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  • 251.
    Eklund, Robert
    Linköpings universitet, Institutionen för teknik och naturvetenskap.
    Linearization of Voltage-Controlled Oscillators in Phase-Locked Loops2005Självständigt arbete på grundnivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    This is a thesis report done as part of the Master of Science in Electronics Design Engineering given at Linköping University, Campus Norrköping. The thesis work is done at Ericsson AB in the spring of 2005. The thesis describes a method of removing variations in the tuning sensitivity of voltage-controlled crystal oscillators due to different manufacturing processes. These variations results in unwanted variations in the modulation bandwidth of the phase-locked loop the oscillator is used in. Through examination of the theory of phase-locked loops it is found that the bandwidth of the loop is dependent on the tuning sensitivity of the oscillator.

    A method of correcting the oscillator-sensitivity by amplifying or attenuating the control-voltage of the oscillator is developed. The size of the correction depends on the difference in oscillator-sensitivity compared to that of an ideal oscillator. This error is measured and the correct correction constant calculated.

    To facilitate the measurements and correction extra circuits are developed and inserted in the loop. The circuits are both analog and digital. The analog circuits are mounted on an extra circuit board and the digital circuits are implemented in VHDL in an external FPGA.

    Tests and theoretical calculations show that the method is valid and able to correct both positive and negative variations in oscillator-sensitivity of up to a factor ±2.5 times. The bandwidth of the loop can be adjusted between 2 to 15 Hz (up to ±8 dB, relative an unmodified loop).

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    FULLTEXT01
  • 252.
    Eliasson, Viktor
    Linköpings universitet, Institutionen för systemteknik, Elektroniksystem. Linköpings universitet, Tekniska högskolan.
    Digital videoregistrering2013Självständigt arbete på grundnivå (högskoleexamen), 10,5 poäng / 16 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This Bachelor thesis examines the possibility of replacing an outdated, analog video recording system to a digital counterpart. It is key that the video and audio signals remain synchronized, generator locked and time stamped. It is up to nine different video sources and a number of audio sources to be recorded and treated in such a manner which enables synchronized playback. The  different video sources do not always follow a universal standard, and differ from format as well as resolution. This thesis aims to compare a number of state of the art commercial of the shelf solutions with proprietary hardware. Great emphasis is placed on giving a functional view over the system features and to evaluate different compression methods. The report also discusses different transmission, storage and playback options. The report culminates in a series of proposed solutions to sub problems which are solved and treated separately, leading to a final proposal from the author. The final draft set how well the system meets pre-set requirements to price.

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    fulltext
  • 253.
    Englund, Madeleine
    Linköpings universitet, Institutionen för systemteknik, Datorteknik. Linköpings universitet, Tekniska högskolan.
    Hybrid Floating-point Units in FPGAs2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Floating point numbers are used in many applications that  would be well suited to a higher parallelism than that offered in a CPU. In  these cases, an FPGA, with its ability to handle multiple calculations  simultaneously, could be the solution. Unfortunately, floating point  operations which are implemented in an FPGA is often resource intensive,  which means that many developers avoid floating point solutions in FPGAs or  using FPGAs for floating point applications.

    Here the potential to get less expensive floating point operations by using ahigher radix for the floating point numbers and using and expand the existingDSP block in the FPGA is investigated. One of the goals is that the FPGAshould be usable for both the users that have floating point in their designsand those who do not. In order to motivate hard floating point blocks in theFPGA, these must not consume too much of the limited resources.

    This work shows that the floating point addition will become smaller withthe use of the higher radix, while the multiplication becomes smaller by usingthe hardware of the DSP block. When both operations are examined at the sametime, it turns out that it is possible to get a reduced area, compared toseparate floating point units, by utilizing both the DSP block and higherradix for the floating point numbers.

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    fulltext
  • 254.
    Engström, Fredrik
    Linköpings universitet, Institutionen för systemteknik.
    VHDL-implementering av GMSK-demodulatorer för DARC i FPGA.2003Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [sv]

    DARC är ett sätt att sända digital information via FM-rundradionätet. Moduleringsmetoden för DARC är GMSK. Målsättningen var att jämföra kostnad/komplexitet och strömförbrukning för olika sätt att demodulera GMSK. Tre icke-koherenta demodulatorer och en koherent demodulator har jämförts. Man vill veta hur stor resursanvändningen var för olika FPGAer. De olika demodulatorerna har beskrivits med VHDL.

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 255.
    Erdemir, Sertac
    et al.
    Linköpings universitet, Institutionen för systemteknik. Linköpings universitet, Tekniska fakulteten.
    Yavuz Oruc, A.
    University of Maryland, MD 20742 USA.
    Noise Analysis of On-Chip Flexing Crossbars With a Geometric Model2016Ingår i: 2016 IEEE INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC COMPATIBILITY (EMC), IEEE , 2016, s. 478-484Konferensbidrag (Refereegranskat)
    Abstract [en]

    Recently, a new family of sparse crossbar switches, called flexing crossbars were introduced in [1] for on-chip networking. This paper describes a geometric approach that incorporates victim-aggressor noise models into the noise analysis and layout of such networks to minimize the crosstalk noise caused by the proximity of crosspoints and wires. It has been shown that flexing crossbars have less crosstalk noise than ordinary crossbars. The approach is sufficiently general enough to be applicable to other switching fabrics in which capacitive wire coupling effects dominate other noise factors.

  • 256.
    Eriksson, Bo
    Linköpings universitet, Institutionen för systemteknik.
    Design of a 32-bit CardBus PC-Card based System Test Platform for the SoCTRix Wireless LAN Transceiver2004Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [en]

    Today, wireless communications is used more then ever before. Wired systems are replaced with wireless versions. New methods and transmission standards are developed and tested. The purpose of this thesis is development of a flexible high-performance System Test Platformfor test of the SoCTRix Wireless LAN Transceiver.

    The result is a Xilinx Virtex-II FPGA based System Test Platform board with CardBus PC Card interface to a computer. The hardware achieved has the following features:

    - 8-layer PCB

    - PCMCIA CardBus PC Card interface, enabling 133 MB/s data throughput

    - 1M Gate Virtex-II FPGA with reprogrammable configuration memory

    - Debugging via LEDs and Logic Analyzer connectors

    - 2x SPI EEPROM

    - 40 MHz system clock

    - Easy connection of two daughter-boards

    Specially designed for wireless transmitter development, can also be used for other computer related highperformance applications.

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    FULLTEXT01
  • 257.
    Eriksson, Christer
    et al.
    Linköpings universitet, Institutionen för systemteknik.
    Lindahl, Erik
    Linköpings universitet, Institutionen för systemteknik.
    Design av FPGA-baserad PCM-till-PWM-modulator för klass D-audioförstärkare2009Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

     

    I detta examensarbete har metoder för design av en FPGA-baserad PCM-till-PWM-modulator för klass D-audioförstärkare testats och utvärderats. Rapporten diskuterar med stöd av matematisk analys och simuleringar interpoleringsmetoder, pulsbreddsmodulering, samplingsprocesser och sigma-delta-modulatorer. Den föreslagna designen bygger på uppsampling, förkompensering, brusformning och pulsbreddsmodulering. Designens prestanda har verifierats genom simulering av modell och implementering i hårdvara.

     

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 258.
    Eriksson, Henrik
    Linköpings universitet, Institutionen för systemteknik.
    Datorstödd implementering med hjälp av Xilinx System Generator2004Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [en]

    The development in electronics increases the demand for good design methods and design tools in the field of electrical engeneering. To improve their design methods Ericsson Microwave Systems AB is interested in using computer tools to create a link between the specification and the implementation of a digital system in a FPGA.

    Xilinx System Generator for DSP is a tool for implementing a model of a digital signalprocessing algorithm in a Xilinx FPGA. To evaluate Xilinx System Generator two testcases has been designed.

    The testcases are selected to represent the FPGA designs made at Ericsson Microwave Systems. The testcases show that Xilinx System Generator can be used to effectivly implement a model made in Simulink in a FPGA from Xilinx. The result of the implementation is comparable to the implementation of VHDL code written by hand.

    The use of tools for implementation of a model in hardware cause change in the design methods used at Ericsson Microwave Systems. The higher level of abstraction introduced by System Generator results in the design decisions made at system level having a higher impact on the final realization.

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    FULLTEXT01
  • 259.
    Eriksson, Jens
    Linköpings universitet, Institutionen för systemteknik.
    Evaluation of Hardware Test Methods for VLSI Systems2005Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [en]

    The increasing complexity and decreasing technology feature sizes of electronic designs has caused the challenge of testing to grow over the last decades. The purpose of this thesis was to evaluate different hardware test methods/approaches based on their applicability in a complex SoC design. Among the aspects that were investigated are test implementation effort, test efficiency and the performance penalties implicated by the test.

    This report starts out by presenting a general introduction to the basics of hardware testing. It then moves on to review available standards and methodologies. In the end one of the more interesting methods is investigated through a case study. The method that was chosen for the case study has been implemented on a DSP, and is rather new and not as prolific as many of the standards discussed in the report. This type of method appears to show promising results when compared to more traditional ones.

