Showing papers on "Bluetooth published in 2001"

Dynamic protocol selection and routing of content to mobile devices

Abstract: A method for delivering content to a plurality of mobile devices communicatively coupled to each other via BLUETOOTH technology and participating in a communication network is provided. The content includes a plurality of data types and is delivered from a service provider to at least one of the mobile devices depending on the characteristics of the data and the characteristics of the device. The method includes the steps of associating a user with a global profile having the characteristics of the devices and user attributes, storing the global profile on the service provider; dynamically selecting an optimal communication protocol for transport of the content based on the data type and selecting at least one of the mobile devices being best suited to receive the data type. Thus, the content is routed to one of the devices in accordance with the global profile, data characteristics and prevailing network conditions.

An overview of the Bluetooth wireless technology

Abstract: The Bluetooth/sup TM/ wireless technology is designed as a short-range connectivity solution for personal, portable, and handheld electronic devices. Since May 1998 the Bluetooth SIG has steered the development of the technology through the development of an open industry specification, including both protocols and application scenarios, and a qualification program designed to assure end-user value for Bluetooth products. This article highlights the Bluetooth wireless technology.

Distributed topology construction of Bluetooth personal area networks

Abstract: Wireless ad hoc networks have been a growing area of research. While there has been considerable research on the topic of routing in such networks, the topic of topology creation has not received due attention. This is because almost all ad hoc networks to date have been built on top of a single channel, broadcast based wireless media, such as 802.11 or IR LANs. For such networks the distance relationship between the nodes implicitly (and uniquely) determines the topology of the ad hoc network. Bluetooth is a promising new wireless technology, which enables portable devices to form short-range wireless ad hoc networks and is based on a frequency hopping physical layer. This fact implies that hosts are not able to communicate unless they have previously discovered each other by synchronizing their frequency hopping patterns. Thus, even if all nodes are within direct communication range of each other, only those nodes which are synchronized with the transmitter can hear the transmission. To support any-to-any communication, nodes must be synchronized so that the pairs of nodes (which can communicate with each other) together form a connected graph. Using Bluetooth as an example, this paper first provides deeper insights into the issue to link establishment in frequency hopping wireless systems. It then introduces the Bluetooth topology construction protocol (BTCP), an asynchronous distributed protocol for constructing scatternets which starts with nodes that have no knowledge of their surroundings and terminates with the formation of a connected network satisfying all connectivity constraints posed by the Bluetooth technology. To the best of our knowledge, the work presented in this paper is the first attempt at building Bluetooth scatternets using distributed logic and is quite "practical" in the sense that it can be implemented using the communication primitives offered by the Bluetooth 1.0 specifications.

Wireless private branch exchange (wpbx) and communicating between mobile units and base stations

Abstract: Methods to create a cellular-like communication system, such as a Wireless Private Branch Exchange (WPBX) (123, 124), which includes mobile devices (121, 123) such as a standard cordless phone (handsets), particularly, mobile devices utilizing the Bluetooth short-range wireless communication protocol. The methods provide seamless and reliable handoff of sessions between Base Stations while the mobile device is moving between picocells, by implementing a high-level of synchronization between the Base Stations and the Switch (129). Base Stations of picocells having small coverage areas communicate with the handsets. The communication protocol is divided into a low-level protocol (280, 281) performed by the Base Stations and a high-level protocol (283, 284) performed by the Switch connected to all the Base Stations. The methods support mobile computing or telephony devices and communication protocols, which are not specified to handle handoffs of sessions while moving between Base Stations coverage areas in a data, voice or telephony wireless network.

Bluetrees-scatternet formation to enable Bluetooth-based ad hoc networks

Abstract: Bluetooth is an open specification for short-range wireless communication and networking, mainly intended to be a cable replacement between portable and/or fixed electronic devices. The specification also defines techniques for interconnecting large number of nodes in scatternets, thus enabling the establishment of a mobile ad hoc network (MANET). While several solutions and commercial products have been introduced for one-hop Bluetooth communication, the problem of scatternet formation has not yet been dealt with. This problem concerns the assignment of the roles of master and slave to each node so that the resulting MANET is connected. We introduce two novel protocols for forming connected scatternets. In both cases, the resulting topology is termed a bluetree. In our bluetrees the number of roles each node can assume are limited to two or three (depending on the protocol), thus imposing low slave management overhead. The effectiveness of both protocols in forming MANETs is demonstrated through extensive simulations.

