• Proceedings of the Korea Information Processing Society Conference
• /
• 2009.11a
• /
• pp.917-918
• /
• 2009

This study evaluated the level of performance improvement in the form of a simulated experiment by adding fixed node in the middle of the network as a way to improve mobile ad.hoc network performance. The result showed that the performance level was much higher when fixed node was used together than when mobile node was used only, and the comparison of the mobile speed of mobile node also showed that use of fixed node together had higher performance. Moreover, the evaluation in accordance with the number of fixed node showed that more number of fixed node had shorter time delay. Further study following this on how many fixed node should be added on the ad.hoc network will ensure establishment of more reliable ad.hoc network.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.9
• /
• pp.29-35
• /
• 2009

In this paper we propose a mobile ad-hoc routing protocal based on AODV(Ad hoc On demand Distance Vector) with traffic management support and evaluate the performance through simulation. The average reception rate is increased by establishing the shortest route, considering in advance the usable communication resources at each node. For performance evaluation, we analyze the average data reception rate, considering the node mobility.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.9
• /
• pp.1819-1828
• /
• 2009

Until now, much research on cooperative communications to increase system throughput at Ad Hoc networks has been provided. In this paper, in order to enhance system throughput much more at Ad Hoc networks, a network coding-enabled new MAC protocol, called NC-MAC protocol, is proposed and its performance is evaluated with a mathematical approach. Numerical results show that this scheme provides conspicuously enhanced system throughput compared to DCF scheme, and more increased system throughput by 48% than rDCF and CO-MAC schemes.

• Proceedings of the KSRS Conference
• /
• 2002.10a
• /
• pp.844-849
• /
• 2002

A provision of spatial information is expected to make a market explosion in various fields. A distribution of spatial data on wireless mobile environments indicates a huge expansion of mobile technology as well as a spread of geospatial applications. For high quality spatial information, 4S technology project integrating 4 kinds of spatial systems is currently being executed with the goal of nationwide integration of spatial data and spatial information systems. In terms of network environments, a mobile ad hoc network where mobile terminals communicate with each other without any infrastructures has been standardized for the next generation mobile wireless network. With respect to the future technologies for spatial information, it is necessary to design 4S applications on mobile ad hoc networks. This paper addresses the issue, which is proposing design points for distributing 4S spatial data on mobile ad hoc networks and ad hoc styled 4S applications.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.9 no.1
• /
• pp.95-101
• /
• 2005

In this paper, some performance characteristics of multimedia traffic for mobile ad-hoc networks is studied with simulations. Synthetic streaming video is considered as the multimedia traffic for MPEG-coded video in the simulation. The synthetic video stream is generated with a video stream generation algorithm. The algorithm generate VBR traffics for MPEG video streams with special predefined GOP(group of pictures) patterns that is consisted of a sequence of I(intra-coded), P(predicted-coded) and B(bidirectional-coded) frames. The synthetic VBR streams is transmitted through UDP protocol with on-demand mobile ad-hoc network routing protocols like as AODV and DSR. And performances for video streams through mobile ad-hoc networks is evaluated, the throughputs is compared between data and video traffics.

• Journal of Advanced Navigation Technology
• /
• v.12 no.3
• /
• pp.233-238
• /
• 2008

Recently, network component become to follow wireless and mobile network from wired network proposed that many TCP algorithm optimized in variety environment. When TCP was created, however as it was design based on wired link, wireless link made more transmission error than wired link. Transmission errors are more frequent and may be incorrectly regarded as indications of network congestion. In this paper, it conduct how effect congestion control algorithm in Mobile ad-hoc network and compare traffic of TCP-Tahoe, TCP-Reno, TCP-New-Reno and TCP-Vegas in Mobile ad-hoc environment.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.05a
• /
• pp.203-207
• /
• 2003

Mobile Ad Hoc Network is a kind of network technology, that mobile hosts can compose networks freely and temporarily where the base networks don't exist and where its establishment is difficult or as occasion demands. Ubiquitous computer network is prograssing in the forms of miniaturization, lightweight or portability. So far, MANET was studied in the point how to route it efficiently, but its power saving problems are been issuing nowadays. We try to not only compare and analyze power saving protocols in multi-hop Ad Hoc network but also present their efficiencies in this thesis.

• The Journal of the Korea Contents Association
• /
• v.11 no.6
• /
• pp.26-32
• /
• 2011

Recently, in the U-health area, there are research related on monitoring brainwaves in real-time for coping with emergent situations like the fatigue driving, cerebral infarction or the heart attack of not only the patients but also the normal elderly folks by transmitting of the EEG(Electroencephalograph). This system could be applied to hospitals or sanatoriums. In this paper, it is applied for the vehicular ad-hoc network to prevent the car accident in advance by monitoring the brainwaves of a driver in real-time. In order to do this, I used mobile ad-hoc nodes supported in the Opnet simulator for the efficient EEG brainwave transmission in the VANET environment. The vehicular ad-hoc networks transmitting the brainwaves to the nearest road-side unit are designed and simulated to draw an efficient and proper vehicular ad-hoc network environment.

• The Journal of the Korea Contents Association
• /
• v.7 no.4
• /
• pp.39-48
• /
• 2007

Ad hoc network is a wireless network without fixed base stations or any wired backbone infrastructure. In the DUDMAC protocol, ORTS and OCTS in control channel solve the problem of deafness and DDATA and DACK in data channel improve spatial reuse by using the efficient blocking algorithm for directional antennas. In this paper, we propose the PCDUDMAC (Power Controlled DUDMAC) protocols. In the PCDUDMAC protocol, the power control of DATA/DACK in data channel saves transmission power and improves spatial reuse. We confirm the throughput performance of the proposed MAC protocol by computer simulations using Qualnet ver.3.8 simulator.

• Journal of Korea Multimedia Society
• /
• v.8 no.1
• /
• pp.62-70
• /
• 2005

In this paper, we present an architecture for supporting QoS multicast routing in mobile ad-hoc networks. The proposed architecture consists of three parts as follows. The first part is a mobility-based clustering as underlying structure for supporting stable multicast services. In the second part, a framework which can support and evaluate the stability of route and network for supporting QoS routing is presented. In the third part, we describe a method which uses two structures of the first and second parts for supporting QoS multicast routing services. The performance evaluation of our proposed architecture is accomplished via modeling and simulation using the Optimized Network Engineering tool(OPNET).