A radio communication system is disclosed. This system includes a wireless base station placed at an upper section of a communicating zone in a mobile unit such as an aircraft, multiple seat-rows arranged along a longitudinal direction in the communicating zone, and wireless terminals placed at each one of seats of the seat rows. Radio communication is done between the wireless base station and the wireless terminals. The wireless base station is placed on the ceiling at the forefront or at the extreme end of the communicating zone relative to the longitudinal direction of the seat rows.