Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 79-81). Also available in electronic version. Access restricted to campus users.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 74-77). Also available in electronic version. Access restricted to campus users.

Wireless communication is becoming more common, a relatively new technology within the area is Bluetooth Low Energy. It’s been developed to be energy efficient and in regard to compatibility. Alongside the growth of wireless technology, scientists and companies are looking for new areas of use. One of these is localization, which means to determine the position of a moving device with the use of stationary devices, an example of this would be GPS.This report means to evaluate indoor localization using Bluetooth Low Energy and was made for Combitech AB in Jönköping. The purpose of the work was to determine with what accuracy and precision the position of a moving device could be estimated. The report will answer the following questions: With what accuracy and precision can the position of a device be determined within a test area of varying size using Bluetooth Low Energy? Is the accuracy and precision affected by the environment?The authors chose an inductive reasoning and therefore intended to answer the questions with the help of experimental studies. A system consisting of both software and hardware was developed and was then used to conduct multiple rounds of tests, where the size of the area and the environment was varied.By evaluating the data gathered from said tests and comparing it to theoretical studies and prior research credible results were obtained. The accuracy appears to decrease as the distance between the units is increased, however a deeper analysis shows that the difference is smaller below 500 cm. No correlation is found between environment and accuracy. When three stationary units, forming a triangle with 400 cm between the vertices, are used to determine the position of a fourth the achieved accuracy is 65 cm. During the tests the precision is not shown to decrease with distance, it seems to vary independently. However, as the environment is changed a noticeable difference is observed. In a gymnasium the standard deviation was calculated to 0.38 RSSIwhereas in an office environment it was 0.99 RSSI. In regard to the given results the authors conclude that Bluetooth Low Energy shows some potential for the use in indoor positioning systems. A possible scenario where the technology would be well suited would be when the units need to work of a coin cell battery for a large period of time, while the system must support multiple types of units and a rough estimation of the position is adequate. / Trådlös kommunikation blir allt mer vanlig i vår vardag, en relativt ny teknik inom detta område är Bluetooth Low Energy som utvecklats med avseende på energieffektivitet och kompabilitet. Parallellt med den trådlösa teknikens spridning letar forskare, såväl som företag, efter nya användningsområden. En av dessa är lokalisering, vilket innebär att med fasta enheter avgöra rörliga enheters position, ett exempel på detta är GPS. Detta arbete handlar om att utvärdera inomhuslokalisering med Bluetooth Low Energy och gjordes på uppdrag av Combitech AB i Jönköping. Syftet var att undersöka med vilken noggrannhet och precision en rörlig enhets position kunde avgöras. Rapporten kommer att besvara följande frågeställningar: Med vilken noggrannhet och precision kan man med Bluetooth Low Energy avgöra en enhets position inom ett testområde med varierande storlek? Påverkas noggrannhet och precision av omgivningen?Författarna valde en induktiv metod och ämnade därför besvara frågeställningarna med hjälp av experimentella studier. Ett testsystem bestående av hård- samt mjukvara utvecklades varpå tester utfördes i flera omgångar, där storlek på område och omgivning varierades. Genom utvärdering av testdata i förhållande till teoretiska studier och tidigare forskning kunde trovärdiga resultat nås. Noggrannheten tycks minska då avståndet mellan enheter ökas, djupare analys pekar på en mindre förlust under 500 cm. Det observeras dock inget samband mellan noggrannhet och omgivning. Då tre fasta enheter placeras med ett inbördes avstånd på 400 cm kan positionen avgöras med 65 cm noggrannhet. Precisionen påverkas under testerna inte av avstånd, signalstyrkevärdena varierar helt oberoende av detta. Vid skifte av omgivning tydliggörs dock en markant skillnad i resultat. I en idrottshall beräknades standardavvikelsen till 0,38 RSSI medan den i en kontorsmiljö var 0,99 RSSI.Författarna drar utifrån det uppnådda resultat slutsatsen att Bluetooth Low Energy har viss potential att användas för inomhuslokalisering. Exempel på ett möjligt scenario där tekniken anses väl lämpad är då de fasta enheterna måste drivas av knappcellsbatterier under en lång tidsperiod, att systemet skall stödja en mängd olika enheter samt att en grov uppskattning av position är tillräcklig.