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    FULLTEXT01
  • 260.
    Eriksson, Jens
    et al.
    Linköpings universitet, Institutionen för systemteknik.
    Nilsson, Kristian
    Linköpings universitet, Institutionen för systemteknik.
    Implementation of a Serial Communication Interface for a Signal Processor2003Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [en]

    The purpose of this thesis was to implement a serial communication port model for a digital signal processor. It is a behavioral model, developed using VHDL, that is instruction comparisable to the Motorola digital signal processor DSP 56002. It supports five different data transfer modes and provides a programmable baud rate generator.

    This report starts out by giving a description of the external port, port C, the pin control logic and general purpose functionality. Then a more detailed description of the three pin dedicated serial communication interface is presented, the different operating modes and the baud rate generator are described.

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    FULLTEXT01
  • 261.
    Eriksson, Johan
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniksystem. Linköpings universitet, Tekniska högskolan.
    Nilsson, Oscar
    Linköpings universitet, Institutionen för systemteknik, Elektroniksystem. Linköpings universitet, Tekniska högskolan.
    Batterilös strömförsörjning av strömsnål granatelektronik2013Självständigt arbete på grundnivå (kandidatexamen), 10,5 poäng / 16 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Detta examensarbete har utförts vid Saab Dynamics AB(SBD) i Karlskoga med syftet att studera gamla konstruktioner av set-back-generatorer. En set-back-generator (SBG) ska ge momentan energi vid utskjutning av en projektil genom att en magnet rör sig genom en spole. SBG har funnits länge men har bedömts ge för lite energi för att kunna driva elektronik. Men nya typer av magneter har potential att öka energiutbytet väsentligt.

    SBD har ett antal äldre SBG:er och arbetet har varit att utifrån dessa undersöka om det går att utvinna mer energi genom ett utbyte av magnet. Andra parametrar som är viktiga för en SBG:s funktion har också studerats och testats i olika konfigurationer i hopp om ytterligare förbättringar. Förväntade resultat har sedan analyserats och jämförts med mätresultat. Med detta som grund har rekommendationer vid en ny konstruktion av SBG levererats.

    Ladda ner fulltext (pdf)
    SBG
  • 262.
    Eriksson, Oscar
    Linköpings universitet, Institutionen för systemteknik.
    Filterdesign och hårdvarukonstruktion för FMCW-radar2007Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [sv]

    Den här högskoleavhandlingen beskriver designen av ett IF-filter samt hårdvarukonstruktion av en ny 77 GHz FMCW-radar demonstrator. Syftet med demonstratorn är att illustrera hur kisel germanium-, SiGe, teknologi kan användas istället för den mer vedertagna men dyrare gallium arsenik-, GaAs, teknologin. Den gamla radar-prototypen vilken Acreo AB utvecklat är funktionell men behöver konstrueras om för att bättre kunna utvärdera radarprestandan. I avhandlingen presenteras grundläggande radarteori och ekvationer för att underlätta förståelsen av de olika systemblocken. Rapporten beskriver också systemarkitekturen och hur dess funktionalitet kommer att testas. Det omdesignade IF-filtret har simulerats i en PSpice-simulator och ett prototypkort av detta har tillverkats för mätningar. Ett 4-lagers kretskort av hela systemet har tagits fram i Orcad Layout. Slutligen innehåller rapporten förslag på förbättringar till nästa demonstratorversion.

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    FULLTEXT01
  • 263.
    Eriksson, Rikard
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap.
    Badea, Vlad
    Linköpings universitet, Institutionen för teknik och naturvetenskap.
    Indoor navigation with pseudolites (fake GPS sat.)2005Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    This Master Thesis was conducted by Rikard Eriksson and Vlad Badea for their Master of Science degree in Electronics Design Engineering at the University of Linköping (Linköpings Universitet), Sweden. HTC Sweden AB initialized this Thesis and the Thesis contains a pre study of pseudolite based indoor navigation systems, a design of a simple pseudolite and finally some recommendations of applications.

    The pre study starts off with an introduction of the GPS system. This since pseudolite based systems and GPS have many similarities. Different pseudolites based techniques were then investigated and the pre study is wrapped up with a very short briefing on the Hammerhead chip.

    Some of the pseudolite based techniques were worth some more looking into and a pseudolite was therefore designed and simulated. There was unfortunate not enough time to actually build the pseudolite and verify it.

    Some recommendations to HTC Sweden were given in the last chapter of this thesis. The authors of this thesis recommend some interesting techniques and how the future work could proceed.

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    FULLTEXT01
  • 264.
    Erixon, Mats
    Linköpings universitet, Institutionen för teknik och naturvetenskap.
    Design of a Direct-conversion Radio Receiver Front-end in CMOS Technology2002Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [en]

    In this Master's thesis, a direct-conversion receiver front-end has been designed in a 0.18um CMOS technology.

    Direct-conversion receivers (DCR) have obvious advantages over the heterodyne counterpart. Since the intermediate frequency (IF) is zero, the problem of image is circumvented. As a result, no front-end image reject filter is required and the channel selection requires only a low-pass filter, which makes it easy to integrate directly on chip. However, the DCR also suffers from several drawbacks such as extreme sensitivity to DC offsets, 1/f noise, local oscillator (LO) leakage/radiation, front-end nonlinearity and I/Q mismatch. This implies very high demands on the DCR front-end.

    The front-end comprises a low-noise amplifier (LNA) and a mixer. Different LNA and mixer architectures has been studied and from the mentioned inherited problems with direct conversion, one proposal for a solution is a differential source degenerated LNA and a differential harmonic mixer, which has been designed and simulated.

    The LNA has a gain of 12dB, a noise figure of 3.6dB and provides a return loss better than -15dB. The overall noise figure of the signal path is 8dB and the overall IIP3 and IIP2 is -12dBm and 31dBm, respectively.

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 265.
    Esmaeil Zadeh, Iman
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter.
    A Study and Implementation of On-Chip EMC Techniques2010Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    ElectroMagnetic Interferences (EMI) are emerging problems in today's high speed circuits. There are several examples that these interferences affected the circuits and systems. This work tries to reduce the abovementioned problems in synchronous systems by modifying the clock signal such that it produces less interferers.

    In this thesis first EMI and its sources and related definitions are studied in Chap.1 and then a theoretical background is presented in Chap.2, finally Chap.3 and Chap.4 are dedicated to circuit implementation and simulation results, respectively.

    A novel multi-segment clocking scheme is presented in this thesis. An analytical methods for formal verification of advantages of this clocking method is presented in Chap.2. Chap.3 and Chap.4 also are devoted to implementation, simulation and comparison of proposed clocking method versus other methods.

    Since proposed clocking method does not set any constraint on timing (speed of the circuit) and does not impose very high extra power consumption on the circuit, compared to the conventional clocking, this method could be used to reduce interferences in system.

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 266.
    Falk, Daniel
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biosensorer och bioelektronik.
    Patterning of Highly Conductive Conjugated Polymers for Actuator Fabrication2015Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Trilayer polypyrrole microactuators that can operate in air have previously been developed. They consist of two outer layers ofthe electroactive polymer polypyrrole (PPy) and one inner layer of a porous poly(vinylidene flouride) (PVDF) membranecontaining a liquid electrolyte. The two outer layers of PPy are each connected with gold electrodes and separated by the porousPVDF membrane. This microtool is fabricated by bottom-up microfabrication However, porous PVDF layer is not compatible with bottom upmicrofabrication and highly swollen SPE suffers from gold electrode delamination. Hence, in this MSc project/thesis a novelmethod of flexible electrode fabrication with conducting polymers was developed by soft lithography and drop-on-demandprinting. The gold electrodes were replaced by patterned vapor phase polymerized (VPP) poly(3,4-ethylenedioxythiophene) (PEDOT)electrodes due to its high electrical conductivity and versatile process ability. The replacement of the stiff gold electrodes byflexible and stretchable PEDOT allowed high volume change of the material and motions. The PEDOT electrodes werefabricated by patterning the oxidant iron tosylate using microcontact printing and drop-on-demand printing. Moreover, thePVDF membrane has been replaced by a nitrile butadiene rubber/poly(ethylene oxide) semi-interpenetrating polymer network(IPN) to increase ion conductivity and strechability and hence actuator performance.

    Ladda ner fulltext (pdf)
    fulltext
  • 267.
    Fall, Erik
    Linköpings universitet, Institutionen för systemteknik, Datorseende. Linköpings universitet, Tekniska högskolan.
    Compressed Sensing for 3D Laser Radar2014Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Högupplösta 3D-bilder är väldigt intressanta i militära operationer där data kan utnyttjas för klassificering och identifiering av mål. Det är av stort intresse hos Totalförsvarets forskningsinstitut (FOI) att undersöka de senaste teknikerna in- om detta område. Ett stort problem med vanliga 3D-lasersystem är att de saknar hög upplösning för långa mätavstånd. En teknik som har hög avståndsupplös- ning är tidskorrelerande enfotonräknare, som kan räkna enstaka fotoner med extremt bra noggrannhet. Ett sådant system belyser en scen med laserljus och mäter sedan reflektionstiden för enstaka fotoner och kan på så sätt mäta avstånd. Problemet med denna metod är att göra detektion av många pixlar när man bara kan använda en detektor. Att skanna en hel scen med en detektor tar väldigt lång tid och istället handlar det här exjobbet om att göra färre mätningar än antalet pixlar, men ändå återskapa hela 3D-scenen. För att åstadkomma detta används en ny teknik kallad Compressed Sensing (CS). CS utnyttjar att mätdata normalt är komprimerbar och skiljer sig från det traditionella Shannon-Nyquists krav på sampling. Med hjälp av ett Digital Micromirror Device (DMD) kan linjärkombi- nationer av scenen speglas ner på enfotondetektorn och med färre DMD-mönster än antalet pixlar kan hela 3D-scenen återskapas. Med hjälp av en egenutvecklad lasermodell evalueras olika CS rekonstruktionsmetoder och olika scenarier av la- sersystemet. Arbetet visar att basrepresentationen avgör hur många mätningar som behövs och hur olika uppbyggnader av DMD-mönstren påverkar resultatet. CS visar sig möjliggöra att 85 − 95 % färre mätningar än antalet pixlar behövs för att avbilda hela 3D-scener. Total variation minimization visar sig var det bästa valet av rekonstruktionsmetod. 

