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IEEE 802.15.3 is designed for high data rates multimedia applications in Wireless Personal Area Network (WPAN). The piconet is the basic topology of IEEE 802.15.3, which consists of a number of independent devices and a Piconet Coordinator (PNC). Medium Access Control (MAC) protocol plays a vital role in determining the energy consumption of all devices within a piconet. IEEE 802.15.3 MAC adapts a hybrid approach, i.e., a combination of CSMA/CA and TDMA, in order to support real-time communication while maintaining the desired Quality of Service (QoS). The channel is bounded by superframe structures where each superframe consists of a beacon, a Contention Access Period (CAP), and a Channel Time Allocation Period (CTAP). In this paper, we focus on the CAP part of the superframe. Numerical approximations are derived to analyze the performance of CSMA/CA used in CAP in terms of probability of successful transmission, average number of collisions, and normalized throughput. Numerical results are validated by extensive simulations using NS-2 simulator.

Bluetooth is a low cost wireless technology for short range device. The Bluetooth system can be used for different kinds of data exchange; it carries both synchronous and asynchronous data traffic. Bluetooth basic network is called piconet; multiple connected piconets are called scatternet. The scatternet structure has a great impact on the network performance. Without considering the traffic flow, a scatternet may suffer from serious congestion problem. The objective of this research work is to propose a new Bluetooth Inter-piconet Congestion Avoidance (ICA) protocol by network restructuring. The main objectives of proposed protocol are to share the traffic load and find the shortest routing path for pairs of Bluetooth sources and destinations. Simulation results show that proposed protocol reduces control overhead, decreases delay and improves network throughput.

Bluetooth is an established standard for low cost, low power, wireless personal area network. Currently, Bluetooth does not support any roaming protocol in which handoff occurs dynamically when a Bluetooth device is moving out of the piconet. If a device is losing its connection to the master device, no provision is made to transfer it to another master. Handoff is not possible in a piconet, as in order to stay within the network, a slave would have to keep the same master. So, by definition intra-handoff is not possible within a piconet. This research mainly focuses on Bluetooth technology and designing a roaming protocol for Bluetooth equipped multi agent systems. A mathematical model is derived for an agent. The idea behind the mathematical model is to know when to initiate the roaming process for an agent. A desired trajectory for the agent is calculated using its x and y coordinates system, and is simulated in SIMULINK. Various roaming techniques are also studied and discussed. The advantage of designing a roaming protocol is to ensure the Bluetooth enabled roaming devices can freely move inside the network coverage without losing its connection or break of service in case of changing the base stations.

IEEE 802.15.3 High-rate Wireless Personal Area Networks (WPANs) have been developed to communicate with devices within 10m at high speed. A mesh network made up of a parent piconet and several child piconets can support multi-hop communications. In this paper, we propose an efficient Channel Time Allocation (CTA) method and routing algorithm for multi-hop communications in IEEE 802.15.3 high-rate WPAN mesh networks. The proposed CTA allocation method allows sufficient CTA allocation for the relay PNCs. The proposed routing algorithm is tree-based, and the routing tables of parent PNCs and child PNCs are created by efficient device discovery process to find the shortest paths via parent PNCs or subordinate child PNCs. We evaluate the performance of the proposed algorithms via simulations. The proposed algorithms are shown to extend the communication range by multi-hop exchange of packets and to provide sufficient Channel Time Allocations (CTAs) for parent and child PNCs.

Ultra-wideband (UWB) technique has been considered as a possible candidate for high rate Wireless Sensor Network (WSN) because of its higher capacity with low power operation. The IEEE 802.15.3 Medium Access Control (MAC) protocol works on a Time Division Multiple Access (TDMA) basis within a piconet. With multiple overlapped piconets, the current protocol uses Parent/ Child (P/C) or Parent /Neighbor (P/N) configuration to avoid interpiconet interference, but the throughput of P/N or P/C cannot exceed that of single piconet. In this paper we propose an intelligent MAC protocol to cooperate with the UWB system based on Multi-Carrier Code Division Multiple Access (MC-CDMA). The proposed protocol uses Intermediate Sensor Device (ISDEV) to connect Piconet Coordinators and adaptively arrange 2 simultaneous data transmission links during each Channel Time Allocation (CTA). Our simulation results demonstrate the proposed scheme can achieve a higher throughput with an acceptable compromise at link success probability in multiple overlapped sensor networks.

