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Multibeam antenna arrays (MBAAs) have the capability to improve the capacity of a wireless network by facilitating simultaneous transmissions to multiple users. However, in practical deployments of wireless personal or local area networks (WPANs/WLANs) where piconet coordinators or access points (PNCs/APs) are deployed with MBAAs, it is quite likely to observe non-uniform node densities in various regions. To optimally utilize MBAAs in such scenarios, concurrent transmission scheduling in WPANs/WLANs is formulated as a multi-objective optimization problem. Then, a practical heuristic transmission scheduler that aims to maximize the number of concurrent communications by dynamically configuring the directions of beams is proposed. In addition, a service tag based fair scheduler is also proposed to achieve weighted fairness in WPANs/WLANs with MBAAs. Our results show that the performance improvements provided by the proposed heuristic scheduler are higher for antennas with lower beamwidths, and as the non-uniformity in the network increases, the traffic supported in the network increases in the range 24–41%, compared to the existing methods. The proposed service tag based scheduler can further improve the network throughput and achieve better fairness at the cost of a few beam direction reconfigurations, as compared to the existing methods and our heuristic scheduler.

Currently, research on Bluetooth-based mobile ad hoc networks (hereinafter referred to as Bluetooth MANETs) is being conducted. As an application of Bluetooth MANETs, a grass-root disaster information propagation system has been studied for the purpose of information distribution following disasters. Bluetooth standards include Classic Bluetooth (hereinafter referred to as Classic), which can transfer relatively large data packets, and Bluetooth Low Energy (hereinafter referred to as BLE), which can work with relatively low power consumption. So far, a rapid connection establishment method that combines Classic and BLE in a complementary manner (hereinafter referred to as the existing method) and the flooding-based data packet transfer method with delay- and disruption- tolerance have been proposed. In the existing method, a Bluetooth MANET is constructed by connecting multiple piconets, which consist of one master and multiple slaves. In the existing method, loops are easily formed in a Bluetooth MANET due to the establishment of connections between slave terminals in a piconet in an environment with high terminal density. Therefore, when the flooding-based data packet transfer method is used in the existing method, the amount of data packets increases and the processing load on the terminals increases. In this paper, we proposed a method to reduce the number of loops by controlling the connection establishment between slave terminals in a piconet for Bluetooth MANETs (hereinafter referred to as our proposed method). In addition, we have evaluated the effect of our proposed method on data packet transfer through simulation experiments. As a result, we confirmed that our proposed method can reduce the number of loops and the number of data packet transmissions while maintaining the time to complete the data packet dissemination at the same level as the existing method.

An ultra-dense millimetre wave (mmWave) access network operating on IEEE 802.15.3c based simultaneously operated piconet (SOP) architecture offers an effective way to operate high data-rate IoT-networks while overcoming the challenges of beam-blockage and high propagation loss which characterize these systems. The SOP architecture permits coexistence of multiple mmWave piconets by allowing a piconet controller (PNC) to share its channel time with multiple PNCs, using periodically updated private channel time allocations (p-CTAs). However, due to beam blockage, the p-CTA demands within the piconets change dynamically and often cause a mismatch between the demanded and the assigned p-CTAs leading to suboptimal resource allocation and wastage of network resources. To overcome these problems, this letter proposes a QoS aware risk-sensitive approach for p-CTA assignment. It uses multiple QoS parameters as performance metrics and employs the portfolio allocation theory to dynamically determine the optimal p-CTA distribution. By judiciously allocating p-CTAs over a portfolio of SOPs, the proposed approach minimizes the risk of p-CTA mismatch for each piconet and mitigates the wastage of network resources.

This paper presents the performance analysis of Bluetooth Low Energy (BLE) IEEE 802.15.1 standard in the piconet topology networks. The performance of the BLE network is analyzed in terms of connection interval (CI) and the number of slaves (NS) by using OMNET++ (v4.6) simulator. In the performance investigation process Data Length Extension (DLE) features is used with an application payload size of 60 bytes in order to achieve the best performance in a BLE (P2P) network. The modeled networks and due to the nature of short-range BLE wireless communication show a good matching between analytical and simulation results. For Single-Slave (or one like) piconet the obtained maximum simulation throughput is 478.7 kbps when a connection interval of (7.5) ms is used.

In thispaper we investigate the effect of different beaconing strategies for wirelesspersonal area networks. Beacons are used by network coordinators to indicatethe existence of the networks. A long beacon range protects the devices frominterference of neighboring networks. Nevertheless increased protection reducesnumber of possible networks in an area and increases number of devices pernetwork. We investigate the effect of the beacon range in terms of throughputin IEEE 802.15.3c based 60 GHz WPANs. Long range beacons enable %20 more, whileallowing %40 less networks. throughput In addition we are suggesting a flexiblebeacon system which can adjust the piconet protection. In certain situations,flexible beaconing both increase the troughput of protected link and the total numberof networks in the area., Bumakalede farklı kılavuz işaret stratejilerinin kablosuz kişisel ağların başarımınaolan etkisini incelenmiştir. Ağ koordinatörleri kılavuz işaretleri, ağınvarlığını belirtmek için kullanırlar. Eğer kılavuz işaretinin menzili uzunsa,komşu ağlarda bulunan cihazlardan daha az girişim alınır. Fakat bu durum bellibir alanda sınırlı sayıda ağa izin verip ağ başına düşen cihaz sayısınıarttırır. Kılavuz işaretinin ağ kapasitesine olan etkisini incelemek için IEEE802.15.3c tabanlı 60 GHz kişisel ağları seçtik. Uzun haberleşme menzili olankılavuzlar girişim altında olan cihazlara yaklaşık %20 daha fazla kapasitesağlamakla beraber çok daha az sayıda ağa izin vermektedir. Ayrıca bu çalışmadakablosuz ağın girişimden korunması için esnek bir kılavuz işaret sistemiönerilmiştir. Esnek kılavuz işaretleri hem girişime dayanıklılık sağlarken hemde toplam kablosuz ağ sayısını yüksek tutmaktadır.

