• 대한임베디드공학회논문지
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• 제1권2호
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• pp.37-42
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• 2006

In this paper, we study a problem of providing reliable data transmission in wireless sensor network(WSN). A system with forward error correction9FEC) can provide an objective reliability while using less transmission power than a system without FEC. We propose the use of LDPC codes of various code rate (0.53, 0.81, 0.91) of FEC for WSN. Node-node-node interference is considered in the simulation in addition to AWGN in the channel. It is shown that the rate of 0.91 LDPC coded system obtained 7dB gain in signal to noise ratio over a system without FEC.

• 전기학회논문지P
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• 제66권4호
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• pp.229-235
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• 2017

Until now, a study on a ubiquitous sensor network has been mainly concentrated in the areas of sensor nodes, and as a results, technologies related with sensor node were greatly developed. Despite of many achievements on research and development for a sensor node, a ubiquitous sensor network may failed to establish the actual service environment because variety of restrictions. In order to provide a actual service using a ubiquitous sensor networks applied to many results on research and development for a sensor nodes, a study on a wired/wireless composite router must be carried out. However a study on a wired/wireless composite router is relatively very slow compared with the sensor node. In this study, developed a high-performance router platform supporting IPv6 that can provide high-speed wired/wireless interface and QoS, and it can provide the multimedia service Interlocking the wireless sensor network and the Internet network. To analysis a given network environment and to develop the appropriate hardware and software in accordance with this requirement.

• 센서학회지
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• 제25권5호
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• pp.371-376
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• 2016

A self-powered piezoelectric energy harvester was developed for the application in wireless sensor node. The energy harvester was evaluated with power generation characteristics for the wireless sensor node for structural diagnosis of the electric power system. The self-powered wireless sensor node was set to measure temperature, vibration frequency of the electric power system. A piezoelectric harvester composed of 7 uni-morph cantilevers (functionalized as 6 generators and 1 vibration sensor) was connected to be an array and revealed to produce significantly high output power of approximately 10 mW at 120 Hz under 3.4 g((1 g = $9.8m/sec^2$). The wireless sensor node could work as the electric power generated by the developed piezoelectric harvester.

• 한국전자통신학회논문지
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• 제7권6호
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• pp.1337-1342
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• 2012

최근 몇 년간, 홈 네트워킹에 관한 많은 연구가 활발히 진행되고 있다. 홈 네트워킹을 위한 대부분의 기술들은 유선을 기반으로 하지만, 무선 연결을 위한 기술도 필요하다. 본 논문은 홈 네트워크 분야 중에서 무선 네트워크에 초점을 맞추고 있다. 무선 LAN, 블루투스, HomeRF와 같은 많은 무선 통신 기술중에서, 본 논문은 특히 무선 센서 네트워크라는 새로운 기술을 무선 홈네트워크에 적용하는 것을 제안한다. 본 논문은 무선 센서 노드와 무선 센서 네트워크를 위한 하드웨어 및 프로토콜 스택 설계시 필요한 고려 사항을 제시하고, 홈 네트워킹에 무선 센서 네트워크를 적용하기 위한 방법과 다양한 센서 노드로 무선 홈 네트워킹을 구성하는 방법을 제시한다. 마지막으로, 본 논문은 자체적으로 설계된 무선 센서 노드 시스템을 소개하고 이 글을 맺는다.

• 한국통신학회논문지
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• 제35권5B호
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• pp.833-839
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• 2010

최근 무선 센서 네트워크 (Wireless Sensor Network)에서 Actor Network 등의 이동성이 있는 센서에 대한 연구가 매우 활발하게 진행되고 있다. 그러나 기존의 대부분의 센서 간의 인증 및 키 교환 기술에 대한 연구는 고정된 센서만 있는 환경만을 고려하고 있으며, 이동성이 있는 센서 노드가 있는 환경에 적용하는 경우 통신 및 연산 부하가 급증하기 ��문에, 자원 제약이 있는 센서 네트워크 환경에서 적용하기 부적합하다. 따라서 본 논문을 통해 최초 인증 이후 재인증 시 자원 이용을 최소화 할 수 있는 이동성이 있는 센서 환경에 적합한 효율적인 센서 인증 및 키 교환 기술을 제안한다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.845-848
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• 2008

