Rapporteur: Mr. Ungvari, Gabor Antecedent:
Dual Tone Multi Frequency (DTMF) is an inband one out of four plus one out of four signalling system, primarily used from terminal instruments in telecommunication networks. The international recommendations which apply are ETSI
ES 201 235 as detailed in subclauses 6.2 and 6.3. For PCS 1900 for North America the Standards which apply
are operator specific.
This TS describes how Dual Tone Multi Frequency (DTMF) signals are supported in the 3GPP system.