption.

  • 11.
    Jaxne, Kristofer
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Control system for automated industry applied with LEGO Mindstorms2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Syftet med denna rapport är att redovisa ett examensarbete på kandidatnivå inom elektronik. Arbetet har syftat till att skapa en modell av en automatiserad industri i en liten skala. Modellen skulle vara enkel att använda för att visualisera hur automatisering fungerar i praktiken och hur ett styrsystem byggs. För att få ett bra genomförande och en verklighetstrogen modell studerades exempel från industrin och metoder för att optimera. Eftersom enkelhet var viktigt byggdes styrsystemet från grunden för att få full kontroll över systemet. En modell byggdes med LEGO® Mindstorms® som mekanisk grund och två robotar programmerades i C# att hantera ett orderflöde. Orderflödet styrdes från ett webbaserat användargränssnitt och kommunikationen hanterades genom en databas.

  • 12.
    Häger, Emil
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Performance Evaluation of Medium-Power Voltage Inverters2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Power inverters, used to convert DC power to AC, are often used in e.g. solar power applications. However, they tend to be impractically large and expensive; as such, power miniaturization is an active research area. In this thesis, several classes of modern power inverters are evaluated and compared with regards to size, efficiency and output quality in order to identify areas of potential improvement. Methods for estimation of THD, power losses and input ripple are created and verified against a simulation of a five-level neutral-point-clamped inverter with SPWM control. Finally, this design is implemented physically and is found to achieve 94.5% efficiency and 7% THD under low voltage laboratory conditions, while remaining smaller than an average textbook.

  • 13.
    Ericsson, Marcus
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Transmission, Storage, and Visualization of Data with ANT+2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Ultra low-powers wireless technology sensors uses when devices is used to consumeslow power. ANT+ sensors can run for years on a single coin battery. In thethesis the ANT+ sensor data is used in an application that can store and visualizethe data.

  • 14.
    Duong, Le
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    A model to predict the coverage of VHF transmissions2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    VHF står för "Very High Frequency" och är ett frekvensband som ligger i området 30 - 300 MHz. Maritim VHF är standard för Sjöfartsverket och fungerar över hela världen. Det är ett kommunikationssystem som bidrar till ökad säkerhet och kan rädda liv på sjön. Andra vanliga kommunikationssystem som mobiltelefoni fungerar inte tillförlitligt. Idag fungerar mobiltelefoni i stora delar av skärgården och längs kusterna men när det gäller kommunikation mellan fartyg längre ut till havs är den maritima VHF-kommunikationen överlägsen. Sjöfartsverket driver för sitt eget och kunders behov ett mobilradionätverk kallat kustradionätverket. Radiotrafiken i nätet sker både på Very High Frequency (VHF) och Medium frequency (MF). VHF-systemet är ett internationellt system som bland annat används till att kommunicera till sjöss och den trafiken befinner sig i frekvensbandet 155.5 - 162.025 MHz. Inom VHF-bandet finns det 55 kanaler. Kanalerna vid kustradiostationen kallas för duplexkanaler och innebär att kustradiostationerna sänder och tar emot signaler på två olika frekvenser. Radioutbredningen hos antennen som är installerad på basstationen har riktverkan i vissa riktningar och dämpningar i andra. Detta kan ses i strålningsdiagrammet under kapitlet "Täckningsmodell" och avsnittet antennen. Andra faktorer som kan påverka radioutbredningen är förluster i basstationenssystemet, topologin hos området mellan sändare och mottagare samt väderberoende utbredningsegenskaper. Genom att hitta de tänkbara faktorer som påverkar signalutbredningen kan en täckningsmodell förutses. Det är förluster som finns i basstationen, radiolänken samt förluster vid mottagarantennen.

  • 15.
    Haider, Daniyal
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    On-Chip Phase Measurement Design Study in 65nm CMOS Technology2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Jitter is generally defined as a time deviation of the clock waveform from its desired position. The deviation which occurs can be on the leading or lagging side and it can be bounded (deterministic) or unbounded (random). Jitter is a critical specification in the digital system design. There are various techniques to measure the jitter. The straightforward approach is based on spectrum analyzer or oscilloscope measurements. In this thesis an on-chip jitter measurement technique is investigated and the respective circuit is designed using 65 nm CMOS technology. The work presents the high level model and transistor level model, both implemented using Cadence software. Based on the Vernier concept the circuit is composed of an edge detector, two oscillators, and a phase detector followed by a binary counter, which provides the measurement result. The designed circuit attains resolution of 10ps and can operate in the range of 100 - 500 MHz Compared to other measurement techniques this design features low power consumption and low chip area overhead that is essential for built-in self-test (BIST) applications.

  • 16.
    Hansson, Niclas
    et al.
    Linköping University, Department of Computer and Information Science.
    Lantz, Alexander
    Linköping University, Department of Computer and Information Science.
    Fischerström, Ludvig
    Linköping University, Department of Computer and Information Science.
    A Security Analysis of Wireless Smart Home Technologies2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of electronics connected to local networks and the Internet is growingall the time. Nowadays you can control your electronics in your house even when away from home, which opens up for potential security threats. The purpose of this report is to point out the potential risks with connecting home electronics to the Internet and to shed light on what security mechanisms that are needed in these kinds of systems. This report contains a theoretical part in which relevant material has been summarized. This material includes the smart home solution Tellstick Net and the wireless technologies ZigBee and Z-Wave, which are commonly used in home automation. The Tellstick Net system was mapped out and a risk analysis with attack trees was performed. After the analysis of the system, the implementation of two potential security threats were attempted. The two attempted attacks were replay attack and cross-site request forgery. The replay attack was unsuccessful due to the way the system communicates and keeps connections alive. However, the cross-site request forgery was discovered to be successful in some cases. It depended on if the browser of the target supported cross-origin resource sharing, as that property protects against cross-site request forgery. Finally, the report discusses what impact the found security deficiencies have, what they entail and how they reflect on the need for security in smart technologies for the home.

