Air traffic control communication system employing high altitude platform station (HAPS)

There have been few recent studies on aeronautical communication network that employs mobile ad hoc network. These studies expect to setup a multi hop communication network among the aircrafts in the airspace. However, they have just only focused on the routing protocols which are applied for guiding the packet (aircraft position information) until the air traffic control station (ATC). This obligation prohibits any setup for direct aircraft to aircraft communication which is essential to the communication for future free flight concept. In this paper, we introduce a reliable avionic network architecture constituted not only by the aircrafts, HAPS, ATC stations. In this architecture, the aircraft position information reports will be routed to the relevant ground station by multi-hop relaying through other aircrafts or HAPS. The availability of HAPS will set up the second fixed backbone nodes in the air and aircrafts are relay nodes. In this paper, we further provide various evaluations through computer simulations firstly with CSMA/CA access scheme with the important factors such as the relay capability of the aircraft position information via system and the total accumulated delay time due to relaying processes. These evaluations are conducted in two cases of relaying network configurations. In the first case, data packets are routed through aircraft to aircraft without the availability of HAPS and the second one in which HAPS are available with a varying density. In addition, the evaluations have been conducted at different aircraft densities.