A call progress analysis system is generic to any telecommunications system with which it is used due to configurable detection parameters. A signal on a channel of the telecommunications system is detected in intervals of changing frequency composition and compared to stored pattern descriptors, each of which defines a different call progress signal. The pattern descriptor parameters are configurable and include values for identifying tones present in the signal and the relative cadences of those tones. A separate list of tone descriptors, referenced by the pattern descriptors, are configurable and identify different tones by signal power at different frequencies. A progressive matching technique compares each successive interval of the detected signal to the successive intervals defined by each pattern descriptor, and generates a possibility list of pattern descriptors which may match the detected signal. As each interval is detected and compared to the corresponding intervals of the pattern descriptors, more descriptors are removed from the possibility list, until finally only one matching descriptor remains. Further matching may be required if desired, to ensure that the pattern continues to match for a minimum number of intervals.
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