  • 17.
    Khan, Muhammad Awais
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    A Study on the Aliasing-image Problem in I/Q Modulators Employing RF-DACs2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In today’s world of high-speed communication, data-converters are playing a vital role. The purpose of this project is to analyze the aliasing image problem that occurs in quadrature I/Q modulators utilizing radio frequency digital-to-analog converters (RF-DACs). The RF-DAC is considered to be high-speed DAC that operates in higher GHz region. These high performance DACs are becoming the most essential part of the upcoming future communication devices like next generation radars and telecommunication systems. Some I/Q modulators are implemented in this thesis. The aim is to identify the unwanted signal that is trying to distort the desired output.

    In this thesis, the work is divided into two main parts. First is the aliasing image verification and second is the implementation of the I/Q modulators. Begin with the assessment of the aliasing image through sketching the spectrum using Matlab tools. Also mathematically the calculation is derived to support the flow. In the next part, four different architectures are implemented focusing on image rejection ratio (IRR) calculation while the maximum achievable rejection ratio is 119 dB using the RF-DAC. Lastly the effect of discrete local oscillation (LO) is shown. A comparison plot is drawn, comparing the effect of a discrete-LO at different bit levels vs. IRR variation. It shows a nice picture of IRR dependence on the perfect matching and not on the signal shaping. 

  • 18.
    Carlsson, Jacob
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Isolated WiFi Environments2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    WiFi is becoming common in households and digital devices needs to support it. At the same time the devices are getting smaller and the Ethernet port may seem superfluous. When testing these devices the test environment needs to be able to provide WiFi connectivity. The tests may be focused on testing WiFi but it could also be the only network connectivity and thus needs to be very reliable. With a large number of devices in a small physical area a normal WiFi setup would have a density of devices that is too high for today’s1 WiFi standards. A combination of wired physical medium and physical isolation was considered.

  • 19.
    Prasad Rao Pasupuleti, Krishna
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Investigation and Study of Crosstalk2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Crosstalk is defined as an unwanted coupling between the conductors. By this it is meant that signals from one of the signal conductors (a generator in this case) are coupled to another signal conductor (receptor), or conductors (receptors), depending on the number of conductors in the vicinity of the generator. Crosstalk in this way affects the signal level on the receptor and thereby affects the total system performance within the system. This can happen in several ways, one of which is through edge coupling. Edge coupling is a process where two signal conductors are placed beside each other in the same layer while the ground conductor could have been placed either under these conductors, in a separate layer like Mclin (Microstrip coupled lines) and Sclin (Coupled striplines), or beside the signal conductors as in Cpwcpl2 (Coplanar wave guide coupled lines). This then means that edge coupling occurs through the sides where the generator and the receptor are facing each other. Broadside coupling is another way, where it occurs when the signal conductors are broadside faced to each other in different layers with reference planes above and below these signal conductors. Coupling of the signals from the generator to the receptor can occur through capacitive coupling or inductive coupling. Capacitive coupling, also known as electrical coupling, occurs due to the difference in the characteristic impedance of the generator (usually 50 or 100 §Ù) and its heavy load (1 k§Ù or more) which results in high voltage difference between the generator and the reference conductor (ground). This leads to the creation of a charge across the generator and the receptor-facing sides and finally results in the electric field coupling between them. On the other hand, inductive coupling, also known as magnetic coupling, occurs when the load is less than the characteristic impedance of the generator, and this thereby results in a heavy current flow through the generator which in return results in a strong magnetic field around itself and so leads to magnetic coupling to the receptor. The aim in this thesis is to measure both the capacitive and inductive coupling load¡¯s impacts on both the edge coupling and the broadside coupling models through crosstalk on the receptor. This thesis starts with the background and corresponding theory and equations to the crosstalk coupling. Later on it tests both the edge- and broadside coupling models with different physical properties exploitation. Inductive and capacitive loads are used to measure the resulting crosstalk coupling. Particularly to see the effect of capacitive and inductive coupling in reality in multi layered PCB, a Sbclin (Broadside coupled striplines) model has been used with different angular placement of the generator. Finally mclin physical models are compared with the simulated models and corresponding differences are discussed. It can be concluded that crosstalk effect increases or decreases with physical properties exploitation. Crosstalk also increases with the wrong termination of the load.

  • 20.
    Kantzon, David
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Lahti, Sebastian
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Over voltage protection device for ROV2014Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Supplying power to equipment always imposes a risk of damaging it. This risk is apparent in every application whether it be an industrial or a home appliance. One of these harmful occurrences is something like lightning which introduces a potentially harmful voltage in the system. To reduce the risk of damage significantly an over-voltage protection device is needed. Devices which deal with this problem are common in any electrical equipment and this report deals with the construction and evaluation of one such unit.

    The device or equipment needing protection in this case is an industrial underwater robot built by Ocean Robotics. In order for this robot to operate safely it needs several protective measures where an over-voltage protection system is one of them. This system provides protection against over-voltages appearing on the main cable supplying the robot, where the input voltage ranges from 200 to 600 volts. As the desired voltage output range from the over-voltage system is 250 to 350 volts it must be able to handle significant power in some cases.

