Dissertations / Theses on the topic 'Wireless'

This document contains the development of an amplifier for an ECG-signal and interfacing it to wireless communication. The purpose of this project is to get a clear ECG-signal without any noise, save it and send it through wireless communication.A challenge of the wireless communication unit is to send as little information as possible to make the communication faster, without loss of information in the ECG-signal.The context for this project is the integration of wireless communication in medical applications for home healthcare. This means that, patients are no longer bound to a specific healthcare location where they are monitored by medical instruments. Wireless communication will not only provide them with safe and accurate monitoring, but also the freedom of movement.

Exploitation of wireless sensor networks (WSNs) in ubiquitous computing environments is continuously increasing for gathering data. Contemporary distributed software systems on WSNs for pragmatic business applications have become extremely adaptive, dynamic, heterogeneous and large scaled. Management of such system is not trivial to fulfil these features, leading to more and more complex management and configuration. Along with encompassing state of art and novel techniques for such diversely dynamic system, in this thesis two alternative techniques namely “task initiation by command” and “run-time task deployment and processing” are compared, for such system’s setup and configuration. Both techniques have their own pros and cons which makes them suitable according to the requirements and contextual situations. A lot of effort has been put to make WSNs more and more efficient in terms of computations and power consumption. Hence comparative analysis of both techniques used in this report to setup and configure WSN can be a benchmark to lead towards most appropriate solution to compensate the need of efficient energy and resource consumption.Both alternative schemes are implemented to setup WSN on Sun Microsystems sunSPOT (Small Programmable Object Technology) sensor nodes which are embedded microcontrollers and programmed them in java (j2me). It performs radio communication between wireless sensors and host via sink node also called base station, along with over the air run-time management of sensors. SunSPOTs built in libraries and KSN libraries are used to implement these alternatives and compare the memory footprint, communication pattern and energy consumption.Exploitation of wireless sensor networks (WSNs) in ubiquitous computing environments is continuously increasing for gathering data. Contemporary distributed software systems on WSNs for pragmatic business applications have become extremely adaptive, dynamic, heterogeneous and large scaled. Management of such system is not trivial to fulfil these features, leading to more and more complex management and configuration. Along with encompassing state of art and novel techniques for such diversely dynamic system, in this thesis two alternative techniques namely “task initiation by command” and “run-time task deployment and processing” are compared, for such system’s setup and configuration. Both techniques have their own pros and cons which makes them suitable according to the requirements and contextual situations. A lot of effort has been put to make WSNs more and more efficient in terms of computations and power consumption. Hence comparative analysis of both techniques used in this report to setup and configure WSN can be a benchmark to lead towards most appropriate solution to compensate the need of efficient energy and resource consumption.Both alternative schemes are implemented to setup WSN on Sun Microsystems sunSPOT (Small Programmable Object Technology) sensor nodes which are embedded microcontrollers and programmed them in java (j2me). It performs radio communication between wireless sensors and host via sink node also called base station, along with over the air run-time management of sensors. SunSPOTs built in libraries and KSN libraries are used to implement these alternatives and compare the memory footprint, communication pattern and energy consumption.

This master's thesis will investigate some of the technological solutions available for the construction of a backbone for a wireless citywide network (CWN), such as Wireless Trondheim, and a special attention is given to the possible advantages of using infrastructure already in place. There are several different technologies which can be used as a backbone for the wireless CWN, and in this thesis strengths and weaknesses of the various solutions will be discussed. Some requirements, such as scalability to handle increased capacity demand from future access technologies, may be more important to satisfy than others, and the discussion will see how this might rule out or favor some technology choices. In addition to demands from regular traffic to be carried in the network, also research traffic should be allowed. It is discussed how different requirements as a consequence of this research traffic will set limitations to which technology to use. While the performance of each of the technologies are relatively constant for all cases and easy to determine, the cost of using the different technologies is not. For this reason most effort is put into the analysis of this decision factor. Different possible scenarios are introduced, and the costs of using various technologies in the different scenarios are calculated. The results from the calculations are then discussed in more detail, and an important part of this discussion is sensitivity analysis. The values for several of the parameters used in the calculations will be changed, and the various analyses show how the change of one parameter will affect the result of the calculations. Based on the calculation results and the discussion of the results, some principles which can be used as guidelines in planning and deployment of a backbone for a wireless CWN will be suggested.

Today's communication solution between the vehicle and trailer is one many see as a

non-viable solution, then breakdowns on both the lights and cables are common. Now, a

new innovation enters the market, a system that can transmit wireless control signals

between the vehicle and trailer.

Parvus and Zap, the two solutions that the projekt group has come up with during this

thesis work carried out over the last year on Utvecklingsingenjörsprogrammet.

Technologists Peter Jägevall and Christopher Åberg has developed this project on their

own. The group has developed various concepts and chosen to work on, two of them.

The project has resulted in this report and a prototype

The solution that the group has developed is a wireless communication between vehicle

and trailer. The project team has developed new power-efficient LED lighting fixtures in

order to implement an internal power source in the trailer. The result of this has become

a maintenance-free and wireless product to trailers. The vision is that you in the near

future will see this product on the Swedish roads.

Large-scale deployment of IEEE 802.11 wireless LANs (WLANs) remains a significant challenge. Many access points (APs) must be deployed and interconnected without a-priori knowledge of the demand. We consider that the deployment should be iterative, as follows. At first, access points are deployed to achieve partial coverage. Then, usage statistics are collected while the network operates. Overloaded and under-utilized APs would be identified, giving the opportunity to relocate, add or remove APs. In this thesis, we propose extensions to the WLAN architecture that would make our vision of iterative deployment feasible.

