"Body area networks (BAN) is a technology gaining widespread attention for application in medical examination, monitoring and emergency therapy. The basic concept of BAN is monitoring a set of sensors on or inside the human body which enable transfer of vital parameters between the patient´s location and the physician in charge. As body area network has certain characteristics, which impose new demands on performance evaluation of systems for wireless access and localization for medical sensors. However, real-time performance evaluation and localization in wireless body area networks is extremely challenging due to the unfeasibility of experimenting with actual devices inside the human body. Thus, we see a need for a real-time hardware platform, and this thesis addressed this need. In this thesis, we introduced a unique hardware platform for performance evaluation of body area wireless access and in-body localization. This hardware platform utilizes a wideband multipath channel simulator, the Elektrobit PROPSimâ„¢ C8, and a typical medical implantable device, the Zarlink ZL70101 Advanced Development Kit. For simulation of BAN channels, we adopt the channel model defined for the Medical Implant Communication Service (MICS) band. Packet Reception Rate (PRR) is analyzed as the criteria to evaluate the performance of wireless access. Several body area propagation scenarios simulated using this hardware platform are validated, compared and analyzed. We show that among three modulations, two forms of 2FSK and 4FSK. The one with lowest raw data rate achieves best PRR, in other word, best wireless access performance. We also show that the channel model inside the human body predicts better wireless access performance than through the human body. For in-body localization, we focus on a Received Signal Strength (RSS) based localization algorithm. An improved maximum likelihood algorithm is introduced and applied. A number of points along the propagation path in the small intestine are studied and compared. Localization error is analyzed for different sensor positions. We also compared our error result with the Cramèr- Rao lower bound (CRLB), shows that our localization algorithm has acceptable performance. We evaluate multiple medical sensors as device under test with our hardware platform, yielding satisfactory localization performance."

This master thesis aimed to develop a prototype of a hardware platform which allowed digital communication as well as DC power to be transmitted over one pair of wires. The prototype was used as a pre-study for Axis Communications AB that wanted a bit rate high enough to transmit digital audio, as well as enough power to supply a set of speakers. The prototype included one circuit to send power and data (master), as well as two receivers (slaves). With this configuration data rates of up to 17 Mbps were achieved as well as an output power of 90 W from master. The data was transmitted on a RS-485 bus type, which was AC coupled to a 48 V DC bias. Because of the AC coupling, the bit stream needed to alternate, therefore Manchester encoded data, or similar, was recommended. The receiver cards included a buck converter to supply the circuits with a stable 5 V DC. The converters needed at least 10 V supply voltage to function, which gave a theoretical max range in cabling when accounting for voltage drop in the cables. For a 0.75 mm² power cord at max allowed current, this range was 500 metres per wire.

Fueled by increasing human appetite for high computing performance, semiconductor technology has now marched into the deep sub-micron era. As transistor size keeps shrinking, more and more transistors are integrated into a single chip. This has increased tremendously the power consumption and heat generation of IC chips. The rapidly growing heat dissipation greatly increases the packaging/cooling costs, and adversely affects the performance and reliability of a computing system. In addition, it also reduces the processor's life span and may even crash the entire computing system. Therefore, dynamic thermal management (DTM) is becoming a critical problem in modern computer system design. Extensive theoretical research has been conducted to study the DTM problem. However, most of them are based on theoretically idealized assumptions or simplified models. While these models and assumptions help to greatly simplify a complex problem and make it theoretically manageable, practical computer systems and applications must deal with many practical factors and details beyond these models or assumptions. The goal of our research was to develop a test platform that can be used to validate theoretical results on DTM under well-controlled conditions, to identify the limitations of existing theoretical results, and also to develop new and practical DTM techniques. This dissertation details the background and our research efforts in this endeavor. Specifically, in our research, we first developed a customized test platform based on an Intel desktop. We then tested a number of related theoretical works and examined their limitations under the practical hardware environment. With these limitations in mind, we developed a new reactive thermal management algorithm for single-core computing systems to optimize the throughput under a peak temperature constraint. We further extended our research to a multicore platform and developed an effective proactive DTM technique for throughput maximization on multicore processor based on task migration and dynamic voltage frequency scaling technique. The significance of our research lies in the fact that our research complements the current extensive theoretical research in dealing with increasingly critical thermal problems and enabling the continuous evolution of high performance computing systems.

