Ad-hoc Sensor Networks Research Articles

Cognitive Wireless Sensor Network Platform for Cooperative Communications

Nowadays, Wireless Ad Hoc Sensor Networks (WAHSNs), specially limited in energy and resources, are subject to development constraints and difficulties such as the increasing RF spectrum saturation at the unlicensed bands. Cognitive Wireless Sensor Networks (CWSNs), leaning on a cooperative communication model, develop new strategies to mitigate the inefficient use of the spectrum that WAHSNs face. However, few and poorly featured platforms allow their study due to their early research stage. This paper presents a versatile platform that brings together cognitive properties into WAHSNs. It combines hardware and software modules as an entire instrument to investigate CWSNs. The hardware fits WAHSN requirements in terms of size, cost, features, and energy. It allows communication over three different RF bands, becoming the only cognitive platform for WAHSNs with this capability. In addition, its modular and scalable design is widely adaptable to almost any WAHSN application. Significant features such as radio interface (RI) agility or energy consumption have been proven throughout different performance tests.

Modeling and Simulation Analysis of an Efficient MASNET Routeless Routing Protocol

The deployment of wireless ad-hoc mobile sensor network (MASNET) technology proves critical in many civilian and military applications. Routing over MASNET faces many challenges, such as scarce bandwidth, dynamic change of topology, limited computational capabilities, and power budgets of sensor nodes. Hence, we introduced a new routeless routing model that efficiently copes with such challenges, as asserted by initial simulation-obtained results. In this paper we validate our routing protocol via both mathematical modeling and simulation.

IMPROVED ARCHITECTURE FOR MAXIMIZING SYSTEM LIFETIME OF WIRELESS SENSOR NETWORK USING CLUSTERING ALGORITHM

Real time implementation of Ad-hoc Wireless Sensor Network has increased with great potential. Application areas of WSN’s are military warfare, disaster management, battle field, forest fire detection and other several monitoring area. Key challenge in WSN is to minimize the use of limited battery resources. Several energy efficient routing algorithms have been proposed till date. LEACH (Low-Energy Adaptive Clustering Hierarchy), a clustering protocol that divides the network into logical clusters and keeps rotating the cluster head selection to send data to sink. In this paper we propose a new technique of cluster formation based on organizational setup structure. New Network structure proposed will show an efficient increase in minimizing the node energy dissipation of signal transmission and will lead to maximize the system lifetime. We also propose a mix of Round-Robin algorithm into the cluster head selection for data transmission to base station. We compare the newly proposed clustering algorithm with the traditional LEACH algorithm.

A Research to Ad-hoc and Wireless Sensor Network

In the current wireless network technology, the most important research is Ad-hoc, and the most promising is the WSN. Ad-hoc which develops on the basis of packet radio network is a wireless mobile network with self-organizing, peer to peer and multi-hop. WSN combines Ad-hoc and sensor technology to collaboratively perceive, collect and process the message of sensing objects in the coverage area of network, and send to the viewer.

Comparison of different Energy Minimization Techniques in Wireless Sensor Network

Wireless Sensor Networks (WSN) is a set of sensor nodes that collects the information from environment and sends to the base station (Header node or Central Node).Wireless range of applications related to national security, surveillance, home and office application[1],habitat monitoring[2,3],health application[4,5],environment forecasting[6] and military etc. One important class of WSNs is wireless Ad-Hoc sensor networks, characterized by an Ad-Hoc or random sensor deployment method, where the sensor location is not known a priori. This applies when individual sensor placement is infeasible, such as in battlefields or in disaster areas. Generally, more sensors are deployed than required (As compared with the optimal placement) to perform the proposed task; this compensates for the lack of exact positioning and improves fault tolerance. The characteristics of a sensor network include limited resources, large and dense networks, and a dynamic topology. An important issue in sensor networks is power scarcity, driven in part by battery size and weight limitations. Mechanisms that optimize sensor energy utilization have a great impact on prolonging the network lifetime. In this paper different energy minimization techniques have been compared that are used in wireless sensor network.

