Generating Dual Tone for Creating Our Own Communication Channel
International Journal of Innovative Science and Modern Engineering (IJISME), 1 (8):
29-31 (July 2013)Abstract
When we dial land number or Mobile number on our phones , it gives a ring to the person we need to contact, this is possible by the concept of DUAL TONE – MULTIPLE FREQUENCY (DTMF). The DTMF is a popular signalling method between telephone and switching centres .It is also used for signalling between the telephone network and computer network. DTMF signals are the superposition of two sine waves with different frequencies. In this the key stroke we give is converted to frequency and this sine wave is decode by the decoder and switching centre connects our line to the desired destination. In recent days when we call to customer care , instead of person of person computer is able to solve our query ,this is possible by programming the sound card of computer with the frequencies generated by phone. This paper mainly deals about dtmf, their working, verification using mat lab and their application.