Bluetooth wireless technology is a robust short-range communications system designed for low power (10 meter range) and low cost. It operates in the 2.4 GHz Industrial Scientific Medical (ISM) band and it employs two techniques for minimizing interference: a frequency hopping scheme which nominally splits the 2.400 - 2.485 GHz band in 79 frequency channels and a time division duplex (TDD) scheme which is used to switch to a new frequency channel on 625 μs boundaries. During normal operation a Bluetooth device will be active on a different frequency channel every 625 μs, thus minimizing the chances of continuous interference impacting the performance of the system. The smallest unit of a Bluetooth network is called a piconet, and can have a maximum of eight nodes. Bluetooth devices must assume one of two roles within a piconet, master or slave, where the master governs quality of service and the frequency hopping schedule within the piconet and the slave follows the master’s schedule. A piconet must have a single master and up to 7 active slaves. By allowing devices to have roles in multiple piconets through time multiplexing, i.e. slave/slave or master/slave, the Bluetooth technology allows for interconnecting multiple piconets into larger networks called scatternets. The Bluetooth technology is explored in the context of enabling ad-hoc networks. The Bluetooth specification provides flexibility in the scatternet formation protocol, outlining only the mechanisms necessary for future protocol implementations. A new protocol for scatternet formation and maintenance - mscat - is presented and its performance is evaluated using a Bluetooth simulator. The free variables manipulated in this study include device activity and the probabilities of devices performing discovery procedures. The relationship between the role a device has in the scatternet and it’s probability of performing discovery was examined and related to the scatternet topology formed. The results show that mscat creates dense network topologies for networks of 30, 50 and 70 nodes. The mscat protocol results in approximately a 33% increase in slaves/piconet and a reduction of approximately 12.5% of average roles/node. For 50 node scenarios the set of parameters which creates the best determined outcome is unconnected node inquiry probability (UP) = 10%, master node inquiry probability (MP) = 80% and slave inquiry probability (SP) = 40%. The mscat protocol extends the Bluetooth specification for formation and maintenance of scatternets in an ad-hoc network.

In this paper, we developed and integrated a realtime emotion recognition system using an AI system-on-chip design. The emotion recognition platform combined three different physiological signals, Electroencephalogram (EEG), electrocardiogram (ECG), and photoplethysmogram (PPG) as the classification resources. A 3-to-1 Bluetooth piconet was deployed to transmit all physiological signals on a single platform access point and to make use of low power wireless technologies. The system then integrated an AI computing chip with a convolution neural network (CNN) structure to classify three emotions, happiness, anger, and sadness. The average accuracy for a subject-independent classification reached 72.66%. The proposed system was integrated with the RISC-V processor and AI SOC to implement real-time monitoring and classification on edge.

In this paper, we developed and integrated an AI-edge emotion recognition platform using multiple wearable physiological signals sensors: Electroencephalogram (EEG), electrocardiogram (ECG), and photoplethysmogram (PPG) sensors. The emotion recognition platform used two combined machine learning approaches based on two systems input and preprocessing: An EEG-based emotion recognition system and an ECG/PPG-based system. The EEG-based system is a convolution neural network (CNN) that classifies three emotions, happiness, anger and sadness. The inputs of the CNN are extracted from the EEG signals using short-time Fourier transform (STFT), and the average accuracy for a subject-independent classification reached 76.94%. The ECG/PPG-based system used a similar CNN with an extracted features vector as input. The subject-dependent ECG/PPG classification system reached an average accuracy of 76.8%. The proposed system was integrated using the RISC-V processor and FPGA platforms to implement realtime monitoring and classification on edge. A 3-to-1 Bluetooth piconet was deployed to transmit all physiological signals on a single platform access point and to make use of low power wireless technologies.

Consider a wireless network consisting of a set of wireless nodes and a set of communication links, where each communication link corresponds to a pair of nodes that are within communication radius of each other. Under the primary interference model, two communication links cannot be active at the same time if they are incident to a common node. This model of interference arises in Bluetooth networks, where transmissions between a master node and slave nodes in a piconet are scheduled by time-division duplexing, and in CDMA systems when each node is equipped with a single transceiver. Each communication link has a certain minimum bandwidth quality-of-service requirement. The admission control problem is to determine whether the network has sufficient resources to satisfy the bandwidth requirements. In this work, distributed algorithms are proposed for this admission control problem, and performance guarantees of these distributed algorithms are given. If each node has knowledge of a certain global parameter, then a distributed algorithm for flow admission control is given which has the same performance as an optimal, centralized algorithm, i.e. the distributed algorithm gives a condition that is both necessary and sufficient for a set of flow rates to be feasible.

