• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1666-1668
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• 2004

By wireless transmission data, there is high possibility to get distortion and lose by noise and barrier on wireless. If the data check damaged and lost at receiver, can't make it clear and can't judge whether this data is right or not. Therefore, by wireless transmission data need the data error check algorithm in order to decrease the data's distortion and lose and to monitoring the transmission data as real time. This study consists of RF station for wireless transmission, Water Level Meter station for water level measurement and Error check algorithm for error check of transmission data. This study is also that investigation and search for error check algorithm in order to wireless digital data transmission in condition of the least data's damage and lose. Designed transmitter and receiver with one - chip micro process to protect to swell the volume of circuit. Had designed RF transmitter - receiver station simply by means of ATMEL one - chip micro process in the systems. Used 10mW of the best RF power and 448MHz-449MHz on frequency band which can get permission to use by Frequency Law made by Korean government

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.993-997
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• 2004

A data error inspection algorithm for wireless digital data communication was developed. Original data converted By wireless digital data error inspection algorithm. Wireless digital data is high possibility to get distortion and lose by noise and barrier on wireless. If the data check damaged and lost at receiver, can't make it clear and can't judge whether this data is right or not. Therefore, by wireless transmission data need the data error inspection algorithm in order to decrease the data distortion and lose and to monitoring the transmission data as real time. This study consists of RF station for wireless transmission, Water Level Meter station for water level measurement and Error inspection algorithm for error check of transmission data. This study is also that investigation and search for error inspection algorithm in order to wireless digital data transmission in condition of the least data's damage and lose. Designed transmitter and receiver with one - chip micro process to protect to swell the volume of circuit. Had designed RF transmitter - receiver station simply by means of ATMEL one - chip micro processing the systems. Used 10mW of the best RF power and 448MHz-449MHz on frequency band which is open to public touse free within the limited power.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1255-1261
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• 2010

An operating information and fault recode of train is very important information for safety driving and maintenance. And these information is increased and need high speed as the number of trains is increased. Wireless LAN or CDMA network is efficient to report more complicated and various information from vehicle to server in control center. Existing wireless transmission system has weakness due to transmission system is separated with TDCS and standalone. At first, standalone system needs space to be installed and cost is increased. And data transmission capacity and speed is limited by complicated structure that transmission system receive data thru serial communication like RS232 and then data transmission system send data to server in control center. This article is study to develop embedded & wireless fault code transmission device to be installed in TDCS to overcome weakness of space and to have more cost effective and simple structure. It is adapted 802.11b/g WiFi for wireless communication and OS is used embedded Linux that can easily implement wireless communication environment and ensure TCP/IP communication’s security. We also implement simple server to test wireless communication between embedded & wireless fault code transmission device and server in control center.

• International Journal of Control, Automation, and Systems
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• v.6 no.1
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• pp.119-125
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• 2008

This paper examines the use of a wireless Fieldbus based on IEEE 802.15.4 MAC protocol. The superframe of IEEE 802.15.4 is applied to a transmission scheme of real-time mixed data. The transmission and bandwidth allocation scheme are proposed for real-time communication using a superframe. The proposed wireless Fieldbus protocol is able to transmit three types of data (periodic data, sporadic data, and non real-time messages), and guarantee realtime transmission simultaneously within a limited timeframe.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1145-1150
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• 2008

In this paper, We studied efficient design of wireless transmission system for unified data transmission in a subway and railway. It is increased that need of broadband multimedia service to make useful environment for user and to support the operation of railway system. High bandwidth is better if we need more services. But, high bandwidth requires more cost at tunnel of subway. More bandwidth make receive sensitivity to bad. So it need more wireless Station. We deduced best bandwidth of subway wireless transmission system reflecting the cost of installation and efficiency of system. Consequently, we decide efficient service model of broadband wireless system at a subway. Subway broadband wireless transmission system is tested in this year, and it is to be extended to province subway. Cost of subway broadband wireless transmission system is saved, because the system can be efficiently designed. Therefore, the effectiveness is expected to be very big.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.3
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• pp.32-38
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• 2020