    Ladda ner fulltext (pdf)
    Compressed Sensing for 3D Laser Radar.pdf
  • 268.
    Fallqvist, Marcus
    Linköpings universitet, Institutionen för systemteknik, Datorseende.
    Automatic Volume Estimation Using Structure-from-Motion Fused with a Cellphone's Inertial Sensors2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I rapporten framgår hur volymen av storskaliga objekt, nämligen grus-och stenhögar,kan bestämmas i utomhusmiljö med hjälp av en mobiltelefons kamerasamt interna sensorer som gyroskop och accelerometer. Projektet är beställt avEscenda Engineering med motivering att ersätta mer komplexa och resurskrävandesystem med ett enkelt handhållet instrument. Implementationen använderbland annat de vanligt förekommande datorseendemetoderna Kanade-Lucas-Tommasi-punktspårning, Struktur-från-rörelse och 3D-karvning tillsammans medenklare sensorfusion. I rapporten framgår att volymestimering är möjligt mennoggrannheten begränsas av sensorkvalitet och en bias.

    Ladda ner fulltext (pdf)
    fulltext
  • 269.
    Fandén, Petter
    Linköpings universitet, Institutionen för teknik och naturvetenskap.
    Evaluation of Xilinx System Generator2001Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [en]

    This Master’s Thesis is an evaluation of the software Xilinx System Generator (XSG) and blockset for Matlab. XSG is a module to simulink developed by Xilinx in order to generate VHDL code directly from functions implemented in Matlab. The evaluation was made at Saab Avionics AB in Järfälla, north of Stockholm.

    In order to investigate the performance of this new module XSG to simulink, a model of a frequency estimator often used in digital radar receivers were implemented in Matlab using XSG. Engineers working at SAAB Avionics implemented the same application directly in VHDL, without using Matlab and the XSG. After generating code the results were synthesised, analysed and compared.

    The frequency estimator basically contains an FFT, a windowing function and a sorting algorithm used to enable analyse of two real signals simultaneously. There were however problems during generation of the VHDL code and the model had to be broken into smaller parts containing only a 16-point FFT. The results of comparison in this report are based on models containing only this 16-point FFT and they show a small advantage for the System Generator according to the resource usage report generated during synthesis.

    Designing models for generation using Xilinx Blockset can create a lot of wiring between components. The reason for this is that the System Generator and Xilinx Blockset today is a new tool, not completely developed. There are many components found in simulink, Matlab that could not be found in Xilinx Blockset, this is however being improved. Another problem is long time for simulation and errors during generation.

    My opinion is that when used for smaller systems and with further development the System Generator can be a useful facility in designing digital electronics.

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 270.
    Fant, Sebastian
    Linköpings universitet, Institutionen för systemteknik.
    A design of a future 10 kW converter2008Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    This master thesis aim to design and evaluate a high power 3-phase DC/AC and AC/AC converter. The purpose is to use it for an electric motor in an aircraft possibly driving electric actuators, a propeller in an UAV or a small vehicle. Factors such as power loss and weight are of importance and will be estimated using known models supplied by various manufacturers of components. Different topologies of semiconductors suitable for this purpose are examined and presented. Extensive resources have been put to properly select the most suitable switching device according to their power loss and weight.

    The need for filters and protective circuits will be estimated according to regulations of common military avionic standards and will be included in the resulting estimation along with simulations to evaluate their need and importance. Snubber circuits will be presented and their specific ability to reduce voltage transients and switching losses will be examined along with some simulations to illustrate their performance. In the final part an estimation of efficiency and weight of higher and lower power models of the same inverter has been made using the same procedure as presented in this paper. Engineering rules have been formed from these estimations to simply be able to calculate the proportions of a future converter of arbitrary rated power.

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  • 271.
    Farid, Amro M.
    et al.
    Masdar Institute of Science & Technology, Masdar City, Abu Dhabi, UAE.
    Ribeiro, Luis
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion. Linköpings universitet, Tekniska högskolan.
    An Axiomatic Design of a Multi-Agent Reconfigurable Manufacturing System Architecture2014Ingår i: Proceedings of ICAD2014 The Eighth International Conference on Axiomatic Design Campus de Caparica – September 24-26, 2014 / [ed] António M. Gonçalves-Coelho, Miguel Cavique and António Mourão, 2014, s. 51-58Konferensbidrag (Refereegranskat)
    Abstract [en]

    In recent years, the fields of reconfigurable manufacturing systems, holonic manufacturing systems, and multi-agent systems have made technological advances to support the ready reconfiguration of automated manufacturing systems.  While these technological advances have demonstrated robust operation and been qualitatively successful in achieving reconfigurability, their ultimate industrial adoption remains limited.  Amongst the barriers to adoption has been the relative absence of formal and quantitative multi-agent system design methodologies based upon reconfigurability measurement.  Hence, it is not clear 1.) the degree to which these designs have achieved their intended level of reconfigurability 2.) which systems are indeed quantitatively more reconfigurable and 3.) how these designs may overcome their design limitations to achieve greater reconfigurability in subsequent design iterations.  To our knowledge, this paper is the first multi-agent system reference architecture for reconfigurable manufacturing systems driven by a quantitative and formal design approach.  It is rooted in an established engineering design methodology called axiomatic design for large flexible engineering systems and draws upon design principles distilled from prior works on reconfigurability measurement.  The resulting architecture is written in terms of the mathematical description used in reconfigurability measurement which straightforwardly allows instantiation for system-specific application.

  • 272.
    Fazli Yeknami, Ali
    Linköpings universitet, Institutionen för systemteknik.
    Design and Evaluation of A Low-Voltage, Process-Variation-Tolerant SRAM Cache in 90nm CMOS Technology2008Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    This thesis presents a novel six-transistor SRAM intended for advanced

    microprocessor cache application. The objectives are to reduce power

    consumption through scaling the supply voltage and to design a SRAM that is fully process-variation-tolerant, utilizing separate read and write access ports as well as exploiting asymmetry. Traditional six-transistor SRAM is designed and its strengths and weaknesses are discussed in detail. Afterwards, a new SRAM technology developed in the division of Electronic Devices, Linköping University is proposed and its capabilities and drawbacks are illustrated deeply. Subsequently, the impact of mismatch and process variation on both standard 6T and proposed asymmetric 6T SRAM cells is investigated. Eventually, the cells are compared regarding the voltage scalability, stability, and tolerability to variations in process parameters. It is shown that the new cell functions in 430mV while maintaining acceptable SNM margin in all process corners. It is also demonstrated that the proposed SRAM is fully process-variation-tolerant.

    Additionally, a dual-V t asymmetric 6T cell is introduced having wide SNM margin comparable with that of conventional 6T cell such that it is capable of functioning in 580mV.

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  • 273.
    Fazli Yeknami, Ali
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Alvandpour, Atila
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    A 0.5-V 250-nW 65-dB SNDR Passive ΔΣ Modulator for Medical Implant Devices2013Ingår i: Proceedings of the IEEE International Symposium on Circuits and Systems (ISCAS), Beijing, China, 19-23 May, 2013, 2013, s. 2010-2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    A  0.5-V  ultra-low-power  second-order  DT  DS  modulator  is  presented  in  this  paper  for  medical  implant  devices.  The  modulator  employs  2nd-order  passive  low-pass filter  and  ultra-low-voltage  building  blocks,  including preamplifier, regenerative comparator, and clock controller, in order  to enable operation near 0.5 V supply. A  low-noise and gain-enhanced  single-stage  preamplifier  is  developed  using  a body-driven technique. Passive filter is gain boosted by power-efficient charge-redistribution amplification  scheme. Designed in  a  65nm CMOS  technology,  the modulator  achieves  65  dB peak SNDR over a 500 Hz signal bandwidth, while it consumes 250 nW  from  a  0.5 V  supply. The modulator  is  functional  at 0.45V and obtains 52 dB SNR, while consuming 200 nW.

  • 274.
    Fazli Yeknami, Ali
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Alvandpour, Atila
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    A 0.7-V 400-nW Fourth-Order Active-Passive Delta-Sigma Modulator with One Active Stage2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    A 0.7 V 400 nW fourth-order active-passive ΔΣ modulator with one active stage is presented in this paper using standard CMOS 65 nm technology. The modulator achieves 84 dB SNR and 80.3 dB SNDR in a signal bandwidth of 500 Hz with a sampling frequency of 256 kHz. The input-feedforward architecture is used to improve the voltage swing before the comparator of the traditional passive modulators, which enables simpler comparator design with no preamplifier as well as cascading three successive power-efficient passive filters. The first active stage is used to reduce the comparator's noise and offset and to minimize the capacitive area. The modulator achieves a high power-efficiency (47 fJ/step) in terms of widely used figure of merit.

