The number of wireless networks has increased rapidly among both home users and companies in just a few years. That has brought a lot of good things with it, for example the possibility to connect wireless equipment to the network or Internet from an arbitrary position within range of the accesspoint. But since the transmissions take place through the air some new security risks appear. It?s difficult to restrict the signals to a specific space and thereby a lot easier for unauthorized to eavesdrop or disturb the signals compared to a traditional wired network.

The objective of this diploma work is to investigate a set of Multiple Input Multiple Output (MIMO) channel models compatible with the emerging IEEE 802.11n standard. This diploma work validates also advanced, innovative tools and wireless technologies that are necessary to facilitate wireless applications while maximizing spectral efficiency and throughput. MIMO channel models can be used to evaluate new Wireless Local Area Network (WLAN) proposals based on multiple antenna technologies. The purpose of this thesis is to investigate means of channel models and their implementation in different environments such as: Matlab, C++ and Advanced Design Systems (ADS). The investigation considers also a comparison between the channel models based on theoretical data and parameter setup to the channel models based on statistical characteristics obtained from measured data.

AbstractTitle: Wireless Fidelity ? A Scenario Analysis Authors: Mellberg Ola, Technology Management, Lund UniversityMårtensson Jens, Technology Management, Lund University Tutors: Andersson Jens A, Faculty of Engineering LTHKarlberg Johan, Sony Ericsson Mobile Communication ABSvensson Claes, Lund University Discussion: The most significant impacts on the telecom industry over the past decades have been the rapid growth of the Internet and mobile telephone services. Currently these two worlds are converging. Moreover, the fast expansion of wireless high capacity Internet access, increased distribution of local/public hotspots and rapid development of wireless network cards have opened new opportunities for the mobile telecom industry. Research Questions:To what extent could the explosion of local and public wireless networks, using WiFi technology, affect the future telecom industry? Who will ultimately master the WiFi innovation and to what degree could this innovation open new possibilities for external players to enter the mobile voice industry? Purpose: The purpose of the Master Thesis is to provide Sony Ericsson Mobile Communication AB with the most transformational scenarios, which will enable employees to recognise patterns and interpret the meaning of WiFi-related events as they unfold.

This report describes the manufacture and control of a flying platform. The report describes the basic and fundamental theories required to get the platform flying. It touches on subjects such as A/D-conversion. PWM-control and PID-control. The sensors used in the platform are a gyro and an accelerometer.

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This report describes the manufacture and control of a flying platform. The report describes the basic and fundamental theories required to get the platform flying. It touches on subjects such as A/D-conversion. PWM-control and PID-control. The sensors used in the platform are a gyro and an accelerometer.

Nowadays Wireless LAN is playing a more and more important role in network systems. After 1999, in which the IEEE organization published its Wireless Local Network standard 802.11[1], many people saw the advantages of the standard but also the lack of support for multimedia streaming. A lot of research work has been done on the proposed IEEE 802.11e standard draft during the past 4 years. It is supposed to be able to fully support Quality of Service. The final version will be published early in 2004.

The security solutions used in wireless home networks are examined in this report. Thegrowing number of wireless units have increased the need for reliable security solutions.This report aims to enlighten the reader about the fundamental technology used inwireless security solutions and inform about the existing flaws. A recommendationabout how to achieve a high level of security in the home network is also given to thereader.Several flaws in the security solutions in use have been reported. Of these the mostsevere has been examined in a test network using highly accessible tools to get aperception of how vulnerable the user is.The tests showed that several attacks were efficient and easily carried out. We have alsoseen that several of the home networks in our sample are susceptible to these attacks.Our survey revealed that the Internet service provider's technical support in many caseslacked the knowledge necessary to inform the user about reliable security solutions..

In many clinical applications, it is desirable to transmit sensor information wireless. In earlier research, investigation transmit ECG signal using Bluetooth, was performed. However, when Bluetooth has some drawbacks it is of interest to investigate alternative methods, one such method is ZigBee. Bluetooth has higher data rate speed (1Mbps) than ZigBee (250kbps). However, Bluetooth consumes more power.

According to the study [1] several firefighters are killed in action each year. This happens naturally in various ways. One of the major factors is that firefighters often do not know how the environment looks like, for example that a building in an industrial area contains hazardous gas cylinders. Without a solution, fire-fighters will continue to die in duty. It is therefore important to solve this problem so that we can minimize the risks and save lives.The goal of this project was a control system for pneumatic artificial muscles.

TCP (Transmission Control Protocol) is a transport protocol designed for the wired Internet. In wireless networks packet losses occur more frequently due to the unreliability of the physical link. The main problem is that TCP treats all losses as congestion, which leads to a lower throughput. Ad hoc networks are multihop wireless networks of mobile nodes, where each node can allow other packets to pass through it. Topology changes often occur and may lead to packet losses and delays, which TCP misinterprets as congestion.

On some occasions it may be inappropriate with a cameraman behind the camera. In somecases there is no cameraman available or it is a smaller event, like a family celebration, to befilmed. It can also be difficult for a cameraman to shoot from certain angles. One solution forthis kind of situations can be to remotely control the camera movements. There are thosekinds of solutions on the market today but they either address professional filmmakers or thefunctionality is limited, for example by the absence of wireless remote control.This project aims to develop a solution to the problem with absence of wireless remote controland also a solution with more flexibility and less complexity than today?s solutions.

This thesis investigates techniques for stealth hydroacoustic communication using spread spectrum. The Swedish naval defense organisations have a vision that all their units should be able to communicate with each other, even between underwater vehicles. But the properties of water makes it a complex channel to use for wireless communications. Radiomagnetic waves have very limited range in water, therefore acoustic waves are used. In this report the basics of wireless communication systems are described including source coding, channel coding, modulation techniques as well as different techniques for spread spectrum.

In today?s industry it is starting to get more and more interesting with wireless systems and solutions for applications. To be able to reduce the amount of cables drawn to various machines which takes both space and an extra fee for every cable drawn. Some systems might require the user to use a handheld device that is directly connected by a cable which in some machines might be inelegant for the user.The goal with this bachelor thesis is to develop wireless monitoring of the machine operators position that is working with heavy industrial machinery. The thesis started out with researching different techniques for positioning a transmitter indoors, this was done in order to get a better understanding on how to go about.

On children born with a complete cleft lip and palate (CLP) the repair of the alveolar ridge doesn´t take place before the children are about ten years old. This results in that they have a residual cleft in the alveolar ridge during their early childhood. This residual cleft, and the oronasal fistulas that may appear after the repair of the hard palate, can result in a negative influence on the speech of the children. Thereby it may be necessary with cover for examplewith a palatal plate or an obturator. At the Department of Orthodontics, at Linköping University Hospital, Sweden, some of the children with CLP undergo treatment with sustained palatal fistula obturation in order to cover fistulas or residual clefts.