무선 센서 네트워크를 이용한 어플리케이션을 테스트할 경우 무선 센서 노드의 전원 공급, 설치 및 배포, 유지 보수 및 디버깅에 어려움이 있다. 따라서 무선 센트 네트워크 기반의 어플리케이션의 효율적인 개발과 유지 보수를 위해서는 시뮬레이터가 필수적으로 필요하다. 그러나 기존의 무선 센서 네트워크 시뮬레이터들은 무선 네트워크 구성과 유지에 관련된 MAC 주소 배분, 라우팅, 전원 관리 측면을 주요한 테스트 요소로 보았기 때문에 싱크 노드를 통하여 사료를 수집하고 처리하는 호스트 어플리케이션의 기능을 테스트하기에 부적합하다. 본 연구에서는 싱크 노드와 연결된 호스트에서 동작하는 어플리케이션을 테스트할 수 있도록 무선 센서 네트워크 상에서 전달되는 전문을 로깅하고 시뮬레이터에서 전문을 조회하여 테스트 할 수 있는 로그 기반의 무선 센서 네트워크 시뮬레이터 제안하고 설계 및 구현하였다.

• Journal of information and communication convergence engineering
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• 제7권3호
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• pp.258-262
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• 2009

A Practical application of environmental monitoring system based on wireless sensor node network with the core of embedded system STR711FR2 microprocessor is presented in the paper. The adaptable and classifiable wireless sensor node network is used to achieve the data acquisition and multi-hop wireless communication of parameters of the monitoring base station environment including repeaters. The structure of the system is proposed and the hardware architecture of the system is designed, and the system operating procedures is proposed. As a result of field test, designed hardware platform operated with 50kbps bit rate and 5MHz channel spacing at 2040Hz. The wireless monitoring system can be managed and swiftly retreated without support of base station environmental monitoring.

• Journal of Electrical Engineering and Technology
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• 제13권6호
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• pp.2447-2455
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• 2018

Security is more important in many sensor applications. The node replication attack is a major issue on sensor networks. The replicated node can capture all node details. Node Replication attacks use its secret cryptographic key to successfully produce the networks with clone nodes and also it creates duplicate nodes to build up various attacks. The replication attacks will affect in routing, more energy consumption, packet loss, misbehavior detection, etc. In this paper, a Secure-Efficient Centralized approach is proposed for detecting a Node Replication Attacks in Wireless Sensor Networks for Static Networks. The proposed system easily detects the replication attacks in an effective manner. In this approach Secure Cluster Election is used to prevent from node replication attack and Secure Efficient Centralized Approach is used to detect if any replicated node present in the network. When comparing with the existing approach the detection ratio, energy consumption performs better.

• ETRI Journal
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• 제33권6호
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• pp.857-863
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• 2011

Due to uncertainties in target motion and randomness of deployed sensor nodes, the problem of imbalance of energy consumption arises from sensor scheduling. This paper presents an energy-efficient adaptive sensor scheduling for a target monitoring algorithm in a local monitoring region of wireless sensor networks. Owing to excessive scheduling of an individual node, one node with a high value generated by a decision function is preferentially selected as a tasking node to balance the local energy consumption of a dynamic clustering, and the node with the highest value is chosen as the cluster head. Others with lower ones are in reserve. In addition, an optimization problem is derived to satisfy the problem of sensor scheduling subject to the joint detection probability for tasking sensors. Particles of the target in particle filter algorithm are resampled for a higher tracking accuracy. Simulation results show this algorithm can improve the required tracking accuracy, and nodes are efficiently scheduled. Hence, there is a 41.67% savings in energy consumption.

• 비파괴검사학회지
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• 제31권3호
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• pp.246-259
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• 2011

This study presents a structural health monitoring (SHM) method for bolted connections by using multi-channel wireless impedance sensor nodes and multiple PZT-interfaces. To achieve the objective, the following approaches are implemented. Firstly, a PZT-interface is designed to monitor bolt loosening in bolted connection based on variation of electro-mechanical(EM) impedance signatures. Secondly, a wireless impedance sensor node is designed for autonomous, cost-efficient and multi-channel monitoring. For the sensor platform, Imote2 is selected on the basis of its high operating speed, low power requirement and large storage memory. Finally, the performance of the wireless sensor node and the PZT-interfaces is experimentally evaluated for a bolt-connection model Damage monitoring method using root mean square deviation(RMSD) index of EM impedance signatures is utilized to estimate the strength of the bolted joint.