Peter S. Excell

Wideband Printed MIMO/Diversity Monopole Antenna for WiFi/WiMAX Applications

A novel printed diversity monopole antenna is presented for WiFi/WiMAX applications. The antenna comprises two crescent shaped radiators placed symmetrically with respect to a defected ground plane and a neutralization lines is connected between them to achieve good impedance matching and low mutual coupling. Theoretical and experimental characteristics are illustrated for this antenna, which achieves an impedance bandwidth of 54.5% (over 2.4-4.2 GHz), with a reflection coefficient <;-10 dB and mutual coupling <;-17 dB. An acceptable agreement is obtained for the computed and measured gain, radiation patterns, envelope correlation coefficient, and channel capacity loss. These characteristics demonstrate that the proposed antenna is an attractive candidate for multiple-input multiple-output portable or mobile devices.

A Low-Profile Ultra-Wideband Modified Planar Inverted-F Antenna

A miniaturized modified planar inverted-F antenna (PIFA) is presented and experimentally studied. This antenna consists of a planar rectangular monopole top-loaded with a rectangular patch attached to two rectangular plates, one shorted to the ground and the other suspended, both placed at the optimum distance on each side of the planar monopole. The fabricated antenna prototype had a measured impedance bandwidth of 125%, covering 3 to 13 GHz for reflection coefficient better than -10 dB. The radiator size was 20×10×7.5 mm3, making it electrically small over most of the band and suitable for incorporation in mobile devices. The radiation patterns and gains of this antenna have been cross-validated numerically and experimentally and confirm that this antenna has adequate characteristics for short range ultra-wideband wireless applications.

A Crescent-Shaped Multiband Planar Monopole Antenna for Mobile Wireless Applications

A planar multiband monopole antenna is presented for mobile wireless applications. The antenna is constructed from a crescent-shaped radiator patch, microstrip feed line, and defected ground structure (DGS). Theoretical and experimental characteristics are presented for this antenna, which achieves an impedance bandwidth of 58.3% (over 1.7-3.1 GHz), at a reflection coefficient |S11| < -10 dB and has an average gain of 1.75 dBi.

A Planar Inverted-F-L Antenna (PIFLA) With a Rectangular Feeding Plate for Lower-Band UWB Applications

A planar inverted-F-L antenna (PIFLA) with a broadband rectangular feeding structure is proposed for lower-band ultrawideband (UWB) applications. This antenna is constructed from a driven F-shaped element and a parasitic L-shaped element. Both patches are inverted and aligned face to face over a finite ground plane; the optimized dimensions of this antenna are 30 × 15 × 4 mm3. The realized antenna achieves a gain between 2.5 and 4.7 dBi over a 66.6% impedance bandwidth (on the interval 2.85.6 GHz) for |S11| ¿ -10 dB. The radiation patterns, antenna efficiency, and antenna group delay are also measured and discussed.

Designing Augmented Reality Games for Mobile Learning Using an Instructional-Motivational Paradigm

In this paper, several Augmented Reality(AR) games used in mobile learning have been evaluated. It is concluded that AR adds a real sense of learning to mobile games by providing models of real world settings for learners. The learning objectives must be integrated into the game rules, story and different levels. The game model must be close to the real world; each team member must have distinct roles; resources must be constrained and appropriate feedback and challenges must be used throughout the game system. By using this emerging paradigm of instruction, educators can effectively incorporate these games into their curricula.

A review on Internet of Things (IoT), Internet of Everything (IoE) and Internet of Nano Things (IoNT)

The current prominence and future promises of the Internet of Things (IoT), Internet of Everything (IoE) and Internet of Nano Things (IoNT) are extensively reviewed and a summary survey report is presented. The analysis clearly distinguishes between IoT and IoE which are wrongly considered to be the same by many people. Upon examining the current advancement in the fields of IoT, IoE and IoNT, the paper presents scenarios for the possible future expansion of their applications.

The Design of a Resistively Loaded Bowtie Antenna for Applications in Breast Cancer Detection Systems

A resistively loaded bowtie antenna, intended for applications in breast cancer detection, is adaptively modified through modelling and genetic optimization. The required wideband operating characteristic is achieved through manipulation of the resistive loading of the antenna structure, the number of wires, and their angular separation within the equivalent wire assembly. The results show an acceptable impedance bandwidth of 100.75%, with a challenge VSWR <; 2, over the interval from 3.3 GHz to 10.0 GHz. Feasibility studies were made on the antenna sensitivity for operation in a tissue-equivalent dielectric medium. The simulated and measured results are all in close agreement.

Folded Loop Balanced Coplanar Antenna for WLAN Applications

A novel balanced rectangular loop antenna is proposed, having an ungrounded coplanar waveguide (CPW) feed configuration and a folded structure at both ends. This antenna is designed for operation over the 2.4 GHz and 5 GHz WLAN frequency bands. Bond-wire bridges are used along the CPW feed line to ensure the same potential across the CPW ground planes. The self-balancing structure that can be realized in a loop antenna offers operation without the need of a separate balun for connection to a RF source. A prototype of the optimized antenna with overall dimension of 31 mm × 16 mm × 3 mm was fabricated and tested. The calculated and measured results show good agreement, confirming good wideband characteristics with multiband operation. An example application of the proposed antenna is studied when used in handheld devices. The results show that this antenna has performance largely independent of perturbations of its associated ground plane, because the balanced feed created by the intrinsic balun structure minimizes ground plane currents.

An Active Microwave Sensor for Near Field Imaging

Near-field imaging using microwaves in medical applications is of great current interest for its capability and accuracy in identifying features of interest, in comparison with other known screening tools. This paper documents microwave imaging experiments on breast cancer detection, using active antenna tuning to obtain matching over a wide bandwidth. A simple phantom consisting of a plastic container with a low dielectric material emulating fatty tissue and a high dielectric constant object emulating a tumor is scanned between 4 and 8 GHz with a ultra-wideband microstrip antenna. Measurements indicate that this prototype microwave sensor is a good candidate for such imaging applications.

Skin pattern analysis for lesion classification using local isotropy.

Background/purpose: The observation that skin pattern tends to be disrupted by malignant skin lesions, but not by benign ones suggests that measurements of skin pattern disruption on simply captured white light optical clinical (WLC) skin images could be a useful contribution to a diagnostic feature set. Previous work, which generated a flow field of skin pattern using a measurement of local line direction and intensity, was encouraging. The aim of this paper is to investigate the possibility of extracting new features using local isotropy metrics to quantify the skin pattern disruption.