Bluetooth Classic (BT) remains the de facto connectivity technology in car stereo systems, wireless headsets, laptops, and a plethora of wearables, especially for applications that require high data rates, such as audio streaming, voice calling, tethering, etc. Unlike in Bluetooth Low Energy (BLE), where address randomization is a feature available to manufactures, BT addresses are not randomized because they are largely believed to be immune to tracking attacks. We analyze the design of BT and devise a robust de-anonymization technique that hinges on the apparently benign information leaking from frame encoding, to infer a piconet’s clock, hopping sequence, and ultimately the Upper Address Part (UAP) of the master device’s physical address, which are never exchanged in clear. Used together with the Lower Address Part (LAP), which is present in all frames transmitted, this enables tracking of the piconet master, thereby debunking the privacy guarantees of BT. We validate this attack by developing the first Software-defined Radio (SDR) based sniffer that allows full BT spectrum analysis (79 MHz) and implements the proposed de-anonymization technique. We study the feasibility of privacy attacks with multiple testbeds, considering different numbers of devices, traffic regimes, and communication ranges. We demonstrate that it is possible to track BT devices up to 85 meters from the sniffer, and achieve more than 80% device identification accuracy within less than 1 second of sniffing and 100% detection within less than 4 seconds. Lastly, we study the identified privacy attack in the wild, capturing BT traffic at a road junction over 5 days, demonstrating that our system can re-identify hundreds of users and infer their commuting patterns.

We tackle the problem of minimizing the maximum expected delivery time of all transmission pairs in 60 GHz mmWave networks. The network is dual-hop with multiple transmitter-receiver pairs, relays, and a centralized controller (termed PicoNet coordinator). We jointly optimize relay and link selection for the transmitter–receiver pairs to minimize delivery time, while the reflected non-line-of-sight transmission links are exploited to get around obstacles. To reduce computational complexity, we develop a decomposition principle to transform the joint-optimization problem into a link selection subproblem and a relay assignment subproblem when there are a sufficient amount of relays. A tight performance bound for the proposed algorithm is proved. We also develop a heuristic scheme to handle the case when there are no enough relays. The superior performance of our proposed algorithms is validated with extensive simulations and comparisons with benchmark schemes.

The introduction of new key features into the core specification of Bluetooth Low Energy (BLE) increased its potentialities, thus paving the way to the development of new networking paradigms. The ability for a single node to participate in more than a piconet and to assume both the role of master and slave makes it possible the formation of multi-hop networks that can be used in several emerging application scenarios. Additionally, the inherent low power consumption at the cost of contained throughput makes this technology appealing for Internet of Things (IoT), where power memory and capacity constrained devices exchange messages at relatively low data rates. In this paper, we devise a two layers BLE mesh-based networking paradigm obtained by generalizing Android BE-MESH for hardware-independent sensor networks. Each node enforces a plug-and-play architecture which makes it able to autonomously switch between client and server role, discover and connect to existing scatternets and relay messages through them, making the network able to extend and self re-organize in a distributed fashion. To have our implementation ready for IoT systems we based it on the ESP32 off-the-shelf board. We describe both the implemented functions as well as some practical results proving the effectiveness of the framework in some tested configurations.

The shared superframe multihop nature of wireless personal area networks (WPAN s) encounters fundamental challenges to the design of effective and optimal resource allocation algorithms with respect to resource utilization and fairness across different network devices. In this paper, we propose a distributed optimization framework for resource allocation scheme for IEEE 802.15.5 hop-2 for fairly sharing the channel time resources granted by the reference Mesh Piconet Coordinator (MPNC) to the hop-1 MNPC among hop-2 devices. A NUM based optimization approach is proposed for optimal resource allocation with differentiation between real-time (RT) and non-real time (NRT) devices. Simulation results for studying satisfaction and fairness indexes are conducted.

Bluetooth and IEEE 802.11 (Wi-Fi) are two of the most popular communication standards that define physical and MAC layers for wireless transmissions and operate on 2.4GHz industrial scientific medical (ISM) band. To avoid the rich interference existed in ISM band, Bluetooth adopts a time-slotted frequency-hopping spread-spectrum scheme, preventing the Bluetooth device communication from being interfered for a long time on specific channel. However, the coexistence of Bluetooth and Wi-Fi in the neighborhood degrades the performance of both networks because the two wireless technologies cannot negotiate with each other. To improve the throughput of a given piconet, this paper presents two interference aware approaches. First, an interference aware piconet establishment mechanism, called IAPE, is proposed to consider the frequencies occupied by Wi-Fi and then minimize the interference from Wi-Fi transmissions, when Bluetooth and Wi-Fi coexist in the same space. To further improve the throughput of the constructed piconet, an interference aware piconet restructuring mechanism, called IAPR, is proposed. Performance study reveals that the proposed IAPE and IAPR approaches further reduce the interference between Bluetooth and Wi-Fi and thereby save the energy of Bluetooth device, improving the throughput of Bluetooth personal area networks (PANs).

Limited resources and network dynamicity are challenging issues in Bluetooth networks. Therefore, scatternet formation improvement and efficient routing algorithms are required that can efficiently construct a short route between a source and destination. As of today, many protocols have been proposed, mostly researchers focusing on simplicity and reliability, but only few of them fulfill the Bluetooth scatternet scenario. Therefore, it opens new doors for scatternet formation and inter-piconet routing for the Bluetooth scatternet. This paper presents a review of Bluetooth routing and scatternet formation protocols for inter-piconet communication. First, Bluetooth operation is explained followed by important applications and topologies are discussed. Then, inter-piconet routing and network formation protocols are critically analyzed. Finally, Bluetooth problems and open research issues are highlighted.

