Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Subject: search.filters.subject.Wireless sensor networks

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Now showing 1 - 9 of 9
  • Article
    Citation - WoS: 15
    Citation - Scopus: 21
    Tracking Fast Moving Targets in Wireless Sensor Networks
    (Institution of Electronics and Telecommunication Engineers, 2010) Alaybeyoğlu, Ayşegül; Erciyeş, Kayhan; Kantarcı, Aylin; Dağdeviren, Orhan
    We propose a dynamic distributed algorithm for tracking objects that move fast in a sensor network. In the earlier efforts in tracking moving targets, the current leader node at time t predicts the location only for time t + 1 and if the target moves in high speed, it can pass by a group of nodes very fast without being detected. Therefore, as the target increases its speed, the probability of missing that target also increases. In this study, we propose a target tracking system that predicts future k locations of the target and awakens the -corresponding leader nodes so that the nodes along the trajectory self organize to form the clusters to collect data related to the target in advance and thus reduce the target misses. The algorithm first -provides detection of the target and forms a cluster with the neighboring nodes around it. After the selection of the cluster leader, the coordinates of the target is estimated using localization methods and cooperation -between the cluster nodes under the control of the leader node. The coordinates and the speed of the target are then used to estimate its trajectory. This information in turn provides the location of the nodes along the estimated trajectory which can be awaken, hence providing tracking of the moving object. We describe the algorithm, analyze its efficiency and show by simulations that it performs well to track very fast moving objects with speeds much higher than reported in literature.
  • Conference Object
    Citation - WoS: 4
    Citation - Scopus: 3
    On Exploiting Spatial Correlation for Energy Harvesting Wireless Sensor Networks
    (Institute of Electrical and Electronics Engineers Inc., 2017) Al-Qamaji, Ali; Atakan, Barış
    Wireless Sensor Network (WSN) is a set of inexpensive densely deployed sensor nodes with limited functionalities and scarcity in energies. The observations of sensors are forwarded directly to the Base Station (BS). In densely deployed sensors, sensing data are likely to be highly correlated in space domain, which produces unfavorable redundant readings and wasting in energy. In this paper, we propose an Event Distortion-Based Node Selection (EDNS) algorithm which exploits spatial correlation for reducing inessential sensor nodes that have correlated readings for improving Energy-Efficiency (EE) with acceptable distortion level. Furthermore, we derive a theoretical framework of distortion function for single-hop communication model to observe the advantages from energy harvesting to the accuracy level. Furthermore, the trade-off between energy consumption and distortion level is investigated.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 21
    A Survey of Agent Technologies for Wireless Sensor Networks
    (Medknow Publications and Media, 2011) Dagdeviren, Orhan; Korkmaz, İlker; Tekbacak, Fatih; Erciyeş, Kayhan
    Wireless sensor networks (WSNs) do not have a fixed infrastructure and consist of sensor nodes that perform sensing and communicating tasks. The WSNs have large application spectrum such as habitat monitoring, military surveillance, and target tracking, where sensor nodes may operate distributed in highly dynamic environments. Battery-constrained sensor nodes may aggregate the sensed data, localize themselves, and route the packets in an energy-efficient and decentralized manner to enable running the applications. Agents are capable of independent and autonomous action, so that they can successfully carry out tasks that have been delegated to them, thus agent-based approaches are very suitable to apply as the solution of the problems occurring in WSNs. So far many agent-based approaches were proposed for WSNs. This paper surveys the agent technologies for sensor networks by providing a classification, objectives and costs of these approaches with the open research problems. To the best of our knowledge, this is the first study that covers the intersection of the agent technology and sensor networks from a wide perspective.
  • Conference Object
    Citation - Scopus: 2
    Adaptive Bit Partitioning Strategy for Cell-Edge Users in Multi-Antenna Multicell Networks
    (Institute of Electrical and Electronics Engineers Inc., 2011) Özbek, Berna; Le Ruyet, Didier
    In this paper, we improve the performance of cell-edge users by applying adaptive bit partitioning for intercell interference cancelation in cooperative downlink multicell systems. The strategy for partitioning quantization bits between serving and interfering base stations affects the performance of the cooperative networks which is quite sensitive to the quality of the channel state information. The existing transmission strategies are based on the maximization of average cell rate which results in a reduced rate for the users in the cell-edge regions. We propose an adaptive bit partitioning strategy to improve the rate of cell-edge users at the same average feedback link rate. We show the performance of the cell-edge users is significantly increased while keeping the same average cell rate. © 2011 IEEE.
  • Conference Object
    Citation - Scopus: 5
    A Distributed Wakening Based Target Tracking Protocol for Wireless Sensor Networks
    (Institute of Electrical and Electronics Engineers Inc., 2010) Alaybeyoğlu, Ayşegül; Dağdeviren, Orhan; Kantarcı, Aylin; Erciyeş, Kayhan
    We propose a two layer protocol for tracking fast targets in sensor networks. At the lower layer, the Distributed Spanning Tree Algorithm (DSTA) [12] partitions the network into clusters with controllable diameter and constructs a spanning tree backbone of clusterheads rooted at the sink. At the upper layer, we propose a target tracking algorithm which wakes clusters of nodes by using the estimated trajectory beforehand, which is different from existing studies [3] in which target can be detected only when the nodes close to the target are awake. We provide the simulation results and show the effect of fore-waking operation by comparing error and miss ratios of existing approaches with our proposed target tracking algorithm. © 2010 IEEE.