  • 275.
    Fazli Yeknami, Ali
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Alvandpour, Atila
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    A 270-mV  ΔΣ Modulator Using Gain-Enhanced, Inverter-Based Amplifier2013Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    An ultra-low-voltage low-power switched-capacitor ΔΣ modulator running at a supply voltage as low as 270 mV is presented for medical implant devices. To reduce the supply voltage and power consumption, an inverter-based amplifier is used in the integrator, whose DC-gain and gain-bandwidth (GBW) are boosted by a simple current-mirror output stage. The full feedforward loop topology offers low integrators internal swing, supporting ultra-low-voltage operation. The entire modulator operates at 270 mV supply only, while the switches are driven by charge pump clock doubler. Designed in 65 nm CMOS and clocked at 256 kHz, the simulation results show that the converter achieves 64.4 dB signal-to-noise-ratio (SNR) and 61 dB signal-to-noise-and-distortionratio (SNDR) in 1 kHz bandwidth while consuming 0.85 "W power.

  • 276.
    Fazli Yeknami, Ali
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Alvandpour, Atila
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    A Variable Bandwidth Amplifier for a Dual-mode Low-Power ΔΣ Modulator in Cardiac Pacemaker System2013Ingår i: Proceedings of the IEEE International Symposium on Circuits and Systems (ISCAS), 2013, s. 1918-1921Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents the design and implementation of a variable bandwidth amplifier intended for ultra-low-power biomedical implants in 65nm CMOS, providing tunable gain-bandwidth in three modes: 0.9 MHz, 1.7 MHz, and 2.3 MHz with consistent 56 dB DC gain. The amplifier consumes 180nW static power in the lowest bandwidth mode, and consumes 315 nW static power in the full bandwidth mode with an 8 pF load from a 0.9-V supply voltage. To illustrate the concept, the presented programmable bandwidth amplifier is applied in a dual-mode ΔΣ modulator aiming for sensing/measuring stage of a cardiac pacemaker.

  • 277.
    Fazli Yeknami, Ali
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Qazi, Fahad
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Alvandpour, Atila
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Low-Power DT ΔΣ Modulators Using SC Passive Filters in 65nm CMOS2014Ingår i: IEEE Transactions on Circuits and Systems Part 1: Regular Papers, ISSN 1549-8328, E-ISSN 1558-0806, Vol. 61, nr 2, s. 358-370Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A comparative design study of ultra-low-power discrete-time ΔΣ modulators (ΔΣ Ms) suited for medical implant devices is presented. Aiming to reduce the analog power consumption, the objective is to investigate the effectiveness of the switched-capacitor passive Þlter. Two design variants of 2nd-order ΔΣ are analyzed and compared to a power-optimized standard active modulator ΔΣΜΑΑ. The first variant ΔΣΜΑP employs an active filer in the 1st stage and a passive filter in the less critical 2nd stage. The second variant (OTA-less ΔΣΜpp) makes use of passive Þlters in both stages. For practical verfication, all three modulators are implemented on a single chip in 65 nm CMOS technology. Designed for 500-Hz signal bandwidth, the ΔΣΜΑΑ, ΔΣΜΑP and ΔΣΜpp achieve 76 dB, 70 dB and 67 dB peak SNDR, while consuming 2.1 μW, 1.27 μW, and 0.92 μW, respectively, from a 0.9 V supply. Furthermore, the ΔΣΜpp can operate at a supply voltage reduced to 0.7 V, achieving a 65 dB SNDR at 430 nW power and 0.296 pJ/step.

  • 278.
    Felekidis, Nikolaos
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Komplexa material och system. Linköpings universitet, Tekniska fakulteten.
    Melianas, Armantas
    Stanford Univ, CA 94305 USA.
    Kemerink, Martijn
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Komplexa material och system. Linköpings universitet, Tekniska fakulteten.
    Automated open-source software for charge transport analysis in single-carrier organic semiconductor diodes2018Ingår i: Organic electronics, ISSN 1566-1199, E-ISSN 1878-5530, Vol. 61, s. 318-328Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Organic electronics is an emerging technology with numerous applications in which the active layer is composed of an organic semiconductor (OSC) or blends of multiple OSC. One of the key performance parameters for such devices is the charge carrier mobility which can be evaluated by different measurement techniques. Here, we review different formalisms for extraction and analysis of hole mobilities from temperature-dependent space-charge limited conductivity (SCLC) measurements for pristine OSC as well as for binary and ternary blends as used in e.g. photovoltaic applications. The model is also applicable to n-type materials. Possible sources of measurement errors, such as the presence of traps and series resistance, are discussed. We show that by a simple method of selecting a proper experimental data range these errors can be avoided. The Murgatroyd-Gill analytical model in combination with the Gaussian Disorder Model is used to extract zero-field hole mobilities as well as estimates of the Gaussian energetic disorder in the HOMO level from experimental data. The resulting mobilities are in excellent agreement with those found from more elaborate fits to a full drift-diffusion model that includes a temperature, field and density dependent charge carrier mobility; the same holds for the Gaussian disorder of pure materials and blends with low fullerene concentration. The zero-field mobilities are also analyzed according to an Arrhenius model that was previously argued to reveal a universal mobility law; for most -but not all- material systems in the present work this framework gave an equally good fit to the experimental data as the other models. An automated fitting freeware, incorporating the different models, is made openly available for download and minimizes error, user input and SCLC data analysis time; e.g. SCLC current-voltage curves at several different temperatures can be globally fitted in a few seconds.

    Publikationen är tillgänglig i fulltext från 2020-06-15 17:03
  • 279.
    Ferdeen, Mats
    Linköpings universitet, Institutionen för systemteknik, Datorteknik.
    Reducing Energy Consumption Through Image Compression2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Energikonsumtionen för att skriva och läsa till off-chip minne är ett känt problem. Inombildbehandlingsområdet struktur från rörelse kan enklare kompressionstekniker användasför att spara energi. En avvägning mellan detekterade features såsom hörn, kanter, etc.och grad av kompression blir då en fråga att utreda. I detta examensarbete har en djuparestudie av denna avvägning utförts. Ett antal mer avancerade kompressionsalgoritmer förbearbetning av stillbilder som tex. JPEG används för jämförelse med ett antal utvaldaenklare kompressionsalgoritmer. De enklare algoritmerna kan delas in i två kategorier:individuell blockvis kompression av vardera bilden och kompression med hänsyn tillsamtliga pixlar i vardera bilden. I studien är bildsekvenserna i gråskala och tillhandahållnafrån en tidigare studie om rullande slutare. Syntetiska data set från ytterligare en studie om’optical flow’ ingår även för att se hur pass tillförlitliga de andra dataseten är.

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  • 280.
    Ferreira, Joao Dias
    et al.
    Kungliga Tekniska Högskolan, Stockholm, Sweden.
    Ribeiro, Luis
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion. Linköpings universitet, Tekniska högskolan.
    Akillioglu, Hakan
    Kungliga Tekniska Högskolan, Stockholm, Sweden.
    Neves, Pedro
    Kungliga Tekniska Högskolan, Stockholm, Sweden.
    Maffei, Antonio
    Kungliga Tekniska Högskolan, Stockholm, Sweden.
    Characterization of an Agile Bio-inspired Shop-Floor2014Ingår i: Proceedings2014 12th IEEE International Conference on Industrial Informatics (INDIN), Porto Alegre, RS, Brazil 27-30 July, 2014, IEEE conference proceedings, 2014, s. 404-410Konferensbidrag (Refereegranskat)
    Abstract [en]

    Sustainability is currently one of the biggest challenges and driver of manufacturing industry. Nevertheless, with the decrease of product life cycles, the consumption of raw materials as well as the obsolescence of production systems increases. In this sense, agile shop-floors that enact companies with the ability to quickly reconfigure their shop-floors by deploying or removing modules are the key for sustainable industrial development. This paper attempts to characterize an innovative approach that relies on bio-inspired concepts as the main control mechanism, in order to foster sustainability by attaining the necessary shop-flooragility. Furthermore an experimental setup is presented and the results are analysed, in order to understand the influence and impact of the main properties that characterize the approach towards the system performance.

  • 281.
    Ferreira, João Dias
    et al.
    Kungliga Tekniska Högskolan, Stockholm, Sweden .
    Ribeiro, Luis
    Universidade Nova de Lisboa, Monte da Caparica, Portugal .
    Onori, Mauro
    Kungliga Tekniska Högskolan, Stockholm, Sweden.
    Barata, Jose
    Universidade Nova de Lisboa, Monte da Caparica, Portugal.
    Challenges and Properties for Bio-inspiration in Manufacturing2014Ingår i: Technological Innovation for Collective Awareness Systems: 5th IFIP WG 5.5/SOCOLNET Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2014, Costa de Caparica, Portugal, April 7-9, 2014. Proceedings / [ed] Luis M. Camarinha-Matos, Nuno S. Barrento, Ricardo Mendonça, Springer Berlin/Heidelberg, 2014, Vol. 423, s. 139-148Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    The increasing market fluctuations and customized products demandhave dramatically changed the focus of industry towards organizationalsustainability and supply chain agility. Such critical changes inevitably have adirect impact on the shop-floor operational requirements. In this sense, anumber of innovative production paradigms emerged, providing the necessarytheoretical background to such systems. Due to similarities between innovativemodular production floors and natural complex systems, modern paradigmstheoretically rely on bio-inspired concepts to attain the characteristics ofbiological systems. Nevertheless, during the implementation phase, bio-inspiredprinciples tend to be left behind in favor of more traditional approaches,resulting in simple distributed systems with considerable limitations regardingscalability, reconfigurable ability and distributed problem resolution.This paper analyzes and presents a brief critical review on how bio-inspiredconcepts are currently being explored in the manufacturing environment, in anattempt to formulate a number of challenges and properties that need to beconsidered in order to implement manufacturing systems that closely follow thebiological principles and consequently present overall characteristics ofcomplex natural systems.

