I wonder if those models are actually being used by the 3G/4G operators in their planning, or if, in the end, they use their own empirical or ray-tracing models instead. I also have some questions regarding a few possible inconsistencies of those models. For instance, the mobile height gain of the ECC-33 model for medium cities is only positive for h>10^0.585=3.85m. Thus, for heights below that, the gain is actually a loss. At that height or lower, this leads to a total path loss that is larger in medium cities than in large cities! Since the model is supposed to be an extension of Okumura's, heights between 1 and 10 m should be compliant. Regarding the SUI model, it was derived from measurements at suburban environments. However, when compared to the COST-231 model at frequencies around 2 GHz, the results are only comparable if we consider the urban median path loss, thus disregarding the suburban gain correction factor. There is also an issue regarding the correction factor for the mobile antenna height: lots of papers that reproduce the model use expressions that seem to be inconsistent to me, like 20log(h/2000) or 10.8log(h/2000). Since the reference height is 2 m, the 2000 factor in the denominator doesn't make sense. I would very much appreciate a discussion on these models, in view of such apparent flaws or inconsistencies, at least as I perceive them.
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