This paper presents the results of the refractivity statistics in the UAE (United Arab Emirates) for a period of 14 years (1990-2003). Six sites have been considered using meteorological surface data (Abu Dhabi, Dubai, Sharjah, Al-Ain, Ras Al-Kaimah, and Al-Fujairah). Upper air (radiosonde) data were available at one site only, Abu Dhabi airport, which has been considered for the refractivity gradient statistics. Monthly and yearly averages are obtained for the two parameters, refractivity and refractivity gradient. Cumulative distributions are also provided. © 2007 American Institute of Physics.

Abdulhadi Abu-Almal

Ajman University

Rami A. Kamel

K. Al-Ansari

Atmospheric propagation

Atmospheric refractivity index

refraction

Founded in 1988 as the first private institution of higher education in the United Arab Emirates and the Gulf region, Ajman University (AU) is now being recognized as an emerging leader on the global academic map.

The 2020 QS World University Rankings lists AU in the top 800 universities globally and among the top 10 worldwide for international students and faculty! The &ldquo;Top 50 Under 50&rdquo; QS Rankings names AU as one of the top 150 young universities in the world. Even our distinct location in the Dubai/Sharjah/Ajman corridor is ranked by QS as the 61st best student destination on the planet. Recently, Ajman University earned Five QS Stars in three ratings categories -- Social Responsibility, Inclusiveness and Learning Environment. We also garnered Four QS Stars for both Teaching and Internationalization.

AIP Conference Proceedings

A large set of 14 years of reliable local radiosonde meteorological data, from 1990 to 2003, has been used to calculate the effective Earth radius and point refractivity gradient in the United Arab Emirates. The obtained values are used to investigate their impact on the design of microwave links. The cumulative distribution of the refractivity gradient in the first 65 meters above the ground surface, the monthly distribution for the median value of the k-factor, as well as their comparison with the ITU-maps are provided. Both experimental and global standard values are applied to specific link budget calculations. © 2010 A. Abu-Almal and K. Al-Ansari.

Fulltext

International Journal of Antennas and Propagation

Calculation of effective earth radius and point refractivity gradient in UAE

Information based on 14 years of radio sounding data has been used to investigate the correlation between ground refractivity and refractivity gradient in Abu Dhabi city. The results of this analysis, which includes as well the statistical and worst month distributions of both parameters, are presented in this letter. © 2008 IEEE.

IEEE Antennas and Wireless Propagation Letters

Correlation between ground refractivity and refractivity gradient and their statistical and Worst Month distributions in Abu Dhabi

In communication system, signal propagates from the base station to the receiver as multitude of partial waves from different directions known as multipath propagation. This effect gives rise to fading of radio signal as the received signal strength decreases. In this …

EMPIRICAL CHARACTERIZATION AND MODELING OF FADE DEPTH DUE TO MULTIPATH PROPAGATION AT MICROWAVEBAND

A new simplified approach is proposed to evaluate the vertical refractivity profile within the lowest 1km of atmosphere from the analysis of surface refractivity $\bm{N}_{\bm{s}}$ in areas where upper-air data are not available. Upper-air measurements from the nearest available radiosonde location with similar surface profile to these sites are utilized. The profiles of $\bm{N}_{\bm{s}}$ and refractivity extrapolated to sea level $N_o$ obtained from surface meteorological data using both fixed stations and radiosonde are investigated and compared. Vertical refractivity gradient $\boldsymbol{\Delta} {\bm{N}}$ is evaluated at three atmospheric layer heights within the first kilometer above the ground in addition to propagation parameters relevant to each atmospheric layer. At six sites, different approaches are compared for the analysis of three important parameters; namely effective earth radius factor $k$ anomalous propagation probability parameter ${\boldsymbol{\upbeta}_0}$ and point refractivity gradient at 65m not exceeded for 1% of time $dN_1$. The ${\bm{k}}$-factor parameter is investigated using a new weighted average approach of $\boldsymbol{\Delta} {\bm{N}}$ at 65-m, 100-m, and 1-km layers above the ground. The results are compared with the latest ITU maps and tables for the same area.

IEEE Transactions on Antennas and Propagation

New Methodology for Predicting Vertical Atmospheric Profile and Propagation Parameters in Subtropical Arabian Gulf Region

Prevailing propagation phenomena in certain areas play a vital role in deciding terrestrial wireless systems performance. Vertical refractivity profile below 1 km is a critical parameter for designing reliable systems; noting that there is a shortage of upper-air data worldwide …

Analysis and modelling of the impact of anomalous propagation on terrestrial microwave links in a subtropical region, based on long-term measurements. Statistical …

Journal	AIP Conference Proceedings
Publisher	AIP
ISSN	0094243X
Open Access	No