    Due to the restrictions on functionality given by the contractor a novel way of achieving the goals was tested. The completed prototype can only dissipate 70 watts of power which is far from the required 1500 watts which was specified in the sheet of requirements. However, this system could be used to protect equipment with lower requirements for power handling capability and with added time and effort it could possibly meet the requirements for this project as well.

  • 21.
    Skarphagen, Richard
    et al.
    Linköping University, Department of Electrical Engineering. Linköping University, The Institute of Technology.
    Suu, Albin
    Linköping University, Department of Electrical Engineering. Linköping University, The Institute of Technology.
    Utveckling av prototyp för utläsning av sensorvärden från enkortsdator via NFC2014Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The use of phone to check if you are sick or not has just begun, one example of this is that Apple recently released its new ios that contains the app “Health” where you can check how many steps you have taken on a day, check your pulse rate or how many calories you have burnt during the day.

    We simply want to check our health at home with ease so we don’t have to go to the hospital, this requires that our product has to be small and cellpowered and of course cheap.

    This report describes our examwork where we investigate if we can build a blood flow measurement/measuring prototype, it has to be cheap, cellpowered, small and it must have theability to send its information via the protocol NFC.

    We were given a Raspberry Pi, this to keep the price down, and for the NFCsending issue wehad to use Androidphones/tablets with NFC on them. To reach the goal we had to program the Raspberry Pi in C to take care of the information, and make an app for Android in Java that reads the information wirelessly and can show the information on display.

    Late in the project we noticed that our ADC couldn’t handle the probe, wich made us unable to realise the blood flow probe measurements. Therefore our finished product is not the complete product we were hiping for.

    We had to change the probe to a IRdistance sensor, wich we chose because then we would still be able to show that we can send information from a sensor via ADC to Raspberry Pi and then to the phone/tablet.

    Our finished product became a small, cheap and cellpowered distance measurer. This showed us that we have the knowledge to make a small, cheap and cellpowered hospital gear.

    In the future there are big possibilites with what you can do with this  technique for example, check for disease, blood flow, lung capacity just by reading via moving your phone over for example a watch.

  • 22.
    Palomeque, Carlos
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Real-Time Visualization of Construction Equipment Performance2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis is a proof-of-concept project that aims at modify and reuse existing communication protocols of wireless vehicle to vehicle communication in order to build a prototype of a real time graphical application that runs in an embedded environment. The application is a 2D visualization of the flow of material at a quarry and is built on top of existing communication protocols that enable wireless vehicle to vehicle communication according to the 802.11p standard for intelligent transport solutions. These communication protocols have already been used within the Volvo group in other research rojects, but not in a context of a real-time graphical 2D visualization. The application runs on an ALIX embedded motherboard and combined with the necessary hardware represent one node that makes the communication network. The visualization monitors the position of every active node in the network and the flow of material between material locations and crusher that process the material at the quarry. The visualization is implemented in C/C++ using Qt 4.6.2 Graphics View framework.

  • 23.
    Helgesson, Dan
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Nilsson, Emelie
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Comparison and implementation of IPS2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Innomhuspositioneringssystem kan med fördel användas i många olika tillämpningar, allt från sjukhus till shoppingcenter. Denna rapport behandlar olika tekniker och lösningar för att designa ett positioneringssystem. Rapporten tar även upp i detalj hur ett system kan konstrueras av ZigBee kombinerat med dödräkning.

  • 24.
    Arvidsson, Amanda
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Generic Control of Permanent Magnet Synchronous Motors2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    -

  • 25.
    Uhlin, Jakob
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    CAN signal quality analysis and development of the signal processing on a FPGA2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis report is a part of the thesis project conducted by Jakob Uhlin at Syntronic R R and D, Stockholm Sweden. The objective of this thesis is to develop a way to process the signal being sent on a CAN-bus and subsequently analyse its quality and its source in the network. A process of gathering appropriate theories and data has been done, parallel with the development of the analyzer module. The intelligence is implemented in an FPGA through the hardware description language VHDL. In this way, the algorithms can process the data in a real-time domain. The central findings and conclusions have been that is possible to analyze the signal quality of a CAN message properly on a FPGA.

  • 26.
    Skog, Albert
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Westerberg, Karl
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Graphene on Silicon Carbide Chip for Biosensing Applications2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Graphene is a single layer of carbon atoms, laid out in a hexagonal lattice. The material has remarkable properties that opened up several new research areas since its discovery in 2004. One promising field is graphene based biosensors, where researchers hope to create new devices that are smaller, cheaper and more reliable than those based on today’s technology. Among several manufacturing methods, graphene grown on silicon carbide is one of the promising ones for biosensing. A chip design has been developed in order to support research into graphene on silicon carbide as a base material for biosensors. Along with the chip, a holder for electrochemical measurements has been designed and an investigation into the requirements of a custom measurement device for the sensor has been undertaken.

  • 27.
    Juarez, Maribel
    Linköping University, Department of Management and Engineering. Linköping University, The Institute of Technology.
    Structuring Lean Thinking in the Radio Access Network Area2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Customer’ demands, higher quality, faster and safer deliveries are some reasons for unexpected changes in the organizations. It has incremented complexity and cost. Lean production is known as a methodology to make improvements in manufacturing areas such as mentioned above and it is focused on the process of a product. But, Lean Thinking is a management strategy to make improvements in the process of a product or service and it is based on five principles. It allows having the process close to the customer eliminates tasks that do not add value and produces with low costs and high quality. However, there are some concepts ambiguous to be applied effectively to the Radio Access Network area in wireless telecom industry as a service company. Radio Access Network area transmits Radio frequency (RF) signals from the Radio Base Station (RBS) to the user equipment (UE) or mobile phone and is an area to present dynamic changes by high technology innovation. Therefore, the aim of this study is to identify improvements through for the Radio Access Network area.

