Optimization of Power Consumption in 4G LTE Networks Using a Novel Barebones Self-adaptive Differential Evolution Algorithm

The power consumption of wireless access networks is an important issue. In this paper, the power consumption of Long Term Evolution (LTE) base stations is optimized. We consider the city of Ghent, Belgium with 75 possible LTE base station locations. We optimize the network towards two objectives: the coverage maximization and the power consumption minimization. We propose a new Barebones Self-adaptive Differential Evolution. The results of the proposed method indicate the advantages and applicability of our approach.     

A test lab for the performance analysis of TCP over ethernet LAN on windows operating system

A test laboratory for the performance analysis of the Transmission Control Protocol (TCP) and the teaching of its basic concepts is proposed. The laboratory environment is a small Ethernet local area network (LAN) with PCs running different versions of the Windows operating system (95/98/NT/2000). To support the Internet Protocol Version 6 (IPv6) for Windows and to improve flexibility, the Netperf TCP software tool has been modified. Based on the modified Netperf and a protocol analyzer, students perform traffic measurements on a real network. Various aspects of the Microsoft TCP implementation for Windows are discovered and clearly explained. The IPv6 for Windows 2000 is also examined, and comparisons with IPv4 are made.     

A Survey of IoT Key Enabling and Future Technologies: 5G,Mobile IoT,Sematic Web and Applications

The Internet of Things (IoT) is the communications paradigm that can provide the potential of ultimate communication. The IoT paradigm describes communication not only human to human (H2H) but also machine to machine (M2M) without the need of human interference. In this paper, we examine, review and present the current IoT technologies starting from the physical layer to the application and data layer. Additionally, we focus on future IoT key enabling technologies like the new fifth generation (5G) networks and Semantic Web. Finally, we present main IoT application domains like smart cities, transportation, logistics, and healthcare.     

On the base stations antenna system design for mobile communications

The design of a base station antenna for mobile communications is presented. The orthogonal method (OM) is applied under constraints on nulls of the radiation pattern. In the synthesis process the mutual coupling between the elements of the antenna array could be taken into account. Beam tilting and direction of arrival are also considered. The whole design is completed by implementing a special architecture of the antenna. Finally, some examples show the applicability of our technique.     

Design of optimum gain pyramidal horn using self‐adaptive differential evolution algorithms

In this work, we apply classical and new self‐adaptive differential evolution (DE) algorithms to the design of optimum gain pyramidal horns. The application of DE algorithms to pyramidal horn design allows the accurate calculation of their physical dimensions in a short amount of time. Moreover, self‐adaptive DE does not require the prespecified choice of control parameters reducing significantly the users' effort. Representative examples demonstrate the applicability of our proposal. Our study shows that self‐adaptive DE algorithms outperform or produce similar results with other methods in the literature in terms of solution accuracy and convergence speed. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.     

Model-driven eGovernment interoperability: A review of the state of the art

This paper reviews the state of the art in the area of enhancing eGovernment interoperability by using common models and/or ontologies. This area has currently become a very active research field. We identify and present a significant number (> 40) of relevant efforts. These initiatives are grouped into categories based on the owner, scope and modelling perspective of each project. We then focus on the cases that build generic and universal eGovernment representations and models. We analyse, evaluate and rate them using an additional set of criteria. We end up with conclusions and possible directions for the exploitation and usage of these models.     

Direct solution and Monte Carlo simulation of the inverse problem in two-layered half-space

 A direct method is developed for determining the dielectric properties and thickness of lossy two-layered media. The technique is based on the study of the frequency response of the complex reflection coefficient. The frequency span must contain at least two adjacent extreme values of the real part of the input impedance. Monte Carlo simulations were produced in order to test the accuracy of the method. Applications in hydrology, engineering and environmental geology are discussed. Received: 14 May 2001/Accepted: 5 June 2001     

On the quantized excitation and the geometry synthesis of a lineararray by the orthogonal method

A method for the geometry synthesis of a linear array is presented. We start from an initial array with quantized amplitudes. After this, we perturb the element positions by combining an iterative technique with the orthogonal method. The final position of the elements is found from the last iteration where the desired approximation of the pattern is obtained. Arrays with more constraints on the pattern need more quantized amplitudes. Several examples for different cases show the applicability of our method     

Orthogonal Advanced Methods for Antennas: the ORAMA computer tool

A computer tool (ORAMA) for the synthesis of linear antenna arrays is presented. The orthogonal method (OM) and the orthogonal perturbation (OP) method are used. The orthogonal method derives the excitation of the elements of the array, while the orthogonal perturbation method quantizes the excitation and determines the position of the elements. The user has the options to select the array geometry, the case study for a specific desired pattern, the method to be used, and the element type. Several design cases with various constraints are presented. ORAMA (a demo of the software is available at http://rcl.physics.auth.gr) has been designed as a Windows MDI application for the academic classroom, as well as for professional antenna engineers. A set of examples for different array patterns shows the usefulness of the tool.     

On the design of switched-beam wideband base stations

A switch beam base-station antenna is presented. The antenna is an improvement on the Butler matrix. The input ports of the antenna are excited with equal or unequal amplitudes. The feed network is analyzed and presented in a simple manner. The antenna comprises the main part of a base station, and is useful for broadband communications. The architecture of the base station is described, and the services that can be provided are given. Finally, comments are made about the tradeoffs and benefits of the antenna in comparison to the classical Butler-matrix switched-beam and adaptive arrays.