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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

An Efficient On-Demand Point-To-Point Piconet Formation Scheme for Bluetooth Personal Area Network

Lee, Song-Ying 03 September 2004 (has links)
In the short-range wireless communication and networking, Bluetooth is a promising technology, mainly used as a replacement for connected cables. Since the Bluetooth specification only defines how to build a Piconet, several solutions have been proposed to construct a Scatternet from the Piconets in the literatures. The process of constructing a Scatternet is called the Scatternet formation. The traditional scatternet formation has three defects: First, more power and time need to be consumed in order to construct the scatternet. Second, after the scatternet is formed, more power and bandwidth are required to maintain the connection of scatternet. Third, due to the restriction of topology, the communication between two nodes must be relayed through the bridge or master, even when they are in the communication range. In this thesis, we propose a novel method in the transmission ranges of all the other nodes to form temporary point-to-point piconet only when two nodes want to communicate with each other. When the communication is finished, the temporary point-to-point piconet is destroyed immediately. Two nodes in the communication range can communicate with each other directly without the relay node. Our On-Demand Point-To-Point Piconet Formation (ODP2P) scheme resolves the defects of traditional scatternet formation in communication range. In order to reduce the communication delay, every node owns its list to record the information of all nodes within the communication range. An on-event method maintains the list. Network performance analysis and simulations show that our method can reduce the routing path significantly, provide better utilization for Bluetooth personal area network (PAN), and maintain the range list efficiently.
12

A Novel Scatternet Scheme with QoS Support and IP Compatibility

Tan, Der-Hwa 03 August 2001 (has links)
The bluetooth technology encompasses a simple low-cost, low-power, global radio system for integration into mobile devices to solve a simple problem: replace the cables used on mobile devices with radio frequency waves. Such devices can form a quick ad-hoc secure "piconet" and communicate among the connected devices. While WLANs had good ad-hoc networking capabilities, there was no clear market standard among them. Moreover, there were no global standards that can be integrated and implemented into small handheld devices. Some market analysts predict that there will be some 1.4 billion Bluetooth devices in operation by the year 2005 [1]. That is the reason we replace the cable from the "Network Adapter" with a low-cost RF link that we now call Bluetooth. However, the current specification1.1 [2][3] does not describe the algorithms or mechanisms to create a scatternet due to a variety of unsolved issues. Since the upper layers are not defined in Bluetooth, it is not possible to implement scatternet in current specification. Hence in this research, we need make some modifications to Bluetooth protocol in order to support the transmissions of packets in scatternet. In this paper we describe a novel scatternet architecture, and present link performance results of the proposed architecture.
13

Simuleringar av Bluetooth mesh-nätverk i ett dynamiskt och storskaligt tätbefolkat område

Persson, Isadora, Ahlberg, Oliver January 2016 (has links)
Mobil datakonsumtion har drastiskt ökat de senaste åren vilket belastar de existerande kommunikationsnätverken. I och med den ökade belastningen av existerande infrastrukturer krävs det nya kommunikationslösningar. Detta har i sin tur skapat ett behov för dataavlastning på fasta nätverk, exempelvis Wi-Fi-nätverk. I denna studie undersöker vi genom simuleringar hur vi kan underhålla ett storskaligt och dynamiskt Bluetooth meshnätverk i en miljö likt Stortorget under Malmöfestivalen. Vi implementerar en nätverkstopologi för Bluetooth, scatternettopologin, i nätverkssimulatorn NS-3 och utför simuleringar där vi provocerar förändringar i topologin. Resultaten av våra simuleringar visar på att nätverket lyckas återhämta sig vid förändring i topologin, att scatternettopologin minst klarar av 240 dynamiska mobila noder samt att max 3 noder påverkas vid förändringar i topologin för simuleringar av upp till 240 noder. / Mobile data consumption has drastically increased in the recent years which stress theexisting communication networks. As an effect of the increased load a demand for newcommunication solutions has arisen, creating a need for data offloading onto fixed networks such as Wi-Fi. In this thesis, we aim to study how to maintain and reconstruct a large and dynamic Bluetooth mesh network in an environment such as Stortorget during Malmöfestivalen. We implement a network topology specific for Bluetooth, the scatternet topology, in the network simulator NS-3 and run simulations in which we provoke changes in the network topology. The result of our simulations shows that the network is able to heal itself when the topology changes, that the scatternet topology can manage up to 240 dynamic mobile nodes and that at most 3 nodes are affected when the topology changes during simulations of up to 240 nodes.
14

