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  • 5401. Hult, Tommy
    et al.
    Mohammed, Abbas
    Estimation of the TOA performance of Loran-C2004Conference paper (Refereed)
    Abstract [en]

    Loran-C is a navigational aid that relies on the ability to make correct estimates of the Times of Arrival (TOAs) of signals received over a noisy radio channel. How good is the performance of Loran-C in this respect? Is it close to optimal? Are there perhaps better estimation techniques available than we currently employ? In this paper we use Estimation Theory to find the optimal limit of the accuracy of TOA estimates, for a given signal-to-noise ratio (SNR). Specifically, we compute the Cramer-Rao Lower Bound (CRLB) which specifies the absolute minimum error variance that can be achieved by an unbiased estimator. From the CRLB we can estimate the best repeatable accuracy that can be attained using a set of TOAs. We compute here the CRLBs for the TOA of a Loran-C signal with both Additive White Gaussian Noise (AWGN) and Additive Coloured Gaussian Noise (ACGN). We then employ the Maximum Likelihood Estimator (MLE) and compare its results with that of CRLB. Simulation results show that the MLE approaches the minimum variance obtained by CRLB for SNR values of practical and reliable Loran-C operation.

  • 5402. Hult, Tommy
    et al.
    Mohammed, Abbas
    HAP Diversity and Compact MIMO Antennas for High Data Rate Communications2006Conference paper (Refereed)
    Abstract [en]

    In this paper we address the potential gain of using compact MIMO antenna array configurations in conjunction with HAP diversity and OFDM techniques in order to increase the data rates in HAP communication systems. Simulation results show that the MIMO system provides superior performance as compared to the single HAP case.

  • 5403. Hult, Tommy
    et al.
    Mohammed, Abbas
    Indoor Propagation Simulation using FEM for Short-Range Wireless Communication Systems Operating at 2.4 GHz2005Conference paper (Refereed)
    Abstract [en]

    In this paper we investigate the wave propagation effects of a short-range wireless device, like the Bluetooth, in an indoor office environment. Specifically, we investigate line of sight (LOS) and non line of sight (NLOS) propagation scenarios and verify the theoretical statistics of the fading using real measurements and finite element method (FEM) simulations of the environment. The simulations are also used for assessing the impact on propagation when doors are opened or closed. In addition, we also investigate the improvement in performance resulting from receive diversity gain of a system employing multiple receive antennas with various combining techniques.

  • 5404. Hult, Tommy
    et al.
    Mohammed, Abbas
    MIMO ANTENNA APPLICATIONS FOR HIGH ALTITUDE PLATFORMS2006Conference paper (Refereed)
    Abstract [en]

    In this paper we address the potential gain of using compact MIMO antenna array configurations in conjunction with HAP (High Altitude Platforms) diversity techniques in order to increase the data rates in HAP communication systems. Simulation results show that the MIMO system provides superior performance as compared to the single HAP case.

  • 5405. Hult, Tommy
    et al.
    Mohammed, Abbas
    MIMO Antenna Applications for LEO Satellite Communications2005Conference paper (Refereed)
    Abstract [en]

    This paper addresses the potential gain of using multiple antennas and MIMO-OFDM techniques in order to increase the bandwidth efficiency in satellite communication systems. In particular, we consider the increase in channel capacity that is possible by exploiting satellite and polarization diversity. In addition, we investigate the effect of using different compact MIMO polarization antenna configurations and power control on the information theoretic capacity of the total transmission channel of the satellite system.

  • 5406. Hult, Tommy
    et al.
    Mohammed, Abbas
    MIMO applications for interference mitigation in multiple high altitude platform WCDMA systems2009Conference paper (Refereed)
    Abstract [en]

    In this paper we investigate the possibility of multiple HAP coverage of a common cell area. In particular we study the uplink system performance since it is considered as a worst case scenario. In order to obtain further enhancement (interference mitigation) we also apply space-time diversity techniques, such as Single-Input Multiple-Output (SIMO) receive diversity or Multiple-Input Multiple-Output (MIMO) diversity, to improve the spectrum reuse in the multiple HAP scenario. We will show the level of improvement using SIMO and MIMO algorithms, the practical limits on the number of HAPs and SIMO/MIMO system dimension in response to traffic demands and the type of service used.

  • 5407. Hult, Tommy
    et al.
    Mohammed, Abbas
    MIMO for HAPs: an idea whose time has come2006Conference paper (Refereed)
    Abstract [en]

    In this paper we address the potential gain of using compact MIMO antenna array configurations in conjunction with HAP diversity techniques in order to increase the data rates in HAP communication systems. Simulation results show that the MIMO system provides superior performance as compared to the single HAP case

  • 5408. Hult, Tommy
    et al.
    Mohammed, Abbas
    MULTIPATH PROPAGATION ASSESSMENT FOR A 2.4 GHZ SHORT-RANGE WIRELESS COMMUNICATION SYSTEM2006Conference paper (Refereed)
    Abstract [en]

    In this paper we assess the effects of multipath propagation on the link performance of a short-range wireless device, like the Bluetooth, in an indoor office environment. Specifically, we analyze the non line of sight (NLOS) propagation scenario and confirm the theoretical statistics of the fading using real measurements and finite element method (FEM) simulations of the environment. The simulations are also used for assessing the impact of multipath propagation when doors are opened or closed. In addition, we also investigate the improvement in performance resulting from receive diversity gain of a system employing multiple receive antennas with various combining techniques.

  • 5409. Hult, Tommy
    et al.
    Mohammed, Abbas
    Novel Applications of MIMO Antenna System for Active Suppression of Electromagnetic Fields2005Report (Other academic)
    Abstract [en]

    Active suppression of noise and vibrations is a well established field of research with many applications in acoustic and mechanical industries. In this report we test some of these active control methods combined with MIMO antenna system in order to assess their validity and performance when applied to electromagnetic fields. The application that we evaluated is a model of a mobile phone equipped with one ordinary transmitting antenna and a number of actuator-antennas which purpose is to cancel out the electromagnetic field at a specific volume in space (e.g. at the human head) while maintaining a predefined level of the overall output power of the system. This power control is achieved through the use of a quadratic constraint on the active control algorithm. In addition, we will also investigate the impact of MIMO antenna parameters and carrier frequency on the performance of the system. Simulation results show the promise of using the adaptive control algorithms and MIMO system to attenuate the electromagnetic field power density.