In a way to help doctors and medical students train on performing difficult surgeries before entering the stressful operating room, DevinSense is developing a generic hardware platform for medical simulation. The system is used together with specific simulation software derived from real patient data and optimized towards the user specifications. The hardware platform will enable training for the operator to develop basic surgical skills effectively without the risk of losing the patients and avoiding the hospital daily contrails. The trainee on the simulator sees the scene displayed in real 3D-stereoscopic mode through a semi-transparent mirror and controls the surgery tools with a 6-DOF force feedback device. Thus, the simulated procedure becomes nearly identical to the real surgery. This project aims to develop a conceptual hardware platform for the medical simulator. The proposed solution should be height adjustable to different users. It must also include additional ergonomic functions such as mobility and suitable for use within the working environment. Accordingly, two conceptual prototypes are manufactured and evaluated. The first conceptual prototype is developed to check if the setup provides a good experience for the users, and to dimension the size of the components and to determine their location to set targets for the second prototype. The resulting product of the second prototype is one leg-lifting column with aluminum profile mounted on the top of it. The semi-transparent mirror, secondary monitor, haptic device and additional components are mounted on the setup to deliver the desired functions. The mechanical development is done using Autodesk Inventor. ANSYS is used to simulate the setups’ stresses and vibrational response to ensure that the system will perform optimally. MATLAB is used for mathematical modeling. The test results of the second prototype were promising where the height can be adjusted for users between 155 cm and 200 cm. Furthermore, the prototype provides stable and stiff design while operating on the simulator as well as transporting it. / För att hjälpa läkare och läkarstudenter att träna på att utföra svåra operationer, utvecklar DevinSense en generisk hårdvaruplattform för medicinska kirurgi-simulatorer. Systemet används för specifika simuleringsprogram som kommer ifrån verkliga patientdata och är optimerad med avseende på användarens specifikation. Hårdvaruplattformen möjliggör utbildning för operatören att utveckla grundläggande kirurgiska färdigheter effektivt utan risk för patienterna. Den som utbildas på simulatorn ser operationssimuleringen som en verkligt 3D-stereoskopisk bild genom en halvgenomskinlig spegel och styr kirurgiverktyget med en 6-DOF haptisk-enhet. Simuleringen kommer att kännas som en riktig operation. Syftet med projektet är att utveckla en prototyp av en haptisk plattform för en medicinsk simulator. Prototypen bör vara justerbar i höjdled för att passa olika användare. Den måste också innefatta ytterligare ergonomiska funktioner som till exempel att vara lätt att transportera. Följaktligen har två prototyper tillverkats och utvärderats. Den första prototypen utvecklades för att kontrollera om den ger en bra upplevelse för användaren, för att dimensionera komponenterna och för att bestämma deras platser. Detta för att sätta upp mål för den slutgiltiga prototypen. Den slutgiltiga prototypen har en linjärenhet som är monterad på en bottenplatta och en aluminiumprofil som är monterad ovanpå linjärenheten. Den halvgenomskinliga spegeln, sekundära bildskärmen, haptiska enheten och ytterligare funktionsenheter har även monterats på aluminiumprofilen. Autodesk Inventor användes för att designa prototypen. ANSYS användes för att analysera spänningar och vibrationsbeteende hos prototypen för att säkerställa att systemet kommer att fungera tillfredställande. MATLAB användes för matematisk modellering. Testresultaten för den andra prototypen blev lovande. Höjden kan justeras för användaren, som är mellan 155 och 200 cm lång, den är stabil när användaren använder haptikenheten och den är även stabil när användaren ska förflytta prototypen till ett annat rum.