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wireless-sensor-networks
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Cooperative Data Aggregation in Wireless Sensor Networks
, M.Sc. Thesis Sharif University of Technology ; Movaghar, Ali (Supervisor)
Abstract
Minimizing energy consumption is the most important concern in wireless sensor networks (WSNs). Cooperative multiple-input multiple-output (MIMO) and data aggregation are two promising techniques to conserve energy in network nodes by coordinating their transmissions through cooperative communications along with eliminating the inherent redundancy of raw data for transmissions. In this thesis, with the goal of reducing energy consumption, we present a dynamic clustering framework for combined used of cooperative MIMO and data aggregation in cluster-based WSNs. We derive a new and more general energy model for computing energy consumption of cooperative data aggregation in wireless sensor...
A Cluster-Head Election Technique for Data Aggregation in Wireless Sensor Networks
, M.Sc. Thesis Sharif University of Technology ; Movaghar, Ali (Supervisor) ; Manzouri, Mohammad Taghi (Supervisor)
Abstract
Energy constraint is the most critical problem in wireless sensor networks (WSNs). To address this issue, clustering has been introduced as an efficient way for data aggregation and routing. However, there also exist some disadvantages associated with the clustering scheme, such as additional overheads during the cluster-head election and cluster formation process. Most available clustering algorithms do not efficiently take into consideration the geographical information of nodes in the cluster-head election. This leads to uneven distribution of cluster-heads and unbalanced cluster sizes, which brings about uneven energy dissipation in clusters. In this research, an Efficient Distributed...
A QoS-Aware Routing Algorithm in Wireless Multimedia Sensor Network Using Cross-Layer Information
, M.Sc. Thesis Sharif University of Technology ; Khansari, Mohammad (Supervisor)
Abstract
In this thesis, we propose a QoS-aware routing algorithm for multimedia streaming that uses cross-layer information (application layer and physical layer) in Wireless Multimedia Sensor Networks (WMSN). Our goal is to use cross-layer information to route video packets efficiently and deliver a higher quality video in streaming applications. Our QoS-Aware Multi-Path Selection (QAMPS) method is based on multi-path multi-priority selection algorithm that uses Two-Phase geographic Greedy Forwarding (TPGF) as a routing algorithm. The proposed method guarantees QoS by splitting video streams into I-frames, P-frames and B-frames in the application layer and passes them to the network layer for...
Design and Implementation of a Fault-Tolerant Routing Algorithm in WSNs
, M.Sc. Thesis Sharif University of Technology ; Miremadi, Ghasem (Supervisor)
Abstract
Wireless Sensor Networks (WSNs) are prone to faults due to battery depletion of nodes, where a node failure can disturb routing, as it plays a key role in transferring sensed data to the end users. A WSN may be partitioned into groups of nodes called clusters; for every cluster, there is a node, called Cluster Head (CH) that is responsible for collecting and transferring data from all nodes in that cluster. This means that the CH is a single point of failure; i.e., once a CH fails, the whole cluster will fail, which leads to inability of its members for transferring data outside the cluster. This thesis presents a Fault-Tolerant and Energy-Aware algorithm (FTEA), which prolongs the lifetime...
Increasing Life Time of Wireless Sensor Networks
, M.Sc. Thesis Sharif University of Technology ; Hemmatyar, Afshin (Supervisor) ; Hajsadeghi, Khosro (Supervisor)
Abstract
A large number of sensors are spread for monitoring of an area in a random manner. The aim is to have an efficient design for energy that can protect the coverage of the area. A number of sensor nodes that have high density and which are in the area have the duty of monitoring of the area. The aim of this process is to determine of maximum number of separate collections that they have a direct influence upon the life span of the network. The idea behind this approach is that the nodes in areas with low availability are less used as a data routing as well as nodes that have remaining energy. In order to reach this objective, the importance of each sensor node for its duty of protecting...
