Abstract
Interest in high-altitude platforms (HAPs) has been increasing recently, especially with the rapid technical development in solar panels' efficiency, energy storage, antenna design, and lightweight materials for aircraft parts. These factors make high-altitude platforms more applicable in a wide variety of military, security, relief, and civilian applications. In this paper, we suggests using the LoRa system mounted on a HAPS aiming to cover larger areas. Also, we present the link budget of a LoRa operating in the 868 MHz band to accounting the received signal strength at the ground station. The path loss will be calculated based on the elevation angle between the ground station and the HAP for different urban scenarios. Finally, the altitude of the HAP will be optimized to provide maximum radio coverage for each urban environment alongside with different LoRa spreading factors.