Dual mode wireless data communications

Abstract: A dual mode mobile unit is arranged to communicate in either a first or second data communications standard, such as combined Bluetooth and 80211 operation An interface unit converts received Bluetooth or 80211 format signals into 80211 frame format data signals to be provided to a digital signal processor which is programmed to process signals in either standard The dual mode mobile unit can operate in the 80211 standard to reserve a time interval for Bluetooth activity during which other 80211 units will avoid transmissions to avoid interference

Bluetooth: an enabler for personal area networking

Abstract: We find ourselves today often carrying numerous portable electronic devices, such as notebook computers, mobile phones, PDAs, digital cameras, and mp3/MD/DVD players, used to help and entertain us in our professional as well as private lives. For the most part, these devices are used separately, and their applications do not interact. Imagine, however, if they could interact directly and thus create a network where information may flow seamlessly between the devices-such a network of personal devices is often referred to as a personal area network, or PAN. Moreover, access to the Internet via a (public) wireless LAN access point and/or via a 3G UMTS mobile phone would enable the PAN to be constantly online. The strongest candidate to provide the cheap short-range radio links necessary to enable such networks is the Bluetooth wireless technology. Seen from a networking perspective, a PAN will be expected to have participants, both of its "own" devices and "guest" devices from other PANs, continuously moving in and out of its coverage. To cope with this volatile nature of the network, the concept of ad hoc networking may be applied to create robust and flexible connectivity. A major technical step is taken when the Bluetooth piconet network architecture, a strict star topology, is extended into a scatternet architecture, where piconets are interconnected. A consequence of creating scatternet-based PANs is that some nodes will form gateways between piconets, and these gateways must be capable of time sharing their presence In each piconet of which they are members. While the Bluetooth standard defines the gateway nodes, the actual mechanisms and algorithms that accomplish the interpiconet scheduling (IPS) are left rather open. Given the lack of research literature in the subject, an overall architecture for handling scheduling in a scatternet is presented. A family of feasible IPS algorithms, referred to as rendezvous point algorithms, is also introduced and discussed.

Wi-Fi (802.11b) and Bluetooth: enabling coexistence

Abstract: This article provides an introduction to issues of coexistence between Bluetooth and Wi-Fi/sup TM/ (IEEE 802.11b), with particular attention to scenarios requiring simultaneous operation, or Sim-OP/sup TM/, of both systems in very close proximity. The article explains basic interference mechanisms and quantifies their impact through both actual measurements and simulation. We have developed a detailed simulator that fully models behavior of the physical layer (PHY) and media access control (MAC) of both Bluetooth and 802.11b; it is used to expand the analysis and project the mutual impact of collocated Bluetooth and 802.11b systems across a number of geometries, system parameter settings, and design choices, complementing efforts within the IEEE 802.15.2 Task Group, which are also discussed. The article concludes with a discussion of techniques with the potential to greatly improve the performance of collocated Bluetooth and Wi-Fi systems. A key result of this investigation is that while performance of both systems can degrade when they are collocated, a number of techniques can be employed to virtually eliminate the problems.

Resource proxy for mobile wireless electronic devices

Abstract: A method and system supporting location based services for a mobile electronic device that supports multiple wireless communication technologies. The mobile device contains a resource proxy for dynamically storing a set of resources that are available to the electronic device and that are location specific, e.g., accessible via a point that is near the electronic device. The resource proxy contains a resource table recording the available resources and a gateway table indicating a pathway for reaching the data. The resource proxy definitions are technology independent with respect to the communication mechanisms required to obtain the data. Resources are added to the resource proxy via a resource discovery mechanism automatically performed by the mobile device. Multiple network gateways can be defined and each is responsible for requesting and retrieving information for the resource proxy. Network gateways are coupled to network interfaces which provide the logic required to perform wireless communication using particular communication mechanisms, e.g., Bluetooth or wireless LAN, etc. Applications interface with the resource proxy using technology independent commands in order to obtain information from the available resources recorded in the resource proxy. Using the system of the invention, available resources for a particular location are collected via a single process/database on the mobile device and presented to the applications in a uniform way.