  • 5410. Hult, Tommy
    et al.
    Mohammed, Abbas
    Performance Evaluation of Adaptive Signal Processing and MIMO Antenna System for the Reduction of Electromagnetic Field Density2007Conference paper (Refereed)
  • 5411. Hult, Tommy
    et al.
    Mohammed, Abbas
    Power Constrained Active Suppression of Electromagnetic Fields Using MIMO Antenna System2004Conference paper (Refereed)
  • 5412. Hult, Tommy
    et al.
    Mohammed, Abbas
    Power Constrained Space-Time Processing for Suppression of Electromagnetic Fields2005In: Journal of Communication Software and Systems, ISSN 1845-6421, E-ISSN 1846-6079, Vol. 1, no 1Article in journal (Refereed)
    Abstract [en]

    Active suppression of noise and vibrations is a well established field of research with many applications in acoustic and mechanical industries. In this paper we investigate the possibility of applying these adaptive active control methods with the aim of lowering the electromagnetic power density at a specific volume in space using the superposition principle and space-time processing employing the full MIMO (Multiple Input Multiple Output) antenna system setup. The application that we evaluated is a model of a mobile phone equipped with one ordinary transmitting antenna and two actuator-antennas which purpose is to cancel out the electromagnetic field at the human head while maintaining a predefined level of the overall output power of the system. This power control is achieved through the use of a quadratic constraint on the active control algorithm. Simulation results show the promise of using the adaptive control algorithms and MIMO system to attenuate the electromagnetic field power density

  • 5413. Hult, Tommy
    et al.
    Mohammed, Abbas
    Suppression of EM Fields using Active Control Algorithms2004In: Radioengineering, ISSN 1210-2512, E-ISSN 1805-9600, Vol. 13, no 3, p. 22-25Article in journal (Refereed)
    Abstract [en]

    Active methods for attenuating acoustic pressure fields have been successfully used in many applications. In this paper we investigate some of these active control methods in combination with a MIMO antenna system in order to assess their validity and performance when applied to electromagnetic fields. The application that we evaluated in this paper is a model of a mobile phone equipped with one ordinary transmitting antenna and two actuator-antennas which purpose is to reduce the electromagnetic field at a specific area in space (e.g. at the human head). Simulation results show the promise of using the adaptive active control algorithms and MIMO system to attenuate the electromagnetic field power density.

  • 5414. Hult, Tommy
    et al.
    Mohammed, Abbas
    The Effect of Mutual Coupling on a High Altitude Platform Diversity System Using Compact Antenna Arrays2010In: International Journal of Antennas and Propagation, ISSN 1687-5869, E-ISSN 1687-5877, Vol. 2010Article in journal (Refereed)
    Abstract [en]

    We analyze the destructive effects of mutual coupling and spatial correlation between the separate antenna elements on a combined diversity system consisting of multiple HAPs (High-Altitude Platforms) employing various compact MIMO (Multiple-Input Multiple-Output) antenna array configurations, in order to enhance the mutual information in HAP communication links. In addition, we assess the influence of the separation angle between HAPs on system performance, and determine the optimal separation angles that maximize the total mutual information of the system for various compact MIMO antennas. Simulation results show that although the mutual information is degraded by mutual coupling and spatial correlation, the proposed HAP diversity system still provides better performance compared to a nondiversity system for all tested scenarios.

  • 5415. Hult, Tommy
    et al.
    Mohammed, Abbas
    THE IMPACT OF MIMO ANTENNA SYSTEM AND CARRIER FREQUENCYON ACTIVE CONTROL SUPPRESSION OF ELECTROMAGNETIC FIELD2004Conference paper (Refereed)
    Abstract [en]

    There have been several studies done, with conflicting results, on the effects of cell-phone radiation on the human body. The amount of radiation emitted from most cell phones is very minute. However, given the close proximity of the phone to the head, it is entirely possible for the radiation to cause harm. If you want to be on the safe side, the easiest way to minimize the radiation you are exposed to is to position the antenna as far from your head as possible. Utilizing a hands-free kit, a car-kit antenna or a cell phone whose antenna is even a couple of inches farther from the head can do this most effectively. This paper makes a contribution to that discussion by proposing a new approach by employing adaptive active control algorithms combined with a Multiple-Input Multiple-Output (MIMO) antenna system to suppress the electromagnetic field at a certain area in space. We will also investigate the effects of the size and number of MIMO antenna elements and test the algorithms at different carrier frequencies (e.g., other GSM bands and UMTS).

  • 5416. Hult, Tommy
    et al.
    Mohammed, Abbas
    Theoretical Analysis and Assessment of Depolarization Effects on the Performance of High Altitude Platforms2008Conference paper (Refereed)
  • 5417. Hult, Tommy
    et al.
    Mohammed, Abbas
    Falletti, Emanuela
    Sellone, Fabrizio
    Analysis of Depolarizing Effects and Impact on the Performance of a Multiple Satellite System Employing Polarization Diversity2007Conference paper (Refereed)
  • 5418. Hult, Tommy
    et al.
    Mohammed, Abbas
    Falletti, Emanuela
    Sellone, Fabrizio
    Multi-Antenna Multi-HAP Channel Model for Space-Polarization2008Conference paper (Refereed)
  • 5419. Hult, Tommy
    et al.
    Mohammed, Abbas
    Grace, David
    WCDMA Coverage Enhancement from Multiple High Altitude Platforms2008Conference paper (Refereed)
  • 5420. Hult, Tommy
    et al.
    Mohammed, Abbas
    Grace, David
    Yang, Zhe
    Performance of a Multiple HAP System Employing Multiple Polarization2006Conference paper (Refereed)
  • 5421. Hult, Tommy
    et al.
    Mohammed, Abbas
    Nordebo, Sven
    Active Suppression of Electromagnetic Fields Using a MIMO Antenna System2003Conference paper (Refereed)
    Abstract [en]

    Active suppression of noise and vibrations is a well established field of research with many applications in acoustic and mechanical industries. In this paper we test some of these active control methods in order to assess their validity and performance when applied to electromagnetic fields. The application that we evaluated is a model of a mobile telephone equipped with one ordinary transmitting antenna and two actuator-antennas which purpose is to cancel out the electromagnetic field at a specific point in space (e.g. at your head).

