Fast last digit detection of a dialed telephone number

Claim 1

A method of efficiently recognizing when the last digit of a DTMF telephone number has been dialed comprising the steps of: (a) monitoring a series of early successive dialed digits; (b) calculating the time gaps between said early successive dialed digits; (c) comparing the time gaps calculated in step (b) with a predetermined digit time gap applicable to computer generated DTMF dialing to determine whether each calculated time gap and said predetermined digit time gap are within a preset time range; (d) determining that said telephone number is (i) computer generated when each calculated time gap is less than the sum of said predetermined digit time gap and said preset time range, and (ii) manually generated when one of said calculated time gaps is greater than or equal to the sum of said predetermined digit time gap and said preset time range; (e) setting a time delay equal to (i) a first value when said telephone number is determined to be manually generated, and (ii) a second value, less than said first value, when said telephone number is determined to be computer generated; (f) monitoring digits dialed subsequent to said early dialed digits; and (g) signaling the end of said telephone number dialing when said set time delay expires without receipt of a digit dialed subsequent to said early dialed digits.

Claim 2

A method of efficiently recognizing when the last digit of a DTMF telephone number has been dialed comprising the steps of: (a) monitoring a series of early successive dialed digits; (b) calculating the time gaps between said early successive dialed digits; (c) comparing the time gaps calculated in step (b) with a predetermined digit time gap applicable to computer generated DTMF dialing to determine whether each calculated time gap and said predetermined digit time gap are within a preset time range; (d) determining that said telephone number is (i) computer generated when each calculated time gap is less than the sum of said predetermined digit time gap and said preset time range, and (ii) manually generated when one of said calculated time gaps is greater than or equal to the sum of said predetermined digit time gap and said preset time range; (e) setting a time delay equal to (i) a first value when said telephone number is determined to be manually generated, and (ii) a second value, less than said first value, when said telephone number is determined to be computer generated; (f) monitoring digits dialed subsequent to said early dialed digits; and (g) signaling the end of said telephone number dialing when said set time delay expires without receipt of a digit dialed subsequent to said early dialed digits.

Claim 8

A method of signaling an end of a dialed telephone number comprising the steps of: (a) calculating actual time gaps between early successive received digits of said dialed telephone number; (b) comparing said actual time gaps to a standard time gap applicable to computer generated digits; (c) determining whether said dialed telephone number is being manually or computer generated in accordance with the results of said comparing step; (d) setting a time delay representative of the expected time spacing between successive digits for the type of dialing determined to be in progress in step (c); and (e) signaling receipt of the last dialed digit in said telephone number when said set time delay expires without receipt of a dialed digit.

Claim 9

A method of signaling an end of a dialed telephone number comprising the steps of: (a) calculating actual time gaps between early successive received digits of said dialed telephone number; (b) comparing said actual time gaps to a standard time gap applicable to computer generated digits; (c) determining whether said dialed telephone number is being manually or computer generated in accordance with the results of said comparing step; (d) setting a time delay representative of the expected time spacing between successive digits for the type of dialing determined to be in progress in step (c); and (e) signaling receipt of the last dialed digit in said telephone number when said set time delay expires without receipt of a dialed digit.

Claim 15

A method of efficiently recognizing a last digit of a standard DTMF dialed telephone number comprising the steps of: timing relative to each other a selected number of successive received digits of said telephone number; comparing the timing of said successive received digits with digit spacing patterns applicable to computer generated digits to determine whether the telephone number is being dialed manually or automatically; and determining when said last digit has been dialed when a succeeding digit is not received within a predetermined time interval, said predetermined time interval being a function of whether it has been determined that the telephone number is being dialed manually or automatically.

Claim 16

A method of efficiently recognizing a last digit of a standard DTMF dialed telephone number comprising the steps of: timing relative to each other a selected number of successive received digits of said telephone number; comparing the timing of said successive received digits with digit spacing patterns applicable to computer generated digits to determine whether the telephone number is being dialed manually or automatically; and determining when said last digit has been dialed when a succeeding digit is not received within a predetermined time interval, said predetermined time interval being a function of whether it has been determined that the telephone number is being dialed manually or automatically.