Optimization scheme for mobile users performing vertical handoffs between IEEE 802.11 and GPRS/EDGE networks

Abstract: The next generation wireless networks are characterised by anywhere, anytime connectivity, enhanced data services and higher data rates to enduser. New technologies such as IEEE 802.11 WLAN, Bluetooth, HIPERLAN/2, GPRS/EDGE, cdma2000 and WCDMA aim to achieve this. To facilitate new services, and make them flexible and bandwidth efficient, vertical roaming of mobile nodes is a tempting possibility for operators. Benchmarks and metrics are needed to assess these issues. The need for qualitative and quantitative results for these parameters in a real time situation is critical. One such scenario is the effect on the network performance by means of effective throughput and handoff latency perceived by the mobile user, with increasing number of active users or network load. This paper presents simulation results for mean throughput and handoff delay obtained in vertical handoff and horizontal handoff in IEEE 802.11 and GPRS/EDGE networks. An optimization scheme for mobile users performing vertical handoffs is presented with analysis.

Bluetooth Revealed: The Insider's Guide to an Open Specification for Global Wireless Communications

Abstract: The authoritative guide to Bluetooth! From two contributors to the Bluetooth specification!For users, the new Bluetooth wireless standard will cut through the complexity of wireless communications, enabling devices to communicate seamlessly. Bluetooth Revealed offers the first insider's view of the Bluetooth standards: crucial information and insight professionals need to start implementing Bluetooth solutions -- now. Written by leaders of the Bluetooth community, it presents the entire specification in unprecedented depth: its goals, scope, structure, interrelationships, and applications. Coverage includes: Design challenges: 2.4 GHz spectrum characteristics, power consumption, global standardization, and other key issues Usage models: cordless computing, advanced headsets, file transfer/sync, dial-up networking, conferencing, hidden computing, and more The entire Bluetooth protocol stack: radio, baseband, and software layers; hardware and interfaces; and Link Manager and Logical Link Control and Adaptation Protocol (L2CAP) Bluetooth profiles: generic, telephony, networking, serial, and object exchangeBluetooth Revealed previews Bluetooth's future, including next-generation vertical and horizontal applications, and introduces today's resources for Bluetooth development, including silicon and developer's kits, as well as legacy product enablers. If you're intending to build, deploy, or market Bluetooth solutions, start right here.

Hybrid Bluetooth/RFID based real time location tracking

Abstract: Devices having either wireless data communication capability or RFID tags can be located using dual function fixed devices which are distributed throughout a facility. The devices will identify those units with which they are communicating using a wireless radio data communications protocol and also identify items within the local area using RFID tags on the units.

System and method for distributing digital content in a common carrier environment

Abstract: A system and method for distributing digital content on-demand in a common carrier environment, such as an airplane, are disclosed. The present invention employs a combination of low power RF (e.g., WLAN/Bluetooth) and digital data broadcast (e.g., DVB-T) technology to distribute digital content to passengers in an airplane cabin. In an advantageous embodiment, a mobile multimedia terminal (or, alternatively, a fixed seat-back terminal), with a WLAN or Bluetooth link to a content server aboard the plane is used by a passenger to request digital content such as movies, music, games, etc. In response, the server transmits the requested content to the passenger's device via a DVB-T connection. The elimination of a wired connection for each of, for example, 400+ passengers in a Boeing 747, decreases the overall weight of the system and thus reduces fuel costs. A mechanism is also disclosed for quickly updating content in the airplane's server via a DVB-T connection while the plane is at a gate receiving flight and operational data for its next flight.

Efficient polling schemes for Bluetooth picocells

Abstract: Bluetooth is a new low-cost wireless technology that is going to play an important role in communications among small electronic devices and the access to wired networking infrastructure. Bluetooth stations that communicate directly form a piconet. In a piconet one station has the role of master and the others are slaves. The access to the medium is based on a TDD (time division duplexing) scheme controlled by the master. The master sends packets to slaves in even-numbered slots triggering a transmission from slaves in the subsequent slot. Slaves are allowed to send packets only in response to a master packet. The way in which the master schedules packets transmission to slaves or polls them determines system performance. We consider the problem of designing an efficient and simple polling and scheduling scheme for Bluetooth. We propose some practical schemes and compare their performance with some ideal schemes derived from known results for polling systems.