Localization Optimization: A Customized Cuckoo approach on DV-Hop Algorithm
, M.Sc. Thesis Sharif University of Technology ; Hemmatyar, Ali Mohammad Afshin (Supervisor) ; Mazinani, Majid (Supervisor)
Abstract
Node localization is an important issue in dynamic environments for location-dependent applications of Wireless Sensor Networks (WSNs). Geographical location information is necessary in many WSN applications. The goal of localization algorithm is to assign geographical coordinates to each unknown node position. Among different localization algorithms, DV-hop is one of the well- known algorithms. DV-hop algorithm is a range-free algorithm and has significant error in node location estimation. Since the node deployment is stochastic, minimizing this error has a critical role in location estimation accuracy of the algorithm. Increasing communication radius and number of anchors, to the certain...
Energy Conserving in WSNs Using Network Coding
, M.Sc. Thesis Sharif University of Technology ; Manzuri Shalmani, Mohammad Taghi (Supervisor)
Abstract
Nowadays Wireless Sensor Networks are used in different situations such as greenhouse, agriculture, military applications and etc. The problem of Wireless Sensor Network is that the sensor nodes have limited the energy source. Besides, the power source of sensor nodes is not rechargeable or replaceable. So, one of the main challenges in Wireless Sensor Networks is saving energy. Whereas, most power is consumed due to transmissions, recently a lot of activities have been accomplished in order to reduce transmission times. In this thesis we have focused on a network coding method which is called Sensecode. Sensecode is a technique for reducing communications between nodes. Actually network...
A Multi-channel Scheme for Fast Data Collection in Wireless Sensor Networks
, M.Sc. Thesis Sharif University of Technology ; Hemmatyar, Ali Mohammad Afshin (Supervisor)
Abstract
With the development of technology and growing interest in using high performance and low price products, Wireless Sensor Networks (WSNs) are being dramatically deployed as an emerging technology. The main concern in WSNs is energy consumption that has an effect on sensor’s life time. In order to minimize the energy consumption, Data aggregation, which obtains aggregated values from WSNs, is an important functionality but yet time consuming. On the other hands, Emerging applications of Wireless Sensor Networks (WSNs) such as real-time detection of events need high-rate data collection, which is now an important challenge in WSNs. Multi-channel communication is one of the efficient methods to...
Designing and Implementing a Cluster-based Energy-aware Routing Algorithm for Wireless Sensor Network
, M.Sc. Thesis Sharif University of Technology ; Miremadi, Ghasem (Supervisor)
Abstract
Wireless Sensor Networks (WSNs) consist of sensor nodes that are connected to each other and are widely used in many applications to acquire and process information. WSN nodes are battery powered, therefore energy management is a key factor for long live network. Node radio transceiver unit uses the most part of energy resource of the node and as a result limits the network lifetime. One way to prolong lifetime of network is to utilize routing protocols to manage energy consumption. To have an energy efficient protocol, we can apply cluster organization on the network, where sensor nodes are partitioned into groups called cluster. Then, the whole cluster data is sent through Cluster Head...
Energy-Efficient Reliable Data Aggregation in Wireless Sensor Neworks
, M.Sc. Thesis Sharif University of Technology ; Hemmatyar, Ali Mohammad Afshin (Supervisor)
Abstract
Data aggregation is an efficient method to conserve energy by reducing packet transmissions in Wireless Sensor Networks. However, providing end-to-end data reliability is a major challenge when the network uses data aggregation. In this case a packet loss can miss a complete subtree of values, so greatly affect final results. Data transmission in multiple paths can tolerate this problem, but it may incur some computational error for duplicate-sensitive aggregates when aggregating individual sensor values multiple times. In this thesis, we have proposed a reliable data Aggregation protocol which uses the available path redundancy to deliver a correct aggregate result to the sink with a high...
