The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Dynamic behavior is an essential part of wireless networking, due mobility, environmental changes or failures. We analyze a natural exponential backoff procedure to manage contention in a fading channel, in the presence of both node churn and link changes. We show that it attains a fast convergence, stabilizing contention from any state in logarithmic time. We use it to obtain optimal algorithm for...
Reliability, interoperability and efficiency are fundamental in Wireless Sensor Network deployment. Herein we look at how transmission power control may be used to reduce interference, which is particularly problematic in high-density conditions. We adopt a distributed approach where every node has the ability to learn which transmission power is most appropriate, given the network conditions and...
With the emergence of energy harvesting technologies, the energy harvesting wireless sensor network (EH-WSN) provides near-perpetual energy supply for sensor nodes. The routing techniques based on energy-efficient are not suitable for EH-WSN. In this paper, we focus on the routing problem for EH-WSN. We first describe the factors of affecting routing performance in EH-WSN and present three related...
Rapid development in wireless sensor device manufacture technologies has made it possible to conglutinate and implant the medical sensors on human body. The improvement of these technologies can be applied to wireless body area network (WBAN) on medical applications. A uniform standard in the field of WBAN, IEEE 802.15.6 has been released recently by IEEE 802.15 TG 6 group, indicating that WBAN will...
Cognitive Radio Networks enable a higher number of users to access the spectrum of frequency simultaneously. This access is possible due to the implementation of dynamic spectrum allocation algorithms. In this context, one of the main algorithms found in the literature is the reinforcement learning based approach called Q-Learning. Although been widely applied, this algorithm does not take into account...
Abstract-This paper deals with an efficient and energy-saving channel assignment scheme which is applicable to the Wireless Sensor Network (WSN). In actual application, there exist inevitably serious interference and conflict between nodes due to their large quantity and density in WSNs. Usually, the sensor nodes in WSNs rarely move and the their energy is also limited. So in this paper, we divide...
Wireless sensor networks (WSNs) consist of a large number of wireless sensor nodes that organize themselves into multi-hop radio networks. With different link quality, different distance to the sink, etc., nodes in a network are not treated equally, especially in the network with high traffic. In this paper, we propose a fairness spatial reuse time division multiple access (TDMA) scheduling algorithm...
Energy efficiency is an important consideration in a battery powered wireless sensor network (WSN). We propose an energy efficient Distributed Power Management algorithm with Directional Antenna (DDISPOW) that adaptively manages nodes' power in a dynamic wireless network to preserve network connectivity and reduce interference cooperatively. DDISPOW, with adequate transmit power, is capable of providing...
Spectrum management in cognitive radio is one of the most challenging issues and has attracted much research attentions in recent years. However most of the existing works consider either online demands or scheduled demands, which may not fully capture the flexible nature of the demands in certain circumstances, such as the communication demands for a synchronized sensing data transmission in wireless...
A critical issue in wireless sensor networks isrepresented by the limited availability of energy withinsensor nodes. An effective approach for energy conservationis scheduling sleep intervals for extraneous nodes, while theremaining nodes stay active to provide continuous service.Most previous solutions assumed a perfect radio conditionwith a static, circular coverage. However, in real situations,radio...
Interference is an issue of outstanding importance for efficient communication in ad-hoc wireless networks. Interference arises due to overlapping transmission power levels of nodes and causes message collisions that require energy-consuming retransmissions. In this work we study algorithms for interference control in ad-hoc wireless networks in the Euclidean space that aim at constructing low-interference...
An important problem in multi-radio multi-channel wireless mesh networks is how to perform efficient network-wide broadcasting. While route discovery or energy efficiency is the major concern for broadcasting in mobile ad-hoc networks or sensor networks, in WMNs, more attention should be paid to the high-throughput schemes. In this paper, we propose an interference-aware broadcast routing and channel...
An efficient channel selection scheme is necessary for any single or multiple radios mesh routers in order to exploit multiple channel operations in wireless mesh networks. Such a scheme, among other things should have fast switching and process coordination modules incorporated to its design framework so as to minimise interference and maximise throughput. This paper presents an enhancement to a...
As ubiquitous networking emerges, ZigBee devices among various communication devices in the PAN have attracted considerable attention in sensor networks. However, ZigBee devices may significantly experience severe degradation in the presence of WLAN. We propose dynamic clustering schemes of ZigBee networks in order to avoid the WLAN interference. Simulation results show that our proposed scheme is...
Task-centric wireless sensor network environments are often characterized by the simultaneous operation of multiple tasks. Individual tasks compete for constrained resources and thus need resource mediation algorithms at two levels. First, different sensors must be allocated to different tasks based on the combination of sensor attributes and task requirements. Subsequently, sensor data rates on various...
Thanks to recent advances in wireless technology, a broad range of standards are currently emerging. Interoperability and coexistence between these heterogeneous networks are becoming key issues, which require new adaptation strategies to avoid harmful interference. In this paper, we focus on the coexistence of 802.11 WLANs and 802.15.4 sensor networks in the ISM band. These networks have very different...
In this paper, we analyze the performance of the GADIA (Greedy Asynchronous Distributed Interference Avoidance) algorithm ([1], [2]) given the spectral sensing time of the various active agents. Under the assumption that the sensing time is small compared to the update intervals, it is shown that the algorithm converges to an equilibrium point. We also derive the steady state variance of the error...
Network coding is known to improve throughput by mixing information from different flows and conveying more information in each transmission. Recently some proposals have demonstrated the benefits of applying network coding to wireless networks with broadcast transmissions. It is expected that the opportunities for coding and the corresponding gains depend on the bit-rate chosen for determining routes...
For target tracking in Interference Environments of cognitive radar problem, Extended Karman, Particle filter algorithms etc. are generally used to be regarded as usual solutions to state estimation. Many techniques have been developed to improve performance of target tracking. In this paper, we set the structure and key features of target's tracking design for cognitive radar, and newly propose cognitive...
Wireless sensor networks consist of a large number sensors spread across a given geographical area. Each sensor has its own communication capability as well as certain level of intelligence for signal processing and networking. As the sensor nodes are densely populated, communication range requirement for these nodes is smaller. After signal detection, a number of sensor nodes communicate over the...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.