A base station device for performing air-to-ground communication with an aircraft terminal device for air-to-ground communication placed in an aircraft and for performing ground-to-ground communication with a ground terminal device placed on a ground location, the base station device comprising: an air-to-ground communication device configured to perform communication with the aircraft terminal device by using a vertically-oriented antenna adapted for air-to-ground communication; a ground communication device configured to perform communication with the ground terminal device by using a horizontally-oriented antenna adapted for ground-to-ground communication; and a controller configured to manage a vertically-oriented cell formed by the vertically-oriented antenna and a ground cell formed by the horizontally-oriented antenna with respective IDs used to identify the vertically-oriented cell and the ground cell, and to control communication with a counterpart terminal device (2, 4) such that, if the counterpart terminal device is an aircraft terminal device, the controller is adapted to cause the counterpart terminal device to connect to the vertically-oriented cell, otherwise the controller is adapted to cause the counterpart terminal device to connect to the ground cell, wherein the controller is configured such that, when the ground communication device or the air-to-ground communication device receives a message transmitted from the counterpart terminal device (2, 4), the controller is adapted to determine whether or not the counterpart terminal device (2, 4) is an aircraft terminal device based on prescribed information included the received message, characterized in that the base station device further comprises a network communication device configured to receive an emergency alert from an emergency alert delivery device via a core network, wherein the controller is configured such that, when the network communication device receives the emergency alert, the controller is adapted to prevent the aircraft terminal device as the counterpart terminal device from connecting to the vertically-oriented cell. an air-to-ground communication device configured to perform communication with the aircraft terminal device by using a vertically-oriented antenna adapted for air-to-ground communication; a ground communication device configured to perform communication with the ground terminal device by using a horizontally-oriented antenna adapted for ground-to-ground communication; and a controller configured to manage a vertically-oriented cell formed by the vertically-oriented antenna and a ground cell formed by the horizontally-oriented antenna with respective IDs used to identify the vertically-oriented cell and the ground cell, and to control communication with a counterpart terminal device (2, 4) such that, if the counterpart terminal device is an aircraft terminal device, the controller is adapted to cause the counterpart terminal device to connect to the vertically-oriented cell, otherwise the controller is adapted to cause the counterpart terminal device to connect to the ground cell, wherein the controller is configured such that, when the ground communication device or the air-to-ground communication device receives a message transmitted from the counterpart terminal device (2, 4), the controller is adapted to determine whether or not the counterpart terminal device (2, 4) is an aircraft terminal device based on prescribed information included the received message, characterized in that the base station device further comprises a network communication device configured to receive an emergency alert from an emergency alert delivery device via a core network, wherein the controller is configured such that, when the network communication device receives the emergency alert, the controller is adapted to prevent the aircraft terminal device as the counterpart terminal device from connecting to the vertically-oriented cell.