The deployment of geographically distributed wireless sensors has greatly elevated the capability of monitoring structural health in social-overhead capital (SOC) public infrastructures. This paper deals with the utilization of a distributed mobility management (DMM) approach for the deployment of wireless sensing devices in a structural health monitoring system (SHM). Then, a wireless sensing mechanism utilizing low-energy adaptive clustering hierarchy (LEACH)-based clustering algorithm for smart sensors has been analyzed to support the seamless data transmission of structural health information which is essentially important to guarantee public safety. The clustering of smart sensors will be able to provide real-time monitoring of structural health and a filtering algorithm to boost the transmission of critical information over heterogeneous wireless and mobile networks.

• Proceedings of the IEEK Conference
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• 2002.06c
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• pp.47-50
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• 2002

In this paper, the efficient transmission technique of real time video data over 3G wireless networks is presented. To understand the transmission characteristic of 3G networks on real time video data, we implemented the data transport structure of 3G wireless networks. Also this research is based on current 3G wireless network specification of 3GPP, 3GPP2 standard organization to evaluate the result over real 3G wireless network environment. The retransmission by radio link layer results in the delay factor. To implement video data transmission efficiently, we Propose to use both no-retransmission and forward error correction method.

• Smart Structures and Systems
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• v.14 no.4
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• pp.617-641
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• 2014

The energy constraint is still a common issue for the practical application of wireless sensors, since they are usually powered by batteries which limit their lifetime. In this paper, a practical compound energy efficiency strategy is proposed and realized in the implementation of a real time wireless sensor platform. The platform is intended for wireless structural monitoring applications and consists of three parts, wireless sensing unit, base station and data acquisition and configuration software running in a computer within the Matlab environment. The high energy efficiency of the wireless sensor platform is achieved by a proposed adaptive radio transmission power control algorithm, and some straightforward methods, including adopting low power ICs and high efficient power management circuits, low duty cycle radio polling and switching off radio between two adjacent data packets' transmission. The adaptive transmission power control algorithm is based on the statistical average of the path loss estimations using a moving average filter. The algorithm is implemented in the wireless node and relies on the received signal strength feedback piggybacked in the ACK packet from the base station node to estimate the path loss. Therefore, it does not need any control packet overheads. Several experiments are carried out to investigate the link quality of radio channels, validate and evaluate the proposed adaptive transmission power control algorithm, including static and dynamic experiments.

• Journal of Korea Multimedia Society
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• v.18 no.8
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• pp.909-914
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• 2015

In wireless sensor networks, sensor nodes have a short transmission range and data is transferred from source to destination node using the multi-hop transmission. Sensor nodes are powered by battery and the link qualities are different, and the routing protocol in the wireless sensor network is one of the important technical issues. Multipath routing was proposed to reduce the data congestion and increase data throughput. In the multipath routing, however, each path can be interfered by the other path, and it can aggravate network performance. In this paper, we propose the multipath routing scheme for multi-rate wireless sensor networks. The multipath routing selects transmission paths to minimize transmission delay and path interference.

• International Journal of Internet, Broadcasting and Communication
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• v.13 no.3
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• pp.25-33
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• 2021

Energy-harvesting wireless sensor networks(EH-WSNs) can collect energy from the environment and overcome the technical limitations of existing power. Since the transmission distance in a wireless sensor network is limited, the data are delivered to the destination node through multi-hop routing. In EH-WSNs, the routing protocol should consider the power situations of nodes, which is determined by the remaining power and energy-harvesting rate. In addition, in applications such as environmental monitoring, when there are urgent data, the routing protocol should be able to transmit it stably and quickly. This paper proposes an adaptive routing protocol that satisfies different requirements of normal and urgent data. To extend network lifetime, the proposed routing protocol reduces power imbalance for normal data and also minimizes transmission latency by controlling the transmission power for urgent data. Simulation results show that the proposed adaptive routing can improve network lifetime by mitigating the power imbalance and greatly reduce the transmission delay of urgent data.