Model for reducing energy consumption in wireless sensor network is presented. Model of reducing the power consumption for node of wireless sensor network in embedded control systems. The operation of the wireless sensor network node is analyzed. Different models was analyzed for reducing energy consumption by node in wireless sensor network. The combination of a large number of nodes into a network, the requirements for minimizing the energy consumption of nodes and the network as a whole lead to the need for additional structural solutions when creating wireless sensor networks. The most important of these is network clustering, which also implies constant rotation of the cluster head node during the network life cycle. The proposed network structure with cluster unification in a piconet provides an advantage that is inherent in the hierarchical method of building wireless sensor networks.

Bluetooth is the de facto for IoT communication and the most prominent communication technology for smart homes and smart cities. Despite its design for small devices, e.g., computer mice, it evolved to support a wide range of applications. However, it still carries limitations like low data rate, inefficient device discovery, limited range, and interference. Addressing these aspects is impossible for the research community as Bluetooth core specifications are locked on hardware chips. In this work, we propose BLINK, a modified version on Bluetooth v4.0 that supports multicast communication elevating the data rate within a Bluetooth piconet. First, we provide an open source Bluetooth stack implementation to the research community. Second, we introduce multicasting to Bluetooth piconets through extending the set of packet formats. Third, we customize the Bluetooth timing to schedule an interference free communication of multicast streams between piconet devices. Fourth, we evaluate BLINK on a testbed of 4 devices and show that data exchange rate was enhanced by 1.5–3 folds.

This paper introduces two distributed Bluetooth scatternet formation (BSF) algorithms, called $\mathtt{BSFWAVVY(MSF)}$ and $\mathtt{BSFWAVVY(ODL)}$ . The first algorithm forms scatternets that does not contain master–slave (MS) bridges (MS-free scatternets), whereas the second algorithm forms scatternets in which each piconet has at most $k$ slaves (outdegree-limited scatternets). The motivation is that MS-freeness and outdegree limitation are the two properties that significantly improve the quality of the scatternets. However, and contrary to the existing BSF algorithms, our algorithms consider these properties under pessimistic environments modeled as arbitrary networks (i.e., no assumptions are made on the underlying network topology). We give two lower bounds that prove the asymptotic optimality of our algorithms with respect to time complexity and message complexity. We also show that the problem of forming MS-free and outdegree-limited scatternets at the same time is ${\sf{NP}}$ - ${\sf{COMPLETE}}$ . We introduce a time-efficient implementation of $\mathtt{BSFWAVVY(MSF)}$ and $\mathtt{BSFWAVVY(ODL)}$ that exploits unique characteristics of Bluetooth networks. Simulation experiments show that our algorithms have short execution time relative to major BSF algorithms and it outperforms other major algorithms with respect to various performance metrics.

Contents of the beginning of the personal wireless communications and original Bluetooth version are presented and the classes of the power also. Bluetooth technology forms its network from eight devices, this network is called Piconet. Every piconet contains from one device acts as a master and seven device act as slave. There are two types of physical connections, the ACL and SCO connection for voice communications. This chapter also presents the different Bluetooth protocols. The Bluetooth technology can be considered adaptive packets technology; there are different packets format can be employed for user data transmission. The different packets are introduced in this chapter.

In order to raise the efficiency of on-site live detection, we proposed a new study of live detection data management system which based piconet and Electric Power System Secure Access Platform(EPSSAP). Piconet of comprehensive multi professional testing equipments with Bluetooth technology is established to wireless acquisite field testing data. Using mobile APN secure access technology, secure communication between the intranet information system and PC power system is realized. Application of the platform will provide basis for a unified multiple data acquisition system, extend functions of intranet information system, such as data storage, information processing regulate the process of on-site live detection work and improve the efficiency of the use of live detection data.

The purpose of this research is to develop Piconet Pervasive system from previous research that analyzed security system and optimized system performance of video streaming rate data transmission over Bluetooth Piconet Pervasive network, using Symbian OS on the client side. This research was still running on client side Symbian platform by using point-topoint topology. Based on previous research, in this study, Piconet pervasive system is developed. The system runs on Android and Symbian operating system on the client side, using point-tomultipoint topology. This research is a quantitative research with experimental method. Data analysis is carried out using descriptive statistics method. In this paper, a piconet pervasive system that meets Cisco standard from previous research is developed, by optimizing server-side and Bluetooth device on client-side, where the result of packet loss meets Cisco standard. All average values of throughput, delay, jitter, and packet loss parameters are eligible for Cisco standard video streaming for 5 m and 10 m measurements, where packet loss is below 5%. The results show that the greater the interference of Wi-Fi on the Bluetooth Piconet Pervasive network, the quality of video received by the client (mobile phone) decreases, marked by the increasing value of average packet loss obtained during the video streaming.