    This thesis was structured to know how the five Lean principles and Lean tools can be used in the Radio Access Network area and the benefits that it could have. The study was realized through a qualitative research and five semi-structured interviews. A manager, team leaders and engineers of wireless telecom industry vendor and operators were the participants for this study.

    The results of major impact for Lean principles and Lean tools were VSM and Flow principles and Waste as Lean tool found for the Radio Access Network area. Project definition, resource planning and VOC were some improvements revealed for VSM principle. Furthermore, faster and optimal tools, training for engineers, knowledge in software and employee empowerment were some improvements found for Flow principle. Waste Lean tool showed some improvements found on customer’s focus, clear communication and waiting time reduction. Cross functional teams were other aspects that provided quality performance in the projects.

    This study seemingly is a good start for making decisions and for the high technology innovation and dynamic changes for telecom service companies.

  • 28.
    Ali, Rahman
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Design of Building Blocks in Digital Baseband Transceivers for Body-Coupled Communication2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Advances in communication technologies continue to increase information sharing among the people.~Short-range wireless networking technologies such as Bluetooth or ZigBee, which are mainly used for data transfer over short range, will, however, suffer from network congestion, high power consumption and security issues in the future.

    The body-coupled communication (BCC), a futuristic short-range wireless technology, uses the human body as a transmission medium. In BBC channel, a small electric field is induced onto the human body which enables the propagation of a signal between communication devices that are in the proximity or direct contact with the human body. The direct baseband transmission and simple architecture make BCC an attractive candidate for a future short-range wireless communication technology in particular applications such as body area network.

    The main focus of this thesis is on the design and implementation of digital baseband transmitter and receiver for the body-coupled communication. The physical layer (PHY) implementation of the digital baseband transmitter and receiver is inspired from the IEEE 802.3 Ethernet transmission protocol. The digital design is implemented at RTL level using hardware description language (VHDL). The functionality of the digital baseband transmitter and receiver is demonstrated by developing data transfer application layers.

  • 29.
    Khan, Abbas
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Optimization through Co-Simulation of Antenna, Bandpass Filter and Low-Noise Amplifier at 6-9 GHz2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Ultra-wide band (UWB) 6-9 GHz antenna, band pass filter and low-noise amplifier (LNA) optimization using co-simulation of the RF front-end. At higher frequencies, carefully conducted design methodologies are required for RF front-end parameter optimization, such as power gain and low noise figure with low power consumption.

  • 30.
    Wali, Naveen
    et al.
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Radhakrishnan, Balamurali
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Design of a Time-to-Digital Converter for an All-Digital Phase Locked Loop for the 2-GHz Band2013Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    An all-digital phase locked loop for WiGig systems was implemented. The developedall-digital phase locked loop has a targeted frequency range of 2.1-GHz to2.5-GHz. The all-digital phase locked loop replaces the traditional charge pumpbased analog phase locked loop. The digital nature of the all-digital phase lockedloop system makes it superior to the analog counterpart.There are four main partswhich constitutes the all-digital phase locked loop. The time-to-digital converteris one of the important block in all-digital phase locked loop.

    Several time-to-digital converter architectures were studied and simulated. TheVernier delay based architecture and inverter delay based architecture was designedand evaluated. There architectures provided certain short comings whilethe pseudo-differential time-to-digital converter architecture was chosen, becauseof it’s less occupation of area. Since there exists a relationship between the sizeof the delay cells and it’s time resolution, the pseudo-differential time-to-digitalconverter severed it’s purpose.

    The whole time-to-digital converter system was tested on a 1 V power supply,reference frequency 54-MHz which is also the reference clock Fref , and a feedbackfrequency Fckv 2.1-GHz. The power consumption was found to be around 2.78mW without dynamic clock gating. When the clock gating or bypassing is done,the power consumption is expected to be reduced considerably. The measuredtime-to-digital converter resolution is around 7 ps to 9 ps with a load variation of15 fF. The inherent delay was also found to be 5 ps. The total output noise powerwas found to be -128 dBm.

  • 31.
    Nilsson, Petter
    Linköping University, Department of Electrical Engineering, Electronics System.
    Built-in self-test of analog-to-digital converters in FPGAs2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When designing an ADC it is desirable to test its performance at two different points in the development process. The first is characterization and verification testing when a chip containing the ADC has been taped-out for the first time, and the second is production testing when the chip is manufactured in large scale. It is important to have a good correlation between the results of characterization and the results of production testing.

    This thesis project investigates the feasibility of using a built-in self-test to evaluate the performance of embedded ADCs in FPGAs, by using the FPGA fabric to run necessary test algorithms. The idea is to have a common base of C code for both characterization and production testing. The code can be compiled and run on a computer for a characterization test setup, but it can also be synthesized using a high-level synthesis (HLS) tool, and written to FPGA fabric as part of a built-in self-test for production testing. By using the same code base, it is easier to get a good correlation between the results, since any difference due to algorithm implementation can be ruled out. The algorithms include a static test where differential nonlinearity (DNL), integral nonlinearity (INL), offset and gain error are calculated using a sine-wave based histogram approach. A dynamic test with an FFT algorithm, that for example calculates signal-to-noise ratio (SNR) and total harmonic distortion (THD), is also included. All algorithms are based on the IEEE Standard for Terminology and Test Meth- ods for Analog-to-Digital Converters (IEEE Std 1241). To generate a sine-wave test signal it is attempted to use a delta-sigma DAC implemented in the FPGA fabric.

