International Journal of Sensors Wireless Communications and Control - Volume 4, Issue 1, 2014

During the last decade, there has been an efficient use of wireless sensor networks (WSNs) in different fields such as environmental surveillance, military, disaster management, medical, etc. In these applications, large number of sensor nodes are deployed, which work in harsh environment. The main objective of the wireless sensor nodes is to observe the event and inform the same to other node or to sink. There are some applications in the wireless sensor networks which require exact time of the event occurrence. Such applications require that nodes of the WSN should be synchronized with global clock. In this paper, we study the impact of time synchronization and analyze various time synchronization protocols highlighting their features, objectives and perform qualitative and quantitative analysis.

Developing an embedded, automated system is a challenging task because it requires a fully managed system implemented with the involvement of several electronic components, external printed circuit boards (PCBs) and miscellaneous advanced devices to be attached and used in an organized way. Here, the focus is on the development of such a system to regulate the electronic devices implanted in a building (house, office etc.) from desktop and mobile application. Meeting the technological goals of this research and development, this manuscript introduces a new application, i.e. Smart House, a combination of the both hardware and software. The proposed system is capable of controlling several electronic appliances, scheduling the operations, recording the operational activities and implementing security system to track the interruptions. This manuscript briefly explores the implemented application, including its features, usage, pitfalls and implemented hardware.

In this paper a host microstrip line loaded with complementary split ring resonators is presented. The transmission line is modified in order to increase the electric coupling with the resonators and therefore obtain a high pass behavior. The analysis is performed through full-wave electromagnetic simulations, equivalent circuit responses and measurement of a fabricated prototype. The results obtained show a high pass response conversely to conventional microstrip loaded transmission lines where a narrow band pass is obtained. The final line obtained has compact size. It is due to the electrically small dimensions of the resonators used. As a consequence, the transmission lines proposed in this work can be employed in applications with severe size constrains and wide band pass responses.

This paper proposes a new method for enhancing the accuracy and availability of positioning in indoor environment based on fusion of the positioning results obtained from two sensing technologies, Inertial Navigation System (INS) and Wireless Sensor Network (WSN) (in this case Bluetooth- based positioning system). The performance of each individual sensing technology has been optimised first using new positioning methods before performing the fusion of results. The fusion is achieved by the utilisation of two fusion filters, particle filter and Extended Kalman filter, and is thoroughly tested using a portable data acquisition unit which is specially designed for that purpose. Detailed analysis and comparison of the performance between particle filter and Extended Kalman filter has been performed. Results show that the proposed fusion method reduces the errors compared to single sensing technology and the mean distance error of the final fused system is maintained below 1 metre using either of the two filters.

The present paper proposes a novel Energy Efficient Collision Avoidance Method (EECAM) for Collaborative Event Driven Energy Efficient Protocol (CEDEEP). EECAM makes possible higher energy savings by introducing nodes prioritization according to distinctive properties of CEDEEP protocol and event driven Wireless Sensor Network (WSN) applications. In this research the higher energy conservation caused by deployment of EECAM within CEDEEP have been investigated. A stochastic model of the one hop network is developed and the effectiveness of EECAM is illustrated considering Sift protocol in event driven WSN applications. The results of the evaluations confirmed significant improvements in energy consumption of CEDEEP when EECAM is used. Therefore, this research gives strong evidences that use of EECAM instead of Sift at media access control (MAC) layer results into higher energy efficiency of CEDEEP in event driven applications. Furthermore, this higher energy efficiency of CEDEEP with EECAM ensures considerably longer lifetime of WSNs in event driven application scenarios.