Communication system of portable communication terminal, incoming call control system of portable communication terminal and incoming call notifying device of portable communication terminal

An incoming call control system of a portable communication terminal, comprising an incoming call notifying device, wherein when an incoming call is received by the portable communication terminal, an ID signal is transmitted from the portable communication terminal via radio to the incoming call notifying device;

• and the incoming call notifying device performs an incoming call notifying operation after the incoming call notifying device detects the ID signal transmitted by the portable communication terminal, wherein
• a data format of the ID signal transmitted from the portable communication terminal to the incoming call notifying device has a bit synchronizing frame for use in clock regeneration by the incoming call notifying device,
• a word synchronizing frame for use in frame synchronization for the acquisition of ID information, and
• an ID information frame for loading ID information stored in the portable communication terminal.

An incoming call notifying device of a portable communication terminal wherein when an incoming call is received by the portable communication terminal, an ID signal is transmitted from the portable communication terminal via radio to an incoming call notifying device;

• and the incoming call notifying device performs an incoming call notifying operation after the incoming call notifying device detect the ID signal on receipt of the ID signal intermittently, wherein
• the incoming call notifying device is provided with
• a received data detection unit for detecting a digital data on receipt of a radio wave from the portable communication terminal,
• a control unit for comparing the ID data detected by the received data detection unit with the data prestored in a memory so as to control the incoming call notifying device on the basis of results of comparison and identifying the data detected by the received data detection unit stepwise before controlling the incoming call notifying device,
• a timer for outputting a transfer signal for switching the received data detection unit from a sleep mode to an operating mode in a predetermined cycle, wherein
• when the timer outputs the transfer signal, the control unit switches the received data detection unit from the sleep mode to the operating mode and identifies the data detected by the received data detection unit stepwise and when the data needs not detection, the control unit returns the received data detection unit to the sleep mode from the operating mode.

An incoming call notifying device of a portable communication terminal wherein when an incoming call is received by a portable communication terminal, an ID signal is transmitted from the portable communication terminal via radio to the data reception unit of the incoming call notifying device;

• and the incoming call notifying device performs an incoming call notifying operation after detection of the ID signal, characterized in that
• an antenna for use is such that the open f ace of a loop and the surface of a grounded board are set parallel to each other;
• the open area of the loop is set equal to or greater than the area of the grounded board;
• and the distance between the loop and the grounded board is set not less than {fraction (1/40)} of the wavelength.