Analyzing the Energy Consumption of Error Control Mechanisms in Wireless Sensor Networks
, M.Sc. Thesis Sharif University of Technology ; Beigy, Hamid (Supervisor)
Abstract
Nowadays wireless technology is widespread all over the world, because of extensive and successful application of low cost, low power, multifunctional tiny sensor nodes that can be grouped to make up of a wireless sensor network (WSN). Some of Wireless sensor network technologies include Zigbee, EnOcean, Personal area network, Ultra-Wideband and Bluetooth which this thesis focuses on the last one. Scalability, mobility, reliability and energy efficiency are some of the requirements and challenges of WSNs, which among them reliability and reducing energy consumption are two important objectives in wireless sensor networks. Since each sensor node has limited energy to consume, overcoming the...
Data Recovery Analysis of Real-Time Sensor Networks
, M.Sc. Thesis Sharif University of Technology ; Jahangir, Amir Hossein (Supervisor)
Abstract
There are several applications of wireless sensor networks wherein the data collected by the sensors in the network are critical and hence have to be reliably transported to the sink, example of such applications are fire detection in a forest or controlling vibration on body of dam. Reliable communication in wireless sensor networks is hard to achieve efficiently using methods in conventional systems like Internet. End-to-end retransmission is inefficient, or in some cases impossible. It is well-known that Reed-Solomon codes may be used to provide error correction for multiple failures in RAID-like systems. To the coding theorists, this technique is a straight forward extension to a basic...
Mutual_effect Evaluation of Energy Consumption and Realtimeness in Wireless Sensor Networks
, M.Sc. Thesis Sharif University of Technology ; Jahangir, Amir Hossein (Supervisor)
Abstract
Nowadays Wireless Sensor Networks (WSNs) are found in a variety of applications such as environmental monitoring, military surveillance and medical systems. These applications interface with the real world environments and the delivery of data is subject to certain timing constraints. Most of the protocols being used in the WSNs do not satisfy real-time requirements and only deliver data in a best-effort fashion. However, real-time support in the WSNs remains an open research topic. This dissertation first studies real-time application and then real-time approaches in WSNs. Real-time applications are applications that require bounded service time. Normally in WSNs, communication delays are...
Data Reduction and Aggregation in Wireless Sensor Networks
, M.Sc. Thesis Sharif University of Technology ; Movaghar Rahimabadi, Ali (Supervisor)
Abstract
Data transmission consumes most of the power resources in wireless sensor networks. Con-sequently, a large number of methods have been devised to cope with this problem. In this thesis, we propose a data reduction algorithm based on the transmission workload of interme-diate nodes. We aggregate the incoming packets to the intermediate nodes into one packet by employ ing the Principal Component Analysis (PCA). Therefore, each intermediate node only sends one packet in stead of relaying all the incoming packets and hence we achieve consid-erable reduction in power consumption at those nodes. Although this approach imposes some delay for buffering the incoming packets, but extending the...
Reduction of Energy Consumption in Wireless Sensor Networks Using Genetic Algorithm
, M.Sc. Thesis Sharif University of Technology ; Hemmatyar, Ali Mohammad Afshin (Supervisor)
Abstract
Reducing energy consumption is one of the challenges facing wireless sensor networks with many solutions introduced for them with each having advantages and disadvantages. Some of the solutions introduced are based on using movable sinks. In this project, we attempt at proposing a place for the establishment of sinks using genetic algorithm that can reduce energy consumption in the net knots and increase the net life. This work should be done after reviewing the results of past researches and introduced methods. We will analyze the practicality of the proposed model using simulation and will show their advantages over the previous mentioned methods
Optimum hello interval for a connected homogeneous topology in mobile wireless sensor networks
, Article Telecommunication Systems ; Vol. 52, issue. 4 , April , 2013 , pp. 2475-2488 ; Online ISSN: 1572-9451 ; Sarbazi-Azad, H ; Sharif University of Technology
Abstract
Topology of a mobile wireless sensor/ad hoc network is prone to link breakages due to node mobility which compels the periodic re-construction of the topology in so called ""hello"" intervals. The problem addressed in this paper is determining the maximum ""hello"" interval preserving the connectivity of a homogeneous topology with high probability. In order to study the optimum ""hello"" interval, statistical topology lifetime (STL) is formally defined as a value of ""hello"" interval that ensures statistical connectivity with a given threshold. Temporal properties of the topology are studied based on two phenomena; one concerning a connectivity phase transition with time and the other one...