Clustering Based on Node Density in Heterogeneous Under-Water Sensor Network

An underwater sensor network comprise of sensors and vehicles to perform numerous tasks. In underwater ad-hoc sensor network acoustic signals are transmitted through multi-hop sequence so as to save sensors' energy and to achieve longer life time. Re- charging batteries of deep water deployed sensors is practically not feasible. Clustering is the best strategy to achieve efficient multi-hopping, where cluster head is made responsible to collect local data and forward it to the sink. Cluster-head selection is the challenging job in a cluster, as it loses its energy in transmitting its own data and aggregated data, as compared to other sensors. In this paper we have proposed an Under Water Density Based Clustered Sensor Network (UWDBCSN) scheme using heterogeneous sensors. The scheme utilizes two types of sensors: one having high energy capacity, working as cluster head, having small quantity and other are ordinary sensors in huge quantity. Further cluster-head selection is based on node degree i.e. the density of the sensors in a region. The proposed scheme is found to be more energy efficient helps in extending the life time of underwater sensor networks.

Dynamic Traffic Energy Efficient Topology Based Routing Protocol for Wireless Ad Hoc Sensor Networks

Wireless Ad hoc Sensor Networks (WASNs) are self organizing, self-configuring and multi-hop wireless networks, in which each node communicates with other nodes directly or indirectly through intermediate nodes without any infrastructure. Besides these characteristics challenges like limited energy, dynamic topology, low bandwidth and security exists. The arrangement of nodes in WASN is called topology which changes dynamically with respect to time and mobility. Energy conservation is a major challenge because of the limited battery resource. In order to conserve energy in the network layer many techniques were used. These techniques can be classified mainly into two categories. The first technique is making small number of nodes awake to transfer bulk amount of data and to maintain the network connectivity and making the remaining nodes to be in sleep mode to conserve energy. This technique is effective for low traffic conditions. In the second technique, topology in the network is controlled by power control technique. This technique is effective for high data traffic. To conserve energy in an efficient manner, a Dynamic Traffic Energy Efficient Topology (DTEET) dynamically adjusts network topology for various network traffic conditions in WASN either in low traffic or high traffic is proposed. And the proposed protocol DTEET is stimulated by using AODV as routing protocol using network simulator ns2.34 and compared with AODV and DSR [1,2]. The simulation results revealed that the proposed scheme performs well in terms of energy, delay, delivery ratio and mobility

Simulation of Obstruction Avoidance Generously Mobility (OAGM) Model using Graph-theory Technique

An Obstruction Avoidance Generously Mobility (OAGM) model has been introduced for controlling ad-hoc sensor networks and thereby operating emerging fields like military and healthcare services. According to this model, the ability to send a message to a group of users simultaneously, based solely on their geographic location, is desirable by using Mission Critical Mobility model that assumes the obstacle shapes like rectangle or square in the simulation terrain. The OAGM model is developed by grasping the critical situations of military and healthcare services by incorporating the node movement model, hierarchical node organization, placement of obstacle that affect the movement of nodes and also signal propagation. Graph theory technique is used to find the shortest path of the node movement process. The varying number of parameter sets with DSR protocol is analyzed for MCM and OAGM mobility model. The results show OAGM performance is better than MCM.

Abnormal Human Being Vital Sign Detection Embedded on Smart Sensor with Collision Avoidance for Disaster Temporary Healthcare

In recent years, the production of mobile computing devices has motivated a revolutionary change in the computing world, which motivates the usage of a wireless ad-hoc and smart sensor network for monitoring the patient in disaster. Flow of signal from sensors to sink node may cause congestion in WSNs if a number of events sensing nodes attempt to send event information to the sink at the same time. Thus, this paper takes the advantages of smart sensors and proposes an energy-efficient and congestion avoidance vital signal detection framework to apply to the natural disaster results in a great number of injured people. The framework consists of several stages designed to improve the performance of wireless sensor networks. First, self-organized wireless ad-hoc and sensor network was simulated, in which all nodes try to organize themselves to organize a network. Nodes in the network reconfigure themselves repeatedly to respond to modifications in the number and location of nodes in order to prevent collisions in the receiver. In the second stage, we proposed a smart sensor processing system with the capability to extract the abnormal vital sign, to reduce the overhead in the aggregator and lower power consumption by sending only the abnormal vital sign. Furthermore, we propose to average polling rate to be suitable for both sender and receiver, in which the intermediate node can balance between the packet arrival rate and the packet service rate, thus avoiding congestion and enhancing the response time.