According to the latest Bluetooth specifications, the communications between slave devices within a piconet are controlled by the master node in which the master device must participate in all the information exchange activities. Consequently, how to design a polling scheme which can obviously reduce average packet delay and improve bandwidth utilization is an important issue. In this paper, we propose a traffic history based Dynamic Priority Round Robin (DPRR) polling scheme to improve the efficiency of Bluetooth piconet. As expected, the simulation results show that the proposed polling scheme can achieve a low packet delay and high bandwidth utilization.

In this paper, we have discussed the experiments performed by us on Bluetooth technology. These experiments are divided into sections that describe the extension of the limitation of Bluetooth range. Section A: Here we are showing a piconet consisting of four slaves and one master in a Bluetooth ad-hoc network ranging 200meters. Section B: Three piconets with four slaves each and slave of one piconet is the master of the other preceding piconets and the communication range is of 400 meters. Section C: Ten piconets each consisting of seven slaves and one master i.e. the maximum number of devices that can be connected within one piconet, is shown with a range of around 1000 meters and with same configuration as above. We have calculated the throughput for each section and the simulation of each configuration has been done on QualNet software of version 6.1. From the experiments we have proved that the range of Bluetooth can be extended above 100 meters. Thus by our experimentations, we have designed an announcement system using Bluetooth in which the database of the announcement system is maintained for anytime access.

This paper presents inter-piconet communications in the scenario where a shared bridge node connects two Cognitive Personal Area Networks (CPANs). The bridge carries both inter-CPAN traffic and synchronization information. The bridge exchanges synchronization information in a prioritized manner, which ensures that the two CPANs can coexist without operating on the same channel at the same time. We validate the network performance by analyzing the frequency of synchronization information exchanges. The simulation results also provide insight into the impact of various traffic. The results indicate that the proposed method is effective and efficient when the traffic load and the frequency of synchronization information exchanges are low to moderate.

We investigate the resource allocation problem, including time slot allocation, channel allocation, and power adaptation, in a millimeter Wave (mmWave) network with multiple transmission links, multiple channels, and a PicoNet Coordinator (PNC). Each link has a video session to transmit from the transmitter to the receiver. The objective is to minimize the number of time slots to finish the video sessions of all links by jointly optimizing channel allocation and time slot allocation for links, while considering the possible interference between different links on the same channel. The optimal solution for the formulated problem is computationally prohibitive to obtain due to the exponential complexity. We developed a column generation based method to reformulate the original problem into a main problem along with a series of sub-problems, with greatly reduced complexity. We prove that the optimal solution for the reformulated problem converges to the optimal solution of the original problem, and we derived a lower bound for the performance of the reformulated problem at each iteration, which will finally converge to the global optimal solution. The proposed scheme is validated with simulations with its superior performance over existing work is observed.

Rendezvous in cognitive networks refers to the ability of cognitive nodes to find each other and form a network, or to find and join an already operating cognitive network. Two main approached to rendezvous have emerged: sequence-based mechanism that guarantees maximum time-to-rendezvous and blind random hopping resilient to unpredictable primary user activity. In this paper we develop analytical models for time to rendezvous in the presence of primary user activity for the orthogonal sequence-based mechanism and a blind rendezvous mechanism integrated with a transmission tax-based MAC protocol with cooperative sensing. Our analysis shows that the blind mechanism performs better under random primary user activity, the difference being more pronounced when the number of channels is high and/or primary user activity is more intense. In addition, the probabilistic mechanism allows rendezvous with either an emergent or a fully operational CH-CPAN piconet without any interruption, unlike the sequence-based mechanism which precludes any data exchange during the rendezvous process.

IEEE 802.15.6 표준인 무선 Body Area Networks (WBAN) 은 여러 디지털 장비들을 가지고 있는 사람과 사람간의 통신규약이다. WBAN 에서는 하나의 주 디바이스와 여러 개의 부 디바이스들을 가진 한 사람 단위로 피코넷이 구성 되며, 이 피코넷은 사람의 움직임에 따라 이동하게 되며, 다른 사람과 근처에 있게 되면 피코넷간의 충돌이 일어나게 된다. 따라서 이와 같은 충돌을 감지하고 간섭을 회피하는 일이 피코넷 내부 통신을 위하여 필요하게 된다. 이 논문에서는 피코넷 충돌에 관하여 논하며, 간단하며 유용한 로컬 오프셋을 이용한 분산시간 분리 피코넷 충돌회피 방법을 제시한다. 이 제시된 방법은 여러 응용(동영상, 보안, 의료 등)을 위하여 응용마다 다른 수준의 서비스를 제공하는 하게 되는 기능을 갖게 되며, 수행된 실험 결과는 전통적인 CSMA 에 비교하여 성능이 뒤지지 않음을 보인다.

This paper presents a concurrent channel time allocation scheme used in the reservation period for concurrent transmissions in 60-GHz wireless personal area networks (WPANs). To this end, the proposed resource allocation scheme includes an efficient method for creating a concurrent transmission group by using a table that indicates whether individual streams experience interference from other streams or not. The coordinator device calculates the number of streams that can be concurrently transmitted with each stream and groups them together on the basis of the calculation result. Then, the coordinator device allocates resources to each group such that the streams belonging to the same group can transmit data concurrently. Therefore, when the piconet coordinator (PNC) allocates the channel time to the individual groups, it should allow for maximizing the overall capacity. The performance evaluation result demonstrates that the proposed scheme outperforms the random grouping scheme in terms of the overall capacity when the beamwidth is 30° and the radiation efficiency is 0.9.

