I detta examensarbete har ett system utvecklats som samplar och digitaliserar en högfrekvent analog Signal och lagrar de samplade värdena i ett minne. Systemet genererar en analog utSignal genom att antingen direkt omvandla de samplade värdena eller genom att använda sampels lagrade i minnet som källa för omvandlingen. Det går då att använda systemet både som en passiv länk eller som en Signalkälla.En triggfunktion har implementerats för att på ett effektivt sätt ge möjlighet att fylla minnet med för användaren intressanta delar av en Signal. Arbetet går även ut på att undersöka om ett FPGA-kort av typen Stratix II DSP Development Kit är ett lämpligt utvecklingskort för att ta fram en prototyp av systemet. Kortet har undersökts med avseende på olika begränsningar för det utvecklade systemet, till exempel vilka frekvenser en inSignal kan samplas i.Ett annat användningsområdet för systemet är möjligheten att få alla sampels lagrade på kortet presenterat i en textfil på en ansluten PC.

This paper investigates whether the traditional accrual based trading strategy first documented by Sloan (1996) can be refined using fundamental analysis. Specifically, this is done by implementing the composite Signal F_SCORE introduced by Piotroski (2000) to identify financially strong or weak firms. We find that by applying both investment models simultaneously, in a model we call P_KOMB, the mean market-adjusted return earned by an investor exploiting the accrual anomaly can be increased by 14.8% annually. This is achieved by taking a long position in strong firms (as defined by the composite Signal) in the lowest accrual portfolio, while an offsetting short position is taken in weak firms in the highest accrual portfolio, repeated annually between 1997 and 2007. Consistent with prior studies, positive market-adjusted returns can be attained through assessment of accruals as well as key value drivers found in historical financial data.

This report describes how to process audio Signals in real time with a digital Signalprocessor. The digital Signal processor used in the thesis and described in the reportare the Blackfin processor ADSP-BF537 from Analog Devices.In the body of this report there is theory of the processor characteristics and thevarious programming languages used. All experiments that were made on theprocessor are described, these descriptions also help in understanding the annexeswhere the experiments will be presented. The body of this report also describes theprogram used to do experiments. Testing the CPU limit was done and the results arepresented to get a good view of what it can handle.

Softube has developed DSP-card and software for simulation of the sound of old tube amplifiers. The purpose with this thesis is to design a compact amplifier with high power to function together with the DSP-card and build a unit that can replace several other guitar amplifiers. The advantages with that kind of solution could be that it would be cheaper, easier to carry and easier to stor than the real amplifiers. The amplifier that has been designed is of class D type with digital PWM modulator. There is several types of amplifier modules on the market that use analog input Signal, but if one of them would be used a D-A converter is needed on the DSP card.

The report aims to investigate how well a certain type of affordable embedded single board computer can hold up against today's more expensive computers in a computer system by doing various tests on a system with the specified requirements. The system has a Raspberry Pi as the single board computer which task is to control a camera based on coordinates obtained from a server as well as capture and stream a video Signal on a network.The researches were conducted to check how much network traffic a single-chip computer sent in different video formats and how much CPU utilization was required. Studies were also made to ensure the accuracy of the camera control. The researches have been experimental, where several tests have been performed and analyzed.The results show that a sufficiently good accuracy can be obtained from the camera steering unit, in which two different servos have been investigated. When the video format MJPEG and H.264 are used, the single-chip computer is able to transmit a video Signal up to 1280x720 at 15 fps.

Genom samtal med radioamatörer visade det sig att det fanns ett intresse för att använda rumsdiversitet på deras mottagare då de upplevde fädning (vid körning med bil) som ett problem för hörbarheten. I ett system där mottagaren är stationär och sändaren mobil kommer den mottagna Signalen att fäda ibland då radiovågorna tar olika vägar till mottagaren och ibland förstärker och ibland stör varandra. Tanken med detta examensarbete var att kunna ta emot två bandbegränsade audioSignaler från två mottagare med varsin antenn som tar emot samma Signal (rumsdiversitet) och vikta ihop dessa med lämplig metod för att få ut en bättre Signal. Om man kunde implementera ett diversitetssystem med VHDL i en FPGA så skulle man få ett system som var både billigt och flexibelt. I det här examensarbetet har jag försökt att konstruera ett sådant system..

