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In this paper, a novel method to efficiently calculate the power transfer efficiency of a wireless power transfer system in the radiative near-field is proposed. The technique allows repositioning of the antennas without large additional cost. It relies on a single simulation (or measurement) of the radiation pattern of the antennas used. Thanks to its high computational efficiency, it can be used in multi-transmitter and multi-receiver scenarios when there is no coupling between devices via the reactive near-field. Our method is applied to the latter to demonstrate its accuracy and computational efficiency. [ABSTRACT FROM AUTHOR]

In the last times, the improvement of the digital television has opened to the novel design of devices for the reception of the sign. The present work is focused in the obtaining of an antenna in printed technology in the band of 470-890 MHz for the television services. In the same one the main characteristics of the microstrip antennas are analyzed and of the logarithmic periodic (LPDA) as they are the entrance impedance, diverse configurations, feeding ways; analyzing the advantages and disadvantages that can bring the coalition of both for the design. Also intends a group of considerations for the design of the antenna, taking as main objectives to achieve a smaller size of the device, a low profile and a good yield for the wanted band of frequencies. The simulations of the design in the software Ansoft HFSS v12 is analyzed, corroborating the execution of the initial goals. [ABSTRACT FROM AUTHOR]

This letter presents an antenna design method for an orthogonally-polarized dual antenna for use in mobile stations (MSs) and includes a verification method for improving the link-level throughput performance of an MS that uses a proposed multiple-input multiple-output antenna. The link-level throughput performance of an MS is strongly related to the correlation between antenna branches, which is determined by the cross polarization discrimination of the second branch antenna, both numerically and experimentally. [ABSTRACT FROM AUTHOR]

A novel frequency-switchable antenna that uses PIN diodes and a composite right- and left-handed transmission line (CRLH TL) is proposed. The CRLH TL provides multi-order resonance, including a zeroth-order resonance (ZOR), and its shunt stub determines the ZOR frequency. Thus, the resonant frequency is arbitrarily chosen by lumped chip inductors on the shunt stub. Two prototypes are designed using different chip inductors while maintaining the antenna geometries. Antenna #1 can switch the resonant frequency from 1.8 GHz to 2.3 GHz. Antenna #2 can switch its resonance from 0.9 GHz to 2.3 GHz. [ABSTRACT FROM AUTHOR]

Approximate minimum symbol error probability transceiver design of single user MIMO systems under the practical per-antenna power constraint is considered. The upper bound of a lower bound on the minimum distance between the symbol hypotheses is established. Necessary conditions and structures of the transmit covariance matrix for reaching the upper bound are discussed. Three numerical approaches (rank zero, rank one, and permutation) for obtaining the optimum precoder are proposed. When the upper bound is reached, the resulting design is optimum. When the upper bound is not reached, a numerical fix is used. The approach is very simple and can be of practical use. [ABSTRACT FROM AUTHOR]

In this paper, we use for the first time the ray-tracing method combined with the HFSS software to analyze lens antennas. HFSS is a very popular commercial tool that can provide very accurate results for the simulation of antennas. However, because of limitations on computational resources, it is hard to apply to solving large electromagnetic problems. In this paper, HFSS is used to simulate the fields of the feed part of a lens antenna. The ray tracing method is adopted for the lens part. This treatment makes the combined method feasible for solving large lens antennas. In using the ray-tracing method, cubicspline interpolation is exploited to fit the face of the lens and to solve for the derivatives at each point on the curved surface. Newton's method is applied to find the intercept between the ray and the curved surface. The numerical method proposed in this paper is very suitable for the analysis of dielectric lens antennas with arbitrary feeds and lens shapes. The validity of the idea is demonstrated by comparing the simulation results of this new method with those from using CST (Computer Simulation Technology) software. Very good agreement is achieved. [ABSTRACT FROM AUTHOR]

Introduction of the Daisy multimedia book format, which integrates text, sound, images and video in a synchronized sequence. Daisy presents a high usability for digital reading thanks to its advanced navigation through text or audio. The article also describes DTBook, the text component of Daisy, which is a highly structured xml format ideal to create alternate format editions. The article sets out the differences between Daisy and other audiobooks and presents the most common Daisy players and Daisy market adoption. The format has good potential for becoming a flagship format in ebook publishing if costs of playing devices decrease and a solution is found for digital rights management. [ABSTRACT FROM AUTHOR]

