POLARITY REVERSE SIGNAL GENERATING APPARATUS FOR TELEPHONE CHARGE ACCOUNTING IN INTERNET AND TELEPHONE CHARGE ACCOUNTING METHOD USING SAID APPARATUS

摘要

PURPOSE: An apparatus for generating a PRS(Polarity Reverse Signal) for the billing of telephone charges on the Internet and a billing method using the same are provided to carry out th billing of call charges on the Internet with an Internet telephone service system using an existing PBX(Private Branch eXchange). CONSTITUTION: A PRS generating apparatus(200) comprises a line seizure detection part(210), a polarity reversion part(240), a ringback tone signal generation part(220), and a control part(230). The line seizure detection part(210), connected with a calling subscriber telephone through a calling exchange(120), detects a hookup signal to check whether a line is seized. The ringback tone signal generation part(220) generates a ringback tone signal when the line is seized. The control part(230) receives a line seizure detection signal from the line seizure detection part(210) and drives the ringback tone signal generation part(220) to generate an internal ringback tone signal. Also the control part(230) compares the internal ringback signal with an external ringback tone signal transmitted from a called exchange(160) and judges whether the external ringback tone signal has been interrupted. In case that the external ringback tone signal has been interrupted, the control part controls the polarity reversion part(240) so as to generate a primary PRS. In case that it is detected that the seizure of the line has been released, the control part(230) controls the polarity reversion part(240) so as to generate a secondary PRS.