Vampire Attacks: Draining Life from Wireless Ad Hoc Sensor Networks

Ad hoc low-power wireless networks are an exciting research direction in sensing and pervasive computing. Prior security work in this area has focused primarily on denial of communication at the routing or medium access control levels. This paper explores resource depletion attacks at the routing protocol layer, which permanently disable networks by quickly draining nodes' battery power. These Vampire” attacks are not specific to any specific protocol, but rather rely on the properties of many popular classes of routing protocols. We find that all examined protocols are susceptible to Vampire attacks, which are devastating, difficult to detect, and are easy to carry out using as few as one malicious insider sending only protocol-compliant messages. In the worst case, a single Vampire can increase network-wide energy usage by a factor of O(N), where N in the number of network nodes. We discuss methods to mitigate these types of attacks, including a new proof-of-concept protocol that provably bounds the damage caused by Vampires during the packet forwarding phase.

VHF communication channel characterisations over complex wooded propagation paths with applications to ground wireless sensor networks

Results of measurement trials to estimate path loss and signal fading levels in very-high frequency band are presented for a node-to-node ad-hoc sensor network communication link with very low elevated antennas. Different typical landscapes were tested; from flat open areas to uneven woodland areas. Practical recommendations regarding utilisation of VHF band are formulated.

A Transferring Protocol using Local Information on Ad Hoc Sensor Network and Its Behaviors

To communicate over an ad hoc sensor network, many routing protocols usually collect information from the whole of the network. Thus, for transmitting a message, they consume an amount of power that is proportional to the size of the network. Now, we restrict the problem so that messages can be transferred only in a certain direction on a two-dimensional surface. If we solve this problem by employing a protocol using only local information, the protocol would consume an amount of power that is proportional to not the size of the network, but the length of the transmission path since only the nodes near the path would consume power. Inspired by the glider of the Game of Life cellular automaton, we propose a protocol designed to obtain information on the shape and the direction of movement of each group of nodes by using only local information. Our protocol has limited straightness for a random distribution of arrangements of nodes.

Vehicle Adhoc Sensor Network Framework to Provide Green Communication for Urban Operation Rescue

 Abstract—The use of wireless technology based on vehicle ad hoc network and wireless sensor network may give opportunity to the operational rescue team for emergency cases. Information transmitted using the vehicular and sensor technologies may improve the rescue communication. In this paper, a green communication framework is proposed to support the operation rescue together with green communication requirements. The proposed model is validated using two parameters which are average packet delivery ratio and level of congestion messages. The results are promising since we are using the 802.11Ext (extension for vehicle ad hoc protocol) to allow vehicle-to-vehicle communications.

Fast Consistent Chernoff Fusion of Gaussian Mixtures for Ad Hoc Sensor Networks

This correspondence examines the Chernoff rule for robust decentralized fusion of non-Gaussian pdfs in dynamic ad hoc sensor networks. Although theoretically appealing, the Chernoff rule is challenging to implement since it leads to fusion pdfs that cannot be obtained in closed-form and requires analytically intractable optimizations. Existing heuristic approximations to the Chernoff rule are generally inconsistent and do not accurately represent the fusion pdf. A fast new procedure based on Monte Carlo importance sampling, convex optimization and weighted expectation maximization is presented here to overcome these drawbacks and enable accurate online Chernoff fusion for ad hoc distributed sensor networks with Gaussian mixtures. Numerical experiments demonstrate the superiority of the proposed procedure.

