This is basically the technology behind touch-tone dialing. The system used by touch-tone telephones, DTMF assigns a specific frequency (made up of two separate tones) to each key so that it can easily be identified by a microprocessor
DTMF signaling is multifrequency signaling for telephone systems. DTMF uses standard and set combinations of two specific voice band frequencies, one from a group of four low frequencies and the other from a group of four higher frequencies. DTMF signals, unlike dial pulses, can pass through the entire connection to the destination user, and therefore lend themselves to various schemes for remote control after the connection is established.
The system of tone pairs used in touch-tone devices.
The keypad signaling technology that generates two distinct tones when each key is pressed. This system of ?tone dialing? allows navigation of businesses? voice menus and other advanced calling services. All wireless phones use DTMF dialing. Also referred to as TouchTone.
A method used by the telephone system to recognise the keys pressed when dialling. Pressing a key on the phone's keypad generates two simultaneous tones, which are decoded by the exchange to determine which key was pressed.