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14 Uppsatser om Antennas - Sida 1 av 1

Framtidens mobilnät

The purpose of this project was to study how the interference between two Antennas in a MIMO system affects the linearity of the power amplifiers powering the Antennas. For the MIMO system, two power amplifiers and twoAntennas were constructed and designed using the software ADS and a software defined radio was constructed using the platform USRP and the software LabVIEW. The result was that the interference between the Antennas affectsthe linearity of the power amplifiers powering the Antennas adversely and a reasonable theory was that the interaction decreases inversely proportional tothe square of the distance..

LIN baserad kommunikationsmodul för GPS

The work that is the basis of this Master Thesis was performed on Scania´s group of cabdevelopment, and concerns the GPS-system in Scania´s trucks. Today, the GPS-systemconsists of an active antenna mounted on the roof of the truck. The antenna is connectedto the receiver with a coaxial cable.The purpose with this Master Thesis was to develop and evaluate a new GPS-system,where the information is distributed using a LIN-network. Today, each unit requiringGPS-information is equipped with its own antenna and receiver. This solution has beenthe most cost effective to this point.

Radioräckviddsberäkningar för flygande plattformar

There exist several known methods for calculation of radio coverage for ground-based systems. As far as we know there are no equivalent methods for the case of flying platforms when the altitudes and speeds are significantly different to those of ground-based systems. This thesis describes the theoretical concepts behind calculations of radio coverage for flying platforms. An investigation is made to sort out what is important and possible to employ in a model for simulations. A method is described and implemented in a program for evaluation of flying radio systems.

Reglering av vridbord

This report describes a master thesis performed at Saab in Arboga. The main purpose was to build a controller for a system containing a turn table and an antenna beam. The idea is to use this system on a boat where it will be exposed to position disturbances due to waves. The desired behaviour is that Antennas placed on the antenna beam should point towards the same target all the time. To solve this problem the system has been modeled and simulated in Matlab and Simulink.

Youngbloods

The goal of this project was to create the music video for swedish pop/rockband Antennas? single Youngbloods, from their album Feeling Feline Tonight(2009). The video was made through animation, collages, photography andillustration. The main focus for the video was to create an independent visualstory and to implement an investigation of how different technics for creatingand documenting images and motion result in different interpretations of thecontent. The work was characterized by an active search for contrasts andcontradictions.My approach to the project was to work with a child?s curiosity, but withthe discipline of an adult.

SafeTool : Implementering av RFID-teknologi i maskiner för byggbranschen

Every year more than 6000 thefts, to a value of 1.5 billion SEK, are reportedwithin the Swedish building trade. Plus all the indirect costs of having theconstruction site standing still.SafeTool is a newly started company that will try to prevent this problem witha modern technology solution.The key to SafeTool?s solution is RFID ? Radio Frequency Identification ? andthe solution looks like this;All tools are stored in a container on the construction site. Every tool isequipped with a RFID-tag that uniquely identifies the tool. With Antennas in thecontainer it is possible to detect when a tool is leaving the container and whenit comes back.

Lokalisering av skidor i lössnö : Självständigt arbete i Teknisk Fysik

This report studies the possibility of using some sort of radio sender and transmitter in order to position skis lost in powder snow. It is concluded that a RF-solution on the 433 MHz frequency should be the most efficient. Different forms of directional Antennas are examined and studies show that in theory the best suited is the so called ?Yagi-Uda antenna?. A solution based on using a Receive Signal Strength Indicator value together with the above mentioned directional antenna is developed.

Spelutveckling och lansering av applikation till Android

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the Antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

Experimentell konstruktion av pickupsystem anpassat för trummor med hjälp av MATLAB

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the Antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

Undersökning av vissa beläggningars påverkan på antenners effektivitet i tågmiljö

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the Antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

Beteende inför lek hos odlad respektive vild lax (Salmo salar L.) i Klarälven

In many regulated rivers, authorities have stocked hatchery salmon to compensate for loss of wild populations. However, hatchery fish have not always behaved as wild fish do, and stocking them has not always fully compensated for the loss of wild fish. The purpose of this study was to compare swimming behaviour in the river before spawning, the choice of spawning areas and body size between wild and hatchery-reared salmon in the river Klarälven. Salmon behaviour in the river before spawning was analyzed using radio telemetry. The salmon were caught at Forshaga power plant, radio-tagged and returned to Klarälven at Ekshärad, 107 km from the river?s mouth.

Passage efficiency and migration behavior for adult Atlantic salmon at a Half-Ice Harbor fish ladder

Due to exploitation of the world?s rivers, the upstream migration of anadromous species is frequently delayed or even prevented. To mitigate these problems and allow fish to migrate past obstacles, structures such as fish ladders have been developed. However, recent studies show that many of the present fish passage facilities are deficient. Monitoring and evaluation of passage facilities is therefore crucial to enable necessary adjustments.

CARABAS III Konstruktion av antenninstallation på helikopter

This report describes the construction work of a radar antenna for the radar systemCARABAS. CARABAS is a long wave airborne ground radar that has been developed bySAAB Microwave Systems and will now be mounted on a small helicopter, Schweizer 300.The antenna should be able to fold up and down. When the radar is in use the antenna islowered and under transport, start and landing the antenna is folded up. An emergency dropfunction should also be included in the design of CARABAS III.The extent of this report includes construction of the antenna, frame structure attached to thehelicopter, mechanism for folding the antenna up and down and mechanism for emergencydrop function. The mechanical design of the antenna and frame structure is based on modaland stress analysis, vibration measurement of Schweizer 300 and frequency analysis, andcalculations regarding aerodynamic drag and mechanics.The exciting frequencies of the helicopter and accelerations at those frequencies weredetermined by vibration measurement and frequency analysis.

Radiolänk med GNU Radio

At the Department of Technology and Built environment at the University of Gävle there was an interest to study GNU Radio, which is an "open source radio project. The project is based on that most of the radio signal processing is made in an ordinary PC. The idea behind this degree project was that in a laptop there are several radio transmitters/receivers that takes space, generates heat and transmit in varied frequency band etcetera. All these radio transmitters/receivers could be replaced with a Software Defined Radio system. It means that one common, general radio hardware is used to different communications such as: WLAN, Bluetooth, GPRS, 3G etcetera. The waveform is generated in the software, which makes the system very flexible.