Telephone line monitoring system
First Claim
1. A circuit for characterizing a sound signal by sampling the electrical signal produced by an electroacoustic transducer, comprising:
- (a) means for detecting the occurrence of each waveform composing a sampled electrical signal;
(b) means for measuring the wavelength of each waveform detected;
(c) means for counting the number of waveforms within each of a plurality of predetermined wavelength groupings; and
(d) means for characterizing the sound signal based on the counts of waveforms within the plurality of predetermined wavelength groupings and the distribution thereof.
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Accused Products
Abstract
A device for detecting voice signals in the presence of supervisory signals on a number of telephone lines so as to determine when machine-placed telephone calls have been answered. The device comprises a zero crossing detector for each telephone line monitored to determine the zero voltage crossings in the voltage of an incoming telephone signal, a latch associated with each detector for storing the occurrences of each zero voltage crossing detected and a microcomputer for processing the frequency-related information of the incoming telephone signals according to a voice detection algorithm. The voice detection algorithm comprises timer interrupt and analysis routines that direct the microcomputer to count the number of occurrences of different wavelengths of the waveforms composing an incoming telephone signal in determining the condition of response on a respective telephone line.
25 Citations
24 Claims
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1. A circuit for characterizing a sound signal by sampling the electrical signal produced by an electroacoustic transducer, comprising:
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(a) means for detecting the occurrence of each waveform composing a sampled electrical signal; (b) means for measuring the wavelength of each waveform detected; (c) means for counting the number of waveforms within each of a plurality of predetermined wavelength groupings; and (d) means for characterizing the sound signal based on the counts of waveforms within the plurality of predetermined wavelength groupings and the distribution thereof. - View Dependent Claims (2, 3, 4, 5)
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6. A transmission line monitoring system for determining the condition of response of incoming signals on a plurality of transmission lines, comprising:
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(a) means for detecting a particular polarity change of the voltage of the incoming signal over a selected interval on each transmission line; (b) means for measuring the wavelength of each waveform composing a respective incoming signal between each polarity change detected; (c) means for counting the number of waveforms composing a respective incoming signal within each of a plurality of predetermined wavelength groupings; and (d) means for processing the frequency-related information of the incoming signals from the means for detecting, the means for measuring and the means for counting to determine the condition of response on each of the transmission lines. - View Dependent Claims (7, 8, 9, 10, 11, 12)
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13. A telephone line monitoring system for determining the condition of response of incoming signals on a plurality of telephone lines, comprising:
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(a) a plurality of detectors which each receives the incoming signal of a respective telephone line and outputs a voltage pulse upon a particular polarity change of the voltage of the incoming signal over a selected interval; (b) a plurality of latch elements which each receive the output of a respective detector and stores the occurrence of a polarity change of the voltage of the respective incoming signal upon receiving a voltage pulse; and (c) a programmable logic element which samples the stores of the latch elements and, in response thereto, processes the frequency-related information of each waveform composing a respective incoming signal between each polarity change detected in order to determine the condition of response on each of the telephone lines. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20)
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21. A method for characterizing a sound signal by sampling the electrical signal produced by an electroacoustic transducer, comprising the steps of:
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(a) detecting the occurrence of each waveform composing a sampled electrical signal; (b) measuring the wavelength of each waveform detected; (c) counting the number of waveforms within each of a plurality of predetermined wavelength groupings; and (d) characterizing the sound signal based on the counts of waveforms within the plurality of predetermined wavelength the groupings and the distribution thereof. - View Dependent Claims (22, 23)
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24. A method for determining the condition of response of an incoming signal on a transmission line, comprising the steps of:
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(a) detecting a particular polarity change of the voltage of the incoming signal over a selected interval on the transmission line so as to determine if there are a sufficient number of polarity changes in the incoming signal to indicate that the transmission line is not silent; (b) detecting the number of occurrences of waveforms composing the incoming signal within each of a plurality of predetermined wavelength groupings so as to determine if there are a sufficient number of occurrences in each of the groupings to indicate that the incoming signal comprises a voice signal rather than a tone signal; and (c) repeating steps (a) and (b) until the same condition of response is indicated a predetermined successive number of times.
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Specification