• Proceedings of the Korea Society of Information Technology Applications Conference
• /
• 2005.11a
• /
• pp.177-178
• /
• 2005

Wireless 1394 over IEEE802.15.3 must allow a data reserved for delivery over a wired 1394 network to be delivered over an IEEE802.15.3 wireless network through bridging IEEE 1394 to IEEE802.15.3. Isochronous transfers on the 1394 bus guarantee timely delivery of data. Specifically, isochronous transfers are scheduled by the bus so that they occur once every $125\;{\mu}s$ and require clock time synchronization to complete the real-time data transfer. IEEE1394.1 and Protocol Adaptation Layer for IEEE1394 over IEEE802.15.3 specify clock time synchronization for a wired 1394 bus network to a wired 1394 bus network and wireless 1394 nodes, which are IEEE802.15.3 nodes handling 1394 applications, over IEEE802.15.3. Thus, the clock time synchronizations are just defined within a homogeneous network environment like IEEE1394 or IEEE802.15.3 until now. This paper proposes new clock time synchronization method for wireless 1394 heterogeneous networks between 1394 and 802.15.3. If new method is adopted for various wireless 1394 products, consumer electronics devices such as DTV and Set-top Box or PC devices on a 1394 bus network can transmit real time data to the AV devices on the other 1394 bus in a different place via IEEE 802.15.3.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.5C
• /
• pp.472-478
• /
• 2010

In the environment of wireless communication system of IEEE 802.15.3a UWB standard, the angle of arrival(AOA) estimation technique for the indoor wireless positioning algorithms, based on the AOA parameter estimation which fits well for the wireless communication channel and shows high estimation accuracy, is proposed. After the UWB signal model, based on the IEEE 802.1.3a standard, is constructed, the average weighted MUSIC technique is proposed, which shows better estimation accuracy than those of conventional estimation technique. Through the simulation studies, the environment of the indoor wireless positioning system including the IEEE 802.15.3a channel is configured and we demonstrate better estimation results by the proposed AOA estimation technique than those from the conventional method.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2012.11a
• /
• pp.848-849
• /
• 2012

IEEE 802.15.3c 는 IEEE 802.15.3 WPAN 에 mmWave(millimeter wave) 기반 물리 계층의 표준화를 하는 것을 목적으로 하며, 사용 대역의 특성상 지향성(directional) 안테나를 이용해서 통신을 한다. 또한 하나의 노드를 중심으로 피코넷을 형성하고 그 피코넷 내에서 peer 노드들 간 직접 통신을 위해서 peer 노드를 발견하는 효율적인 기법이 요구된다. 본 논문에서는 지향성 안테나를 사용하는 IEEE 802.15.3c 의 특성을 고려한 효율적인 이웃 발견 기법을 제안한다.

• Journal of Digital Contents Society
• /
• v.13 no.3
• /
• pp.353-358
• /
• 2012

Wireless sensor networks consist of resource constraint devices which typically send data measured by sensors attached to the end devices towards a coordinator. The most often used medium access control protocol used in wireless sensor networks is the standard IEEE 802.15.4, where it is wireless standard introduced for low power, low cost wireless communication with moderate data rates. In this paper, we present implementation of both the IEEE 802.15.4 protocol stack and UART interface on the TI CC2530. We show that data via UART of our implemented IEEE 802.15.4 board are transmitted correctly in terms of captured frames.

• TTA Journal
• /
• s.100
• /
• pp.161-169
• /
• 2005

IEEE802.15에서 표준화가 진행중인 WPAN(wireless personal network)은 개인영역 네트워크 혹은 근거리 무선 네트워크를 구축하기 위한 기술로, 개인용 컴퓨터, PDA, 주변기기, 휴대전화, 가전 등의 휴대나 이동 컴퓨팅을 위한 기술이다. IEEE802.15.1에서는 블루투스, IEEE802.15.4에서는 ZigBee를 위한 저속 WPAN(low rate WPAN) 그리고 IEEE802.15.3에서는 고속 WPAN(high rate WPAN)에 대한 표준화를 담당하고 있다. 본 고에서는 IEEE802.15 산하 TG3a에서 표준화 중인 Alt-PHY 기술로 경합을 벌이고 있는 MBOA(Multi-Band Orthogonal frequency division multiplexing Alliance) UWB(ultrawideband)에 대한 활성화를 꾀하고 있는 WiMedia Alliance의 시험인증 동향을 고찰하고자 한다.

