Abstract: A portable electronic device for receiving an incoming call from an external network, includes an incoming call indication unit configured to indicate the incoming call, an illuminance measurement unit configured to measure illuminance of a peripherally of the portable electronic device, an acceleration detection unit configured to detect an acceleration of the portable electronic device, and a status determination unit configured to determine a status of the portable electronic device in accordance with the acceleration detected by the acceleration detection unit and the illuminance measured by the illuminance measurement unit. When the status determination unit determines that the acceleration detected by the acceleration detection unit is greater than a threshold value and a change in the illuminance measured by the illuminance measurement unit is greater than a predetermined value, the status determination unit controls the incoming call indication unit to change an output indicating the incoming call.

Abstract: A communication terminal apparatus, server, and radio communication system are provided that implement communication in a specific area subject to radio signal restrictions. The server 200 is equipped with a control section 201, a terminal control section 202, a database RAM section 203, a signal conversion control section 204, an ad hoc TX 205, an ad hoc RX 206, a radio TX 207, and a radio RX 208; mobile radio terminals 110 and 120 are equipped with a terminal function control section 111, a peripheral section 112, an ad hoc TX 113, an ad hoc RX 114, a radio TX 115, and a radio RX 116; and server 200 constructs a radio ad hoc network by means of terminal-server connection, and also transmits a control signal including inhibition of connection to a base station 300, and establishes ad hoc network connection on receiving a control signal from server 200.