Bluetooth is a wireless communication technology that is used to exchange information, at a lower cost, use low power, the ability to work or interact between applications through approved protocols is very good, and easy operation. The Bluetooth operating range works on the 2.4 GHz unlicensed ISM (Industrial, Scientific and Medical) frequency band using a frequency hopping tranceiver that is able to provide real-time data and voice communication services between Bluetooth hosts. When Bluetooth devices communicate with each other, they will form a dynamic network called piconet, a network consisting of master and slave, in one piconet of no more than 7 slaves. Bluetooth also supports connections between piconets called scattemets. The mechanism for connecting between one piconet and another is called a hop mechanism.

Purpose of this paper is to illustrate an innovative method to exploit an "RFID virtual channel" in future RFID ecosystems. Specifically, it describes a technique that allows groups of RFID readers to use the residual User Memory Bank (UM Bank) of nearby RFID tags to establish a piconet and to exchange data. The implications of such a use are extremely interesting in a perspective of future IoT applications designed for environments with a massive presence of conventional RFID tags and/or (EPCglobal compliant) sensorized RFID tags.

International audience; IEEE 802.15.3 High data rate wireless personal area networks (HDR WPANs) have been developed to communicate with devices within 10 m at high speed. A mesh network made up of a parent piconet and several child piconets can support multi-hop communications. Wireless mesh networks (WMNs) have been expected to be the ultimate solution for the next decade wireless networking, showing rapid progress and many new inspiring applications. The international standardization organizations formed working groups to address the problem of standardization for WMNs. These groups were the IEEE 802.15.5 (mesh extensions for WPANs),the IEEE 802.11s (mesh extensions for WLANs), and the IEEE 802.16a (mesh extensions for WiMAX). The IEEE 802.15.5 standard is the standard which defines specifications for including multi-hop functionality in the legacy 802.15.3 and 802.15.4 low data rate (LDR) WPAN networks. The impetus for a WPAN to operate in a mesh topology is to increase the network coverage without increasing the transmit power, to increase the route reliability via route redundancy, self-configuration, and efficient use of device battery life. In the case of meshed WPANs, multiple WPAN clusters compete for channel time in a shared superframe. Therefore, it is essential to determine the channel time requirements of each cluster with a certain number of devices and to determine how these clusters can compete to the shared channel time. In this paper, we investigate the different resource allocation mechanisms related to the meshed HDR WPANs for the 802.15.3 and the 802.15.5 standards. We introduce the single hop and the multi-hop IEEE 802.15.3 WPAN architectures. This is followed by the introduction of the IEEE 802.15.5 standard that provides the mesh capabilities for extending the coverage area of HDR WPANs. The current on-going research issues for resource allocation, including beacon interference, reservation collision etc., in both meshed 802.15.3 and 802.15.5 are alluded to.

IEEE 802.15.3 is devised for short-distance wireless connectivity within a wireless personal area network WPAN. In WPANs, a power management PM mechanism is used for power saving. The PM enables devices to sleep for one or more superframes in order to conserve power. Space division multiple access SDMA is a new technology to optimize performance of current and future mobile communication systems. In this paper, we propose an SDMA-based PM scheme, called enhanced min-degree searching EMDS for WPANs. EMDS orders the streams among multiple devices to minimize the total wake-up times. In this scheme, every device that can transmit data at the same time is checked using the SDMA. The total wake-up times will be reduced substantially if the majority of the devices can transmit data at the same time. Simulation results show that the performance of the proposed EMDS outperforms that of the existing approaches. Copyright © 2013 John Wiley & Sons, Ltd.

Purpose: There are many applications where simultaneous wireless transmission of many parameters is required to be sent to base station or to the receiver. For example, in case of mass causality events, monitoring of multiple patients by medical technicians, physicians or nurses is required where there will be more than one wireless transmitter and one wireless receiver Methods: In this paper, to demonstrate and address the issue of such applications, an adhoc network is realized by formation of a piconet in the Bluetooth environment for the real time monitoring. Each Bluetooth device captures continuous, real time simulated signals and relays the data to Bluetooth enabled laptop where received signals are further processed. Results: It is revealed that the proposed system can be used to implement Bluetooth piconet and can be an effective means for the monitoring of any parameters of multiple systems. As a proof of concept, implementation of Bluetooth piconet to capture ECG of two subjects simultaneously in real time mode is also shown. Conclusions: The data analysis suggests that an algorithm is required to address wireless transmission issues like latency along-with noise filtering. This algorithm should be easily implemented in existing Mobile/PDA/Laptop, etc. to meet the requirement of low cost and adaptability.

Bluetooth technology is particularly designed for a wireless personal area network that is low cost and less energy consuming. Efficient transmission between different Bluetooth nodes depends on network formation. An inefficient Bluetooth topology may create a bottleneck and a delay in the network when data is routed. To overcome the congestion problem of Bluetooth networks, a Cross-layer-based Adaptive Traffic Control (CATC) protocol is proposed in this paper. The proposed protocol is working on backup device utilization and network restructuring. The proposed CATC is divided into two parts; the first part is based on intra-piconet traffic control, while the second part is based on inter-piconet traffic control. The proposed CATC protocol controls the traffic load on the master node by network restructuring and the traffic load of the bridge node by activating a Fall-Back Bridge (FBB). During the piconet restructuring, the CATC performs the Piconet Formation within Piconet (PFP) and Scatternet Formation within Piconet (SFP). The PFP reconstructs a new piconet in the same piconet for the devices which are directly within the radio range of each other. The SFP reconstructs the scatternet within the same piconet if the nodes are not within the radio range. Simulation results are proof that the proposed CATC improves the overall performance and reduces control overhead in a Bluetooth network.

