摘要 |
A dialing receiver (1) for determining multifrequency dialing signals on an incoming signal in a telecommunication switching system, including a sampling circuit (4) for taking N values of the incoming signal at a given sampling rate, where N is a positive integer; a zero value generator circuit (6) for supplementing at the given sampling rate the N samples with M successive zero values so as to yield N+M values, where M is a positive integer; a discrete Fourier transformation circuit (7) for performing a discrete Fourier transform (DFT) of said N+M values in accordance with the Goertzel algorithm; and a result evaluating circuit (8) for directly evaluating the results of the DFT processing of the N+M values without interpolation so as to determine the identity of the multifrequency dialing signals.
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