  • 282.
    Florentin, M.
    et al.
    IMB CNM CSIC C Tillers, Spain.
    Cabello, M.
    IMB CNM CSIC C Tillers, Spain.
    Rebollo, J.
    IMB CNM CSIC C Tillers, Spain.
    Montserrat, J.
    IMB CNM CSIC C Tillers, Spain.
    Brosselard, P.
    CALY Technology, France.
    Henry, Anne
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Godignon, P.
    IMB CNM CSIC C Tillers, Spain.
    Al-implanted on-axis 4H-SiC MOSFETs2017Ingår i: Semiconductor Science and Technology, ISSN 0268-1242, E-ISSN 1361-6641, Vol. 32, nr 3, artikel-id 035006Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, the impact of temperature and time stress on gate oxide stability of several multi-implanted and epitaxied 4H-SiC nMOSFET is presented. The oxide layer was processed under a rapid thermal process (RTP) furnace. The variation of the main electrical parameters is shown. We report the high quality and stability of such implanted MOSFETs, and point out the very low roughness effect of the on-axis-cut sample. Particularly, in the best case, effective channel mobility (mu(fe)) overcomes 20 cm(2). V-1. s(-1) at 300 degrees C for a channel length of 12 mu m, which is very encouraging for implantation technology. Starting from 200 degrees C, the apparent increase of the mu(fe) peak of the MOSFET ceases and tends to saturate with further temperature increase. This is an indication of the potential of MOSFETs built on on-axis substrates. Thus, starting from the real case of an implanted MOSFET, the global purpose is to show that the electrical performance of such an on-axis-built device can tend to reach that of the ideal case, i.e. epitaxied MOSFET, and even overcome its electrical limitation, e.g. in terms of threshold voltage stability at high temperature.

  • 283.
    Florén, Johan
    et al.
    Linköpings universitet, Institutionen för systemteknik.
    Lindberg, Daniel
    Linköpings universitet, Institutionen för systemteknik.
    Bluetooth Communication For Remote Controlling Purpose2004Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [en]

    The concept of remote controlling electrical devices is not new; people of today are used to being able to control their household electronic items without making an effort to walk up to the device.

    In this thesis the aim is to use Bluetooth radio signals instead of the traditional infrared light to achieve the remote control functions. As a test application a Sony Compact Disc player is modified in order to be radio controlled with a standard Ericsson T39 mobile phone used as a remote. Since the test application is rather simple without any special requirements the development of a specific radio communication system has not been considered. Instead available pre-manufactured devices were examined. A Bluetooth evaluation kit was purchased and the test project consisted of the goal of linking the evaluation board to the CD player with an AVR microcontroller and getting the whole system to communicate with the mobile phone.

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  • 284.
    Fogdegård, Karl
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap.
    Franzén, Johan
    Linköpings universitet, Institutionen för teknik och naturvetenskap.
    Implementering av Constant Fraction Detection vid avståndsmätning2004Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [en]

    This thesis is performed at Saab Bofors Dynamics in Karlskoga and investigates a technique for ranging with laser pulses. The investigated technique is called Constant Fraction Detection (CFD). Described briefly, the received laser pulse is split into two equal parts, where one part is delayed half the pulse width and inverted. This signal is added to the original pulse. The resulting curve has the shape of a laying S and the detection of the zero level is used to stop the time measurement. The time measurement will be independent of the incoming signal’s amplitude. The CFD technique has the advantage of collecting accurate data for each send pulse, which results in an ability to collect values of measurement with a high frequency. The theses investigates a measurement frequency of 10 kHz that will give an opportunity to implement a scanning function with the possibility to, for example, reproduce a ground structure from a flying object.

    The theses include both digital and analog electronics, which makes it a complex design task. The detector was constructed using analog circuits, from the signal processing of the incoming reflected pulse to the generation of a voltage level as a representation of the distance. The analog part is controlled by digital signals generated by a FPGA, which also performs calculations to convert the voltage level into a distance displayed on a LCD.

    A large part of the work was dedicated to designing a layout and constructing a surface mounted printed circuit board (PCB) and therefor the report treats the whole development process, from technical requirement to construction and verification of a prototype.

    The conclusion states that the CFD technique is a suitable technique for ranging with demands on fast collection of data. The prototype has sufficient accuracy at constant amplitude and was at the time of presentation shown as a prototype for demonstration. The independence of amplitude on the incoming signal was never accomplished and the reason for this is stated in the report. However, further development should solve the problem.

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  • 285.
    Forsgren, Gustav
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Multiple Synchronized Video Streams on IP Network2014Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Video surveillance today can look very different depending on the objective and on the location where it is used. Some applications need a high image resolution and frame rate to carefully analyze the vision of a camera, while other applications could use a poorer resolution and a lower frame rate to achieve it's goals. The communication between a camera and an observer depends much on the distance between them and on the contents. If the observer is far away the information will reach the observer with delay, and if the medium carrying the information is unreliable the observer has to have this in mind. Lost information might not be acceptable for some applications, and some applications might not need it's information instantly.

    In this master thesis, IP network communication for an automatic tolling station has been simulated where several video streams from different sources have to be synchronized. The quality of the images and the frame rate are both very important in these types of surveillance, where simultaneously exposed images are processed together.

    The report includes short descriptions of some networking protocols, and descriptions of two implementations based on the protocols. The implementations were done in C++ using the basic socket API to evaluate the network communication. Two communication methods were used in the implementations, where the idea was to push or to poll images. To simulate the tolling station and create a network with several nodes a number of Raspberry Pis were used to execute the implementations. The report also includes a discussion about how and which video/image compression algorithms the system might benefit of.

    The results of the network communication evaluation shows that the communication should be done using a pushing implementation rather than a polling implementation. A polling method is needed when the transportation medium is unreliable, but the network components were able to handle the amount of simultaneous sent information very well without control logic in the application.

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  • 286.
    Forsgren, Niklas
    Linköpings universitet, Institutionen för systemteknik.
    Sampling Ocsilloscope On-Chip2003Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [en]

    Signal-integrity degradation from such factors as supply and substrate noise and cross talk between interconnects restricts the performance advances in Very Large Scale Integration (VLSI). To avoid this and to keep the signal-integrity, accurate measurements of the on-chip signal must be performed to get an insight in how the physical phenomenon affects the signals.

    High-speed digital signals can be taken off chip, through buffers that add delay. Propagating a signal through buffers restores the signal, which can be good if only information is wanted. But if the waveform is of importance, or if an analog signal should be measured the restoration is unwanted. Analog buffers can be used but they are limited to some hundred MHz. Even if the high-speed signal is taken off chip, the bandwidth of on-chip signals is getting very high, making the use of an external oscilloscope impossible for reliable measurement. Therefore other alternatives must be used.

    In this work, an on-chip measuring circuit is designed, which makes use of the principle of a sampling oscilloscope. Only one sample is taken each period, resulting in an output frequency much lower than the input frequency. A slower signal is easier to take off-chip and it can easily be processed with an ordinary oscilloscope.

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  • 287.
    Fowler, Scott
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    Shahidullah, Ahmed Omar
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    Osman, Mohammed
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    Karlsson, Johan M.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    Yuan, Di
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    Analytical evaluation of extended DRX with additional active cycles for light traffic2015Ingår i: The International Journal of Computer Networks (COMNET), Elsevier, ISSN 1389-1286, Vol. 77, s. 90-102Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Abstract LTE and LTE-Advanced mobile technologies have integrated discontinuous reception (DRX) power saving method to optimize the power consumption at the user equipment (UE). The DRX method was proposed by the 3rd Generation Partnership Project (3GPP), and since then, the traffic behavior has been analyzed in several studies with a standard 3-state DRX model to describe the trade-off between power saving and delay. In this paper, we presented a novel 4-state and 5-state 3GPP LTE DRX mechanisms. The proposed mechanisms were developed by augmenting (an) active state(s) to deep and/or light sleep cycle of standard 3-state DRX for handling a small burst of packets, thereby bypassing the process of returning to the timer-dependent active mode. We have generated analytical models using a semi-Markov process for bursty packet data traffic and evaluated these augmented DRX mechanisms against a standard 3-state DRX method. Overall, the analytical results from varying timing parameters showed that our augmented DRX (both 4-state and 5-state) improved power saving factor (ranging between 1% and 8%) and reduced delay (ranging between 20% and 60%) compared to the standard 3-state DRX. Furthermore, the magnitude of improvement for both delay and power-saving was somewhat greater in 5-state than 4-state.

