Patent ID: 6751303
Filing Date: 2004-06-15
Classification: H04M

Abstract:
A multifrequency tone generator for sending data over a telephone voice channel comprising:an alphanumeric character generator for sequentially generating alphanumeric characters; a plurality of tone generators having a summed output for transmitting a tone signal selectably including a combination of standard DTMF frequency tones corresponding to each respective alphanumeric character; and a translation circuit responsive to an alphanumeric character from said character generator for activating said plurality of tone generators to simultaneously produce a predetermined combination of said DTMF frequency tones corresponding to each of said respective alphanumeric characters; wherein said DTMF frequency tones are comprised of eight distinct tone frequencies, wherein each distinct tone frequency represents a respective bit in an eight-bit word, and wherein said tone signal represents a particular word value in response to the presence or absence of each distinct tone frequency.