EFFICIENT ENERGY SAVING AND DATA COLLECTION IN WIRELESS SENSOR NETWORKS

Energy efficiency operations are essential in increasing the lifetime of Wireless Sensor Networks. Clustering sensor nodes is an energy saving based interesting technique for achieving these goals. The main challenge in wireless sensor network is to optimize energy consumption when collecting data from sensor nodes. Efficiently collecting the data in wireless sensor networks plays a key role in power conservation. In this paper, a new energy-efficient approach for clustering nodes in adhoc sensor networks is proposed to collect data from sensor nodes and to reduce energy consumption using modified tabu search method, which enables with low communication cost. Dynamic Tabu search uses a local or neighborhood search procedure to iteratively move from a solution x to a solution x' in the neighborhood of x, until some stopping criterion has been satisfied. Communication between the distributed cluster heads is to be achieved by low cost. This approach is suitable to avoid the energy wastage during the transmission and to prolong the lifetime of sensor networks. The MNL (Maximising Network Lifetime) algorithm is being added to prolong the life time of the distributed network. NS-2 is used to perform the progress. The performance of distributed approach is to be compared with the centralized clustering approach using Dynamic modified tabu search.

A Forwarding Station Integrated with Optimal Cluster Number Selection in Wireless Sensor Networks

In wireless sensor networks, power consumption is the most important issue. That is wireless sensors are normally deployed into unattended places where power of sensors is hard to be charged. Indeed, the network lifetime of wireless sensor networks equipped with city power or deployed into attended place is much longer than those wireless sensors equipped with batteries. In general, wireless sensor nodes are connected together and become a network after deployed into certain places. With the certain range places that wireless senor nodes deployed into, finding the optimal clusters can increase the entire network lifetime. Also, adding the forwarding station extends the network lifetime. Therefore, this paper proposes the integration of both the forwarding station and optimal clusters in ad-hoc wireless sensor networks. Simulation results show that the entire network lifetime proposed is extended in this paper compared to both optimal cluster number selection and normal forwarding station.

Low-Complexity Distributed Total Least Squares Estimation in Ad Hoc Sensor Networks

Total least squares (TLS) estimation is a popular solution technique for overdetermined systems of linear equations with a noisy data matrix. In this paper, we revisit the distributed total least squares (D-TLS) algorithm, which operates in an ad hoc network, where each node has access to a subset of the linear equations. The D-TLS algorithm computes the TLS solution of the full system of equations in a fully distributed fashion (without fusion center). To reduce the large computational complexity due to an eigenvalue decomposition (EVD) at every node and in each iteration, we modify the D-TLS algorithm based on inverse power iterations (IPIs). In each step of the modified algorithm, a single IPI is performed, which significantly reduces the computational complexity. We show that this IPI-based D-TLS algorithm still converges to the network-wide TLS solution under certain assumptions, which are often satisfied in practice. We provide simulation results to demonstrate the convergence of the algorithm, even when some of these assumptions are not satisfied.

Detection of Malicious Sensor Node in Ad Hoc Sensor Networks based on Processor Utilization

paper proposes a strategy based on processor utilization value provided by each sensor node of the network for detecting their malicious activities by comparing the node's present processor utilization value with the old estimated value .If the difference between the two values is higher or less than the expected value then that particular node become suspicious. A knowledge based system can take decision to expel the malicious node from the network topology

Decentralized Detection in Ad hoc Sensor Networks With Low Data Rate Inter Sensor Communication

Decentralized binary detection problem in ad-hoc sensor networks where a link between two sensors is on with a certain probability is considered in this paper. We propose a consensus based detection scheme where sensors exchange their local decisions, update their own decisions based on the exchanges and finally reach a consensus about the state of nature. We analyze the error probability and convergence of this decision consensus scheme. We show that with our scheme, the detection performance in ad-hoc networks is asymptotically equivalent to that of a parallel sensor network where all the local decisions are processed by a central node (fusion center) in the sense that the error exponents are the same. The probability distribution of the consensus time is also studied. Simulation and numerical results are given to verify the theoretical results.

Analysis on Energy Optimized Data Collection in Tree Based Ad-Hoc Sensor Network

Fast and energy efficient data collection in an energy constraint ad-hoc sensor network is always a challenging issue. The network topology and interferences causes significant effects on data collection and hence on sensors' energy usage. Various approaches using single channel, multichannel and convergecasting had already been proposed. Here in this paper we have shown data collection performance using multi-frequency in channel assignment, and effect of network topology, for moderate size networks of about 50-100 nodes. For the study we have used some realistic simulation models under many-to-one communication paradigm called convergecast, a single frequency channel and TDMA technique to have minimum time slots for convergecasting.