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  • 288.
    Frankel, Mark S
    et al.
    American Association for the Advancement of Science, U.S.A. .
    Elliott, Roger
    International Council for Science, UK .
    Blume, Martin
    American Physical Society, U.S.A. .
    Bourgois, Jean-Manuel
    Magnard/Vuibert Publishers, France .
    Hugenholtz, Bernt
    University of Amsterdam, The Netherlands .
    Lindquist, Mats G.
    Lund University Library, Sweden .
    Morris, Sally
    ciation of Learned & Professional Society Publishers, U.K. .
    Sandewall, Erik
    Linköpings universitet, Institutionen för datavetenskap, CASL - Cognitive Autonomous Systems Laboratory. Linköpings universitet, Tekniska högskolan.
    Defining and Certifying Electronic Publication in Science2000Ingår i: Learned Publishing, ISSN 0953-1513, E-ISSN 1741-4857, Vol. 13, nr 4, s. 251-258Artikel i tidskrift (Refereegranskat)
  • 289.
    Fransson, Daniel
    Linköpings universitet, Institutionen för systemteknik.
    Lågoffsetkomparator2002Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [sv]

    För att kunna detektera små signalnivåer med en komparator krävs att den har en lägre total spänningsoffset än den signalnivå den skall detektera. I den totala offseten ingår dels den rena spänningsoffseten i komparatorn och dels den spänningsoffset som kommer att skapas när offsetströmmar på komparatorns ingångar går igenom den last som finns på ingången. Målet med den komparator som utvecklats har varit att den skall ha en total spänningsoffset på maximalt 500 uV. Inga direkta krav såsom att den skall vara snabb och att den skall kunna arbeta inom ett stort frekvensområde finns. För att få den flexibilitet som behövs är komparatorn konstruerad i en så kallad full custom teknik. När missanpassningen är som mest ogynnsam hamnar den totala spänningsoffseten på 209.24 uV vilket ligger inom målet med god marginal.

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 290.
    Franzen, Johan
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska högskolan.
    Schweidenbach, Simon
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska högskolan.
    Further development of work samples for pump control2013Självständigt arbete på grundnivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    IKG Östra Sverige AB var i behov av ett arbetsprov som nyanställda ska genom gå när de söker anställning hos IKG. Anställningsprovet togs fram för att testa de nyanställdas kunskaper i elteknik och styrteknik. Anställningsprovet gick ut på att nivåreglera en tank utifrån en funktionslista.

    Uppgiften med detta examensarbete är att vidareutveckla ett anställningsprov så att anställningsprovet kan sätta i bruk. I vidareutvecklingen ingår det att ta fram underlag till arbetsprovet, underlaget som ska tas fram består av arbetsritningar, apparatlista, kabellista och I/O-lista.

    Till IKG Östra Sverige AB togs det fram flera förslag på komponenter och utifrån komponenterna som valdes gjordes det arbetsritningar och en apparatlista. Arbetsritningarna utfördes i en äldre version av Elmaster design som är ett elritningsprogram. Kabelmärkning gjordes för att kunna följa upp ritningarna och en kabellista gjordes för att underlätta installationen. En I/O-lista arbetades fram för att få reda på hur inoch utgångar påverkade styrprocessen i tanken.

    Ladda ner fulltext (pdf)
    fulltext
  • 291.
    Fredriksson, Axel
    Linköpings universitet, Institutionen för systemteknik, Elektroniska Kretsar och System.
    Konstruktion av en solcellssimulator2017Självständigt arbete på grundnivå (kandidatexamen), 10,5 poäng / 16 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I denna rapport så genomförs en konstruktion av en solpanelkrets. Denna krets kommer att användas i utbildningssyfte så en användare kan skaffa sig en förståelse för hur en solpanel fungerar. Solpanelkretsen seriekopplas för att efterlikna riktiga solpaneler. På kretsen så kan en användare ställa in önskad skuggning som motsvarar olika väderförhållanden som en riktig solpanel kan befinna sig i, samt se hur skugga påverkar en solpanel och seriekopplade solpaneler. Kretsen styrs sedan med någon heter MPPT för att utvinna maximal effekt under alla väderförhållanden som en solpanel kan befinna sig i.

    I rapporten så presenteras först väsentlig solteori för att ge upphov till en ökad förståelse för hur solpaneler fungerar. Rapporten bygger mycket på att jämföra simulerade grafer från kretssimuleringsprogrammet Multisim med den fysiska byggda kretsen. Grafer från en solpanel och seriekopplade solpaneler med och utan bypass dioder presenteras. Mätningar från MPPT-styrningen genomförs för att visa vilken maximal effekt som utvanns från den fysiska byggda kretsen. Alla mätningar som genomförts finns i ett resultatkapitel och till sist så diskuteras resultatet och förslag på vidareutvecklingar.

    Ladda ner fulltext (pdf)
    Konstruktion av en solcellssimulator
  • 292. Beställ onlineKöp publikationen >>
    Fredriksson, Henrik
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Improvement Potential and Equalization Circuit Solutions for Multi-drop DRAM Memory Buses2008Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Digital computers have changed human society in a profound way over the last 50 years. Key properties that contribute to the success of the computer are flexible programmability and fast access to large amounts of data and instructions. Effective access to algorithms and data is a fundamental property that limits the capabilities of computer systems. For PC computers, the main memory consists of dynamic random access memory (DRAM). Communication between memory and processor has traditionally been performed over a multi-drop bus.

    Signal frequencies on these buses have gradually increased in order to keep up with the progress in integrated circuit data processing capabilities. Increased signal frequencies have exposed the inherent signal degradation effects of a multidrop bus structure. As of today, the main approach to tackle these effects has been to reduce the number of endpoints of the bus structure. Though improvements in DRAM memory technology have increased the available memory size at each endpoint, the increase has not been able to fully fulfill the demand for larger system memory capacity. Different bus structural changes have been used to overcome this problem. All are different compromises between access latency, data transmission capacity, memory capacity, and implementation costs.

    In this thesis we focus on using the signal processing capabilities of a modern integrated circuit technology as an alternative to bus structural changes. This has the potential to give low latency, high memory capacity, and relatively high data transmission capacity at an additional cost limited to integrated circuit blocks. We first use information theory to estimate the unexplored potential of existing multi-drop bus structures. Hereby showing that reduction of the number of endpoints for multi-drop buses, is by no means based on the fundamental limit of the data transmission capacity of the bus structure. Two test-chips have been designed and fabricated to experimentally demonstrate the feasibility of several Gb/s data-rates over multidrop buses, with limited cost overhead and no latency penalty. The test-chips implement decision feedback equalization, adopted for high speed multi-drop use. The equalizers feature digital filter implementations which, in combination with high speed DACs, enable the use of long digital filters for high speed decision feedback equalization. Blind adaptation has also been implemented to demonstrate extraction of channel characteristics during data transmission. The use of single sided equalization has been proposed in order to limit the need for equalization implementation to the host side of a DRAM memory bus. Furthermore, we propose to utilize the reciprocal properties of the communication channel to ensure that single sided equalization can be performed without any channel characterization hardware on the memory chips. Finally, issues related to evaluation of high-speed channels are addressed and the on-chip structures used for channel evaluation in this project are presented.

    Ladda ner fulltext (pdf)
    FULLTEXT01
    Ladda ner (pdf)
    COVER01
  • 293.
    Frewin, Christopher L.
    et al.
    University of Texas Dallas, TX 75080 USA.
    Bernardin, Evans
    University of S Florida, FL 33612 USA.
    Deku, Felix
    University of Texas Dallas, TX 75080 USA.
    Everly, Richard
    USF, FL 33617 USA.
    Ul-Hassan, Jawad
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Halvledarmaterial. Linköpings universitet, Tekniska fakulteten.
    Pancrazio, Joseph J.
    University of Texas Dallas, TX 75080 USA.
    Saddow, Stephen E.
    University of S Florida, FL 33612 USA.
    Silicon Carbide As a Robust Neural Interface (Invited)2016Ingår i: GALLIUM NITRIDE AND SILICON CARBIDE POWER TECHNOLOGIES 6, ELECTROCHEMICAL SOC INC , 2016, Vol. 75, nr 12, s. 39-45Konferensbidrag (Refereegranskat)
    Abstract [en]

    The intracortical neural interface (INI) could be a key component of brain machine interfaces (BMI), devices which offer the possibility of restored physiological neurological functionality for patients suffering from severe trauma to the central or peripheral nervous system. Unfortunately the main components of the INI, microelectrodes, have not shown appropriate long-term reliability due to multiple biological, material, and mechanical issues. Silicon carbide (SiC) is a semiconductor that is completely chemically inert within the physiological environment and can be micromachined using the same methods as with Si microdevices. We are proposing that a SiC material system may provide the improved longevity and reliability for INI devices. The design, fabrication, and preliminary electrical and electrochemical testing of an all-SiC prototype microelectrode array based on 4H-SiC, with an amorphous silicon carbide (a-SiC) insulator, is described. The fabrication of the planar microelectrode was performed utilizing a series of conventional micromachining steps. Preliminary electrochemical data are presented which show that these prototype electrodes display suitable performance.