  • 5422. Hult, Tommy
    et al.
    Mohammed, Abbas
    Yang, Zhe
    Grace, David
    Performance of a multiple HAP system employing multiple polarization2010In: Wireless Personal Communications, Springer , 2010, Vol. 52, no 1, p. 105-117Conference paper (Refereed)
    Abstract [en]

    In this paper we address the potential gain of using compact MIMO antenna array configurations in conjunction with HAP (High Altitude Platforms) diversity techniques in order to increase the data rates in HAP communication systems. We will also investigate the effects of spatial correlation and mutual coupling between the separate antenna elements on system performance. Simulation results show that although the capacity is degraded by correlation and mutual coupling, we still achieve significant capacity gain compared to the single HAP case. In addition, we evaluate the performance of the system for different separation angles between HAPs, and determine the optimal separation angle that maximizes the total capacity of the system. © 2008 Springer Science+Business Media, LLC.

  • 5423.
    Hultberg, Jenny
    et al.
    Blekinge Institute of Technology, School of Management.
    Klarenius, Karna
    Blekinge Institute of Technology, School of Management.
    Liljekvist, Per
    Blekinge Institute of Technology, School of Management.
    Arbetstidsförkortning: för ökad arbetstillfredsställelse och bättre relationer.2004Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    Background: Already in the 16th century Owen discussed that it was not a good idea to have children working long working hours in three shifts. This approach was introduced at his factory, but was also given a lot of criticism. First in 1962 the idea of 6-hours working day was awakened in Sweden. Since then there has been a number of attempts, among them at the city of Helsingborg´s and Höganäs´ elder care as well at Toyota Center in Mölndal. Problem: Today’s companies are focused on traditional measurements, for example profitability and productivity, even when it comes to shorter working hours. On the other hand, there is not much investigated regarding the so called inner values, such as work satisfaction and relations. We have not found any study that deals with the result of shortened working hours and how it has effected work satisfaction and relation in an organization. Purpose: By studying the psychological abilities; work environment and motivation as well as the sociological abilities; leadership, group and conflict in two companies, we intended to see if there had been any changes in the inner values; work satisfaction and relations through shortened working hours. Method: The study has started out from a qualitative method in which phone interviews have been used for collecting data. The interviews have been carried out at AWJ-Tryck AB and Stora Enso Kvarnsveden AB. We have chosen to study the inner values from the employee’s point of view, but to get a picture of how the change has affected the employees we have chosen to interview supervisors and people from the board as well. Conclusions: The employee’s experiences with shorter working hours is that they are more motivated, which also have led to an increased work satisfaction. Besides that the social part of the work environment works better today. When these factors work in a company the employees feel more motivated which makes them perform better. The answer to our research question is that the employee’s inner values; work satisfaction and relations, shows a positive result in collaboration with shorter work hours.

  • 5424.
    Hultgren, Anders
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Electrical Engineering.
    Bui, S.
    Linnér, Jörgen
    Ranstad, Per
    Lenells, Matz
    Fault tolerant high voltage resonant power converter application2013Conference paper (Refereed)
    Abstract [en]

    A high voltage and high power fault tolerant application of a resonant converter is presented. The resonant converter load shows frequent short circuits making the load voltage drop to zero within some us, implying high stress on the main circuit components. A load voltage short circuit fault tolerant system is suggested by including a novel way of augmenting the controller with a load voltage estimator. The estimator can detect load voltage short circuit and will then be a part of a fault tolerant high voltage resonant converter.

  • 5425.
    Hultgren, Anders
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Electrical Engineering.
    Kulesza, Wlodek
    Blekinge Institute of Technology, School of Engineering, Department of Electrical Engineering.
    Nilsson, Magnus
    Walther, Björn
    Integration av matematik och teknik på ingenjörsutbildningar2009Conference paper (Refereed)
    Abstract [en]

    An possible integration of mathematics and applications within engineering is presented. The integration method has been used at The university of Kalmar. The method is described and experiences are presented.

  • 5426.
    Hultgren, Anders
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Electrical Engineering.
    Melin, Jan
    Ranstad, Per
    Asymmetric Limit Cycles in an Industrially Applied Controlled Resonant Converter2009Conference paper (Refereed)
    Abstract [en]

    An industrially applied LCC power converter is modelled as a hybrid system. It is found that the hybrid system given a parameter set up and different initial conditions has three different limit cycles, one unstable and two asymmetric stable limit cycles. Effects of the asymmetric limit cycles are considered.

  • 5427. Hultgren, Anders
    et al.
    Melin, Jan
    Ranstad, Per
    Limit cycle control of an industrially applied resonant converter modelled as a hybrid system2011Conference paper (Refereed)
    Abstract [en]

    Limit cycle control of an industrially applied high power, high voltage resonant power converter is modelled as a hybrid system. It is found that the hybrid system with three continuous states and one logic state given a parameter set up and different initial conditions has a rich solution set indicating possible problems in the industrial application. The solution set are one central closed trajectory and two asymmetric types of limit cycles.

  • 5428. Hultgren, Anders
    et al.
    Melin, Jan
    Ranstad, Per
    Limit Cycles in an Industrially Applied Hybrid System2010Conference paper (Refereed)
    Abstract [en]

    An industrially applied LCC power converter is modelled as a hybrid system. It is found that the hybrid system with three continuous states and one logic state given a parameter set up and different initial conditions has among other solutions one central closed trajectory and two types of limit cycles, on the left and the right side. The other solutions are indicated.

