MOBILE COMMUNICATION SYSTEM

PURPOSE:To utilize the titled system as a telephone system for aircraft by deciding the position of a mobile station depending on the reception level of a radio wave from the mobile station and switching a high gain antenna or an antenna for blind zone for the changeover. CONSTITUTION:An aeronautical mobile station 10 communicates with a transmitter-receiver 4 connected normally to a high gain antenna 1. The high gain antenna 1 is an antenna having a sharp horizontal directivity and the reception level is decreased rapidly when the aeronautical mobile station approaches a base station. A base station control section 7 detects it depending on the reception level that the aeronautical mobile station 10 is approaching a blind zone and activates a transmitter-receiver 6 for blind zone and stops the operation of the transmitter-receiver 4 used so far and connects a communication line with a control station 8 to the transmitter-receiver 6 for blind zone. An antenna 2 for blind zone has its directive characteristic in upper front direction and the blind zone of high gain antenna 1 is used for the coverage of radio communication. Thus, the blind zone is eliminated and the effective utilization to aeronautical telephone systems is attained.