Abstract: An apparatus and method are described in a voice mail system for selectively storing faxes in a batch mailbox prior to printing at a facsimile machine in order to efficiently utilize the telephone connection between the voice mail system and the facsimile machine. The apparatus comprises a plurality of electronic mailboxes for the storage of facsimiles, a facsimile machine for receiving and printing facsimiles from the plurality of mailboxes, and a batch mailbox connected between the plurality of mailboxes and the facsimile for receiving and buffering the stored facsimiles and for sequentially transmitting the buffered facsimiles to the facsimile machine for printing. Facsimiles can be added to the batch mailbox during the printing of other facsimiles in the batch mailbox.

Abstract: Apparatus and methods are provided for non-simultaneously creating and storing in electronic format a composite voice/data message having a recorded voice message portion and a facsimile transmittal portion. The method provides for creating a voice message and sending a time-wise separated facsimile transmittal to a voice message/data storage system, and then associating the separate voice message and facsimile transmittal portions to form a composite voice/data message. The methods include a message identification scheme wherein a message identification number is assigned to the first-received message portion, and the caller is prompted to provide that message identification number in connection with the later-received message portion. Apparatus to accomplish these methods steps is also provided.

Abstract: A digital line card is provided for use in an electronic messaging system for enabling the receipt of voice and text or image data over a single communications port. The digital line card includes a digital signal processing integrated circuit, a microprocessor and a random access memory component for storing coding schemes employed by the digital signal processing integrated circuit. The digital line card is programmed to detect the presence of dual-tone multifrequency command signals in the incoming data stream, and to switch between voice and data processing responsive to the command signals.

Abstract: Dual tone multifrequency ("DTMF") signal pulses are detected and identified by subjecting the signal being analyzed to complex bandpass filtering for each of the two DTMF frequency bands. The envelope of the outputs of each of these filters are determined and subjected to a succession of different tests including a ripple or smoothness test to ensure adequate smoothness, a ratio test to ensure the occurrence of a step function, a twist test to ensure the proper amplitude ratio between the two bands, and a minimum energy test to ensure that the signal has sufficient energy. If the signal passes all of the detection tests, then the actual DTMF signal is identified by using the real and imaginary parts of each complex bandpass filter output to compute an associated complex phase angle, and comparing that phase angle to the corresponding phase angles for valid DTMF tones.

Abstract: Voice signal information in a telephone-type signal is detected by subjecting the signal to several tests such as a minimum energy test, an amplitude ratio test, and a sequencing test which ensures that the other tests have been satisfied for a sufficient length of time and/or sufficiently frequently over a predetermined time interval. A voice processing system such as a voice mail system may use the detection of voice as above to initiate the transmission of an announcement or message during an automatically placed telephone call.

Abstract: In a voice processing system employing the telephone communications network, any echo of an outgoing signal is substantially eliminated from the incoming signal by appropriately combining an appropriate version of the outgoing signal with the incoming signal so that there is destructive interference with any echo of the outgoing signal. To determine the appropriate version of the outgoing signal to be combined with the incoming signal, a brief training signal is applied to the telephone transmission line. The echo of this signal returned by the transmission line is stored and convolved with the time-inverse of the training signal to produce a function which approximates the impulse response of the transmission line. This function is thereafter used to produce the version of the outgoing signal which is combined with the incoming signal for echo cancellation.

Abstract: Digital samples of a voice signal are greatly compressed by filtering the samples to separate the information contained in them into several different frequency bands. In each of a succession of time intervals, the dominant filter output value is identified and converted to floating point form including an exponent and a generally truncated mantissa. All other filter output values for that time interval are also converted to floating point form having the same exponent. The mantissas are then further compressed by grouping values associated with each filter and again converting the mantissas in each group to floating point form having a common local exponent and submantissas. The Walsh-Haddamard transfer is also employed.

Abstract: Programmable logic gate structures employ pairs of complementary transistors. Programming of the transistors is accomplished either by voltage biasing a shared floating gate of a CMOS transistor pair or by providing a variable resistance serially or in parallel with each transistor. The variable resistance can be a fusible link or a semiconductor device having an alterable crystalline structure.

Abstract: A logic array which is small in size and low in power dissipation uses only one clock signal. The array is fully precharged by precharging a first portion and a second portion and then applying ground to the first portion while delayably applying the ground to the second portion. The address is read into the first portion during the precharging to speed up operation of the array.

Abstract: A programmable logic gate includes first and second complementary field effect transistors having gate terminals connected to receive a first input signal. A first variable resistance is connected in series with the first transistor, and a second variable resistance is connected in parallel with the second transistor. The variable resistances can be fusible links or variable resistance semiconductor devices. By increasing the resistance of the first variable resistance and decreasing the resistance of the second variable resistance, the input signal becomes ineffective in the logic gate. Conversely, by decreasing the resistance of the first variable resistance and increasing the resistance of the second variable resistance, the input signal becomes effective in operation of the logic circuit. In programming the transistors, one transistor is effectively disconnected from the gate and the complementary transistor is effectively shorted.

Abstract: An automatic supervisory control system is arranged to provide monitoring and supervisory functions in a noisy electrical environment over communication channels which are also noisy and generally highly congested. The system includes a central control station linked to a plurality of status stations by a single dedicated or shared radio channel, a plurality of telephone wire lines, or a combination of both. A coded signal is used to communicate status signals and command signals between the central control station and the status stations. The central control station includes the status display elements, the memory elements, an audible alarm indicator, printed status and command reports, a keyboard for data entry and a computer for controlling system operation.

Abstract: An automatic supervisory control system is arranged to provide monitoring and supervisory functions in a noisy electrical environment over communication channels which are also noisy and generally highly congested. The system includes a central control station linked to a plurality of status stations by a single dedicated or shared radio channel, a plurality of telephone wire lines, or a combination of both. A coded signal is used to communicate status signals and command signals between the central control station and the status stations. The central control station includes the status display elements, the memory elements, an audible alarm indicator, printed status and command reports, a keyboard for data entry and a computer for controlling system operation.

Abstract: A irrigation system for automatically irrigating an agricultural area having a plurality of fields for producing various crops includes a central station and a plurality of remote stations located in the fields. A computer with associated peripherals in the central station is loaded with an irrigation program defining a predetermined schedule for delivery of pre-established quantities of water to each field, the delivery of water can further be dependent on environmental conditions such as wind speed, temperature, humidity, and other factors. The computer via a communication path, such as a radio channel or three-wire circuit, sends coded command messages to selected remote stations for activating valves and pumps for delivering the pre-established quantities of water to the respective fields and continuously interrogates the remote stations for flow meter, water-pressure meter, environmental conditions and alarm information to diagnose proper operation and to monitor the delivery of water.

Abstract: An automatic supervisory control system is arranged to provide monitoring and supervisory functions in a noisy electrical environment over communication channels which are also noisy and generally highly congested.The system includes a central control station linked to a plurality of status stations by a single dedicated or shared radio channel, a plurality of telephone wire lines, or a combination of both. A coded signal is used to communicate status signals and command signals between the central control station and the status stations. The central control station includes the status display elements, the memory elements, an audible alarm indicator, printed status and command reports, a keyboard for data entry and a computer for controlling system operation.