Informatics Publishing Limited

Vivek Deshpande ¹, J. B. Helonde ², Vijay Wadhai ³

Affiliations
1 Department of Information Technology, MIT College of Engineering, Paud Road, Kothrud, Pune-38, IN
2 ITM College of Engineering, Nagpur, IN
3 MIT College of Engineering, Paud Road, Kothrud, Pune-38, IN

Abstract

Each node in Wireless Sensor Networks can communicate directly with other nodes in its radio communication range. If the destination node is not within the transmission range of the source node, the source node takes help of the intermediate nodes to communicate with the destination node by relaying the messages hop by hop. Hence the mutual cooperation and contribution of packet forwarding among the nodes in the network is needed. However, since the sensor nodes in this network are constrained with limited resources, such as CPU, battery, channel bandwidth and etc, some nodes in the network might not be willing to cooperate for the packet transmission, in order to save their resources. Each node has the goal to maximize its own benefits by enjoying network services and at the same time minimizing its contribution, so nodes may tend to be selfish. A selfish node does not intend to directly damage othernodes, but is unwilling to spend battery life, CPU cycles, or available network bandwidth to forward packets not of direct interest to it, even though it expects others to forward packets on its behalf. Consequently, cooperative behavior, such as unconditionally forwarding packets for others, cannot be taken for granted. The selfish behavior can significantly damage network performance.

Keywords

Selfish Node, Wireless Sensor Networks.

Full Text

     

J. B. Helonde ¹, Seema H. Rajput ², Vijay M. Wadhai ³, Amruta P. Chaudhary ²

Affiliations
1 Department of Electronic, ITMCOE, Nagpur, IN
2 Department of Electronic, SAE, Pune, IN
3 Department of Electronic, MIT, Pune, IN

Abstract

In wireless communication area, Cognitive radio is an emerging technology which draws attention for more efficient spectrum utilization systems. Cognitive radio is an intelligent mechanism of avoiding interference based on dynamic spectrum sharing. This paper deals with the design, implementation, simulation, and testing of the Smart Radio Channel Change Protocol (CCP). As nearly 80% of spectrum is underutilised, this technique is advantageous to reuse the frequency spectrum. The CCP enables a digital cognitive radio to detect the presence of legacy analog or digital radios, and to facilitate Channel-change procedures to use an alternate, vacant blocks of spectrum. This allows primary and secondary users to co-exist in the same band with minimal interference and improve quality of service (QoS). Here, this wireless network is evaluated using discrete event simulators like OMNeT++. The CCP is also advantageous to other systems’ frequency management schemes due to its simplicity of design and execution.

Keywords

Cognitive Radio, CR Security, Interference Avoidance, Dynamic Spectrum Sharing, OMNeT++.

Full Text

     

Shraddha K. Hatwar ¹, A. L. Wanare ², Dilip D. Shah ³, J. B. Helonde ⁴

Affiliations
1 G. H. Raisoni College of Engineering and Management, Wagholi, Pune, IN
2 Dr. D. Y. Patil School of Engineering, University of Pune, IN
3 G. H. Raisoni College of Engineering and Management, Wagholi, Pune, IN
4 ITM College of Engineering, Nagpur, IN

Abstract

In this Paper, a new formulation based on Least Square Regression (LSR) is discussed for image alignment. Contrary to the conventional approach, LSR technique takes an advantage in image restoration. Based on this formulation, three methods Wiener filter, Regularized filter and Blind Deconvolution are proposed and Peak Signal to Noise Ratio (PSNR) is discussed. Analysis is carried out by comparing the combination of single type of image and noise dealing PSNR for each image. We proposed automatic parameter estimation and selection of restoration methods for diversified field images.

Keywords

Blind Deconvolution, Least Square Regression, Regularized Filter, Wiener Filter.

Full Text