  • 294.
    Fritzin, Jonas
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Alvandpour, Atila
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Low-Voltage High-Efficiency Class-E Power Amplifiers in 130nm CMOS for Short-Range Wireless Communications2009Ingår i: in Swedish System on Chip Conference, SSoCC, Arild, May 4-5, Lunds universitet, 2009Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    This paper presents the design of two lowvoltagedifferential class-E power amplifiers (PA) for DECTand Bluetooth fabricated in 130nm CMOS. In order tominimize the on-chip losses and to achieve a high efficiency atlow supply voltages, the PAs do not use on-chip outputmatching networks. At 1.5V supply voltage, the DECT PAdelivers +26.4dBm of output power with a drain efficiency(DE) and power-added efficiency (PAE) of 41% and 30%,respectively. The Bluetooth PA delivers +22.7dBm at 1V witha DE and PAE of 48% and 36%, respectively. A continuouslong-term test of 100 hours proves the reliability of thedesign.

  • 295.
    Fritzin, Jonas
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Mesgarzadeh, Behzad
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Alvandpour, Atila
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    A Class-D Stage with Third Harmonic Suppression and DLL-Based Phase Generation2012Konferensbidrag (Refereegranskat)
  • 296.
    Fritzin, Jonas
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Svensson, Christer
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Alvandpour, Atila
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    A +32dBm 1.85GHz Class-D Outphasing RF PA in 130nm CMOS for WCDMA/LTE2011Ingår i: Proceedings of the IEEE European Solid-State Circuits Conference (ESSCIRC), IEEE , 2011, s. 127-130Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents a Class-D outphasing RF Power Amplifier (PA) which can operate at a 5.5V supply and deliver +32dBm at 1.85 GHz in a standard 130nm CMOS technology. The PA utilizes four on-chip transformers to combine the outputs of eight Class-D stages. The Class-D stages utilize a cascode configuration, driven by an AC-coupled low-voltage driver, to allow a 5.5 V supply in the 1.2/2.5 V 130nm process without excessive device voltage stress. Spectral and modulation requirements were met when a WCDMA and an LTE signal (20 MHz, 16-QAM) were applied to the outphasing PA. At +28.0 dBm channel power for the WCDMA signal, the measured ACLR at 5 MHz and 10 MHz offset were −38.7 dBc and −47.0 dBc, respectively. At +24.9 dBm channel power for the LTE signal, the measured ACLR at 20MHz offset was −34.9 dBc. To the authors' best knowledge, the PA presented in this work has a 3.9 dB higher output power compared to published CMOS Class-D RF PAs.

  • 297.
    Fritzson, Peter
    Linköpings universitet, Institutionen för datavetenskap, Programvara och system. Linköpings universitet, Tekniska högskolan.
    Principles of object-oriented modeling and simulation with Modelica 3.3: a cyber-physical approach2015 (uppl. 2)Bok (Övrigt vetenskapligt)
    Abstract [en]

    The second edition features improvements and updates of the Modelica language including synchronous clocked constructs, examines basic concepts of cyber-physical, equation-based, object-oriented system modeling and simulation. Prof. Fritzson introduces the Modelica class concept and its use in graphical and textual modeling with several hundred examples from many application areas and explores modeling methodology for continuous, discrete, and hybrid systems; and more.

    This text is aimed at System Modeling and Simulation engineers, control engineers, mechanical engineers, those working with CAD (Computer Aided Design), virtual reality, biochemistry, embedded systems, and data communication.

    Fritzson covers the Modelica language in impressive depth from the basic concepts such as cyber-physical, equation-base, object-oriented, system, model, and simulation, while also incorporating over a hundred exercises and their solutions for a tutorial, easy-to-read experience.

    • The only book with complete Modelica 3.3 coverage
    • Over one hundred exercises and solutions
    • Examines basic concepts such as cyber-physical, equation-based, object-oriented, system, model, and simulation

    Ladda ner (jpg)
    presentationsbild
  • 298.
    Frykskog, David
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Jonsson, Hjalmar
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Construction of RF-link budget template for transceiver modelling2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This master thesis report details the process of developing a simulation platform for radio transceivers with a focus on analog receiver front end system design. The platform was implemented in the National Instruments VSS environment for the company Ericsson AB.

    Ladda ner fulltext (pdf)
    Construction of RF-link budget template for transceiver modelling
  • 299. Beställ onlineKöp publikationen >>
    Gabrielsson, Erik O.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska högskolan.
    Monopolar and Bipolar Membranes in Organic Bioelectronic Devices2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In the 1970s it was discovered that organic polymers, a class of materials otherwise best know as insulating plastics, could be made electronically conductive. As an alternative to silicon semiconductors, organic polymers offer many novel features, characteristics, and opportunities, such as producing electronics at low costs using printing techniques, using organic chemistry to tune optical and electronic properties, and mechanical flexibility. The conducting organic polymers have been used in a vast array of devices, exemplified by organic transistors, light-emitting diodes, and solar cells. Due to their softness, biocompatibility, and combined electronic and ionic transport, organic electronic materials are also well suited as the active material in bioelectronic applications, a scientific and engineering area in which electronics interface with biology. The coupling of ions and electrons is especially interesting, as ions serve as signal carriers in all living organisms, thus offering a direct translation of electronic and ionic signals. To further enable complex control of ionic fluxes, organic electronic materials can be integrated with various ionic components, such as ion-conducting diodes and transistors.

    This thesis reports a background to the field of organic bioelectronic and ionic devices, and also presents the integration of ionic functions into organic bioelectronic devices. First, an electrophoretic drug delivery device is presented, capable of delivering ions at high spatiotemporal resolution. The device, called the organic electronic ion pump, is used to electronically control amyloid-like aggregation kinetics and morphology of peptides, and offers an interesting method for studying amyloids in vitro. Second, various ion-conducting diodes based on bipolar membranes are described. These diodes show high rectification ratio, i.e. conduct ions better for positive than for negative applied voltage. Simple ion diode based circuits, such as an AND gate and a full-wave rectifier, are also reported. The AND gate is intended as an addressable pH pixel to regulate for example amyloid aggregation, while the full-wave rectifier decouples the electrochemical capacity of an electrode from the amount of ionic charge it can generate. Third, an ion transistor, also based on bipolar membranes, is presented. This transistor can amplify and control ionic currents, and is suitable for building complex ionic logic circuits. Together, these results provide a basic toolbox of ionic components that is suitable for building more complex and/or implantable organic bioelectronic devices.

    Delarbeten
    1. Spatially Controlled Amyloid Reactions Using Organic Electronics
    Öppna denna publikation i ny flik eller fönster >>Spatially Controlled Amyloid Reactions Using Organic Electronics
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    2010 (Engelska)Ingår i: SMALL, ISSN 1613-6810, Vol. 6, nr 19, s. 2153-2161Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Abnormal protein aggregates, so called amyloid fibrils, are mainly known as pathological hallmarks of a wide range of diseases, but in addition these robust well-ordered self-assembled natural nanostructures can also be utilized for creating distinct nanomaterials for bioelectronic devices. However, current methods for producing amyloid fibrils in vitro offer no spatial control. Herein, we demonstrate a new way to produce and spatially control the assembly of amyloid-like structures using an organic electronic ion pump (OEIP) to pump distinct cations to a reservoir containing a negatively charged polypeptide. The morphology and kinetics of the created proteinaceous nanomaterials depends on the ion and current used, which we leveraged to create layers incorporating different conjugated thiophene derivatives, one fluorescent (p-FTAA) and one conducting (PEDOT-S). We anticipate that this new application for the OEIP will be useful for both biological studies of amyloid assembly and fibrillogenesis as well as for creating new bioelectronic nanomaterials and devices.

    Ort, förlag, år, upplaga, sidor
    John Wiley and Sons, Ltd, 2010
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-61175 (URN)10.1002/smll.201001157 (DOI)000283274100013 ()
    Tillgänglig från: 2010-11-08 Skapad: 2010-11-05 Senast uppdaterad: 2018-04-25
    2. Controlled Microscopic Formation of Amyloid-Like Aβ Aggregates Using an Organic Electronic Device
    Öppna denna publikation i ny flik eller fönster >>Controlled Microscopic Formation of Amyloid-Like Aβ Aggregates Using an Organic Electronic Device
    Visa övriga...
    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Alzheimer’s disease (AD), primarily associated with formation of fibrillar amyloid-beta peptide (Aβ) aggregates in the brain, is one of the most common old-age diseases. It is therefore crucial with an elevated scientific interest in Aβ, and its fundamental properties in a wide sense, to develop efficient methods for early detection and to combat AD. For the development of new techniques, both for AD detection and prevention, researchers are dependent on either tissue samples from deceased patients, animal models or in vitro systems. In vitro systems, such as producing protein aggregates of the Aβ-peptide in a test tube by incubation under denaturing conditions, offers us a simple but rather blunt tool for evaluating aggregation inhibition caused by compounds or to investigate new detection methods. We recently introduced the organic electronic ion pump (OEIP) as a method for creating amyloid-like aggregates at high spatiotemporal control as compared to the resulting aggregates manufactured using regular test tube-conditions. Combined with a fluorescent probe that is specific for the fibrillar aggregated form of misfolded peptides commonly seen in AD, this allowed us to control and to monitor the aggregation of a model peptide system in a highly confined space.