Intra-piconet location determination and tomography

Abstract: A technique for intra-piconet location determination and tomography is described. This technique uses received signal strength indicator (RSSI) values in conjunction with transmitted power levels to determine the relative location of each device within a small network employing frequency hopped spread spectrum transmission. In addition to the location determination properties of the invention, the geometry of the devices in the network, as well as the path loss information between pairs of devices, may be used to infer the location of absorbers and reflectors within the piconet. This absorption and reflection information may be used in creating the piconet tomography. The approach described in this specification may be applied in conjunction with the Bluetooth wireless Personal Area Network (PAN) specification to determine device locations, mitigate the effects of multi-path, and perform indoor location and security functions, and other application functions requiring cost-effective location determination.

Network compatible RF wireless link for medical device data management

Abstract: A network compatible RF Wireless Link for Medical Device Data Management includes apparatus for establishing a communication link between an IMD, a patient-worn device, and a remote monitoring station while at the same time minimizing device current drain. The minimal current drain is achieved by scheduling periodic interrogation of the data collected by the IMDs for subsequent transmission to a remote location. Generally, the communication system is implemented to transmit data preferably telemetered from the IMD to a patient-worn device. The data from the patient-worn device is transmitted to a transceiver that sends the data to a remote information network. The patient-worn device may be equipped with a Bluetooth (BT) or Home communication system. The transceiver is preferably similarly equipped with BT or Home RF technology having a plurality of nodes. In one aspect of the invention, the patient-worn device would transmit data to the transceiver, which may be connected to a phone line, cellular phone, satellite communication systems, telemetry or equivalent wireless data communication system. The system provides patient mobility while enabling data transmission and interrogation of one or more implanted medical devices in the patient.

Enhancing performance of asynchronous data traffic over the Bluetooth wireless ad-hoc network

Abstract: Emerging technologies such as Bluetooth are expected to become a ubiquitous solution for providing short range, low power, low cost, pico-cellular wireless connectivity. Bluetooth is a master driven time division duplex (TDD) system that supports an asynchronous channel for data traffic as well as synchronous channels for voice traffic. Data applications running over Bluetooth such as http, ftp and real audio will need transport layer protocols such as TCP and UDP to send packets over the wireless links. In this paper we study several schemes designed to improve the performance of asynchronous data traffic over a Bluetooth piconet that supports multiple active slaves. We propose and compare a number of segmentation and reassembly policies and MAC scheduling algorithms with a view towards enhancing the performance of transport layer sessions. We investigate the effect of different FEC and ARQ schemes at the baseband level, using a two-state Markov channel model for the Bluetooth RF link. We also study how the presence of circuit-switched voice impacts the performance of data traffic.

Bluetooth: technology for short-range wireless apps

Abstract: In 1998, five major companies (Ericsson, Nokia, IBM, Toshiba and Intel) formed a group to create a license-free technology for universal wireless connectivity in the handheld market. The result is Bluetooth, a technology named after a 10th-Century king who brought warring Viking tribes under a common rule. The Bluetooth specifications (currently in version 1.1) define a radiofrequency (RF) wireless communication interface and the associated set of communication protocols and usage profiles. The link speed, communication range and transmission power level for Bluetooth were chosen to support low-cost, power-efficient, single-chip implementations of the current technology. In fact, Bluetooth is the first attempt at making a single-chip radio that can operate in the 2.4-GHz ISM (industrial, scientific and medical) RF band. While most early Bluetooth solutions are dual-chip, vendors have recently announced single-chip versions as well. In this overview of the technology, I first describe the lower layers of the Bluetooth protocol stack. I also briefly describe its service discovery protocol and, finally, how the layers of the protocol stack fit together from an application's point of view.