  • Conference Object
    Citation - WoS: 13
    Citation - Scopus: 14
    Performance Evaluation of Cluster-Based Target Tracking Protocols for Wireless Sensor Networks
    (Institute of Electrical and Electronics Engineers Inc., 2009) Alaybeyoğlu, Ayşegül; Dağdeviren, Orhan; Erciyeş, Kayhan; Kantarcı, Aylin
    Target tracking is an important application type for wireless sensor networks (WSN). Recently, various approaches [1-11] are proposed to maintain the accurate tracking of the targets as well as low energy consumption. Clustering is a fundamental technique to manage the scarce network resources [12-19]. The message complexity of an application can be significantly decreased when it is redesigned on top of a clustered network. Clustering has provided an efficient infrastructure in many existing studies [1-8]. The clusters can be constructed before the target enters the region which is called the static method [1-4] or clusters are created by using received signal strength (RSS) from target which is called the dynamic method [5-8]. In this paper we provide simulations of static and dynamic clustering algorithms against various mobility models and target speeds. The mobility models that we applied are Random Waypoint Model, Random Direct Model and Gauss Markov Model. We provide metrics to measure the tracking performance of both approaches. We show that the dynamic clustering is favorable in terms of tracking accuracy whereas the energy consumption of static clustering is significantly smaller. We also show that the target moving with Gauss Markov Model can be tracked more accurately than the other models.
  • Conference Object
    Citation - WoS: 13
    Citation - Scopus: 12
    Distributed Algorithms To Form Cluster Based Spanning Trees in Wireless Sensor Networks
    (Springer Verlag, 2008) Erciyeş, Kayhan; Özsoyeller, Deniz; Dağdeviren, Orhan
    We propose two algorithms to form spanning trees in sensor networks. The first algorithm forms hierarchical clusters of spanning trees with a given root, the sink. All of the nodes in the sensor network are then classified iteratively as subroot, intermediate or leaf nodes. At the end of this phase, the local spanning trees are formed, each having a unique subroot (clusterhead) node. The communication and data aggregation towards the sink by an ordinary node then is accomplished by sending data to the local subroot which routes data towards the sink. A modified version of the first algorithm is also provided which ensures that the obtained tree is a breadth-first search tree where a node can modify its parent to yield shorter distances to the root. Once the sub-spanning trees in the clusters are formed, a communication architecture such as a ring can be formed among the subroots. This hybrid architecture which provides co-existing spanning trees within clusters yields the necessary foundation for a two-level communication protocol in a sensor network as well as providing a structure for a higher level abstraction such as the γ synchronizer where communication between the clusters is performed using the ring similar to an α synchronizer and the intra cluster communication is accomplished using the sub-spanning trees as in the β synchronizers. We discuss the model along with the algorithms, compare them and comment on their performances.
  • Conference Object
    Citation - Scopus: 38
    On the Ieee 802.15.4 Mac Layer Attacks: Gts Attack
    (Institute of Electrical and Electronics Engineers Inc., 2008) Sokullu, Radosveta; Dağdeviren, Orhan; Korkmaz, İlker
    In the last several years IEEE 802.15.4 [1] has been accepted as a major MAC layer protocol for wireless sensor networks (WSNs) and has attracted the interest of the research community involved in security issues as the increased range of application scenarios bring out new possibilities for misuse and taking improper advantage of sensor nodes and their operation. As these nodes are very resource restrained such possible attacks and their early detection must be carefully considered. This paper surveys the known attacks on wireless sensor networks, identifies and investigates a new attack, Guaranteed Time Slot (GTS) attack, taking as a basis the IEEE 802.15.4 MAC protocol for WSN. The GTS Attack is simulated with different scenarios using ns-2 and the results are evaluated both from the point of view of the attacked and the attacker.
  • Conference Object
    Citation - WoS: 7
    Citation - Scopus: 12
    Time Synchronization Algorithms Based on Timing-Sync Protocol in Wireless Sensor Networks
    (Institute of Electrical and Electronics Engineers Inc., 2008) Kulaklı, Ali Burak; Erciyeş, Kayhan
    Wireless Sensor Networks(WSN) are large scale networks of sensors running on wireless environment. For an application running on a WSN, gathered data by the sensors are time critical in most of the cases. However, almost all the nodes suffer from a problem named clock drift. This problem causes clock difference among nodes as time goes because the processors do not run exactly at the same speed. There are many proposed solutions to remedy this problem. TPSN (Timing-sync Protocol for Sensor Networks) is one of the effective protocols proposed to synchronize sensor networks. In this paper, we propose enhancements over TPSN to synchronize nodes in a wireless sensor network more effectively with a lower message complexity and higher precision.