Optimum combining (OC) is a powerful means for combatting co-channel interference. Its performance, however, is difficult to analyze. The prevailing methodology in current use is to neglect the influence of additive white Gaussian noise (AWGN). Inclusion of AWGN into the analysis usually leads to mathematical intractability, except for some extreme cases. In this letter, we formulate the problem in the framework of hypergeometric functions, so that their good properties can be exploited to enable the analysis to account for the influence of AWGN and co-channel interference simultaneously. We obtain closed-form solutions to the characteristic function (CHF) of the signal-to-interference-plus-noise ratio at the OC output for three important operational scenarios in Rayleigh fading, although the general solution still needs further effort to simplify. The assumptions made here are that both signal and interferers suffer from Rayleigh fading, and the number of interferers is not less than the number of antennas. The use of resulting CHF formulas is illustrated through their application to the bit-error and outage performance evaluation of OC. [ABSTRACT FROM AUTHOR]

The use of smart antennas in wireless ad hoc networks has garnered attention over the last few years. Given the unique capabilities of smart antennas, and how they can improve performance in a typically constrained ad hoc network environment, the attention is with merit. However, not much light has been shed on wireless ad hoc networks that have nodes with varying antenna capabilities. While homogeneous ad hoc networks with all nodes having the same antenna capabilities will have certain applications, we argue that ad hoc networks with nodes having heterogeneous antenna capabilities are more likely to be the norm due to a variety of motivating factors. In this context, we answer two fundamental questions in this paper: (i) what is the theoretical capacity of an ad hoc network when its nodes have varying antenna capabilities? We consider nodes equipped with only omnidirectional antennas to those that are equipped with more sophisticated adaptive-array and MIMO capable antennas. Perhaps more interestingly, we provide insights into what percentage of nodes in an ad hoc network have to be ‘smart’ to get a certain overall network capacity. (ii) What medium access control (MAC) and routing protocols should nodes use in such a heterogeneous network? We present MAC and routing protocols for ad hoc networks with heterogeneous antenna capabilities that allow nodes to interact with each other effectively despite their heterogeneity, and in the process deliver considerably improved performance over simplistic strategies. We substantiate our theoretical results, and evaluate the proposed protocols using ns2-based network simulations. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents the design of space-time turbo trellis coded modulation (ST turbo TCM) for improving the bandwidth efficiency and the reliability of future wireless data networks. We present new recursive space-time trellis coded modulation (STTC) which outperform feedforward STTC proposed by Tarokh et al. (1998) and Baro et al. (2000) on slow and fast fading channels. A substantial improvement in performance can be obtained by constructing ST turbo TCM which consists of concatenated recursive STTC, decoded by iterative decoding algorithm. The proposed recursive STTC are used as constituent codes in this scheme. They have been designed to satisfy the design criteria for STTC on slow and fast fading channels, derived for systems with the product of transmit and receive antennas larger than 3. The proposed ST turbo TCM significantly outperforms the best known STTC on both slow and fast fading channels. The capacity of this scheme on fast fading channels is less than 3 dB away from the theoretical capacity bound for multi-input multi-output (MIMO) channels. [ABSTRACT FROM AUTHOR]

An optimisation framework is proposed to properly focus on near-field locations using antenna arrays. This method is able to overcome the traditional problems of near-field focused antennas, obtaining some appropriate weights to be applied at the elements of the array so that the secondary lobes are reduced and the maximum level of the field is placed at the desired point. An illustrative example using simulated antennas is addressed to evaluate the capabilities of this framework. [ABSTRACT FROM AUTHOR]

This article discusses the development of the Rosetta programming language for use in the system-level design of electronics. The elaboration of the semantics of this language by the Institute of Electrical and Electronic Engineers Inc. Computer Society (IEEE) P1699 Rosetta Working Group is described. The challenges of incorporating information on performance constraints and heterogeneous domain characteristics in the development of so-called system-on-chips (SoCs) are described. The characteristics of Rosetta, which is a heterogeneous, declarative, and formal language for engineering SoCs is noted. The development of the facet and domain based definition systems for this language is explored.

A subject index for the November 2013 issue of the "IEEE Transactions on Consumer Electronics" is presented.

The article offers brief information on the FEKO antenna design and placement solution from FEKO.

Provides an overview of the topics to be featured in the upcoming issue of the "International Journal of Microwave and Millimeter-Wave Computer-Aided Engineering. Stripline-fed cylindrical slot antennas; SPICE model for angled multipin connectors; CAD of waveguide components and antennas; Network synthesis methods in microwave design.