System och förfarande för att undvika oönskade inkommande anrop till en telefon

摘要

A method for avoiding undesired incoming calls provides a called party with an aural message indicating the telephone number of a calling party. The method includes the steps of: enabling the called party's telephone to ring in response to input of a ring signal during execution of a selective calling mode; connecting a signal path between the calling party's telephone and the called party's telephone; transmitting a voice message to the calling party requesting that the calling party input his or her telephone number and then input a predetermined key; determining whether a busy tone indicating that the calling party has hung up is detected; stopping the called party's telephone from ringing and disconnecting the signal path when the busy tone is detected; waiting for an input of a dual tone multi-frequency (DTMF) signal representative of the calling party's telephone number during a predetermined time period when the busy tone is not detected; storing the dual tone multi-frequency (DTMF) signal and then reading the dual tone multi-frequency (DTMF) signal upon completion of the input; providing the called party with an aural voice message representative of the calling party's telephone number; checking for an off-hook state of the called party's telephone; and stopping the called party's telephone from ringing and enabling execution of a conversation between the calling party and the called party when the off-hook state of the called party's telephone is detected.