MC-MLAS: Multi-channel Minimum Latency Aggregation Scheduling in Wireless Sensor Networks
, Article Computer Networks ; Volume 57, Issue 18 , December , 2013 , Pages 3812-3825 ; 13891286 (ISSN) ; Yousefi, H ; Afshin Hemmatyar, A. M ; Movaghar, A ; Sharif University of Technology
2013
Abstract
Data aggregation is a key, yet time-consuming functionality in wireless sensor networks (WSNs). Multi-channel design is a promising technique to alleviate interference as a primary reason for long latency of TDMA aggregation scheduling. Indeed, it provides more potential of parallel transmissions over different frequency channels, thus minimizing time latency. In this paper, we focus on designing a multi-channel minimum latency aggregation scheduling protocol, named MC-MLAS, using a new joint approach for tree construction, channel assignment, and transmission scheduling. To our best knowledge, this is the first work in the literature which combines orthogonal channels and partially...
Energy aware data compression in WSN
, Article Lecture Notes in Electrical Engineering ; Volume 152 , 2013 , Pages 673-682 ; 18761100 (ISSN) ; 9781461435341 (ISBN) ; Manzuri, M. T ; Sharif University of Technology
2013
Abstract
Wireless sensor networks (WSNs) use energy for their sensing, computation, and communication. To increase the lifetime of the network, sensor nodes are equipped with energy storage devices. Recharging of their batteries is not possible in most applications. Therefore, energy consumption needs to be monitored and limited to increase the energy consumption performance of the network. The communication module uses the highest amount of energy in a WSN. Among several methods offered to reduce the energy consumption, data compression has the highest effect on the energy usage by reducing the number of bits to be broadcasted. This paper illustrates an energy consumption reduction in WSN by...
On the better performance of ADMR versus ODMRP
, Article 2012 6th International Symposium on Telecommunications, IST 2012 ; 2012 , Pages 621-625 ; 9781467320733 (ISBN) ; Khansari, M ; Sharif University of Technology
2012
Abstract
This paper presents a comparative performance analysis in more realistic scenario and more performance metrics of ADMR and ODMRP, two on-demand multicast routing protocols for Mobile Ad hoc Networks (MANETs) and Wireless Sensor Networks (WSNs). There are a few comparison works done between two multicast Ad hoc routing protocols, ADMR and ODMRP; these works are not complete in terms of both performance metrics and realistic scenarios. Simulation results show an unusual low number of control packets transmitted per data packet delivered in ADMR, this low number of control packet transmitted per data packet in ADMR has caused some comparison works to judge to better performance of ADMR than...
S-NC: Structure-free network coding-aware routing in wireless sensor networks
, Article MSWiM'12 - Proceedings of the 15th ACM International Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems ; 2012 , Pages 403-407 ; 9781450316286 (ISBN) ; Yousefi, H ; Movaghar, A ; Sharif University of Technology
2012
Abstract
Network Coding (NC) is an emerging technique that helps wireless networks to have higher throughput and better energy efficiency. In this paper, a novel network coding-aware routing (S-NC) which uses NC to improve reliability and robustness in unreliable WSNs is proposed. It is based on a structure-free routing algorithm as the underlying routing engine which employs neighbor queue length to increase coding opportunity; while exploiting a spatial coding method to control the amount of redundancy. To the best of our knowledge, this is the first study on the topic of network codingaware routing in Wsns. Simulation results in Tossim demonstrate that S-NC significantly improves the performance...