The IEEE 802.15.3 Medium Access Control (MAC) protocol is designed to support low power and high rate Wireless Personal Area Networks (WPANs). It works on a Time Division Multiple Access (TDMA) basis within a piconet, which guarantees interference-free connections. However, the current protocol is not efficient for Simultaneously Operating Piconets (SOPs), which are linked by the parent/child (P/C) and parent/neighbor (P/N) relationships. It provides interference mitigation but the throughput is limited since the channel time is exclusively allocated. In this paper we propose Intelligent Channel Time Allocation (Intelligent CTA), which includes Public CTA and Normal CTA, to intelligently manage the inter-piconet interference (IPI). The proposed scheme is able to greatly reduce the IPI. Based on the DS-UWB system, the simulation results show that the proposed scheme can effectively support the coexistence of SOPs and it can achieve higher throughput without significant loss of link success probability (LSP) in the SOPs.

IEEE 802.15.3 high-rate Wireless Personal Area Networks (WPANs) is a short range communication technology, in which devices (DEVs) of a piconet communicate with a Piconet Coordinator (PNC). An extension of the communication area in WPAN via formation of a multi-piconet is one of the most challenging issues. Although a concept of multi-piconet has been defined in the IEEE 802.15.3 WPAN standard, a detailed formation mechanism of multi-piconet is not presented. In this paper, we propose efficient multi-piconet formation algorithms, Piconet Coordinator To Device (PCTD) and Device To Piconet Coordinator (DTPC). We evaluate the performance of the algorithms via simulations. The proposed algorithms are shown to extend the communication area with one to three levels and to provide sufficient Channel Time Allocations (CTAs) for subsidiary piconets in IEEE 802.15.3 WPAN.

In this paper, we propose the UWB system as a wireless HD multimedia transmission technology in a home network. We examine the piconet of UWB system and analyze the performance by using the development kit in a real office and empty space environments.

The IEEE 802.15.3 medium access control (MAC) protocol is standard for high bit rate wireless personal area network (WPAN) The open or association management channel time allocations (MCTAs) are used by devices(DEVs) for sending command messages or association request command to piconet coordinator (PNC) by means of slotted aloha random access manner Based on slotted aloha scheme the binary back-off algorithm has been considered as a primary contention resolution candidate due to its simple operation However it is not appropriate for the future wireless networks because of low throughput and high delay and delay variance Without loss of generality the goals of the random multiple access algorithm are to maximize the throughput and to minimize the average packet delay In this paper, we propose a new multiple access protocol named staggering algorithm working on top of slotted aloha scheme The performance results by NS-2 simulation show that the proposed algorithm achieves the maximum throughput up to 0.54 and guarantees the QoS in terms of delay and delay variance of realtime multimedia traffic.

In this paper we view the scheduling problem in Bluetooth as a bin packing problem (BPP) with k-preview items. We analytically demonstrate that even though the First Fit Decreasing with k-preview Items (FFD-kI) algorithm has the same asymptotic worst case performance ratio as the Look Ahead Round Robin (LARR) algorithm, it achieves a competitive asymptotic average case performance ratio which is superior to LARR and Round Robin (RR). We present both worst case and average case results. Extensive simulation results show that in a Bluetooth piconet, the FFD-kI algorithm achieves significantly better throughput and channel utilization performances over LARR and RR.