Bluetooth based networking is an emerging and promising technology that takes small area networking to an enhanced and better level of communication. Bluetooth specification supports piconet formation. However, scatternet formation remains open. The primary challenge faced for scatternet formation is the interconnection of piconets. This paper presents a review of the proposed approaches and the problems confronted for establishing scatternet for ad hoc networks specifically MANET. In this work, a comparison of the Blue layer algorithm with MMPI interface based algorithm on Bluetooth scatternet formation. The enhancement in the developed MMPI framework makes it a good option for scatternet applications.

The IEEE 802.15.3c wireless personal area network (WPAN) standard is designed to support highly directional wireless communications at the 60-GHz frequency band. Highly directional communications are helpful to reduce interference; hence, great potentials are provided for aggregate network throughput improvement via spatial reuse (SR). However, in 802.15.3c WPANs, the SR is limited in use since the 802.15.3c standard does not specify an explicit procedure for the SR. We design a new and simple scheme exploiting the SR, thus improving aggregate network throughput. In the proposed scheme, the 802.15.3c devices measure and report the measured channel status. Then, a controlling device, which is called the piconet coordinator (PNC) in the 802.15.3c WPAN, schedules resources available for each device. The simulation results demonstrate that the proposed scheme contributes to significant aggregate network throughput improvement. The proposed scheme is so simple that it can be easily employed for practical 802.15.3c devices. In addition, it is guaranteed to work well without conflicting with existing 802.15.3c operations.

In this paper we discuss several improvements to the security and reliability of a classic Bluetooth network (piconet) that can arise from the fact of being able to transmit the same frame with two frequencies on each slot, instead of the actual standard, that uses only one frequency. Furthermore, we build upon this possibility and we show that piconet participants can explore many strategies to increase the security of their communications by confounding eavesdroppers, such as multiple hopping sequences, random selection of a hopping sequence on each transmission slot and variable frame encryption per hopping sequence. Finally, all this can be decided independently by any piconet participant without having to agree in real time on some type of service with other participants of the same piconet.

The mmWave band of frequencies suffer from very poor diffraction capabilities which results in their high susceptibility towards beam blocking. Thus, the devices connected on a mmWave based communication network can communicate only through their line-of-sight (LoS) neighbors which makes it difficult for their deployment in indoor environments (e.g. residential households, offices etc). Additionally, the presence of non-stationery member nodes can create further difficulties in maintaining stable LoS links. In this paper, we discuss a novel approach involving dynamic control delegation (DCD) by a piconet controller to mitigate the problem of beam blocking. We propose some delegation based techniques which can be used by a piconet controller to address the problems of beam blocking and link instability to a significant extent. Finally, we validate our claim by evaluating the performance of the proposed techniques over different network scenarios.

The Bluetooth wireless communication technology which is widely used for short-range communications. It operates on 2.4GHz ISM band. In addition, Bluetooth and IEEE 802.11(Wi-Fi) devices are possible and likely to occur on the specific channel in the same location. Bluetooth devices adopt frequency hopping scheme to prevent the likelihood of mutual interferences. Although the frequency hopping can reduce some interferences, as the Wi-Fi and Bluetooth devices are coexisted in the neighborhood, the performances of both networks will be degraded likely. Because they operate on the same band and can't communicate with each other. An interference aware approach for improving the throughput of a given piconet is presented in this paper. An interference aware piconet restructuring mechanism, called IAPR, is proposed. The proposed models are based on role switch operation. The analytical results show that the proposed IAPR approach further improves the network performance between the Wi-Fi and Bluetooth devices and improves the throughput of Bluetooth radio networks.

We investigate the scheduling problem in a centralized dual-hop 60 GHz network with multiple Source-Destination (SD) pairs, relays, and a PicoNet Coordinator (PNC). The objective is to minimize the Maximum Expected Delivery Time (MEDT) among all SD pairs by jointly optimizing relay and link selection, while exploiting reflected mmWave transmissions and considering link blockage dynamics. We develop a Decomposition Principle to transform this problem into two sub-problems, one for link selection and the other for relay assignment when there is enough replays. We prove that the proposed scheme can achieve an optimality gap of just 1 time slot at greatly reduced complexity. We also develop a heuristic scheme to handle the case when there is no enough relays. The proposed schemes are validated with simulations, where their superior performance is observed.

Wireless communication is the best way to convey information from source to destination with flexibility and mobility and Bluetooth is the wireless technology suitable for short distance. On the other hand a wireless sensor network (WSN) consists of spatially distributed autonomous sensors to cooperatively monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, motion or pollutants. Using Bluetooth piconet wireless technique in sensor nodes creates limitation in network depth and placement. The introduction of Scatternet solves the network restrictions with lack of reliability in data transmission. When the depth of the network increases, it results in more difficulties in routing. No authors so far focused on the reliability factors of Scatternet sensor network’s routing. This paper illustrates the proposed system architecture and routing mechanism to increase the reliability. The another objective is to use reliable transport protocol that uses the multi-homing concept and supports multiple streams to prevent head-of-line blocking. The results show that the Scatternet sensor network has lower packet loss even in the congestive environment than the existing system suitable for all surveillance applications.