    To further elaborate the functionality of the OEIP together with amyloid-specific probes, we here present experiments demonstrating electronically controlled micron sized formation of Aβ-aggregates with morphologies ranging from fine fibers, to bundles of fibers, and thick mesh-like fiber structures. We foresee that the methodology can be implemented in multi array systems that can be utilized for studies of protein aggregation in confined spaces or together with cultured cells, as well as for the development of screening platforms for assessment of molecules influencing the Aβ-aggregation process.

    Nationell ämneskategori
    Polymerteknologi Annan elektroteknik och elektronik Biokemi och molekylärbiologi
    Identifikatorer
    urn:nbn:se:liu:diva-110401 (URN)
    Tillgänglig från: 2014-09-10 Skapad: 2014-09-10 Senast uppdaterad: 2018-04-25Bibliografiskt granskad
    3. Ion diode logics for pH control
    Öppna denna publikation i ny flik eller fönster >>Ion diode logics for pH control
    2012 (Engelska)Ingår i: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 12, nr 14, s. 2507-2513Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Electronic control over the generation, transport, and delivery of ions is useful in order to regulate reactions, functions, and processes in various chemical and biological systems. Different kinds of ion diodes and transistors that exhibit non-linear current versus voltage characteristics have been explored to generate chemical gradients and signals. Bipolar membranes (BMs) exhibit both ion current rectification and water splitting and are thus suitable as ion diodes for the regulation of pH. To date, fast switching ion diodes have been difficult to realize due to accumulation of ions inside the device structure at forward bias – charges that take a long time to deplete at reverse bias. Water splitting occurs at elevated reverse voltage bias and is a feature that renders high ion current rectification impossible. This makes integration of ion diodes in circuits difficult. Here, we report three different designs of micro-fabricated ion bipolar membrane diodes (IBMDs). The first two designs consist of single BM configurations, and are capable of either splitting water or providing high current rectification. In the third design, water-splitting BMs and a highly-rectifying BM are connected in series, thus suppressing accumulation of ions. The resulting IBMD shows less hysteresis, faster off-switching, and also a high ion current rectification ratio as compared to the single BM devices. Further, the IBMD was integrated in a diode-based AND gate, which is capable of controlling delivery of hydroxide ions into a receiving reservoir.

    Ort, förlag, år, upplaga, sidor
    Cambridge, UK: Royal Society of Chemistry, 2012
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-78002 (URN)10.1039/C2LC40093F (DOI)000305532600009 ()
    Tillgänglig från: 2012-06-04 Skapad: 2012-06-04 Senast uppdaterad: 2017-12-07
    4. Polyphosphonium-based bipolar membranes for rectification of ionic currents
    Öppna denna publikation i ny flik eller fönster >>Polyphosphonium-based bipolar membranes for rectification of ionic currents
    2013 (Engelska)Ingår i: Biomicrofluidics, ISSN 1932-1058, E-ISSN 1932-1058, Vol. 7, nr 6, s. 064117-Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Bipolar membranes (BMs) have interesting applications within the field of bioelectronics, as they may be used to create non-linear ionic components (e. g., ion diodes and transistors), thereby extending the functionality of, otherwise linear, electrophoretic drug delivery devices. However, BM based diodes suffer from a number of limitations, such as narrow voltage operation range and/or high hysteresis. In this work, we circumvent these problems by using a novel polyphosphonium-based BM, which is shown to exhibit improved diode characteristics. We believe that this new type of BM diode will be useful for creating complex addressable ionic circuits for delivery of charged biomolecules.

    Ort, förlag, år, upplaga, sidor
    American Institute of Physics (AIP), 2013
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-103883 (URN)10.1063/1.4850795 (DOI)000329292200020 ()
    Tillgänglig från: 2014-01-30 Skapad: 2014-01-30 Senast uppdaterad: 2017-12-06
    5. A Four-Diode Full-Wave Ionic Current Rectifier Based on Bipolar Membranes: Overcoming the Limit of Electrode Capacity
    Öppna denna publikation i ny flik eller fönster >>A Four-Diode Full-Wave Ionic Current Rectifier Based on Bipolar Membranes: Overcoming the Limit of Electrode Capacity
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    2014 (Engelska)Ingår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 26, nr 30, s. 5143-5147Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Full-wave rectification of ionic currents is obtained by constructing the typical four-diode bridge out of ion conducting bipolar membranes. Together with conjugated polymer electrodes addressed with alternating current, the bridge allows for generation of a controlled ionic direct current for extended periods of time without the production of toxic species or gas typically arising from electrode side-reactions.

    Ort, förlag, år, upplaga, sidor
    Wiley-VCH Verlagsgesellschaft, 2014
    Nyckelord
    bioelectronics, ionics, ion transport, bipolar membranes, conjugated polymer electrodes
    Nationell ämneskategori
    Annan elektroteknik och elektronik Polymerteknologi
    Identifikatorer
    urn:nbn:se:liu:diva-110403 (URN)10.1002/adma.201401258 (DOI)000340546300010 ()24863171 (PubMedID)
    Forskningsfinansiär
    Vinnova, 2010–00507EU, FP7, Sjunde ramprogrammet, iONE-FP7Vetenskapsrådet, 621–2011–3517EU, FP7, Sjunde ramprogrammet, OrgBIO
    Tillgänglig från: 2014-09-10 Skapad: 2014-09-10 Senast uppdaterad: 2017-12-05Bibliografiskt granskad
    6. Polyphosphonium-Based Ion Bipolar Junction Transistors
    Öppna denna publikation i ny flik eller fönster >>Polyphosphonium-Based Ion Bipolar Junction Transistors
    2014 (Engelska)Ingår i: Biomicrofluidics, ISSN 1932-1058, E-ISSN 1932-1058, Vol. 8, nr 6, s. 064116-Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Advancements in the field of electronics during the past few decades have inspired the use of transistors in a diversity of research fields, including biology and medicine. However, signals in living organisms are not only carried by electrons, but also through fluxes of ions and biomolecules. Thus, in order to implement the transistor functionality to control biological signals, devices that can modulate currents of ions and biomolecules, i.e. ionic transistors and diodes, are needed. One successful approach for modulation of ionic currents is to use oppositely charged ion-selective membranes to form so called ion bipolar junction transistors (IBJTs). Unfortunately, overall IBJT device performance has been hindered due to the typical low mobility of ions, large geometries of the ion bipolar junction materials, and the possibility of electric field enhanced (EFE) water dissociation in the junction. Here, we introduce a novel polyphosphonium-based anion-selective material into npn-type IBJTs. The new material does not show EFE water dissociation and therefore allows for a reduction of junction length down to 2 μm, which significantly improves the switching performance of the ion transistor to 2 s. The presented improvement in speed as well the simplified design will be useful for future development of advanced iontronic circuits employing IBJTs, for example addressable drug-delivery devices.

    Nyckelord
    WATER DISSOCIATION; NANOFLUIDIC DIODE; MEMBRANES; CIRCUITS
    Nationell ämneskategori
    Annan elektroteknik och elektronik
    Identifikatorer
    urn:nbn:se:liu:diva-110400 (URN)10.1063/1.4902909 (DOI)000347160400018 ()
    Anmärkning

    This research was financed by VINNOVA (OBOE Miljo and AFM), the Swedish Research Council, and the Onnesjo foundation.

    Tillgänglig från: 2014-09-10 Skapad: 2014-09-10 Senast uppdaterad: 2017-12-05Bibliografiskt granskad
    Ladda ner fulltext (pdf)
    Monopolar and Bipolar Membranes in Organic Bioelectronic Devices
    Ladda ner (pdf)
    omslag
  • 300.
    Gabrielsson, Erik O.
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska högskolan.
    Armgarth, Astrid
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska högskolan.
    Hammarström, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska högskolan.
    Nilsson, K. Peter N.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska högskolan.
    Berggren, Magnus
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska högskolan.
    Controlled Microscopic Formation of Amyloid-Like Aβ Aggregates Using an Organic Electronic DeviceManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Alzheimer’s disease (AD), primarily associated with formation of fibrillar amyloid-beta peptide (Aβ) aggregates in the brain, is one of the most common old-age diseases. It is therefore crucial with an elevated scientific interest in Aβ, and its fundamental properties in a wide sense, to develop efficient methods for early detection and to combat AD. For the development of new techniques, both for AD detection and prevention, researchers are dependent on either tissue samples from deceased patients, animal models or in vitro systems. In vitro systems, such as producing protein aggregates of the Aβ-peptide in a test tube by incubation under denaturing conditions, offers us a simple but rather blunt tool for evaluating aggregation inhibition caused by compounds or to investigate new detection methods. We recently introduced the organic electronic ion pump (OEIP) as a method for creating amyloid-like aggregates at high spatiotemporal control as compared to the resulting aggregates manufactured using regular test tube-conditions. Combined with a fluorescent probe that is specific for the fibrillar aggregated form of misfolded peptides commonly seen in AD, this allowed us to control and to monitor the aggregation of a model peptide system in a highly confined space.

    To further elaborate the functionality of the OEIP together with amyloid-specific probes, we here present experiments demonstrating electronically controlled micron sized formation of Aβ-aggregates with morphologies ranging from fine fibers, to bundles of fibers, and thick mesh-like fiber structures. We foresee that the methodology can be implemented in multi array systems that can be utilized for studies of protein aggregation in confined spaces or together with cultured cells, as well as for the development of screening platforms for assessment of molecules influencing the Aβ-aggregation process.

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