    Synthesizing the C code algorithms and running them on the FPGA proved successful. For the static test there was a perfect match of the results to 10 decimal places, between the algorithms running on a computer and on the FPGA, and for the dynamic test there was a match to two decimal places. Using a delta-sigma DAC to generate a test sine-wave did not prove feasible in this case. Assuming a brick-wall bandpass filter the performance of the delta-sigma DAC is estimated to an SNR of 53dB, and this signal is not pure enough to test the test case ADC with a specified SNR of 60dB.

  • 32.
    Khan, Raja Muhammad Awais
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Zaheer, Sajid
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Design and Implementation of a 7-8 GHz Low-Noise Amplifier2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The thesis describes the LNA design for the European UWB regulations for 6.0-8.5 GHz. The design of low-noise amplifier is a critical step while designing the front-end of the receiver architecture. This work covers the design and simulation of the LNA using the PHEMT transistor ATF-36163. The thesis includes the bias network design, stability analysis, matching network design and layout design of the LNA RF module with layout simulation. The electronic design automation tool, Advance Design System (ADS) is used. After implementation of LNA on a printed circuit board (PCB), the LNA is measured with the help of the vector network analyzer. The simulated noise figure is 1.096 dB and simulated power gain is 9.01 dB at 7.5 GHz and power gain of simulated layout component is 6.5 dB. The measured power gain is 2.36 dB.

  • 33.
    Faisal, Fahad
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Analysis of methods for EMF in-situ measurements of LTE base stations2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to analyze two proposed methods for in-situ measurements of electromagnetic fields transmitted by LTE base stations. One of the methods is based on measurements of physical broadcast channel (PBCH) using basic spectrum analyzer, whereas the other method is based on measurements of the reference signal (RS) using a decoder. Both alternatives are proposed to be used for extrapolation to the maximum electromagnetic field exposure level at full base station traffic load. The analysis is conducted with respect to instrument requirements, accuracy and time requirements. Different instrument settings of the spectrum analyzer and their impact on the measurement results is analyzed and discussed.

    In this work around 70% cases from all the measurements; the spectrum analyzer method overestimate the electric field strength compared with the LTE decoder method. All spectrum analyzer based measurements conducted in the main beam of an antenna at distances of less than 100 m were within ± 20% compared with the decoder results. Measurement results obtained in a reflective environment show that both methods are affected by fading, but significant deviations between the two methods indicate that the spectrum analyzer method is more sensitive to frequency selective fading.

    Based on the results and experiences obtained in this work the following conclusions have been drawn:

    • In the main beam of an antenna and for distances from the antenna of less than 100 m the two methods agree within ± 20 %.
    • When conducting spectrum analyzer based measurements in reflective environments it is important to follow standardized guidelines in order to avoid underestimating results
    • The decoder based method is most suitable when assessing the electric fields within a specific cell, for example to determine the compliance boundary of an antenna, whereas the spectrum analyzer based method is more suitable for general assessment, e.g. measurements in environments such as offices or other areas where no specific antenna is considered and slight deviation is acceptable.
    • The max-hold time for the spectrum analyzer method currently recommended in the latest draft of EN 50492 can be reduced to 5 s.
  • 34.
    Gustafsson, Jessica
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Energieffektiviseringar på ett fjärrvärmenät2012Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Målet med detta examensarbete är att undersöka energiåtgången i Mjölby-Svartådalens Energi AB:s fjärrvärmenät genom att undersöka driftfall och ge förslag på förbättringar. I början av examensarbetet studerades fjärrvärmeprocessen, från värmandet av vattnet tills det kommer till kunden. En viktig del var att förstå hur tryck och flöde samverkar. För att behålla trycket krävs det pumpstationer med jämna mellanrum, för att inte överbelasta motorerna. Förstå hur alla de olika delarna fungerar ihop i fjärrvärmesystemet.

    Studerandet av olika driftfall har inte lett till många bättre alternativ. Vissa fall bättre är andra beroende på vilken situation det handlar om. Det är svårt att ge förslag om energibesparingar samt undersöka motorerna, men med detta examensarbete som grund kan en fördjupning ske på flera tänkbara sätt.

  • 35.
    Zandén, Adam
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Utvärdering av solceller och vindkraft2012Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    According to the evaluations that have been made of the three different solar cell types (polycrystalline, monocrystalline and thin film) and the various models from Sino Sun, PPAM and Schüco the conclusion is that the most expensive solar cell, is not always the best. The differences between Sino Sun and PPAM are so small and along with the price off the last mentioned solar cell which means that Sino Sun’s solar cells are the best choice of solar cell technology that Egen El AB has to offer.

    The different wind power alternatives on Kullen in the city of Katrineholm come in many shapes and method of fabrication. The results have shown that ETC is not a great wind power solution but Svarta Sara, one av Egen El AB’s flagship, is according to the output power effectiveness.

  • 36.
    Ali, Islam
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Iqbal, Wasim
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Performance analysis of various antennas at 2.45 GHz2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this era of technology, there is a swift increase in the number of applications which operate at the Industrial Scientific Medical Band. The applications of this band ranges from home microwave oven to wireless local area networks (WLAN). Therefore, the design of antennas on this band is essential.

    This thesis work revolves around the detailed study and design of various antennas at 2.45 GHz. All the simulation of the antennas was performed using advanced design system (ADS). Microstrip antenna technology is commonly used in antenna design due to its advantages such as low-profile, small size and easy fabrication on printed circuit boards.