In this paper, we propose an overlapping communication protocol using improved time-slot leasing in the Bluetooth WPANS. One or many slave-master-slave communications usually exist in a piconet of the Bluetooth network. A fatal communication bottleneck is incurred in the master node if many slave-master-slave communications are required at the same time. To alleviate the problem, an overlapping communication scheme is presented to allow slave node directly and simultaneously communicates with another slave node to replace with the original slave-master-slave communication works in a piconet. This overlapping communication scheme is based on the improved time-slot leasing scheme. The key contribution of our improved time-slot leasing scheme additionally offers the overlapping communication capability and we developed an overlapping communication protocol in a Bluetooth WPANs. Finally, simulation results demonstrate that our developed communication protocol achieves the performance improvements on bandwidth utilization, transmission delay time, network congestion, and energy consumption.

Due to the changes in the wireless information environment, there has been an increased demand for various types of information. Accordingly, many wireless communication technologies have been studied and developed. In particular, studies on ubiquitous close distance communications are well underway. Lately, the focus has been on the Bluetooth technology due to its applicability in various environments. Applying Bluetooth connectivity to new environments such as ubiquitous or sensor networks requires finding new ways of using it. Thus, this research analyzed the vulnerability on the limited number of slaves in a piconet configuration through the current Bluetooth communication and proposed an expanded Bluetooth piconet formation method, regardless of the number of slaves inside the piconet even if it is not configured in a scatternet. In the proposed method, a security service was applied and the vulnerabilities of the current piconet configured as an expanded form of the current tree-shaped structure.

IEEE 802.15.3(a) is working to design a higher speed PHY enhancement amendment to 802.15.3 such as ultra-wideband which can provide precise timing and location information. This paper proposes an effective resource allocation mechanism which can guarantee the QoS properties of multimedia traffics and provide higher channel utilization by the aid of location information. The proposed mechanism, which is executed by the piconet coordinator, consists of three components: grouping, call admission control, and best effort traffic maximization.

In this paper, we focus on the Bluetooth wireless network, analyzing its ability to support Quality of Service (QoS) requirements defined by the application. We focus on two QoS parameters : (i) an application constraint denoting the importance degree of a message, and (ii) an end-to-end delivery deadline. In a first step, we introduce a local scheduling accounting for the two QoS parameters in One-Round Robin (1-RR). We evaluate the performances of this enhanced version. In a second step, we define a new Bluetooth global scheduling, called Class-Based Earliest Deadline First (CB-EDF). It takes into account the two QoS parameters at the global level. Simulation results show that CB-EDF achieves a better service differentiation than enhanced 1-RR and allows the coexistence of messages with different application constraints.

The emerging radio technology Bluetooth offers configuration- and administration-free ad hoc networking between mobile terminals. A simple so-called Bluetooth piconet consisting of up to eight active devices can easily be formed with products available today. The Bluetooth specification, however, goes a step further and indicates the combination of several piconets into a larger network, a so-called scatternet. But any details of this self organization are far beyond the scope of the specification – scatternet formation is an active research area.

Several Bluetooth piconets can be interconnected using an inter-piconet unit called a bridge node to form a Bluetooth scatternet. The bridge node can make its presence in each piconet on a time division basis by switching its frequency hopping sequence. Without a careful coordination among nodes, piconet switching can result in conflicts and idle time in communication, which impact the throughput of the entire scatternet. In this paper we present an efficient inter-piconet scheduling scheme called LSRR (Limited Sniff Round Robin). LSRR is a locally coordinated scheduling scheme that assigns presence points in round robin fashion among different piconets. LSRR uses the sniff mode as the inter-piconet switching mechanism and dynamically adjusts the duration of communication events based on the past history of transmissions. Simulation results show LSRR outperforms the pure round robin scheme in terms of throughput and delay.

Efficient communication in Bluetooth scatternets requires design of intra and inter-piconet scheduling algorithms, and therefore numerous algorithms have been proposed. However, due to inherent complexities of the Bluetooth Medium Access Control (MAC), the performance of such algorithms has been analyzed mostly via simulation. We show that a piconet operated according to the limited (pure round robin) scheduling algorithm is equivalent to a 1-limited polling system and utilize methods developed for the analysis of such systems to analyze this algorithm. We present exact analytic results regarding symmetrical piconets with bi-directional traffic. Our results differ from the corresponding analytical results presented as exact in [12],[13],[14],[16],[19], and [21]. We show that [14] actually presents approximate results, as it ignores important dependencies incorporated in the piconet operation model. Consequently, [14] underestimates the intra-piconet delay, in some cases by more than 50%. We also indicate that for similar reasons the analyses presented in [12],[13],[15],[16],[17],[18],[19],[20], and [21] seem to provide only approximate results.

