A Comprehensive Review of the Site Diversity Technique in Tropical Region: Evaluation of Prediction Models Using Site Diversity Gain of Greece and India

Abstract

my).⁞ABSTRACT The satellite signal deteriorates as it propagates from the source to the ground antenna on the surface of the earth. While some losses involving the amplitude and energy of the signal are unavoidably recovered due to the long slant path through the atmosphere, the impairment due to precipitation, especially rain, can be mitigated. Site diversity is one of the ways to obtain a less rain-attenuated signal, simply by preparing the other site to receive a link similar to that of the main site. Dual site diversity is common in practice with a site separation distance of at least a rain cell extent. This article presents an overview of the site diversity concept and a description of all parameters involved regarding the factor that contributed to the gain, which has been used as a performance metric to measure the effectiveness of a site diversity scheme. A detailed assessment of the capability of the gain prediction model is presented using site diversity experimental data conducted in two different climatic groups, namely, Greece in a temperate region and India in a tropical climatic region. The models involved in the evaluation were the ITU-R, Hodge, and Panagopoulos models, which were validated using temperate regional data, and the Semire and Yeo models, which were validated using tropical regional data. The observations of model behavior revealed that the Semire and Yeo models of the tropics were consistent with the measured gain obtained from India and Greece, respectively; thus, this demonstrated that the direction of future prediction models should consider both climates in the validation process.⁞INDEX TERMS Signal degradation, model evaluation, tropical region, rain-induced attenuation, atmospheric effect.

A Review on Rain Signal Attenuation Modeling, Analysis and Validation Techniques: Advances, Challenges and Future Direction

“…ST, on the other hand, is a mild shower that lasts longer and is more widespread. Storm-wind rain is a rainstorm characterized by intense clouds and severe aftereffects in some local locations for brief periods [77,78]. Hence, since all the rain types are defined within the distance domain called rain cells, any two links located at different places (or cells) will experience different levels of attenuation while receiving signals from the same source [79].…”

The Horizontal Rain-Cell Span and Wind Impact on Multisite Diversity Scheme in a Tropical Region during El-Niño and La-Niña

“…As the rain-induced attenuation is getting worse, the least-attenuated signal from the diverse site would be routed to the host and used in the operation. Therefore, the backup site should be selected properly, which gives many benefits to the host [ 7 , 8 ].…”

Embracing Small Satellites Into Future 6G Inclusive IoT Coverage: A Deployment of Diversity-Based Theoretical Framework

“…Receiver-based diversity combining is a well-known technique which has been deeply studied, maturely developed, and widely applied in different mobile communication systems. For example, a site-based diversity was overviewed in [11] as an effective scheme to mitigate rain attenuation effects on satellites signals at tropical climates, a cluster diversity combining was suggested to accelerate the delivery of indoor autonomous vehicles' emergency alerts with less required rebroadcasts according to [12], a single-input multiple-output (SIMO) structure was presented to combine two downlinks from two receiving nodes by a Maximal Ratio Combiner (MRC) as a part of the study presented in [13] to improve the performance of a nonorthogonal multiple access (NOMA) network, the deep fading consequences inside tunnels were suppressed by utilizing multiple properly spaced antennas in a diversity scheme as confirmed in [14], MRC was deployed to enhance the performance by combining faded signals received by spatially distributed cellular base stations as depicted in [15], and the study conducted in [16] concluded that increasing transmit and receive antennas improved the performance in high-mobility communication systems even when rapidly switching channels.…”