    Firstly, various antennas such as rectangular patch, square patch, dipole, inverted F and printed Yagi were designed using ADS and their different performance parameters such as input impedance matching, voltage standing wave ratio (VSWR), input reflection, and gain and directivity were discussed. Dipole antenna, inverted F and printed Yagi were fabricated on printed circuit board (PCB) to compare their measured and simulated results.

    At the end, a conclusion is drawn for different antennas based on their various performance parameters.

  • 37.
    Johansson, Sebastian
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Nyberg, Daniel
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Ritning av industribyggnad med dokumentation av elcentraler2012Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Vid vissa tillfällen kan man som elektriker behöva bryta strömmen snabbt för en fastighet, pågrund av olika faktorer. Finns då inte något dokument som visar var centralerna är placerade i fastigheten, vilka centraler som är aktiva eller vilken central som är huvudcentral medför det ett problem. För att underlätta detta har YIT bett oss att rita ett nytt huvudledningsschema för en industrifastighet på Tenngatan 11 i Norrköping.

    Då de ritningar som redan finns på fastigheten är gamla och inte omfattar ombyggnader i lokalerna ska en ny planritning på fastigheten göras där vi även dokumenterar var alla centraler och undercentraler är placerade. Den nya planritningen kommer även att medföra att fastighetsägaren får de exakta ytorna på de olika lokalerna.

  • 38.
    Fornander, Gustaf
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Konstruktion av nätstation2012Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport behandlar ett examensarbete utfört av Gustaf Fornander våren 2012. Där uppgiften som låg till grund för examensarbetet var behov av en konstruktör för elkonstruktion av en nätstation på Scania i Oskarshamn. Uppgifterna blev att ta fram arbetsritningar, apparatlistor och reläskyddsinställningar. Projektet som drevs som en totalentreprenad av Sydsvenska Elanläggningar resulterade i en komplett nätstation med högspänningsställverk, transformator och lågspänningsställverk.

  • 39.
    Chen, Yi-Ching
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    Co-design of Fault-Tolerant Systems with Imperfect Fault Detection2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In recent decades, transient faults have become a critical issue in modernelectronic devices. Therefore, many fault-tolerant techniques have been proposedto increase system reliability, such as active redundancy, which can beimplemented in both space and time dimensions. The main challenge of activeredundancy is to introduce the minimal overhead of redundancy and to schedulethe tasks. In many pervious works, perfect fault detectors are assumed to simplifythe problem. However, the induced resource and time overheads of suchfault detectors make them impractical to be implemented. In order to tacklethe problem, an alternative approach was proposed based on imperfect faultdetectors.

    So far, only software implementation is studied for the proposed imperfectfault detection approach. In this thesis, we take hardware-acceleration intoconsideration. Field-programmable gate array (FPGA) is used to accommodatetasks in hardware. In order to utilize the FPGA resources efficiently, themapping and the selection of fault detectors for each task replica have to be carefullydecided. In this work, we present two optimization approaches consideringtwo FPGA technologies, namely, statically reconfigurable FPGA and dynamicallyreconfigurable FPGA respectively. Both approaches are evaluated andcompared with the proposed software-only approach by extensive experiments.

  • 40.
    Tang, Dennis
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Evaluation of EDA tools for electronic development and a study of PLM for future development businesses2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Electronic Design Automation (EDA) tools are today very capable computer programs supporting electronic engineers with the design of printed circuit board (PCB). All tools have their strengths and weaknesses; when choosing the right tool many factors needs to be taken into consideration aside from the tools themselves. Companies need to focus on the product and revenues for a business to be viable. Depending on the knowledge and strengths of the company, the choice of tools varies. The decision should be based on the efficiency of the tools and the functions necessity for the company rather than the price tags. The quality and availability of support for the tools, training costs, how long will it take to put the tool in operation and present or future collaboration partners is equally important factors when deciding the right tool. The absence of experience and knowledge of the current tool within a company is a factor which could affect important operation; therefore it is important to provide training and education on how to use the tool to increase its efficiency. Providing training and education can be a large expense, but avoids changes within and makes the business competitive. The choice of EDA tool should be based on the employed engineer’s current knowledge and experience of the preferred tool. If the employed engineer’s knowledge and experience varies too much, it might be preferable to make a transition to one of the tool by training and education. Product lifecycle management (PLM) is a data management system and business activity management system which focuses on the lifecycle of a product. To manage the lifecycle of a product it is necessary to split the lifecycle into stages and phases for a more manageable and transparent workflow. By overseeing a product’s entire lifecycle there are benefits which affects many areas. PLM greatest benefits for EDA are collaboration across separate groups and companies by working together through a PLM platform, companies can forge strong design chains that combine their best capabilities to deliver the product to the customers. This report is a study on evaluating which EDA suits the company with consideration of the employed engineer’s demands, requests and competence. The interests in PLM made the company suggest a short theory study on PLM and EDA benefits.

  • 41.
    Moreno Arocena, Ugaitz
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Energy Consumption Studies for 3G Traffic Consolidation on Android using WiFi and Bluetooth2014Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Mobile phones have evolved from being devices just to make phone calls to become smartphones with added capabilities like surfing the network. Wireless communication has played a very important role in the evolution of smartphones.

    The work in this thesis aims to study the potential to reduce the energy consumption of the 3G communications by using a hybrid architecture. An idea first presented in the paper by Vergara and Nadjm-Tehrani [1]. This architecture consists of a group of nodes that communicate using WiFi or Bluetooth to forward their traffic using one node's 3G interface. In this thesis the named energy sharing scheme is implemented on Android mobile devices and experiments have been performed using a number of realistic traces to assess achievable gains and the energy footprint of the scheme itself.

