E. Ibrahim

A new design of horizontally polarizedand dual-polarized uniplanar conical beam antennas for HIPERLAN

It is shown that a conical beam 5.2-GHz antenna suitable for HIPERLAN application, but working in horizontal polarization, can be realized as a group of microstrip patch radiators in a ring formation. Layouts with three and four patches are described, and radiation patterns are found to agree well with predictions from a simple array model. The three-patch form is smaller and gives a closer approximation to an azimuth-independent pattern. Patterns are very similar to those achieved in vertical polarization with previously reported disk antenna realizations, giving peak radiation at about 50/spl deg/ elevation. Two methods of impedance matching are found to give satisfactory results. A dual-polarized conical-beam microstrip antenna, with a strictly uniplanar conductor pattern, is also presented and realized as an array of three square patches whose corners meet a central feed point. For the second polarization, the antenna functions as a series fed array. Fairly good conical beam patterns have been obtained, though only moderate polarization purity appears to be obtainable from three-element arrays.

Compact WLAN disc antennas

A novel conical beam patch antenna design, suitable for local area network applications, uses a central cylindrical connection from the disc to ground to achieve a large reduction in resonant size. Results on efficiency, bandwidth, and pattern are reported for several prototypes.

Conical beam, horizontally polarised antennas for HIPERLAN

It is shown that a conical beam 5.2 GHz antenna suitable for HIPERLAN application, but working in horizontal polarisation, can be realised as a group of microstrip patch radiators in a ring formation. Layouts with three and four patches are described, and radiation patterns are found to agree well with predictions from a simple array model. The three patch form is smaller and gives a closer approximation to an azimuth independent pattern. Patterns are very similar to those achieved in vertical polarisation with reported disc antenna realisations, giving peak radiation at about 50/spl deg/ elevation. Two methods of impedance matching are found to give satisfactory results.

An Evaluation of Spatial Modulation for MIMO Systems with QO-STBC

Simplified designs of multi-antenna systems with optimum efficiency are receiving attentions. Such simplicities also involve low cost architectures. In this study, we report an evaluation of a new multi-antenna scheme, namely, spatial modulation (SM) that is compared with quasi-orthogonal space time block codes (QOSTBC) scheme over Rayleigh fading channel. The SM scheme has been, earlier, compared with space time block codes (STBC) – a two antenna transmit diversity scheme that achieves full diversity when only two antennas are used. This is extended to QOSTBC scheme that absolves some decoding limitations to attain full diversity. It will be shown that, using the QOSTBC of similar architecture with the SM, even better performance can be achieved in favour of QOSTBC.

Neurological assessment of music therapy on the brain using Emotiv Epoc

A Cross-sectional study conducted to understand how music therapy can affect patients who suffer from memory loss conditions such as Dementia and Alzheimers disease. A comparative study is conducted between music and non-music questionnaires, to find patterns and indications of how music can contribute towards memory recall. The experiment is conducted using Emotiv Epoc headset which has 16 sensors that tracks the EEG of the brain and has software called Test Bench which records the data. This investigation strongly suggests that music is linked with memory and can affect memory recall.

Africa: cyber-security and its mutual impacts with computerisation, miniaturisation and location-based authentication

The state of insecurity occasioned by fraudulent practices in Africa has been of concern economically, both at home and abroad. In this paper, we propose ways to mitigate this problem, using Nigeria as a case study. Based on surveys in West Africa, the paper examines the security situation in the continent and its mutual impacts with computerisation, miniaturisation and Location-Based Authentication (LBA). It was discovered that computerisation and miniaturisation had negative effects on cyber-security, as these were being exploited by fraudsters, using advance fee fraud; called 419. As a countermeasure, the paper examines the possibility of using LBA and digitisation of the GSM Mobile country codes down to city/area codes along with GSM/GPS authentications. These could also be combined with the use of a web-based Secret Sharing Scheme for services with very high security demands. The challenges of roaming were also examined and considered to be of negligible impact.

A Staircase-Shaped DGS Structure Monopole Antenna for UWB Operations

This paper presents a novel, physically compact, miniaturized, ultra-wideband (UWB) monopole antenna design, which utilizes a defected ground structure (DGS). The defected ground design is realized as a spiral staircase-shaped pattern, and the optimized antenna volume is 26 × 25 × 1.6 mm3. The resultant antenna operates over the full UWB frequency range from 3.1 GHz to 10.6 GHz, with predicted gains in the range 0.1 dBi to 3.36 dBi across the band.

Nigeria: Cyber Space Security vis a vis Computerisation, Miniaturisation and Location-Based Authentication

The degree of insecurity occasioned by fraudulent practices in Nigeria has been of great concern economically, especially as it relates to overseas transactions. This paper was designed to mitigate this problem for Nigeria and countries with similar dispositions. Based on a survey involving field trip to Nigeria, the paper examines the general security situation in Nigeria and its mutual impacts with computerisation, miniaturisation and Location-Based Authentication (LBA). It was discovered that both computerisation and miniaturisation had some negative effects on cyber-security, as these were being exploited by fraudsters, especially using ‘advance fee fraud;’ popularly called 419. As a countermeasure, the research examined the possibility of using LBA and further digitisation of the GSM Mobile country codes down to City/Area codes along with GSM Mobile/Global Positioning System (GPS) authentications. Where necessary, these could be combined with the use of a web-based Secret Sharing Scheme for services with very high security demands. The anticipated challenges were also examined and considered to be of negligible impacts; especially roaming.