The Bluetooth technology is the convergence of Mobile Co mmun ication and Co mputing Applications. The set of Mobile Devices "Laptops, Notebook Co mputers,PDA's,Mobile Smart Phones etc" connected by Bluetooth protocol forms a Bluetooth Network or Bluetooth Piconet or WPAN.Even through the devices have numerous benefits its open nature increases the threats and risks being posed on them. The wired network faces challenging problems because of internet worms , similiarly the Bluetooth Network or WPAN faces serious problems because of Bluetooth Worms. This paper gives a comparative study of WPAN performance on impact of Bluetooth Worms in Bluetooth Piconet (symmetric) and Bluetooth Piconet(asymmetric) and derives the result how the degree of homogeneity increases the infection rate.

In this paper, we first introduce our own binary CDMA technology. Then we propose a wireless distribution automation system using the binary CDMA technology. The major research items are the binary CDMA distribution automation system, piconet configuration for remote control and monitoring, scheduling for the transmission and reception of data, and ways of applying encryption to protect wireless packet. To verify the possibility of applying wireless transmission to the distribution automation system, we experiment the implemented system in terms of the transmission rate by applying it to a real-world environment.

This study presents the enhanced Bluetree, a mesh topology scheme for Bluetooth scatternet formation. The scatternet formation algorithm includes two phases. In the first phase, a root node begins to create a conventional tree-shaped topology. To improve the network reliability of tree topology, a return connection mechanism is introduced in the second phase to generate more connection paths and to convert the tree-shape into a mesh-shaped topology. The mechanism contains two connection models including the ‘slave/slave mesh’ (SSM) and the ‘master/slave mesh’ (MSM) models. The SSM model builds a mesh-shaped topology by interconnecting more leaf nodes, whereas the MSM model connects additional intermediate nodes to establish the backbone connection in a mesh-shaped topology. Simulation results show that the enhanced Bluetree effectively improves the performance metrics, including the piconet efficiency, path length and end-to-end delay, beyond the Bluetree with more formation packets. As a result, the enhanced Bluetree not only builds a mesh-shaped topology that improves the network reliability but also generates an efficient network with less packet delay performance than a conventional Bluetree network.

Bluetooth Low Energy (BLE) is an emerging low-power wireless technology developed for short-range control and monitoring applications that is expected to be incorporated into billions of devices in the next few years. This paper describes the main features of BLE, explores its potential applications, and investigates the impact of various critical parameters on its performance. BLE represents a trade-off between energy consumption, latency, piconet size, and throughput that mainly depends on parameters such as connInterval and connSlaveLatency. According to theoretical results, the lifetime of a BLE device powered by a coin cell battery ranges between 2.0 days and 14.1 years. The number of simultaneous slaves per master ranges between 2 and 5,917. The minimum latency for a master to obtain a sensor reading is 676 µs, although simulation results show that, under high bit error rate, average latency increases by up to three orders of magnitude. The paper provides experimental results that complement the theoretical and simulation findings, and indicates implementation constraints that may reduce BLE performance.

Bluetooth is a low power, short range and inexpensive wireless technology that has limited resources. Therefore, the performance of a scatternet is highly dependent on the number of relays and their degree. The existence of unnecessary relays may increase scheduling overhead and consume system resources. In another instance, a large number of links that pass through a single relay may also decrease the system performance. Therefore, an optimum number of relays must be obtained for an efficient scatternet performance, while the system works with limited resources. The dynamic relay management (DRM) protocol is proposed to achieve the said objective and the solutions will be based on relay reduction and load balancing strategies. Through the DRM, a master reduces unnecessary relays to an optimum number and subsequently assigns them the special role as backup relays. In the event when a large number of links pass through a single relay, the master activates one of the backup relays to resolve the bottleneck, by which the load is balanced over a number of relays. Using this relay management technique, analytically the DRM protocol has reduced control overhead from O(n^2) to O(1). Empirically, through simulation of the DRM protocol, the backup relay activation has reduced delay and improved throughput (between 40% and 60%). Also, the simulation results have demonstrated an improvement on network lifetime and packet loss. All these results are evidence that the DRM has outperformed the RVM and LORP protocols for the same issue. Hence, the inefficiency of the inter-piconet scheduling in a scatternet of a Bluetooth network can be resolved by implementing the DRM protocol.

In this paper, an efficient technique for enhancing the QoS of multimedia service for an WiMedia network applying distributed cooperative medium access (D-MAC) protocol is proposed. D-MAC protocol has been proposed to support high-rate Wireless Personal Area Networks (HR-WPANs) by the WiMedia Alliance. Unlike the centralized IEEE 802.15.3 MAC, the D-MAC UWB specified by WiMedia supports all devices to be self-organized and removes the SOP (Simultaneous Operating Piconet) problem, i.e., packet collisions between overlapped piconets in the centralized IEEE 802.15.3 MAC. However the WiMedia D-MAC can`t prevent reduce the throughput degradation occurred by mobile nodes with low data rate. Therefore, a distributed cooperative MAC protocol for multi-hop UWB network is proposed in this paper. The proposed technique can intelligently select the transmission path with higher data rate to provide real-time multimedia services with minimum delay, thus enhances QoS of multimedia service.