Wireless Multi-Sensor Feedback Systems for SportsPerformance Monitoring : Design and Development

Sturm, Dennis January 2012 (has links)
Wireless applications have become a common part of daily life. Whether it is mobile phones, the Wi-Fi router at home, the keycard which has replaced the car key, a radio frequency identification access system to a building or a Bluetooth headset for your computer or phone, the means of modern wireless data exchange is an omnipresent technology. In sports, the market is in its infancy for wireless, technical applications or gadgets. Only heart rate monitors and GPS watches are currently used by recreational athletes. Even though most of the larger sports equipment companies regularly launch new products related to sports performance monitoring and mobile phone technology, product innovation leaps are rare.In this work the design of a wireless sports performance measurement platform is presented. Using the example of kayaking, this platform is configured as a paddle performance measuring system, the Kayak XL System, which can monitor propulsive paddle force, paddle kinematics and boat velocity, interalia. A common mobile phone platform has been chosen as the user interface for this system. The design approach focussing on user requests, demands and expectations in combination with the process of iterative technical development are unveiled in this thesis. An evaluation of the system is presented and the work is finalised with an overview of further systems which have been designed based on the developed measurement platform. The Kayak XL System is a flexible system designed to be mounted onto any standard kayak paddle and installed in any competition kayak. Versatility, unobtrusiveness and usability were major design concerns. The developed system consists of four modules plus a software which has been designed for Android mobile phones. The phone communicates with each of the four modules trough Bluetooth radio. These four modules are also referred to as nodes and have specific measurement purposes. Two nodes have been designed to measure paddle force and kinematics, one node has the purpose to measure foot stretcher force and boat motion data, and the fourth node enables a more convenient method of calibrating paddle force measurement. The fourth node is therefore only needed prior to performance data acquisition. Results show that paddle and foot stretcher force can be measured with a resolution below 1N after calibration. Installing the paddle nodes on a previously configured paddle without repeated calibration is facilitated with the compromise of a doubled error margin. The default sampling frequency is set to 100 Hz and can, like all system parameters, be configured on the mobile phone. Real-time computation of complex performance parameters is only limited by the phone CPU. The system adds twice 109 g to the paddle and approximately 850 g to the kayak, excluding the mass of the mobile phone / <p>QC 20120827</p>
15

Traffic Engineering in a Bluetooth Piconet

Dahlberg, Anders January 2002 (has links)
The Bluetooth technology is still in an early stage of development. Much more research can and will be done before the performance of Bluetooth reaches its peak. During the recent years, ideas to integrate Bluetooth units in larger networks have arose, with the Bluetooth unit in the role as access point to the network. This behavior opens up for new possibilities but also increases the requirements on performance. In this thesis the main topic is improvement of piconet performance. The piconet, with the Master unit as access point, is studied from a teletraffic engineering point of view. Different performance attributes and behaviors have been found and investigated. With the outcome of these investigations in mind, new and more efficient policies and algorithms are proposed for both data and voice. A policy increasing the utilization of available bandwidth in a piconet is presented. Furthermore, a proposal is presented where multiple Bluetooth units are used in an efficient manner to support voice calls. The proposed solution does also enable creation of simple teletraffic models to be used for dimensioning. / Phone: +46709138850

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