  • 5429. Hultgren, Anders
    et al.
    Nilsson, Magnus
    Kulesza, Wlodek
    Walther, Björn
    Integration av matematik och teknik på ingenjörsutbildningar2008Conference paper (Other academic)
    Abstract [sv]

    I detta bidrag presenterar vi en uppläggning av integrerade kurser i matematik och tillämpningar, vilken använts inom högskoleingenjörsutbildningen vid Högskolan i Kalmar. Kursverksamheten, som bedrivs inom ramen för kurspaketet ingenjörsvetenskap, tillgodoser såväl behovet av att betona matematikens roll som ett generellt och abstrakt verktyg för problemlösning som behovet av att ge studenterna bra baskunskaper i matematik i anslutning till möjliga tillämpningsområden.

  • 5430.
    Hultgren, Annika
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Johansson, Eva
    Blekinge Institute of Technology, School of Health Science.
    Patienters upplevelser ur ett livsvärldsperspektiv efter genomgången kranskärlsoperation: Litteraturstudie2009Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Kranskärlsoperationer är idag ett vanligt förekommande kirurgiskt ingrepp. Årligen opereras 4200 personer i Sverige. Studier har visat att patienters upplevelser efter en genomgången kranskärlsoperation många gånger är komplicerade, med ökade behov av support och besvär såsom minnesstörningar, nedstämdhet och fysiska besvär. Syftet med studien var att belysa patienters upplevelser ur ett livsvärldsperspektiv efter genomgången kranskärlsoperation. Upplevelserna speglade tiden på sjukhuset och upplevelser i hemmet efter operationen. Metoden var en systematisk litteraturstudie som inbegrep åtta artiklar med kvalitativ analysmetod. Artiklarna bestod av intervjuer gjorda med patienter upp till sju år efter genomgången kranskärlsoperation, och analysen genomfördes utifrån Graneheim & Lundmans beskrivning av kvalitativ innehållsanalys. Resultatet mynnade ut i tre kategorier: upplevelser av fysiska förändringar, patienters känslor och tankeupplevelser samt betydelsen av socialt nätverk. Många av patienterna beskrev oväntade komplikationer som nedsatt koncentrationsförmåga, minnesförlust och att det tog lång tid att återfå en normal fysisk förmåga igen. Flera upplevde återgången till det normala som en lång process, ”transition” där det krävdes både fysisk som psykisk uthållighet. Några patienter tyckte att operationen hade uppfyllt mer än vad de förväntat sig, medan andra hade väntat sig mer. Vikten av socialt stöd och uppmuntran beskrevs som en viktig del för att kunna uppnå ett bra resultat i rehabiliteringen. Studien visade på hur patientens livsvärld påverkades efter en kranskärlsoperation och betydelsen av utökad information till de patienter som upplevde oro, ängslan eller var instabila fysiskt eller psykiskt, vilket kunde vara ett sätt att underlätta återgången till vardagen efter operationen. Slutsatsen blev att man bör utöka informationen till patienterna så de blir mer förberedda inför återhämtningen.

  • 5431.
    Hultgren, Per
    Blekinge Institute of Technology, School of Management.
    The Motivating Suggestion System2008Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    This case study investigates the suggestion system of a manufacturing plant with the purpose of getting insight about how a suggestion system should be designed to support the continuous improvement discipline Kaizen in the best way possible. The cooperating company has recently introduced Kaizen to the organization as part of a transaction toward lean production. The study was conducted using semi-structured interviews along with observations. The problem was approached from a motivational perspective, and a motivational framework has been created for this situation by combining research from the four motivation theories; Attribution theory, Social cognitive theory, Self-determination theory and Expectancy theory. The result from the study shows positive as well as negative aspects of the suggestion system at the factory that should be considered when designing a suggestion system that enhance the effect of Kaizen.

  • 5432.
    Hultgren, Richard
    et al.
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Kullgard, Peter
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Improving configuration management, quality management and development methods in the computer game industry2001Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    There is a lack of maturity in the software game development that results in development companies using their own invented, but not fully completed, procedures. Through a case study this master thesis gives an overview of the game developers maturity in configuration management, quality assurance and development methods in general. It also presents a suggestion on how to address the issues found in the case study.

  • 5433.
    Hultin, Daniel
    et al.
    Blekinge Institute of Technology, School of Management.
    Boström, Henrik
    Blekinge Institute of Technology, School of Management.
    Holmqvist, Jonas
    Blekinge Institute of Technology, School of Management.
    Ett företags kommunikationsstrategi – hur påverkas ledningens externa och interna kommunikationsstrategier vid en börsintroduktion?2008Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Syfte: Syftet med denna uppsats är att studera hur en börsintroduktion påverkar ledningens kommunikationsstrategi i ett företag. Metod: Hela studien utfördes på företaget Waterjet i Ronneby med hjälp av kvalitativa intervjuer med anställda på ledande positioner i organisationen. Slutsatser: Både internt och externt ser vi skillnader jämfört med hur det var före introduktionen. Den största förändringen är i den externa kommunikationen, där företaget nu måste hantera fler ägare, analytiker och investerare. Internt har ledningen utformat nya riktlinjer och policys för hur kommunikationen ska hanteras på bästa vis. Som en del av den interna kommunikationsstrategin har formella möten fått mer betydelse än tidigare, då anställda får diskutera vad börsintroduktionen innebär för deras arbete. Avsikten är att kommunikationen mellan mellanchefer och anställda ska fungera samt att den blir viktigare i samband med att företaget blir publikt, då ryktesspridningar om företaget ska undvikas externt.

  • 5434.
    Hultin, Sebastian
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Leijonhielm, Philip
    Blekinge Institute of Technology, School of Health Science.
    Prostatacancer: Männens upplevelser av livet efter radikal prostatektomi2010Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Bakgrund: Prostatacancer är den vanligaste cancerformen bland män i Sverige. Det finns flera olika behandlingar för sjukdomen varav radikal prostatektomi är den vanligaste. Både sjukdomen och behandlingen medför att männens liv förändras mer eller mindre. Syfte: Syftet med studien var att belysa hur männens liv förändrades efter radikal prostatektomi. Metod: En systematisk litteraturstudie av kvalitativa artiklar utfördes. Syftet i studien besvarades genom att åtta vetenskapliga artiklar valdes ut som sedan analyserades efter Graneheim och Lundmans analysmodell. Resultat: I resultatet framgick att männens liv förändrades efter att de genomgått radikal prostatektomi. De förlorade kontrollen över urinblåsan, sexualiteten förändrades, de levde med ständig oro och ångest samt de hade behov av att bevara relationerna till sina närstående. Slutsatser: Mer vårdvetenskaplig forskning behöver belysa hur radikal prostatektomi förändrar männens liv. Möjligtvis skulle det hjälpa sjuksköterskan i arbetet med att förebygga männens lidande som uppstår i samband med sjukdomen och behandlingen.