Security apparatus and method during BLUETOOTH pairing

Abstract: A BLUETOOTH device is provided wherein the output RF transmission power level during pairing is purposefully reduced from otherwise conventional or normal communication levels to a low power level, greatly reducing the range of possible interception. Security can be improved even more by further reducing the transmit power even below that defined for a class 2 radio to an extremely low power level. After the link keys have been passed and/or other pairing processes, the BLUETOOTH devices may safely return to normal power levels to continue communications. Thus, a BLUETOOTH device is forced to radiate in low power when pairing is performed. The user(s) may be directed to co-locate the pairing BLUETOOTH devices in any appropriate manner, e.g., through a display prompt on the BLUETOOTH device. In an alternative embodiment, a BLUETOOTH device may be required to transmit data keys (e.g., a link key) and/or other pairing operations over a temporary wired connection (or temporary line-of-sight or near line-of-sight connection such as infrared) to another BLUETOOTH device.

Method for managing network when master disappears

Abstract: A method for managing a network in which Bluetooth equipped devices are linked together when the network master cannot serve as a master. During normal operation, the network master updates the backup master rank information when the network master disappears, in a predetermined cycle, according to link information, such as received signal strength indication (RSSI) or link quality, transmitted from the Bluetooth equipped devices serving as a slave. When power of the network master is exhausted, or when the network master leaves the network operating region, a new master is selected from the remaining slaves according to the backup master rank information, thereby reconfiguring a network around the new network master. The method enables proper designation of a new master when a preexisting network master leaves the network operating region, thereby increasing a probability of holding connection throughout the network.

Unified passcode pairing of piconet devices

Abstract: The present invention relates to an application layer function outside the BLUETOOTH protocol which associates a BLUETOOTH unique address, i.e., the 48-bit unique BD_ADDR address, with a short passcode or PIN which is associated with a particular type of BLUETOOTH device in a particular piconet. The passcode or PIN can be pre-determined by the manufacturer of the BLUETOOTH device, or can be input and defined by the user. Upon installation in a piconet, in one embodiment shown and described with reference to FIGS. 1 and 2 , a user can be asked to manually input a particular passcode or PIN into a relevant piconet device, and an inquiry can be broadcast to all communicating piconet devices and only those other piconet devices having a matching passcode or PIN associated therewith can automatically forward their respective 48-bit unique BD_ADDR addresses to the inquiring piconet device. Alternatively, a user can inquire and be provided with a list of available passcodes or PINs already established by other devices in the piconet, and select a particular passcode or PIN associated with one or more other piconet devices. The passcode or personal identification number (PIN) may be input upon electronic device setup (e.g., a four character code). The passcode or PIN may be numeric, text, or alphanumeric.

Apparatus, and associated method, for facilitating authentication of communication stations in a mobile communication system

Abstract: Apparatus, and an associated method, facilitates authentication of at least a portion of a Bluetooth-based, or other, communication system by a mobile terminal. A manner is provided by which to provide to the network portion of the communication system unique identifiers which identify the Bluetooth transceiver circuitry of the mobile terminal. Once provided to the network portion, authentication procedures by which to authenticate the network portion are carried out.

Wireless Security: Models, Threats, and Solutions

Abstract: Table of contents Chapter 1 Why is Wireless Different? Chapter 2 Wireless Information Warfare Chapter 3 Telephone System Vulnerabilities Chapter 4 Satellite Communications Chapter 5 Cryptographic Security Chapter 6 Speech Cryptology Chapter 7 The Wireless Local Area Network (WLAN) Chapter 8 Wireless Application Protocol (WAP) Chapter 9 Wireless Transport Layer Security (WTLS) Chapter 10 Bluetooth Chapter 11 Voice Over Internet Protocol Chapter 12 Hardware Perspectives for End-to-End Security (E2E) in Wireless Applications Chapter 13 Optimizing Wireless Security with FPGAs and ASICs Bibliography Index

