Telephonic communications – Centralized switching system – Switching controlled in response to called station...
Patent
1995-04-11
1998-03-17
Zele, Krista M.
Telephonic communications
Centralized switching system
Switching controlled in response to called station...
379 67, 379 89, 379283, 379351, H04M 100
Patent
active
057296022
ABSTRACT:
A system for detecting the presence, in an audio channel which may contain voice signals, of a tone at a frequency selectable from among a plurality of selectable frequencies. A bandpass filter receives the audio input; its center frequency is selectable in response to a control signal. A first detector circuit provides from the output of the bandpass filter an output signal when a tone containing substantial energy at about said center frequency is input to the filter. A band-stop filter having the same center frequency as the bandpass filter also receives the input audio; a second detector circuit demodulates and thresholds the band-stop filter output. A micro-controller provides the control signal to set the center frequencies of said filters in response to user selection and analyzes the detector circuit output signals and generates an output signal when the output signal from the first detector circuit indicates the presence of a tone for a predetermined time and the output signal from the second detector circuit indicates the lack of presence of substantial energy at frequencies other than the center frequency for the same predetermined time. Optionally, the invention is applied to substitute for the operator a more pleasing signal than a tone at said filter center frequency.
REFERENCES:
patent: 4410762 (1983-10-01), Ecklund
patent: 4484035 (1984-11-01), Graham et al.
patent: 4623761 (1986-11-01), Winter et al.
patent: 4667065 (1987-05-01), Bangerter
patent: 4669114 (1987-05-01), Reesor et al.
patent: 4771449 (1988-09-01), Kiko et al.
patent: 5459781 (1995-10-01), Kaplan et al.
patent: 5483579 (1996-01-01), Stogel
patent: 5519774 (1996-05-01), Battista et al.
Schnell Herman
Sullivan Thomas
Comex Systems, Inc.
Saint-Surin Jacques M.
Zele Krista M.
LandOfFree
Programmable multi-tone voice message starting system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Programmable multi-tone voice message starting system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Programmable multi-tone voice message starting system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-965071