    Even though communication technologies, screen features, multimedia capabilities, or processing power have been taken to the highest level, phones' batteries have not improved at the same speed. Nowadays battery lifetime has become a major issue with respect to cellular communication.

    With 3G communications Internet connection anytime and anywhere is provided to the terminals but this technology is optimized for peak performance whereas in underutilization it wastes a lot of energy. This makes it a big black hole from power consumption point of view when transmitting small amounts of data.

  • 42.
    Löfgren, Johanna
    Linköping University, Department of Electrical Engineering. Linköping University, The Institute of Technology.
    Mjukvara som hanterar kommunikation mot mjukvara i en dataloggningsenhet2014Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    I detta projekt har mjukvara till en dator utvecklats, denna mjukvara är en prototyp för hur funktionaliteten i en framtida handhållen enhet för kommunikation mot LoggerReadOut-programmet bör se ut, samt eftersträvas vid vidareutveckling. Under projektets gång har dels utveckling av en Android applikation i programmeringsspråket Java och utvecklingsmiljön Eclipse genomförts. Programmeringen av applikationen för Android har kommit att revideras till utveckling av mjukvara i programmeringsspråket Python. Den mjukvara som utvecklas i Python utvecklas för att verka som en prototyp på funktionalitet bör se ut i en applikation för Android som detta projekt kan stå som bas för.

    Det program som skapats, smartDustHandheldUnit, hanterar kommunikationen med LoggerReadOut-programmet och mellan dessa två program kan auktoriserad anslutning etableras, data och information kan hämtas samt så kan anslutningen som skapats stängas ned. Utöver detta hanterar programmet upp- samt nedladdning till och från två .php-sidor anpassade för ändamålet. Dessutom finns funktionalitet för att kontrollera vilket operativsystem enheten använder.   

  • 43.
    Elyasi, Shiva
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Katuri, Sesanka
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Distributed Algorithms for Rate Allocation with Successive Interference Cancellation2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In wireless networking, receivers are typically assumed to be utilizing single-user decoding. Still, for more than twenty years we know that we can take advantage of interference by multi-user decoding. The Interference Cancellation (IC) technique has, of late, gained interest in the wireless networking context. Previous works [3] have shown considerable potential gains by leveraging optimal collaborative rate control to enable IC, focusing on the low Signal-to-Noise Ratio (SNR) regime. Here, we present centralized and distributed rate control algorithms, enabling IC, to increase system throughput. We consider a system where the receivers can apply multi-user decoding to perform IC and the rates are provided by a step-wise function of the Signal to Interference-and-Noise Ratio (SINR), in realistic conditions. We conduct a thorough simulation study comparing the proposed algorithms using two IC techniques, and deliver results that indicate significant system throughput gains.

  • 44.
    Marzetta, Thomas L.
    et al.
    Bell Labs, Alcatel‐Lucent, NJ, USA .
    Caire, Giuseppe
    Politecn Torino, Turin, Italy.
    Debbah, Merouane
    Institute Eurecom, Sophia Antipolis, Italy.
    Chih-Lin, I
    China Mobile Research Institute, Beijing, China .
    Mohammed, Saif K.
    Linköping University, Department of Electrical Engineering, Communication Systems. Linköping University, The Institute of Technology. IIT Delhi, India .
    Special issue on Massive MIMO2013In: Journal of Communications and Networks, ISSN 1229-2370, Vol. 15, no 4, 333-337 p.Article in journal (Other academic)
    Abstract [en]

    Demand for wireless communications is projected to grow by more than a factor of forty or more over the next five years. A potential technology for meeting this demand is Massive MIMO (also called Large-Scale Antenna Systems, Large-Scale MIMO, ARGOS, Full-Dimension MIMO, or Hyper-MIMO), a form of multiuser multipleantenna wireless which promises orders-of-magnitude improvements in spectral-efficiency over 4G technology, and accompanying improvements in radiated energy-efficiency. The distinguishing feature of Massive MIMO is that a large number of service-antennas ?? possibly hundreds or even thousands ?? work for a significantly smaller number of active autonomous terminals. Upsetting the traditional parity between service antennas and terminals in this manner is a game-changer: The simplest multiplexing precoding and decoding algorithms can be nearly optimal, expensive ultra-linear forty-Watt power amplifiers are replaced by many low-power units, and the favorable action of the law of large numbers can greatly facilitate power-control and resource-allocation.

  • 45.
    Ragavan, Rengarajan
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    Reconfigurable FSM for Ultra-Low Power Wireless Sensor Network Nodes2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Wireless sensor networks (WSN) play an important role in today’s monitoring and controlsystems like environmental monitoring, military surveillance, industrial sensing and control, smarthome systems and tracking systems. As the application of WSN grows by leaps and bounds, there is anincreasing demand in placing a larger number of sensors and controllers to meet the requirements. Theincreased number of sensors necessitates flexibility in the functioning of nodes. Nodes in wirelesssensor networks should be capable of being dynamically reconfigured to perform various tasks is theneed of the hour.In order to achieve flexibility in node functionality, it is common to adopt reconfigurablearchitecture for WSN nodes. FPGA-based architectures are popular reconfigurable architectures bywhich WSN nodes can be programmed to take up different roles across time. Area and power are themajor overheads in FPGA based architectures, where interconnect consumes more power and area thanlogic cells. The contemporary WSN standard requires longer battery life and micro size nodes for easyplacement and maintenance-free operation for years together.Three solutions have been studied and evaluated to approach this problem: 1) Homogenousembedded FPGA platform, 2) Power gated reconfigurable finite state machines and 3) Pass transistorlogic (PTL) based reconfigurable finite state machines. Embedded FPGA is a CMOS 65nm customdeveloped small homogenous FPGA which holds the functionality of the WSN nodes and it will bedynamically reconfigured from time to time to change the functionality of the node. In Power gatedreconfigurable FSM architecture, the functionality of the node is expressed in the form of finite statemachines, which will be implemented in a LUT based power gated design. In PTL based reconfigurablefinite state machine architecture, the finite state machines are completely realized using PTL basedcustom designed sets of library components. Low power configuration memory is used to dynamicallyreconfigure the design with various FSMs at different times.