Performance of a new Bluetooth scatternet formation protocol

Abstract: A Bluetooth ad hoc network can be formed by interconnecting piconets into scatternets. The constraints and properties of Bluetooth scatternets present special challegnes in forming an ad hoc network efficiently. In this paper, we evaluate the performance of a new randomized distributed Bluetooth scatternet formation protocol. Our simulations validate the theoretical results that our scatternet formation protocol runs in O(log n) time and sends O(n) messages. The scatternets formed have the following properties: 1) any device is a member of at most two piconets, and 2) the number of piconets is close to be optimal. These properties can avoid overloading of any single device and lead to low interference between piconets. In addition, the simulations show that the scatternets formed have O(log n) diameter. As an essential part of the scatternet formation protocol, we study the problem of device discovery: establishing multiple connecitons with many masters and slaves in parallel. We investigate the collision rate and time requirement of the inquiry and page processes. Deducing from the simulation results of scatternet formation and device discovery, we can verify that the total number of packets sent is O(n) and demonstrate that the maximum number of packets sent by any single device is O(log n). At last, we give estimates of the total time requirement of the protocol and suggest further improvements

Interference of bluetooth and IEEE 802.11: simulation modeling and performance evaluation

Abstract: The emergence of several radio technologies such as Bluetooth, and IEEE 802.11 operating in the 2.4 GHz unlicensed ISM frequency band may lead to signal interference and result in significant performance degradation when devices are co-located in the same environment. The main goal of this paper is to present a simulation environment for modeling interference based on detailed MAC and PHY models. This framework is then used to evaluate the impact of interference on the performance of Bluetooth and IEEE 802.11. We use several simulation scenarios and measure performance in terms of packet loss, residual number of errors, and access delay.

A Bluetooth scatternet formation algorithm

Abstract: A Bluetooth ad hoc network can be formed by interconnecting piconets into scatternets. The constraints and properties of Bluetooth scatternets present special challenges in forming an ad hoc network efficiently. We present and analyse a new randomized distributed algorithm for Bluetooth scatternet formation. We prove that our algorithm achieves O(log n) time complexity and O(n) message complexity. We show that: (1) in the scatternet formed by our algorithm, any device is a member of at most two piconets; (2) the number of piconets is close to being minimal.

WLAN and WPAN coexistence in UL band

Abstract: Wireless local- and personal-area networks provide complimentary services in the same unlicensed (UL) radio frequency band of operation. As the mutual benefits of utilizing these services become increasingly apparent, the likelihood of mutual interference may also increase. A method was developed for examining wireless services coexistence in order to evaluate the impact that interference may have on network performance. The methodology for the analysis was centered on deriving a closed-form solution for the probability of collision Pr[C] in terms of the network and radio propagation parameters. In addition, a set of measures of performance was derived based on Pr[C]. In this fashion, the network performance was investigated in regards to the presence of interference. The approach was then illustrated by examining the coexistence between 802.11b and Bluetooth UL band wireless services and summarizing the impact on network performance.

Interference between Bluetooth networks-upper bound on the packet error rate

Abstract: This paper presents a probabilistic treatment of the performance of a Bluetooth piconet under cochannel interference from other Bluetooth piconets. An upper bound on the packet error rate of a link is given, as well as a lower bound on the aggregated throughput of n collocated piconets.

Modular communication and control system and method

Abstract: A system and method for detecting and monitoring at least one event or condition of interest. The system comprises a sensor and a wireless transmitter and receiver (150). Upon detection of an event of interest, the sensor communicates that information to the transmitter for communication to the receiver. A module with a sensor to indicate the position of a door coupled to a door opener. The module (200) is compatible with a wireless communication protocol and operates over both a long range, such as is used with a cellular telephone, and a short range, such as is used with BLUETOOTH. A door position sensor coupled to the module (200) provides information to the user over a wireless communication channel. In one embodiment, information from an additional door position sensor is wirelessly transmitted. In one embodiment, an audio transducer coupled to the module responds to voice commands to operate the door opener.

Wireless deployment of bluetooth access points using a distributed antenna architecture

Abstract: The present invention provides a wireless communications system, in which a distributed antenna system (DAS) and one or more master Bluetooth access point modules are employed to extend the range of and wirelessly deploy Bluetooth access points (BTAPs) in a scalable and versatile manner. A variety of wireless personal area networks (WPANs) are further created, to support multiple slave Bluetooth devices. As such, the present invention provides a simplified and easily scalable Bluetooth coverage infrastructure, allows pooling the resources of Bluetooth access points for best performance/cost ratio and dynamic RF routing/filtering in capacity management, and simplifies the provisioning in the system.