Li Xiuhua

A k-coverage scheduling scheme in wireless sensor network based on hard-core process in rayleigh fading channel

Sensing coverage is a fundamental design issue in wireless sensor networks (WSNs), while sensor scheduling ensures coverage degree to the monitored event and extends the network lifetime.In this paper, we address k-coverage scheduling problem in dense WSNs, we maintain a connected k-coverage energy efficiently through a novel Hard-Core based Coordinated Scheduling (HCCS), in which hardcore is a thinning process in stochastic geometry that inhibits more than one active sensor covering any area redundantly in a minimum distance. As compared with existing coordinated scheduling, HCCS allows coordination between sensors with little communication overhead. Moreover, due to the traditional sensing models in k-coverage analysis is unsuitable to describe the characteristic of transmit channel in dense WSNs, we propose a novel sensing model integrating Rayleigh Fading and Distribution of Active sensors (RFDA), and derive the coverage measure and k-coverage probability for the monitored event under RFDA. In addition, we analyze the influence factors, i.e. the transmit condition and monitoring degree to the k-coverage probability. Finally, through Monte Carlo simulations, it is shown that the k-coverage probability of HCCS outperforms that of its random scheduling counterpart.

Minimal coverage set detecting algorithm for barrier coverage in wireless sensor networks

Barrier coverage has attracted much attention in the past few years for its various applications, such as border surveillance and intrusion detection. In these applications, it is critical to achieve a strong barrier to ensure detecting any penetration of intruders in an energy-efficient manner so that the barrier can be covered with as few active sensors as possible. In this paper, we study the target detection problem through collaborative detecting under probabilistic sensing model, and propose a MCSD (minimal coverage set detecting) based on Graph theory, which seeks to achieve a strong barrier with minimal active sensors, prolonging the network lifetime. Finally, comprehensive simulations demonstrate that the proposed strategy improves network lifetime effectively.

Micro-level urban sensing through mobile data gathering with bus and SDMA technique

With the rapid development of urbanization, traditional urban sensing approaches cannot be sufficient to meet the growing demand of people. To achieve a highly reliable and stable urban sensing network, we propose a micro-level urban sensing schema. Participatory sensing and vehicle sensing are not suitable for this kind of network due to the active participation, the opportunistic or the deployment cost. In our schema, information is collected in a quite small scale by making full use of the existing sensing equipment and deploying a number of wireless distributed nodes. Buses equipped with data processor collect and process the sensing information. Since the reliability and stability of network depends on the energy consumption, the spatial-division multiple access (SDMA) technique is introduced to shorten transmission time in order to reduce sensor energy consumption. We apply linear decorrelator strategy of SDMA technique to reduce sensor energy consumption by equipping each bus station node and bus with dual antenna. Simulation results demonstrate that our approach outperforms the traditional approaches in reducing the energy consumption and then improving the reliability and stability to some extent.