  • 46.
    Attaullah, Muhammad
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    An LTE implementation based on a road traffic density model2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The increase in vehicular traffic has created new challenges in determining the behavior of performance of data and safety measures in traffic. Hence, traffic signals on intersection used as cost effective and time saving tools for traffic management in urban areas. But on the other hand the signalized intersections in congested urban areas are the key source of high traffic density and slow traffic. High traffic density causes the slow network traffic data rate between vehicle to vehicle and vehicle to infrastructure. To match up with the emerging technologies, LTE takes the lead with good packet delivery and versatile to changes in the network due to vehicular movements and density.

    This thesis is about analyzing of LTE implementation based on a road traffic density model. This thesis work is aimed to use probability distribution function to calculate density values and develop a real traffic scenario in LTE network using density values.

    In order to analyze the traffic behavior, Aimsun simulator software has been used to represent the real situation of traffic density on a model intersection. For a realistic traffic density model field measurement were used for collection of input data. After calibration and validation process, a close to realty results extracted and used a logistic curve of probability distribution function to find out the density situation on each part of intersection. Similar traffic scenarios were implemented on MATLAB based LTE system level simulator.

    Results were concluded with the whole traffic scenario of 90 seconds and calculating the throughput at every traffic signal time and section.

    It is quite evident from the results that LTE system adopts the change of traffic behavior with dynamic nature and allocates more bandwidth where it is more needed.

  • 47.
    Kalered, Olle
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Development of analysis system for dynamic signals2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Den här rapporten presenterar ett examensarbete där ett mätdatainsamlingssystem för dynamiska signaler har skapats. Arbetet har utförts på Siemens Industrial Turbomachinery AB. Problemet är av sådan natur att tre olika typer av signaler analyseras. Dessa signaler är dels dynamiska signaler med ett intressant frekvensinnehåll mellan 10 och 10 000 Hz, dels likspänningssignaler och dels varvtalssignaler. Dessa signaler datasamplas och analyseras med avseende på både tids- och frekvensinnehåll. Resultatet skickas vidare till en server med en uppdateringsfrekvens kring 1 Hz. Arbetet har inneburit att en kravanalys av systemet har tagits fram utifrån ett redan existerande system och från intervjuer med tänkta användare av systemet. Utifrån den skapade kravprofilen valdes lämplig hårdvara och mjukvara implementerades med hjälp av LabVIEW. Resultatet blev ett system som lever väl upp till förväntningarna.

  • 48.
    Subramanians, Sankar Saravanan
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Geo-based Mobility Control for Mobile Traffic Simulators2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Most mobile traffic simulators of today depend on the user to supply the mobility behavior of the simulated UEs. This becomes a problem when certain wanted mobility characteristics are to be tested, since the user have to go trough a trial-and-error procedure to come up with the proper mobility behavior. This thesis presents two approaches to mobility control, where the aim is to control UE mobility based on certain mobility characteristics supplied by the end user. The first approach introduces the concept of assigning tasks to UEs, e.g. “cross cell border” or “move to a certain cell”. Furthermore, concepts from control theory are borrowed to control the task assignment process, making it more dynamic and robust. The second approach iteratively calculate movement patterns for the UEs in an area until it finds a movement pattern that has a high probability of satisfying the user’s requested mobility characteristics.

  • 49.
    Nawaz, Mohsin
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Exploiting Tracking Area List Concept in LTE Networks2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Signaling Overhead has always been a concern for network operators. LTE offers many improvements aimed at improved network performance and management. This thesis exploit Tracking Area List (TAL) concept in LTE networks. An algorithm to design TAL using UE traces is developed. The performance of TAL design is compared to conventional TA design. Performance is also compared with rule of thumb TAL design which is another approach to designing TAL

  • 50.
    Dahlström, Patrik
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Geo-based Mobility Control for Mobile Traffic Simulators2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Most mobile traffic simulators of today depend on the user to supply the mobility behavior of the simulated UEs. This becomes a problem when certain wanted mobility characteristics are to be tested, since the user have to go trough a trial-and-error procedure to come up with the proper mobility behavior. This thesis presents two approaches to mobility control, where the aim is to control UE mobility based on certain mobility characteristics supplied by the end user.

    The first approach introduces the concept of assigning tasks to UEs, e.g. “cross cell border” or “move to a certain cell”. Furthermore, concepts from control theory are borrowed to control the task assignment process, making it more dynamic and robust.

    The second approach iteratively calculate movement patterns for the UEs in an area until it finds a movement pattern that has a high probability of satisfying the user’s requested mobility characteristics.

    In order to properly evaluate these two approaches a prototype simulator was developed, as well as a virtual network controller to be tested. This test environment simulate a simplified tree network topology.

    Both approaches was tested to control the total number of handovers per second in a simulated area. They both show high accuracy and acceptable precision. Additionally, the task based approach was used to control the cell utilization in a target cell. However, the cell utilization tests showed a lower accuracy and precision than the handover rate control tests.

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