published_or_final_version / abstract / toc / Electrical and Electronic Engineering / Master / Master of Philosophy

Music today is a big part of a person's everyday life and can influence emotions as wellas initiative and motivation. This effect together with development in technology hasled to that music today is accessible and can be played from a large amount of differentkinds of products. This in turn has meant that the demand for smaller audio playbackdevices is greater than ever.The goal of this project is to develop a concept for energy-efficient speakers withwireless communication that has the ability to obtain and play high quality music. Thespeakers will use the latest available technology and at the same time, using digitalsignal processing, have a low environmental impact through high energy efficiencyand low power consumption. Parallel to this work a pilot study will be conducted tosee trends in listener preference of sound.The result achieves the goals pledged while power consumption in sleep mode is solow that they meet the demands of tomorrow. It also shows that if the time and thewill, and if financial resources are available, it is possible to combine the reducedenvironmental impact with sound quality even for the discerning listener. / Musik är idag en stor del av en persons vardag och kan påverka såväl känslor sominitiativ och motivation. Denna inverkan tillsammans med teknikutvecklingen har letttill att musik idag finns tillgängligt och kan spelas från en stor mängd olika sortersprodukter. Detta har medfört att efterfrågan på mindre ljuduppspelningsenheter ärstörre än någonsin.Målet med detta projekt är att ta fram ett koncept på en energieffektiv högtalare medtrådlös kommunikation som har förmågan att med hög kvalité spela upp musik, användasenaste tillgängliga teknik och samtidigt, med hjälp av digital signalhantering, ha lågmiljöpåverkan genom lägre effektförluster och låg strömförbrukning. Parallellt meddetta kommer en förstudie genomföras för att se trender i lyssnares önskemål avljudkaraktär.Resultatet uppnår ställda mål samtidigt som effektförbrukningen i viloläge är så låg attden möter morgondagens krav. Detta visar att om tid, vilja och ekonomiska resurserfinns att tillgå så är det möjligt att förena minskad miljöpåverkan med ljudkvalité ävenför den kräsne lyssnaren.

Currently, mobile computing is mandating or influencing the direction of new developments in information technology. The high level of adoption that mobile devices have among individuals allows for multiple opportunities for new developments applicable to academic communities, governments and businesses. Data of various types can be collected in a crowd-sourced manner. As such, this thesis examines the collection and application of data collected through a purpose-designed app relying on Bluetooth and geo-location technologies on mobile devices. Through three distinct development iterations and using Bluetooth connectivity, information about connectivity to other mobile devices can be obtained, and in this way the number, type, and device names of “connecting” devices are gathered and stored. Another interesting aspect associated with this type of data collection is that the mobile device may be either moving or stationary during the data collection process. Information can be collected and mined to help map real-life events such as traffic patterns or crowd movement within mass gatherings, as well as ethereal social interactions, and these data can in turn be used as input to various models and simulators. When geo-location technologies are incorporated, a higher level of detail can be obtained on the location of devices. This technology allows for mapping movement and contacts made between people, allowing for the gathering of more detailed social patterns of individuals. As part of this study, the technology developed using Bluetooth connectivity and geo-location is then taken to an additional iteration to develop a mobile system that is able to find and establish direct connections with other individuals and initiate real-life interactions. The work demonstrates that mobile technologies can provide a broad framework of action for the generation and collection of valuable data that can be used for behavioural studies, simulations and other type of research that involves real-life social interactions.

