• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.299-299
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• 2004

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.310-310
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• 2004

• The KIPS Transactions:PartC
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• v.11C no.6 s.95
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• pp.829-834
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• 2004

Nodes communicate through wireless channels under peer-to-peer level in ad-hoc mobile networks. The nodes are free to move around in a geographical area and are loose]y bounded by the transmission range of the wireless channels. Also, a node is completely free to move around, there is no fixed final topology. Hence, to manage the inter-node communication and data exchange among them a leader node is required. In this paper we introduce an efficient leader election algorithm for mobile ad hoc networks where inter-node communication is allowed only among the neighboring nodes. Furthermore we present the result of performance evaluation through simulation. The algorithm is efficient and practical since it uses least amount of wireless resources and does not affect the movement of the nodes.

• The KIPS Transactions:PartC
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• v.11C no.7 s.96
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• pp.917-922
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• 2004

Mobile ad hoc networks (MANETs) are networks of mobile nodes that have no fixed network infrastructure. Since the mobile node's location changes frequently, it is an attractive area to maintain the node's location efficiently. In this paper, we present an adaptive randomized database group (ARDG) scheme to manage the mobile nodes mobility in MHANETs. The proposed scheme stores the network nodes' location in location databases to manage the nodes' mobility. When a mobile node changes its location or needs a node's location, the node randomly select some databases to update or que교 the location information. The number of the selected databases is fixed in the case of querying while the number of the databases is determined according to the node's popularity in the case of updating. We evaluated the performance of the proposed scheme using an analytical model, and compared the performance with that of the conventional randomized database group (RDG) scheme.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.7
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• pp.1471-1478
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• 2011

A typical standard of vehicular ad hoc networks, WAVE which consists of IEEE 1609.x Family standards and IEEE 802.11p standard, includes the multi-channel coordination and channel synchronization function to provide safety services or public services during a car is driven. Generally, the performance of data communication and networking technologies is evaluated by using simulation tools, such as ns-2, OPNET, OPNET++, etc. However, these tools doesn't provide the operations of WAVE protocol. Therefore, in this paper, we implement and verify WAVE simulation program based on ns-2.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.7B
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• pp.642-651
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• 2006

In ad-hoc network, the most of existing packet scheduling schemes provides throughput-based fairness. To provide throughput-based fairness, it basically supposes that the channel capacity is fixed. But, the supposing that the channel capacity is fixed is not appropriate because IEEE 802.11b and 802.11g which are normally used for organizing ad-hoc network can provide various data rate according to channel conditions. So, we define time-based fairness for each flow to consider multi-rate and suggest the MRADPS reaching the defined time-based fairness. Simulation result shows that MRADPS improves the total network throughput in ad-hoc network with providing time-based fairness to each flow.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.848-850
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• 2014

Mobile Ad hoc Networks(MANET) is consist of node that has mobility, MANET build cluster formation for using energy efficient. In existing LEACH algorithm elect cluster head node in coverage area by distribution function. However, when the cluster head node, that elected by distribution function, is divided coverage area unevenly, the network can't consumption energy efficiency. To solve this problem, we proposed CSWC(Coverage Scheduling Weight-value Control) algorithm. When the coverage area is divided nonchalance, proposed algorithm increased number of hops, that determines coverage area, for balance coverage area. As the result proposed algorithm is set balance coverage area, the network consumption energy efficiency.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.60 no.4
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• pp.257-261
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• 2011

In this paper, we research the OLSR(Optimized Link State Routing Protocol) of the mobile ad-hoc network protocols, and design the system implementation based on the Embedded Linux for the Ubiquitous Space construction. We prove the performance of proposed system in the various experiment environments through several scenarios which is about transmitting the image data on the mobile ad-hoc network environment.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06d
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• pp.163-166
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• 2007

통신모듈이 포함된 많은 컴퓨팅 장치들이 다가오는 미래에는 유비쿼터스 네트워크 디바이스가 될 것이다. 센서 네트워크도 그런 유비쿼터스 네트워크의 어플리케이션이다. 대부분의 경우 센서 네트워크는 플러딩기반의 on-demand 에드혹 라우팅 프로토콜을 사용하나, 플러딩에 따른 중복된 패킷 전송을 최소화 하기 위해, 위치 정보를 사용하고 장애물까지 고려한다. 본 논문은 건물 내 유비쿼터스 센서 네트워크에서 위치 기반과 장애물을 고려한 플러딩을 제안한다.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.220-222
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• 2004

이동 애드 혹 망을 구성하는 노드들은 일반적으로 배터리 전력을 사용하기 때문에 이들의 에너지 소모량을 줄이는 연구들이 각 계층에 대해 이루어져 왔다. 몇몇 연구들은 매체 접근 제어 프로토콜로 많이 이용되는 IEEE 802.11 DCF의 전력 소비량을 줄이기 위한 전력 제어 기법을 제시하였다. 기본 전력 제어기법(BASIC Power Control Protocol)은 RTS-CTS와 DATA-ACK 에 대해서 각각 다른 전력을 적용하는 것이다. RTS-CTS는 최대 전력으로 전송되고, DATA-ACK는 불필요한 에너지 낭비를 줄이기 위해 최소한 의 필요한 전력으로 전송하였다. 그러므로 DATA-ACK의 전송범위(transmission range)와 전송파 감지영역(carrier sensing range)은 RTS-CTS의 영역보다 작아진다. 전송파 감지영역에서 RTS-CTS를 감지한 노드들은 신호를 올바로 해석할 수 없으므로 NAV 값을 EIFS로 설정한다. 이 EIFS 구간은 충돌을 막기에는 너무나 짧기 때문에. EIFS 구간이 지난 후에 채널이 비어있는 상태로 간주하고 전송을 시도하게 된다. 이에 따라 DATA-ACK 수신에 있어서 충돌율이 증가하게 되고 네트웍 전체 처리량이 감소하게 된다. 본 논문에서는 기본 전력제어 기법이 가지는 문제점을 해결하고 전체 네트웍 처리량을 향상 시킬수 있는 새로운 전력제어(Power Control) MAC 프로토콜을 제안하였다.