When a helicopter is flying, the dynamics vary depending on, for example, speed and position. Hence, a time-invariant linear model cannot describe its properties under all flight conditions. It is therefore desirable to update the linear helicopter model continuously during the flight. In this thesis, two different recursive estimation methods are presented, LMS (Least Mean Square) and adaptation with a Kalman filter. The main purpose of the system estimation is to get a model which can be used for feedback control.

The aim of the work was to investigate the possibility to combine information from PPG and bio-acoustic technology to extract information that is related to the blood pressure. The measurements have been carried out with several different configurations. First the relation between arterial sounds and the PPG-Signal was studied. After those measurements with both PPG and the bio- acoustic technique was concluded on people in different positions and after riding a bike. The goal was to vary the blood pressure.

Embedded Systems Lab at Umeå University is currently part of a research project with the purpose to examine the behavior of dairy cows inside a barn. Each cow needs to be tracked with a precision of 50 cm, and since GPS-technique has poor functionality at indoor environments, an indoor positioning system needs to be developed.Embedded Systems Lab has already developed an indoor positioning system using IR-light and radio, but since this system demands extensive infrastructure and is rather expensive, an alternate positioning system using ultrasonic pulses and radio is being examined.In this report the range, beam angle and current consumption of ultrasonic transmitters- and receivers are investigated. Three different driver stages for the transmitter is tested, and two amplifier solutions for the receiver. The report also describes how the length of the transmitted ultrasonic pulse affects the received Signal, accessibility of a ?shadowed? Signal, and the effect of different sound frequency..

Active headsets have been on the market for years and now it is time for something else to enter the stage. The technology of active noise reduction can for exmple also be used in ventilation systems for reducing ventilation noise. An active control system principally consists of four important components, namely the downstream error microphone, the upstream detection or reference microphone, the digital Signal processor (DSP) and a loudspeaker. The upstream reference microphone listen to the primary ventilation noise and sends it to the DSP which makes a phase shift to the Signal and sends it to the loudspeaker. The loudspeaker sends out the opposite waveform of the incoming one and reduce the primary ventilation noise.

This project started when LIC Audio AB wanted help with development of a hearing aid for public rooms. The problem is that a lot of people suffer from some sort of hearing impairment. In places with a lot of people and background noise the problem becomes bigger and the sound seems to flow together. During the project we found the solution for the problem in the shape of a headphone. The headphone receives a Signal from a preinstalled hearing loop.

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.

En modern grafikprocessor är oerhört kraftfull och har en prestanda som potentiellt sett är många gånger högre än för en modern mikroprocessor. I takt med att grafikprocessorn blivit alltmer programmerbar har det blivit möjligt att använda den för beräkningstunga tillämpningar utanför dess normala användningsområde. Inom det här arbetet utreds vilka möjligheter och begränsningar som uppstår vid användandet av grafikprocessorer för generell programmering. Arbetet inriktas främst mot Signal- och bildbehandlingstillämpningar men mycket av principerna är tillämpliga även inom andra områden.Ett ramverk för bildbehandling implementeras och några algoritmer inom bildanalys realiseras och utvärderas, bland annat stereoseende och beräkning av optiskt flöde. Resultaten visar på att vissa tillämpningar kan uppvisa en avsevärd prestandaökning i en grafikprocessor jämfört med i en mikroprocessor men att andra tillämpningar kan vara ineffektiva eller mycket svåra att implementera..

This thesis is divided in to two different parts. The first part includes examination of the measurementsystem of an industrial robot using a resolver sensor. The main focus is on methods for suppressing noise in the angularvelocity Signal without increasing timedelay. Five different methods are investigated. Three of these are based on oversampling: burstsamplingmethod, meanvaluemethod and correlationmethod.

Detta examensarbetet undersöker möjligheten att eliminera de amplitudtoppar som uppstår då flera sinusSignaler av slumpmässiga frekvenser adderas. Det som eftersträvas är en Signal innehållande flera godtyckliga frekvenser samtidigt som den bibehåller en låg Crestfaktor (eller PAPR). De metoder som tas fram implementeras sedan i en FPGA. Rapporten behandlar de metoder som undersökts både i teoretiska utvärderingar samt i en hårdvaruimplementation. Resultaten visar på att det inte finns någon enkel lösning på problemet, men att en kombination av metoder kan användas för att få en förbättring av Signalens Crestfaktor.