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Energy is available all around us in various forms such as solar, thermal, piezoelectric, vibrational energies, etc. These forms of energy can be converted into electric energy that can power wireless sensors. Energy consumption of wireless sensor is a bottleneck in various applications that require long life time. This paper presents a detailed power consumption analysis of ZigBee based wireless...
In Wi-Fi networks, Device-to-Device (D2D) communications aim to improve the efficiency of the network by supporting direct communication between users in close proximity. However, in a congested Wi-Fi network, establishing D2D connections through a locally managed self-organising approach will intensify the congestion and reduce the scalability of the solution. Therefore, a centralised management...
Indoor tracking of smartphones adds context to smartphone applications, enabling a range of smarter behaviours. The predicted use cases are many and varied, and include navigation, planning, advertising and communication. Potentially, indoor tracking could become as ubiquitous as GPS — however, all of these possibilities depend on being able to produce a reasonably accurate, reliable system which...
In recent decades, due to limitation of radio spectrum and increasing users in wireless networks, spectral efficiency has been a considerable issue in literatures. In addition, energy consumption is rapidly increasing in wireless communications due to growing demand for wireless technologies especially cellular networks. Therefore, energy efficiency has become an important issue in such networks....
A distributed optimization algorithm is presented for resource allocation in wireless relay networks. This algorithm is particularly useful in multiple-source, multiple-relay wireless networks employing fractional cooperation, in which each relay contributes only a fraction of its resources to each source; in this case, the algorithm is used to find the optimal fractions. The advantage of this distributed...
The basic idea of the video data mining is based on the content of multimedia features and the semantics related to these properties, from large multimedia data sets and analysis of the underlying discovery, effective, valuable, and understandable patterns. In this paper, based on multi-encoding mode for real-time trans-coding of video streams we firstly research on the input data reuse pattern matching...
In order to make good use of the limited energy, ant colony optimization (ACO) was applied to inter-cluster routing mechanism. An uneven clustering routing algorithm for Wireless Sensor Networks (WSNs) based on ant colony optimization (ACO) was proposed. The algorithm utilized the dynamic adaptability and optimization capabilities of the ant colony to get the optimum route between the cluster head...
It has long been recognised that a wireless communication system can be more efficient if link-layer parameters such as modulation order, symbol rate and packet size, are (adaptively) optimised. A common optimising criterion is to maximise spectral efficiency (bits per second per Hertz (bps/Hertz)) subject to a very low bit-error constraint. But a packet-oriented criterion for link adaptation seems...
Radio frequency spectrum in wireless communication is a common resource shared by all collocated devices. Most spectrum management schemes rely on a centralized base station-receiver station relaying architecture. In contrast, infrastructure-less systems including wireless ad hoc networks require a scalable, distributed methodology. Moreover, the access has to be coordinated among the nodes in the...
The ultimate success of the Wireless Mesh Network paradigm (WMN) in large scale deployments depends on the ability to test it in real world scenarios. A typical application scenario which is worth to be investigated in such a context is peer-to-peer traffic management. The creation of large scale testbeds for evaluating wireless mesh technologies and protocols, and for testing their ability to support...
Transmission power control can significantly improve energy-efficiency of wireless sensor network communications. Power consumption models are typically based on dependence of channel attenuation on distance. However, in practice, information on distance is usually not available and the dependence of channel attenuation on distance is not sufficiently accurate. Therefore, we propose more accurate...
Recent advances in ultra-low-power circuits and energy harvesters are making self-powered body wireless autonomous transducer solutions (WATS) a reality. Power optimization at the system and application level is crucial in achieving ultra-low-power consumption for the entire system. This paper deals with innovative WATS modeling techniques, and illustrates their impact on the case of autonomous wireless...
In this paper, we study the selfish behavior in wireless sensor networks and apply a game theory method to address this problem in a CSMA/CA protocol. More specifically, we formulate the Media Access Control (MAC) layer activity in sensor networks as an optimization problem in terms of the random accessing problem. Then we propose a distributed algorithm for the system to reach the Nash Equilibrium...
The function and structure and the architecture of sensor network based on ZigBee/802.15.4 standard for forest monitoring are designed in this paper. According to the features of forest monitoring, the sensor nodes based on CC2520 and low power consumption chip MSP430F5437 and the coordinator Combing with ARM are designed which realize the energy control in physical layer. With the wireless sensor...
In future B3G/4G communication systems, the special application of femtocell in the enterprise offices and public places has broad prospect. However, as the femtocell operation under such multi-femtocell environment is significantly different from that of usual residential femtocells, the femtocell configuration and optimization might be much more complex. One key issue is to find how will the femtocell...
White space means spatially (or temporally) unused spectrum and this can be used on a unlicense basis. Since protecting primary users from harmful interference is the most important issue in unlicensed spectrum access on a secondary basis, regulatory authorities mandate the use of geolocation and DB (database) access capability as interference avoid scheme. The main role of this white space DB is...
Motivated by the need for fast computations demanded by wireless sensor networks, the new F-Lipschitz optimization theory is introduced for a novel class of optimization problems. These problems are defined by simple qualifying properties specified in terms of increasing objective function and contractive constraints. It is shown that feasible F-Lipschitz problems have always a unique optimal solution...
This paper discusses the design, simulation, development & testing of wideband, medium gain, lightweight, wide beamwidth pyramidal horn feed for terrestrial microwave line of sight communication in mobile & wireless applications. This antenna feed has been designed for X-band frequencies widely used in terrestrial microwave communication for mobile & wireless applications. Simulated &...
An antenna design framework using both low and high-technology is proposed. Sophisticated electromagnetic calculation technologies and manual optimization by engineers with little knowledge of antenna engineering have enabled the fabrication of practical antennas, which have unique structures different from those of conventional antennas. These unique antennas, which have equivalent electromagnetic...
Multiple Input Multiple Output (MIMO) delivers service simultaneously to more than one user which adds a new dimension, the spatial one, to be optimized in Cognitive Radio (CR). In this paper, statistical optimization techniques are carried out to assess the system performance where each type of users has different Quality of Service (QoS) demands. Closed form expressions are derived for different...
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