Mobile phones have evolved from being devices just to make phone calls to become smartphones with added capabilities like surfing the network. Wireless communication has played a very important role in the evolution of smartphones. The work in this thesis aims to study the potential to reduce the energy consumption of the 3G communications by using a hybrid architecture. An idea first presented in the paper by Vergara and Nadjm-Tehrani [1]. This architecture consists of a group of nodes that communicate using WiFi or Bluetooth to forward their traffic using one node's 3G interface. In this thesis the named energy sharing scheme is implemented on Android mobile devices and experiments have been performed using a number of realistic traces to assess achievable gains and the energy footprint of the scheme itself. Even though communication technologies, screen features, multimedia capabilities, or processing power have been taken to the highest level, phones' batteries have not improved at the same speed. Nowadays battery lifetime has become a major issue with respect to cellular communication. With 3G communications Internet connection anytime and anywhere is provided to the terminals but this technology is optimized for peak performance whereas in underutilization it wastes a lot of energy. This makes it a big black hole from power consumption point of view when transmitting small amounts of data.

Bluetooth is a low cost and low power wireless technology for connecting portable and / or fixed Bluetooth enabled devices to form short-range wireless ad hoc personal area networks (PANs). As the Bluetooth specification does not specify a protocol to form ad hoc Bluetooth networks, a method for forming an efficient Bluetooth network under a practical networking scenario is still an open research problem. This thesis introduces an approach to implement an indoor ad hoc Bluetooth wireless network, Bluetooth information exchange network (BIEN). This network formation is based on Bluetooth and Java technologies. A set of Bluetooth enabled devices configured with the BIEN software application are able to spontaneously establish a dynamic multi-hop wireless network using Bluetooth technology without the need of formal network infrastructure, centralized administration, fixed routers or access points. In this study, the performance evaluation focuses on the relation between network capacity and topology by testing end-to-end performance in terms of throughput and the latency of communication links with various parameters, including the hop number between nodes and the number of slaves in piconets. The evaluation results show that the throughput reduces with the increased length of a path, and with an increase in the number of slaves in a piconet in the network. The latency also increases with path length, and with the number of slaves in a piconet in the different experimental BIENs, whether if there is traffic or not in the networks. Experimental results have further confirmed the necessity to minimize the number of bridge nodes in the Bluetooth networks due to their traffic bottleneck effect. This work is an attempt at implementation of a distributed multi-hop scatter net with an integrated routing protocol in the practical environments, while most of the literature focuses on covering the modelling of it. It intends to demonstrate how Bluetooth technology with Java technology can be used to design, develop and deploy ad hoc wireless networks with the commercial Bluetooth devices, and examine how well Bluetooth technology supports ad hoc multi-hop wireless network technology.

Use of legacy and wireless protocols in modern IoT The main goals of this work is implementation of an extension into Inthouse system which will allow remote control of widespread Modbus-enabled devices and creation of an in-house-made simple controller controllable via Bluetooth using simplified JSON RPC protocol and addition of its control support into Inthouse. The next step is to summarize each implementation focusing on its technical complexity and a business potential. This work uncovers interesting details from the implementation and explain causes why such implementation was used in a commercial environment.

With wireless signals, it is possible to send all kind of data through a communication system. Many companies today having problems implementing wireless communication system because of big areas and many obstacles that blocks the wireless signals. Recent releases of mesh network standards that has the main objective to provide a network over a large area. Toyota Material Handling Europe (TMHE) that develops and produce trucks is one company that wants to use this new network topology to get to the next level of communication. TMHE is developing a new communication system between their trucks and the goal is to be independent of Wi-Fi and fixed structures in an industry. The aim is to establish communication through Bluetooth and create a mesh network between the trucks at a site. This kind of communication can create many new possibilities for new features, which can make the daily work easier. The problem with obstacles and interferences is still a problem and TMHE created a thesis to research Bluetooth mesh networks to see if this kind of implementation is suitable for the environments that exists in an industry. This thesis research the architecture of a Bluetooth mesh network and different setups of a network and tests how it stands in an industry with many different surrounding.