One line of work focuses on self-configuration, which deals with building a WLAN from APs deployed without planning, and coping with mismatches between offered load and available capacity. Self-configuration is considered at three levels. At the network level, we propose a new distribution system that forms a WLAN from a set of APs connected to different IP networks and supports AP auto-configuration, link-layer mobility, and sharing infrastructure between operators. At the inter-cell level, we design a load-balancing scheme for overlapping APs that increases the network throughput and reduces the cell delay by evenly distributing the load. We also suggest how to reduce the handoff time by early detection and fast active scanning. At the intra-cell level, we present a distributed admission control that protects cells against congestion by blocking stations whose MAC service time would be above a set threshold.

Another line of work deals with self-deployment and investigates how the network can assist in improving its continuous deployment by identifying the reasons for low cell throughput. One reason may be poor radio conditions. A new performance figure, the Multi-Rate Performance Index, is introduced to measure the efficiency of radio channel usage. Our measurements show that it identifies cells affected by bad radio conditions. An additional reason may be limited performance of some AP models. We present a method to measure the upper bound of an AP’s throughput and its dependence on offered load and orientation. Another reason for low throughput may be excessive distance between users and APs. Accurate positioning of users in a WLAN would permit optimizing the location and number of APs. We analyze the limitations of the two most popular range estimation techniques when used in WLANs: received signal strength and time of arrival. We find that the latter could perform better but the technique is not feasible due to the low resolution of the frame timestamps in the WLAN cards.

The combination of self-configuration and self-deployment enables the autonomic operation of WLANs.

The key contributions of this research were two-fold. First was the development of an OPNET simulation environment suitable for evaluation of future protocols supporting tightly coupled, heterogeneous WLAN and 3G systems. Secondly was the implementation and testing of the AGG-MAC protocol which aggregates suboptimal size packets together into a single frame, thereby amortizing the overhead.
Ph. D.

Wireless On-board diagnostics functionality, which is a future outlook to vehicle system

parameter analysis, enables measurements and controlling without the limitation of a physical

connector. Today every vehicle must by law provide the possibility to analyze engine and

emission related parameters (OBD II). The wireless connection requires a high security level

to prevent unauthorized communication establishment with the truck’s bus system. The aim

of the project is to make a survey of the available security mechanisms and to find the most

promising solutions. Furthermore, several usage scenarios and access right levels are

specified and a risk analysis of the whole system is made. The greatest challenge is the

specification and implementation of a proper key-exchange mechanism between the analyzing

device and the truck’s bus system, which is therefore carried out with the highest possible

level of awareness. Consequently several different concepts have been formulated based on

the different usage scenarios.

The purpose of the project was to develop the hardware to a microwave wireless system working

at the frequency 2.45 GHz. The functionality of the system should also be easy to understand

since the system is to be used in an educational purpose. Much time has been spent impedance

matching components, a task that proved to be harder than we expected. Other work that has been

is layout of all parts, filter construction and the writing of an easy to understand thesis. After the

parts had been completed, they were tested in a network analyzer and/or spectrum analyzer.

Successful full system test has been done up to 400 meters, the length the system is to be used

for.

In the recent past, wireless sensor networks have been introduced to use in many applications. To

design the networks, the factors needed to be considered are the coverage area, mobility, power

consumption, communication capabilities etc. The challenging goal of our project is to create a

simulator to support the wireless sensor network simulation. The network simulator (NS-2) which

supports both wire and wireless networks is implemented to be used with the wireless sensor

network. This implementation adds the sensor network classes which are environment, sensor

agent and sensor application classes and modifies the existing classes of wireless network in NS-

2. This NS-2 based simulator is used to test routing protocols – Destination-Sequenced Distance

Vector (DSDV), and Ad-Hoc On-Demand Distance Vector (AODV) as one part of simulations.

Finally, the sensor network application models and the extension methods of this NS-2 based

simulator for simulations in specific wireless sensor network applications are proposed.

The past several years have witnessed a rapid development in the wireless network area. So far wireless networking has been focused on high-speed and long range applications. However, there are many wireless monitoring and control applications for industrial and home environments which require longer battery life, lower data rates and less complexity than those from existing standards. What the market need is a globally defined standard that meets the requirement for reliability, security, low power and low cost. For such wireless applications a new standard called ZigBee has been developed by the ZigBee Alliance based upon the IEEE 802.15.4 standard.

The aim of this diploma work is to design fully functional ZigBee and IEEE 802.15.4 modules, and to evaluate an application in a sensor network.

This diploma work has resulted in two fully functional ZigBee and IEEE 802.15.4 modules, respectively. It is also shown that ZigBee sensors can be networked wirelessly. Eventually it is the authors hope that the modules will be used within ITN, and also be developed further for new applications.

Sensor networks have diverse structures and generally employ proprietary protocols to gather useful information about the physical world. This diversity generates problems to interact with these sensors since custom APIs are needed which are tedious, error prone and have steep learning curve. In this thesis, I present RESThing, a lightweight REST framework for wireless sensor networks to ease the process of interacting with these sensors by making them accessible over the Web. I evaluate the system and show that it is feasible to support widely used and standard Web protocols in wireless sensor networks. Being able to integrate these tiny devices seamlessly into the global information medium, we can achieve the Web of Things.