  • 5435.
    Hultkrantz, Per
    et al.
    Blekinge Institute of Technology, Department of Business Administration and Social Science.
    Larsson, Gunilla
    Blekinge Institute of Technology, Department of Business Administration and Social Science.
    Self-efficacy, self-esteem och sensitivity to criticism under den sena adolescensen med avseende på betyg, kön och gymnasieprogram.2003Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    En betydelsefull period i många tonåringars liv är gymnasietiden. Avgångsbetygen i gymnasiet spelar en viktig roll för framtida möjligheter att välja yrke eller komma in på universitet eller högskola. Kontexten kan vara avgörande för hur självbilden utvecklas. Syftet med studien var att se om det fanns en skillnad mellan pojkar och flickor i den sena adolescensen angående self-esteem, self-efficacy och sensitivity to criticism. Speciellt intressant var att se eventuella samband mellan dessa psykologiska fenomen och betygen i engelska, matematik och idrott/hälsa samt programvalet. Tre frågeformulär distribuerades ut till 138 tredjeårselever, 53 pojkar och 85 flickor, vid olika gymnasieskolor. Det påvisades högre self-esteem samt lägre sensitivity to criticism hos pojkar än hos flickor. Skillnader mellan könen fanns ej i self-efficacy. Alla betyg korrelerade positivt med self-efficacy, men inga betyg korrelerade med self-esteem trots att det finns vissa kulturellt och socialt betingade skillnader mellan könen. När det gäller self-esteem och sensitivity to criticism visar studien på att könen har samma tro på den egna förmågan till prestation. Diskussionen tar även upp förslag till framtida forskning.

  • 5436.
    Hultstrand, Sebastian
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Software Engineering.
    Olofsson, Robin
    Blekinge Institute of Technology, Faculty of Computing, Department of Software Engineering.
    Git - CLI or GUI: Which is most widely used and why?2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Many of us have encountered the discussion about which interface is better for working with Git, command-line or graphical. This thesis is an attempt to find out which user interface new Git users prefer for Git and what experienced Git users prefer.

    We aimed to find out if there’s anything significant which can be gained from using either of the interfaces in comparison to each other. Lastly we looked at what factors influences git users choice of user interface and how?.

    We have collected data through three interviews and a survey, which yielded approximately 370 responses. Based on our results we’ve found that the command-line interface is the more popular user interface, in general, amongst Git users. We’ve also found that most users stop using graphical user inter- faces, as their primary user interface, as they get more experience with Git. They usually change their primary user interface to a command- line interface or start using both the graphical user interface and the command-line interface together. The results from our study regard- ing why, is presented in this thesis.

  • 5437.
    Hultström, Louise
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Johansson, Ulrika
    Blekinge Institute of Technology, School of Health Science.
    Vårdpersonalens upplevelser av att vårda personer med ätstörningar2008Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Bakgrund: I begreppet ätstörningar innefattas sjukdomarna anorexia nervosa, bulimia nervosa och ätstörningar utan närmare specifikation. Bland vårdpersonal finns en stor brist på kännedom och förståelse för sjukdomen, vilket försvårar vården. Personer med ätstörningar framkallar ofta negativa känslor hos vårdpersonalen, eftersom de ofta möts av starka känslor av fientlighet, ilska och stress. Att vårda dessa personer är således en stor utmaning för vårpersonalen, då de ska skapa en vårdrelation till personerna. Syftet: Syftet med studien var att belysa vårdpersonalens upplevelser av att vårda personer med ätstörningar. Metod: Studien utfördes som en litteraturstudie baserad på sju vetenskapliga artiklar med kvalitativ ansats. Artiklarna har analyserats och inspirerats av Graneheim och Lundmans innehållsanalysmetod. Resultat: Utifrån analysprocessen framkom de fem kategorier som belyser vårdpersonalens upplevelser av att vårda personer med ätstörningar, kunskap, försvårade vården, vårdrelationer, känslor och attityd. Vårdpersonalen upplevde mycket känslor i vården av personer med ätstörningar och förklarar det som en känslomässig resa. Slutsats: Att vårda personer med ätstörningar upplevs ofta av vårdpersonalen som svårt, och negativa känslor som frustration, stress och sorg är vanligt förekommande. Bristfällig kunskap om vård och om beteende hos personer med ätstörningar kan vara en orsak till att vårdpersonalen upplever det negativt att vårda dessa personer. Mer kunskap inom området behövs.

  • 5438.
    Hultén, Linnéa
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Jaxvall, Johan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Den snart färdiga sjuksköterskans kunskaper om trycksårsprevention: En enkätstudie utförd bland sistaterminsstudenter på sjuksköterskeutbildningen2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sammanfattning

    Bakgrund: Säker vård och vårdskador är en viktig kvalitetsindikator för vården och sjuksköterskan med sitt ledningsansvar för omvårdnadsarbetet har en viktig roll här. Med trycksår som en vanligt förekommande vårdskada som har stora möjligheter att förhindras är god kunskap om trycksårsprevalens av väldigt stor vikt för de som inom kort är legitimerade sjuksköterskor.

    Syfte: Att undersöka kunskap kring trycksårsprevention hos sjuksköterskestudenter som går sista terminen på utbildningen.

    Metod: En kvantitativ icke-experimentell deskriptiv design valdes till denna tvärsnittsstudie. En enkät baserad på TAK-enkäten, den svenska översättningen av Beeckman et al.s (2010) validerade instrument användes.

