• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.42 no.9 s.339
• /
• pp.57-64
• /
• 2005

A Piconet consists of Master device and several Slave devices. Master and Slave devices are transmitted using TDD (Time Duplex Oivision) in a Piconet. A Scattemet constructed by several Piconets communicates by a Piconet. Bluetooth Specification defines the meaning of a Scatternet. But the formation and scheduling method is not defined. For the efficient formation of a Scatternet, the preceding research proposes a tree-shape topology Scatternet. But this research passes over the characteristic of Bluetooth transmission carried out by a Piconet in the Scattemet. So this Paper proposes a efficient throughput tree formation Scatternet algorithm To improve the throughput of a Scatternet, this paper proposes a tree tolopology that guarantees the efficient throughput of a Piconet

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.8A
• /
• pp.613-619
• /
• 2003

Bluetooth is a communication technology enabling short-range devices to be wirelessly connected. A master and one or more slave devices are connected to form a piconet, and piconets are joined to form a scatternet. The units participating in two or more piconets in a scatternet, is called bridge or gateway nodes. In order to operate the scatternet efficiently, both piconet scheduling for the master and slaves of a piconet, and scatternet scheduling for the bridge nodes are playing important roles. In this paper, we propose a traffic-adaptive dynamic scatternet scheduling algorithm based on rendezvous points and rendezvous windows. The performance of the proposed algorithm is compared and analyzed with that of a static scheduling algorithm via simulations. Simulation results show that our algorithm can distribute wireless resources efficiently to bridge nodes depending on the traffic characteristics.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.15 no.5
• /
• pp.13-24
• /
• 2005

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 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 wars 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, we applied a security service and resolved the vulnerabilities of the current piconet by configuring an expanded form of the current tree-shaped structure.

• Journal of Advanced Navigation Technology
• /
• v.6 no.2
• /
• pp.151-157
• /
• 2002

This paper has investigated the PER performance and the packet throughput of Bluetooth multi-piconet in the presence of impulsive noise, Rician fading, and co-channel interference. Specially, it is simulated the effect of co-channel interference in Bluetooth multi-piconet. From the simulation results, it is obtained that the co-channel interference due to multi-piconet and impulsive noise affects performance of Bluetooth multi-piconet. And, we have known that the SAW-ARQ method is very efficient to improve the performance of Bluetooth packet transmission.

• Proceedings of the Korean Information Science Society Conference
• /
• 2004.04a
• /
• pp.601-603
• /
• 2004

본 논문은 블루투스 피코넷을 이용하여 임베디드 시스템을 원격으로 제어하는 것을 목적으로 한다. 이를 위하여 범용 임베디드 시스템에 리눅스 커널을 포팅하고 근거리 무선 통신 규격인 블루투스 기술을 이용하여 산업장비 원격으로 제어하는 블루투스 피코넷 시스템을 설계한다. 각 임베디드 장비는 블루투스 피코넷을 이용하여 개별 제어분만 아니라 동시제어가 가능하도록 하였다. 이것은 임베디드 웹 서버를 통해 현장분만 아니라 어디에서든지 원격 제어가 가능하다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.7B
• /
• pp.469-476
• /
• 2008

In this paper we analyze the packet interference probability and the aggregated throughput of a WPAN in which a number of Bluetooth piconets share the ISM band with WLANS. Using an Adaptive Frequency Hopping algorithm, when the AFH is employed, the number of hops available to the Bluetooth piconets varies depending on the number of independent WLANs within the piconet's radio range. Using a packet collision model in a piconet cluster, we give an analysis of the packet interference probability and the aggregated throughput as a function of the available hops for the AFH algorithm. We also present an analytical model of packet interference with multi-path fading channel in a cluster of piconets. Through analysis, we obtain the packet collision probability and aggregated throughput assuming capture effect. Numerical examples are given to demonstrate the effect of various Parameters such as capture ratio, Rice factor and cluster size on the system performance.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.3B
• /
• pp.112-122
• /
• 2008

Basing on Piconet, The Bluetooth System forms network and transmits data. There is one Master and maximum 7 Slave bluetooth devices in one piconet. A job scheduler performed by Master bluetooth device, gives the chance of data transmission to Slave bluetooth devices, which connected to Master, using polling method in piconet. The maximum data rate is 723.2 kb/s when it uses ACL link with DH5 packet type in a piconet which is constructed by two bluetooth devices. However, if there are one master and two slave devices in a piconet, then the maximum data rate is reduced to a half(361.6kb/s), because a master device has to support same data rate for all connected devices. And, there is the defect in scatternet when data transmission rate becomes low(Maximum rate: 302.2kb/s). This paper proposals the new ad-hoc network topology called "DoublePico"for overcome the low data transmission in scatternet which is constructed by piconets. The method of doublepico that represented in this paper makes high data transfer rate(Maximum rate: 457.57kb/s) in bluetooth ad-hoc networks.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.9B
• /
• pp.604-611
• /
• 2007

In this paper, we present an analysis of the throughput when there are multiple piconets and WLAN sharing the ISM bands. The analysis takes channel propagation characteristics and the capture effect. We also propose an algorithm which can be used to reduce the amount of channel scanning. By using traffic prediction of the interfering WLAN, we are able to maintain a reasonable performance in terms of fraction of time channel is wasted due to collisions or unused channel. Through computer simulation, we demonstrate that the proposed algorithm achieves reduced scanning frequency.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2006.11a
• /
• pp.207-211
• /
• 2006

IEEE 802.15.4a에서는 첩(Chirp)신호을 이용한 UWB(Ultra Wide Band) 시스템으로서 DBO(Differential Bi-Orthogonal)-CSS(Chirp Spread Spectrum) 기술을 선택적 표준안으로 정하였다. 기존 DBO-CSS에서는 다중 피코넷 간섭(MPI; Multiple Piconets Interference)을 피하기 위하여 각 피코넷 별로 Different Time-Gap을 할당하고 있다 하지만 완벽한 직교성이 존재하지 않는다는 특성을 가지고 있어서 간섭의 영향에 민감할 수 밖에 없고, 무선통신시스템의 성능 저하를 야기시킨다. 본 논문에서는 각 피코넷 별로 보다 완전한 직교성을 확보하기 위하여, 확산코드기법을 적용한 CSS 변복조 알고리즘을 제안하고, 또한 일정한 시간 구간동안 연속적인 직교특성을 가지는 이진 ZCD(Zero Correlation Duration) 코드를 사용하여 BER(Bit Error Rate) 성능 분석을 통해 SOP(Simultaneously Operating Piconets) 환경에서 다중 피코넷 간섭 등의 영향을 효과적으로 제거함을 확인하였다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.6B
• /
• pp.350-357
• /
• 2007

The IEEE 802.15.3 high-rate WPAN has been developed to communicate with devices within l0m. A piconet consists of one Piconet Coordinator (PNC) and several devices. The devices associated with a parent piconet can become child PNCs in order to form child piconets. A mesh network made up of a parent piconet and several child piconets can support multi-hop communications. In this paper, we analyze the maximum level and the avaliable superframe size to make the best use of bandwidth for multi-hop communications, and compare the analysis with the simulation results in terms of time to discover devices for multi-hop communications. The average number of levels in mesh networks is shown to be about 1.9 when the number of devices increases within a fixed area. We have also shown that the maximum available superframe size is 52ms and the discovery time is approximately 155ms.