Radio resource (bandwidth) and power are limited in wireless personal networks. So these scarce resources are to be used efficiently from the system's perspective while they should be allocated fairly or differently depending or users' requirements or traffic characteristics from individual user's perspective. We propose an integrated and efficient piconet and scatternet scheduling mechanism. In our mechanism, the scheduling of scatternet and piconet is performed by appropriately selecting rendezvous window or sniff parameters according to either QoS requirements or dynamic traffic characteristics. We have shown via analysis and simulations that ours can achieve differentiated and efficient bandwidth allocation both in a scatternet level and in a piconet level as well as power saving, which is desired for wireless personal area network systems.

During recent years, there has been an increasing interest in the research and development of Wireless Personal Area Networks (WPANs). In particular, Bluetooth has been widely acknowledged as a suitable solution to enable small electronic devices with wireless connectivity. However, a number of issues remain to be solved before Bluetooth-equipped devices can provide users with full ad-hoc networking capabilities. This paper explores and discusses the applicability of mobile agent technology to address a specific issue in Bluetooth networks: the scatternet formation problem. It is argued that mobile agent technology can be efficiently employed to solve this particular problem in Bluetooth WPANs, overcoming restrictions seen in existing schemes. Simulations results demonstrate the effectiveness of using mobile processing to solve the scatternet formation problem.

Bluetooth is a promising wireless technology aiming at supporting electronic devices to be instantly interconnected into short-range ad hoc networks. The Bluetooth medium access control protocol is based on the Master/Slave concept wherein any communication between slave devices has to go through the Master. While this model provides for simplicity, it incurs a longer delay between any two slave devices due to far from optimal packet forwarding, the use of double the bandwidth, and also additional energy wastage at the Master. Moreover, if more than two devices want to communicate as a group, this can only be achieved by either multiple unicast transmissions or a piconet-wide broadcast, clearly resulting in inefficiency. In this paper, we propose a novel Dynamic Slot Assignment (DSA) scheme whereby the Master device dynamically assigns slots to Slaves so as to allow them to communicate directly with each other without any Master intervention. This proposed communication architecture also provides for Quality of Service (QoS) requests, admission control, and multi-device conversation by which a multicast-like communication is implemented within a piconet. Through extensive simulation, we observe that DSA drastically enhances Bluetooth performance in terms of delay and throughput, while significantly reducing power consumption at the master and also of the overall piconet.

This paper addresses issues for the establishment of multihop ad-hoc networks based on Scatternet formation using bluetooth. We describe a new approach of inter-piconet communication. Differing from existing protocols, the design allows the slave to establish contact with other slaves present in the piconet without passing through the master. All new piconet clock synchronization will depend on only one master leader. This will increase the capacity of slave to switch from one piconet to another every slot, increasing consequently the traffic data transfer. We perform a simulation that provides evidence of improving average throughput.

In accordance with the changes in the wireless communication environment, there has been a great need to satisfy the demand for diverse modes of information exchange. However, Bluetooth has weaknesses in its security features when its in -house security services are applied to networks. The purpose of this study is to propose a secure Bluetooth scenario with an upgraded security feature. This paper first reviews the general characteristics and security features of Bluetooth together with an analysis of its weaknesses, and presents the formation and maintenance process of Bluetooth piconet with is created by using ECDSA and group key in the ACL (Asynchronous Connection-less Link) connection through a secure Bluetooth inquiry process.

The performance of a single Bluetooth piconet is analyzed using the theory of M/G/1 queues with vacations. Analytical results for probability distributions of packet access time and service cycle time are derived. Two scheduling policies, limited and exhaustive service, are considered. In general, exhaustive scheduling was found to perform better than limited service. Results were confirmed through simulations.