An approach to cell signal coverage reliability in presence of different fading models
Recently, papers have appeared treating channels in presence of composite fading. Due to composite fading PDF complexity, gamma shadowing distribution instead of lognormal is proposed, to simplify analytical expressions. In order to estimate cell coverage in recent papers, only shadow fading model subdued to lognormal distribution was observed. In this paper, both mentioned models for cell coverage estimation are treated and compared: model with lognormal shadowing and model based on shadow fading which is subdued to gamma distribution (gamma shadowing). The impact of multipath fading, as part of path loss has been analyzed and expressed through composite fading model (Nakagami-m multipath/Gamma shadow fading). For all these models analytical closed forms for reliability parameters are derived (cell edge reliability and cell area reliability). Based on these results, reliability parameters in gamma shadowing and composite fading models are compared to a model which respects presence of lognormal shadowing, and presented in graphs. Also a simulation in order to compare different shadowing models and their impact on actual cell coverage has been made. In order to analyze signal coverage, cell radius estimation has been chose as relevant parameter for coverage verification and the effects of limited number of measured strength samples on cell radius estimation, using both proposed distributions, has been analyzed.