• Journal of the Korean Society of Industry Convergence
• /
• v.20 no.3
• /
• pp.205-212
• /
• 2017

This paper focuses on worst-case delay analysis of the time-triggered IEEE 802.15.4 protocol to satisfy the industrial quality-of-service (QoS) performance. The IEEE 802.15.4 protocol is considered to be unsuitable for industrial networks because its medium access control method is contention-based CSMA/CA, which exhibits unstable performance with an unbounded delay distribution under heavy traffic. To avoid these limitations, this paper presents a time-triggered version of the nonbeacon-enabled network of IEEE 802.15.4 that relies on a time division multiplexing access (TDMA) method implemented in the application layer without any modification of specification. The timing analysis of this time-triggered IEEE 802.15.4 was executed, and the worst-case transmission delay was calculated. Based on this analysis, the time-triggered IEEE 802.15.4 is a promising alternative for wireless industrial networking.

• Journal of KIISE:Information Networking
• /
• v.34 no.3
• /
• pp.175-185
• /
• 2007

In IEEE 802.15.4 (Low-Rate Wireless Personal Area Network) specification, a successful reception and validation of a data or MAC command frame can be confirmed with an acknowledgment. However, the specification does not support security for acknowledgment frame; the lack of a MAC covering acknowledgments allows an adversary to forge an acknowledgment for any frame. This paper proposes an identity authentication mechanism at the link layer for acknowledgment frame in IEEE 802.15.4 network. With the proposed mechanism there is only three bits for authentication, which can greatly reduce overhead of device. The encrypted bit stream for identity authentication will be transmitted to device by coordinator within association process. Statistical method and simulation results prove that our mechanism is successful in handling MAC layer attack.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2014.04a
• /
• pp.215-217
• /
• 2014

본 논문에서는 ns-3 기반의 IEEE 802.15.4 모의 성능 평가에 대해 기술한다. IT 기술의 발달과 함께 차세대 전력망인 '스마트 그리드'가 대두되고 있다. 이에 따라 무선 센서들 간의 통신을 위해 IEEE 802.15.4 표준 기술이 채택되고 있다. IEEE 802.15.4 표준에는 beacon-enabled mode 와 non beacon-enabled mode 두 가지 채널 접근 기법이 존재하지만 특정 기법의 용도와 목적에 대해서는 구체적으로 명시되지 않는다. 따라서 본 논문에서는 스마트 그리드 환경에서 IEEE 802.15.4 의 두 채널 접근 기법의 성능을 시험하고 beacon-enabled mode 와 non beacon-enabled mode 간의 성능 분석을 통해 beacon-enabled mode 의 효용성에 대하여 연구한다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.11 no.1
• /
• pp.28-33
• /
• 2007

In spite of the large interest in the 802.15.4 standard, no realistic experimental research of its behaviour exists to date except a few works by simulations and analytical modeling. In this paper, we have established realistic environment of IEEE 802.15.4 network and analyze its behaviour under various conditions as like 1) maximum throughput of 802.15.4 MAC, 2) MAC fairness. and 3) throughput and m rate under co-existence of 802.11 Wi-Fi wireless networks.

• Journal of Communications and Networks
• /
• v.10 no.3
• /
• pp.301-307
• /
• 2008

In this paper, the impact of channel sensing methods to IEEE 802.15.4 under the interference of IEEE 802.11b are analyzed. Two different channel sensing methods, energy detection and carrier sense, are considered. An average transmission delay, a throughput, and a power drain rate are used as performance measures. Those performance measures of IEEE 802.15.4 under the interference of IEEE 802.11b are analyzed mathematically. The simulation results are shown to validate the analytic results.