    Resultat: Resultatet presenteras i sex diagram samt en tabell uppdelat i Demografi, Självskattning och Kunskap. Svaren på kunskapsfrågorna visade ett genomsnittsresultat på 11 rätt av 19 frågor (57.9 %). Bristfälliga kunskaper visades särskilt på frågan om vad som orsakar trycksår där endast 27% svarade rätt. Att fukt från urin, avföring eller sårsekretion orsakar trycksår anger majoriteten är ett korrekt påstående, trots att det är felaktigt. Majoriteten av de medverkande skattade sin kunskap inom trycksårsprevention som god eller mycket god.

    Slutsats: Det finns en dissonans mellan självskattningen och den kunskap som studenterna uppvisade. Okunskapen kring vad som orsakar trycksår kan få konsekvenser för ett effektivt preventivt arbete. Bättre möjligheter för att ta in denna kunskap bör ges sjuksköterskestudenter på väg ut i arbetslivet för att kunna möta det behov som finns och stödja dem i att kunna leda omvårdnadsarbetet, ta ansvar för säker vård och lindra det lidande som trycksår ofta innebär. Att undersöka skillnader mellan olika lärosäten och eventuella framgångsfaktorer vid goda resultat är förslag på fortsatt forskning, liksom hur sjuksköterskeprogrammet skulle kunna utvecklas för att främja denna kunskap. 

  • 5439.
    Humanson, Richard
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Industrial Economics.
    Nordeman, Patrik
    Blekinge Institute of Technology, Faculty of Engineering, Department of Industrial Economics.
    Proactive Crisis Management (PCM): Perceptions of crisis-awareness and crisis-readiness in organizations in relation with their actual strategic initiatives against industrial crises caused by human errors.2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Purpose: In a competitive and constituently changing global business environment, it is almost  impossible  for  organizations  to  avoid  crises  of  various  types  and  magnitude.  The objective of this study is to display relationships between perception of crisis awareness, crisis readiness and the organizations` actual crisis management initiatives against major industrial crises. This thesis also aims to clarify if the perception of crisis-awareness and crisis-readiness could be affected by other factors that should be in considerations, which in turn could affect the outcomes of crisis-management initiatives and actions in industrial organizations.

    Methodology:  By  way  of  introduction,  the  problem,  which  is  related  to  the  industrial crises and proactive crisis-management and which also refers to the core topic of the study was formulated and discussed. Research questions about “How the employee’s perception of crisis- awareness  and  crisis-readiness  affects  the  outcomes  of  an  organization's  crisis-management initiatives?”  and “How  top  managements  could  affect  the  employee’s  perception  of  crisis- awareness and crisis-readiness positively toward PCM in their organization?” were identified. The  covering  and  important  data  was  collected  through  scientific  literatures  and  articles  and was presented in the theory part. Collected data and empirical findings from the world’s two largest automaker namely, Volkswagen and Toyota, whom has been involved in scandals and crises related to core research of this paper. Empirical findings has been analyzed and finally the answer to the research questions were proposed.

    Findings: The result of the research indicates that the perception of crisis awareness and crisis  readiness  in  organization  have  a  direct  impact  on  the  organizations  crisis  management initiatives  and  activities  and  also  there  are  elements  like Corporate  Culture,  Personnel Education in Crisis Management and Corporate Communication and also other factors, which would affect the perceptions in organizations.

    Implication:  The  study  suggest  that  by  effective  use  of  elements  presented  here, organizations could influence employees crisis awareness and crisis readiness positively, thus strengthening the organizations crisis management capacities.

  • 5440.
    Humble, Åsa
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Södervall, Lise-Lotte
    Blekinge Institute of Technology, School of Health Science.
    Bemötandet av anhöriga till patienter som vårdas palliativt2005Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Bakgrund: Att vara anhörig till någon som vårdas palliativt innebär ofta en komplicerad livssituation. Inom vården är bemötandet av stor vikt då det är avgörande för den anhöriges upplevelser av omvårdnad, trygghet och delaktighet. Syfte: Studiens syfte var att ur anhörigas perspektiv belysa sjuksköterskans bemötande av anhöriga till patienter som vårdades palliativt på sjukhus, hospice eller i hemmet. Metod: Litteraturstudie där materialet granskades och analyserades efter Graneheim & Lundmans (2003) analysmodell. Resultat: Viktigt för anhöriga var klar och tydlig information, rak kommunikation, delaktighet och en lämplig miljö för patienten. Diskussion: Många anhöriga kände sig hjälplösa, frustrerade och att de tappat kontrollen över situationen. Anhöriga till patienter som vårdas palliativt hade behov av att bli bekräftade, sedda och få sina känslomässiga behov tillfredsställda. Det var viktigt att sjuksköterskan inte enbart såg patienten utan även de anhöriga.

  • 5441.
    Huq, Mohammed Azizul
    Blekinge Institute of Technology, School of Computing.
    Traffic Measurement and Timestamp Accuracy Evaluation of Java ME Traffic Generator on Smartphone2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Research on network traffic measurement is becoming popular because it could find the reason and valuable information regarding the occurrence of timestamp accuracy error. In this thesis the performance of UDP traffic between application level and link level has been investigated on three different Smartphone operating systems. One Java ME traffic generator and sink was developed for this thesis work. Distributed Passive Measurement Infrastructure with Measurement Point was used for the experiment. To get high timestamp accuracy DAG 3.5E card was used which was synchronized with GPS. Through the different tests under different protocol layers, it can be concluded that the Android mobile performs better as Java ME application works like a native application, whereas Symbian and Windows mobile struggles with incompatible implementation for poor JVM support. Time stamping at link level is more accurate and far different from application level. This thesis also investigated the performance evaluation of different JVM for Windows mobile.

  • 5442.
    Husain, Rashid
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Interaction and System Design.
    Kazmi, Syed Muhammad Husnain
    Blekinge Institute of Technology, School of Engineering, Department of Interaction and System Design.
    Comparative Analysis of Static Recovery Schemes for Distributed Computing2008Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    The primary objective of this thesis is to evaluate how grid computing works with their infrastructure. It also provides study to recognize the cases in which dynamic scheduler is preferable, how can the static recovery schemes play an effective role in large distributed system where load balancing is a key element and how can we get optimality in maximum number of crash computers using dynamic or static recovery schemes. This thesis consists of two parts: construction of Golomb and Trapezium modules, and performance comparison of Golomb and Trapezium recovery schemes with dynamic recovery scheme. In the first part we construct two modules that generate the recovery list of n computers, one for Golomb and one for Trapezium. In second part we make three schedulers, two for static recovery scheme and one for dynamic recovery scheme. In static recovery scheme we compare the performance of Golomb and Trapezium recovery scheme then we compare this performance with dynamic recovery scheme by using GridSim.

