Rishi Pal Singh

Survey on Coverage Problems in Wireless Sensor Networks

The paper describes the concept of coverage problem in the wireless sensor networks (WSNs). The issue of quality of service is more closely related to the coverage problem in WSNs. The motive behind the coverage problem is to have the supervision of at least one node at every point of targeted region. Efficient coverage can be defined as the network lifetime by describing the features like sensing ability and energy consumption by sensing nodes. The covering strategies based on Computational Geometry are discussed and various other strategies have been elaborated.

A Localization Scheme for Underwater Sensor Networks Without Time Synchronization

AbstractThe underwater sensor networks (UWSNs) exhibit different characteristics from terrestrial WSNs. To make the sensed data meaningful, one of basic task is the localization of sensor nodes. In UWSNs, this is not feasible to use global positioning system due to its issue of propagation. This senses localization as a fundamental as well as sound issue in the UWSNs. In spite of continuous and sincere research effort, the time synchronization between the sensor nodes for their localization is also a tough job. To address these issues, a localization scheme free from the concept of time synchronization for large scale 3D-UWSNs based on dive and rise mobile beacons floating over the sea surface has been proposed in the given paper. The analytical analysis of the proposed scheme is also presented in the paper. In the simulation section, the performance of the proposed scheme is evaluated in terms of coverage and the number of localized nodes. A discussion based on various obtained results is also given in the paper.

Performance modeling of slotted MACA-BI MAC protocol for mobile ad hoc networks

Medium-access-control (MAC) protocol for wireless networks proposed are based on collision avoidance using handshake between sender and receiver. The earlier existing protocols are sender initiated. In this paper, an attempt has been made to propose the model, which uses collision avoidance using receiver initiated handshake. In this model, the channel is divided into equal and static size slots. The proposed model uses carrier sensing and frequency hoping spread spectrum.

Throughput Analysis of IEEE 802.11 DCF with Modified Binary Exponential Backoff in Mobile Ad Hoc Networks

In the design of wireless networks, the medium access protocols have a very large impact on the performance of the network. The IEEE 802.11 is widely accepted technology for the Wireless LANs and is used by wireless networks. This paper presents an analysis of the performance of Distributed Coordination Function DCF for IEEE 802.11 under modified Binary Exponential Backoff BEB Algorithm using Frequency Hoping Spread Spectrum FHSS. In the modified algorithm, the size of Contention Window CW has been changed with the factor of for the first four collisions and the size becomes double thereafter in each subsequent collision. This paper also covers the effects of various parameters in modified BEB Algorithm.

Home Automation Using Internet of Things

Internet of Things is the internetworking of devices such as heart monitoring, automobiles with built-in sensors, environmental monitoring, home automation and lightning that enable these devices to gather, communicate, share, receive, and transfer data over a network. The Internet of Things is about making the surrounding environment smart including the buildings used for living beings like homes and hospitals. In this paper, various sensors are deployed in home such as motion sensors, luminance sensors and temperature sensors, is discussed. Algorithm to save the energy of lights and air conditioners of the entire home is also implemented in this paper. Energy consumption before and after implementation of system model has been calculated which showed that a total of 20.78% energy has been saved.

Coarse-Grain Localization in Underwater Acoustic Wireless Sensor Networks

Underwater Acoustic Wireless Sensor Networks (UASNs) is the way to connect underwater environment with the rest of the world. The existence of the huge number of applications which need to monitor the underwater environment, it is gaining popularity. The collected data from these networks are meaningless without the physical location of the sensor nodes. Localization schemes relate the data with its spatial information. In this paper, we have developed a localization scheme for Underwater Sensor Networks which gives a Coarse-Grain location information of the sensor nodes. The simulation results show that with a less energy consumption more than \(90\%\) of underwater sensor nodes can be localized by the proposed scheme.

Coverage Hole Detection and Healing to Enhance Coverage and Connectivity in 3D Spaces for WSNs: A Mathematical Analysis

The coverage and connectivity are the two imperative performance metrics for the growth of wireless sensor networks (WSNs) with sprouting technologies. In order to maintain these metrics, the issue of finding and healing of coverage hole is closely related to these two facts and plays a vital role in the performance improvement of the network. Many works in the past explored for 2D-WSNs, but now the time has come to investigate this matter for 3D-WSNs to reach the new heights of research and technology. In this paper, different scenarios with respect to the deployment of sensor nodes or network topology with the presence of different shaped coverage holes are discussed. Not only this, to heal these perceived holes introduction of sensor nodes having sensing radius different from initial deployed sensors has been suggested which in turn outlines the development of heterogeneous sensor networks, a keen issue with respect to technology development. This deployment of sensors to constitute heterogeneous sensor networks also influences the overall network cost in terms of cost reduction with an optimum coverage level. A mathematical analysis to give a relationship between the radii of former and later deployed sensor nodes is presented in the form of theorem. At the end, the results and discussion in order to achieve a specified level of coverage with respect to different packing patterns based on the mathematical analysis are provided. Also, some future directions to guide the researchers are discussed in this paper.

Secure Deployment with Optimal Connectivity in Wireless Sensor Networks

In the hostile areas, deployment of the sensor nodes in wireless sensor networks is one of the basic issue to be addressed. The node deployment method has great impact on the performance metrics like connectivity, security and resilience. In this paper, a technique based on strong keying mechanism is proposed which will enhance the security of a non-homogeneous network using the random deployment of the nodes. For this, the q-composite key pre-distribution technique is presented with new flavor that will enhance the network size as well as the security level in comparison to the existing techniques. The technique ensures the k-connectivity among the nodes with a redundant method to provide backup for failed nodes. In the simulation section, the performance of the proposed scheme is evaluated using NS-2 based upon the real model MICAz. A discussion based on various obtained results is also given in the paper.

Modelling of IEEE 802.11 DCF in the presence of hidden nodes

Today, the most commonly used technology for wireless networks is IEEE 802.11. The performance of the Medium Access Control MAC layer, which consists of Distributed Coordination Function DCF and Point Coordination Function PCF, has been examined over a long time period. The DCF is the random access scheme that uses CSMA/CA in IEEE 802.11 MAC layer protocol. There are various issues related to the performance evaluation of IEEE 802.11 DCF and one of the important issues is the problem of hidden terminals which exists in practice in any wireless network. In this paper, a two-dimensional analytical model is proposed for the analysis of IEEE 802.11 DCF in the presence of hidden terminals for both basic access and RTS/CTS modes by making use of the Markov chain.