Optimal LAP altitude for maximum coverage

Low altitude aerial platforms (LAP) have recently gained a significant popularity as key enablers for rapid deployable relief networks where coverage is provided by onboard radio heads. These platforms are capable of delivering essential wireless communication for public safety agencies in remote areas or during the aftermath of natural disasters. In this paper we present an analytical approach to optimize the altitude of such platforms to provide maximum radio coverage on the ground. Our analysis shows the optimal altitude is a function of the maximum allowed pathloss and of the statistical parameters of the urban environment as defined by the International Telecommunication Union. Furthermore, we present a closed form formula for predicting the probability of geometrical line of sight between the LAP and a ground receiver.