  • 5443.
    Husain, Syed Farzad
    Blekinge Institute of Technology, School of Engineering.
    Evaluation of Methods for 3D Environment Reconstruction with Respect to Navigation and Manipulation Tasks for Mobile Robots2010Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    The field of 3-D-environment reconstruction has been subject to various research activities in recent years. The applications for mobile robots are manifold. First, for navigation tasks (especially SLAM), the perception of 3-D-obstacles has many advantages over navigation in 2-D-maps, as it is commonly done. Objects that are located hanging above the ground can be recognized and furthermore, the robots gain a lot more information about its operation area what makes localization easier. Second, in the field of tele-operation of robots, a visualization of the environment in three dimensions helps the tele-operator performing tasks. Therefore, a consistent, dynamically updated environment model is crucial. Third, for mobile manipulation in a dynamic environment, an on-line obstacle detection and collision avoidance can be realized, if the environment is known. In recent research activities, various approaches to 3-D-environment reconstruction have evolved. Two of the most promising methods are FastSLAM and 6-D-SLAM. Both are capable of building dense 3D environment maps on-line. The first one uses a Particle Filter applied on extracted features in combination with a robot system model and a measurement model to reconstruct a map. The second one works on 3-D point cloud data and reconstructs an environment using the ICP algorithm. Both of these methods are implemented in GNU C++. Firstly, FastSLAM is implemented. The object-oriented programming technique is used to build up the Particle and Extended Kalman Filters. Secondly, 6-D SLAM is implemented. The concept of inheritance in C++ is used to make the implementation of ICP algorithm as much generic as possible. To test our implementation a mobile robot called Care-O-bot 3 is used. The mobile robot is equipped with a color and a time-of-fight camera. Data sets are taken as the robot moves in different environments and our implementation of FastSLAM and 6-D SLAM is used to reconstruct the maps.

  • 5444.
    Hushi, Zhang
    Blekinge Institute of Technology, School of Computing.
    A Comparison of HTML4 and HTML5 with Respect to Server Response Time and Page Load Time2012Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    HTML5 is a language for structuring and presenting content for the World Wide Web. It is expected to provide better flexibility and interoperability for HTML implementations and offering better user experience than the current HTML4. Previous studies have shown some HTML5 elements are able to provide better accessibility and interaction. In this study, we compare the page load time and server response time of equivalent page, implemented in HTML5 or HTML4, 15 HTML5 elements such as <video>, <audio>and CSS 3.0 are compared with the Flash plug-in, CSS 2.0 and JavaScript in IIS/Apache server. Page load time is defined as the total latency users experience when they open a page, and server response time is the time taken by the first HTTP SNK request that is initiated by device browser to the last FIN packet received from the server while accessing web content.Our results extend previous studies by evaluating new HTML5 elements in Chrome and IE9 browser environment, showing that HTML5 can provide better performance in both client and server side, and the combination of Apache + Chrome is able to maximize the potential of HTML5, which describes a better future for HTML5 development

  • 5445.
    Husic, Maida
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Karlsson, Evelina
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Personers upplevelser av att leva med amyotrofisk lateralskleros: En litteraturstudie baserad på patografier.2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Amyotrofisk lateralskleros (ALS) är en obotlig sjukdom som leder till förlamning genom att de nervceller som styr skelettmuskulaturen bryts ned. De som insjuknar i ALS gör det någon gång mellan 45 och 75 års ålder, majoriteten av dessa går bort inom fem år men vid stor påverkan på andningsmuskulaturen kan döden inträffa tidigare. Eftersom sjukdomen är obotlig ligger fokus på så god omvårdnad som möjligt för dessa personer.

    Syfte: Syftet med studien var att beskriva personers upplevelser av att leva med amyotrofisk lateralskleros.

    Metod: Till litteraturstudien har en kvalitativ ansats valts. Studien är baserad på fem patografier som har analyserats enligt Graneheim och Lundmans tolkning av innehållsanalys.

    Resultat: Resultatet formade fyra kategorier som beskriver personers upplevelser av att leva med ALS. Kategorierna är: att leva i nuet och vara närvarande, att förlora autonomi och bli beroende och att vänta på döden.

    Slutsats: Sjukdomen ALS leder till att livet omvärderas och nya prioriteringar skapas. Trots att personerna upplevde att sjukdomen förde med sig känslor som påverkade livet negativt kunde de hitta lycka, glädje och hopp i livet. De som insjuknar i ALS blir ofrivilligt fråntagna sin kropp vilket leder till existentiella svårigheter samtidigt som stora förändringar sker i livet.

  • 5446.
    HUSSAIN, ARIF
    et al.
    Blekinge Institute of Technology, School of Engineering.
    ASLAM, MUHAMMAD-UMAIR
    Blekinge Institute of Technology, School of Engineering.
    HUDDIN, SALA
    Blekinge Institute of Technology, School of Engineering.
    A COMPARATIVE STUDY OF UMTS/WCDMA AND WIMAX TECHNOLOGIES2009Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    The field of mobile broadband in wireless communication systems is increasingly facing the challenges of the provision of high data rates, improved seamless connectivity and broadband internet services. UMTS/WCDMDA which is a third generation wireless mobile cellular technology has been adopted in most parts of the world and now undergoing a phase of evolution and will be emerged soon as LTE. On the other hand, WiMAX which is also some times called as fourth generation mobile broadband technology is likely to be accepted in many places. With higher data rates for transmission, adaptive modulation and coding, OFDMA based physical layer and a very flexible architecture, WiMAX appears to be suppressing UMTS soon. However, the Long Term Evolution (LTE) of 3G or UMTS is likely to compete the WiMAX both technically and economically. This research provides a comparative interpretation of architecture, salient features, robustness, physical layer, mobility, capacity and coverage aspects of the both UMTS/WCDMA and WiMAX broadband technologies. It also explains the error probabilities in transmission for modulation techniques employed in both technologies. MATLAB simulations are provided in the simulation part of this report to further elaborate the differences in the two technologies in some respects. Simulation results show that the more suitability and effectively of performance for WiMAX. This research helps developing a better understanding for operators and users to make a choice in preferring any of the technologies regarding different features. Based on the study and simulation results of the key features related to capacity and fading of both technologies, we investigate the more suitability of any of the two technologies in terms of better quality and lower error rate in all IP environments.

  • 5447.
    Hussain, Faisal Mateen & Irfan
    Blekinge Institute of Technology, School of Computing.
    Automated Analysis of End User License Agreements2011Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Context Spyware is “computer software that obtains information from a user's computer without the user's knowledge or consent” [25]. Spyware is often embedded in another application and is usually stated in End User License Agreement (EULA) [20]. However it is quite common to accept the EULA without even reading it. Therefore beside the traditional spyware analysis techniques, automated EULA analysis can be helpful for common users in order to identify the spyware [18]. Objectives The techniques of automated EULA analysis do exist however the process of taking a binary application, analyze it, and prepare it in order to extract the EULA has not been studied in existing research. There is a need for such a tool that can extract and analyze the EULA text from an installer binary without executing it. Objectives of this research are to investigate the techniques to unpack the binary file, extract the EULA, analyze it and present the analysis results to the end user. Methods In order to establish basic understanding of the related concepts preliminary study is done. In this study a number of article sources are used, including ACM Digital Library, Compendex, Inspec, IEEE Xplore, and Springer Link. Material has been selected after reading titles and summaries. Prototype of an open source tool is designed and developed. This tool extracts the EULA from executable binary installers, analyzes the extracted text and gives suggestions about legitimate level of the software. Results To evaluate our application we downloaded 150 executables from different web sites, which were already classified as bad or good by [23]. We used our tool to extract EULA text from executables. We were able to extract EULA from 48 percent of selected binary files. Analysis of extracted EULAs was also done to classify the software as good or bad. This analysis assists the user to make a decision to accept or reject the installation of software without reading even a single word of EULA. During the extraction and analysis process there was no significant impact on performance of the host system. Conclusion We conclude that EULA can be extracted from a binary file without executing it. However because of limited time it was not possible to extract EULA from all installer binaries. The rate of EULA extraction can be improved in future research.

  • 5448.
    Hussain, Majid
    Blekinge Institute of Technology, School of Engineering.
    Fuzzy Relations2010Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    One of the most fundamental notions in pure and applied sciences is the concept of a relation. Science has been described as the discovery of relations between objects, states and events. Fuzzy relations generalize the concept of relations in the same manner as fuzzy sets generalize the fundamental idea of sets. This work presents an overview of comparison between classical and fuzzy relations. Some important compositions of fuzzy relations have been described and using these compositions a model for predicting score in cricket is developed. Finally it deals with the restoration and the identification of the causes (diagnosis) through the observed effects (symptoms) on the basis of fuzzy relations.

  • 5449.
    Hussain, Musharrif
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Interaction and System Design.
    Mahmood, Sulman
    Blekinge Institute of Technology, School of Engineering, Department of Interaction and System Design.
    Secure Software and Communication on Handheld Devices2007Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Some applications on mobile handheld devices are involved in exchanging critical information e. g. sending positioning data of heavy-good vehicles as a basis for road toll. This information must not be accessed or modified illegitimately; however, there is the risk that can be accessed or modified by modifying the application or during communication of the handheld device with its counterpart. This thesis report investigates concepts to shelter software from modification and how the communication of these applications running on a handheld device over public mobile network can be made more secure. This work was performed by carefully identifying relevant literature and developing the concept that how a smart card can enhance the security of the software running on it particularly for handheld devices. It also discusses the issues and threats to smart cards. Furthermore it proposes a solution based on the specified scenario. The security of the software comprises on two layers; one layer is for analysis prevention, making it hard to understand the behaviour of the program both at static and dynamic levels. The other layer is responsible for verifying the integrity of the software to ensure that it is not modified. The software is installed on smart card which acts as an extra security layer. The communication relies on the security features of the public mobile network with some enhancement. In order to shelter the communication via public Internet, a border based VPN solution is deployed between the public mobile network and the remote server using the network assisted approach. This thesis will serve as basis for designing a secure communication path for Swedish road toll system.

  • 5450.
    Hussain, Raza
    et al.
    Blekinge Institute of Technology, School of Engineering.
    Sheikh, Sundas
    Blekinge Institute of Technology, School of Engineering.
    Highly Integrated Wideband Doherty Power Amplifier2013Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    The objective of this thesis project was to design a wide band Doherty Power Amplifier (DPA) using bare die transistors. Different techniques had been applied in this thesis to make a DPA wide band while maintaining its efficiency and power. The study of a phase shifter and combiner network was made to find a solution to achieve the desired bandwidth. To determine the best suitable class of amplifier for DPA design, three different classes A, B, AB were considered. The symmetric AB class was used for the main and peak amplifiers. A 15 W GaN HEMT transistor was used for both main and peak amplifiers. The desired range of frequency is from 2 GHz to 3 GHz having 46 dBm peak power with 60% efficiency and 55% efficiency at 6 dBm back off. For the combiner, network Roger’s RO4350, Arlon’s AD1000 and STMicroelectronics’ glass substrate with copper fabricated on it was used. The size of the combiner was 3 mm x 8 mm for AD1000 and 0.7 mm x 0.9 mm for glass substrate. The phase shifter was designed using GaAs technology. The thesis work was validated using ADS Design Tool v2011 and v2009 using design kits for GaAs and glass substrate. Multiple design configurations were simulated, and the design supporting high efficiency and good bandwidth was considered. The band achieved was 2 GHz to 3 GHz with an average efficiency of 58% at 46 dBm peak power and 51% average efficiency at back off power of 40 dBm using the three different substrates. The designed DPA can be used for multiple wireless communication systems such as LTE and WCDMA.

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