Abstract: A receiving modem is locked to a transmitting modem by employing a burst data and clock signal having an effective data rate compatible with the data rate of a receiving data set. The receive modem processes a transmitted analog signal as sent by the transmitting modem to provide a digital signal which is applied to an interpolation filter. The filter provides at an output a retimed signal. This retimed signal is monitored by a baud sync measurement circuit which detects the drift of baud transitions in the retimed interpolated signal to provide an output phase error signal. This phase error signal is used to control the filter coefficients of the interpolation filter for the next data block. In this manner the interpolation filter provides a newly retimed digital output signal according to the detected phase error. The output signal is demodulated and converted to a burst data and a burst clock signal for application to a receiving data set.

Abstract: An apparatus operates to identify the speech signal of an unknown speaker as one of a finite number of speakers. Each speaker is modeled and recognized with any example of their speech. The input to the system is analog speech and the output is a list of scores that measure how similar the input speaker is to each of the speakers whose models are stored in the system. The system includes front end processing means which is responsive to the speech signal to provide digitized samples of the speech signal at an output which are stored in a memory. The stored digitized samples are then retrieved and divided into frames. The frames are processed to provide a series of speech parameters indicative of the nature of the speech content in each of the frames.

Abstract: A digital divider with both integral and fractional division capabilities is provided by utilization of a counter and one decoder to trigger phase reversal and a second decoder to trigger short-cycling of the counter. The first decoder provides phase reversal to cause extra half pulses during the period established by the second decoder to thus create the fractional count needed for fractional division. A control input is included to select either whole number division or fractional division.

Abstract: A liquid crystal beam splitter includes a magnetic coil adapted to controllably orient, or tilt, the molecules of a layer of liquid crystal material and thereby detune the internal reflections of a polarized light beam component passing therethrough.

Abstract: A liquid crystal wave division device includes first and second polarization changing cells, the polarization changing cells utilize homogeneously aligned nematic liquid crystal material to effect the change of polarization of a preselected frequency portion of a multifrequency incident light beam.

Abstract: An apparatus for automatic speech recognition includes a plurality of processors, including template processors in which there are stored templates representative of both speech and non-speech sounds. Incoming sounds are continuously converted into digital signals in respective frames representative of speech and non-speech sounds, respectively. Sequences of such frames are compared with both the speech and non-speech templates to determine the closest matches. Endpoints of respective speech utterances are determined in response to the detection of respective non-speech-speech-non-speech sequences, whereupon such speech utterances are processed to recognize the same.

Abstract: A liquid crystal switching device includes first and second polarization reorienting cells disposed such that a polarized component of an incident light beam is incident normal to the cell.

Abstract: A liquid crystal switching apparatus includes a plurality of juxtaposed liquid crystal switching devices, each such device being capable of selectively reorienting the polarization of a polarized light beam component incident thereupon.

Abstract: An optical switching device includes first and second polarization changing cells, the polarization changing cells utilize twisted nematic liquid crystal material to effect the change of polarization. The resultant device exhibits reduced cross talk between the output ports thereof and requires less voltage to effect the switching of the output beam therebetween.

Abstract: A collimator includes a transparent base member defined by a planar surface and a spherical reflecting surface and includes an opening therein whereby an optical fiber may be terminated in the focal plane of the spherical reflecting surface.

Abstract: The invention provides a method and system for speaker enrollment, as well as for speaker recognition. Speaker enrollment creates for each candidate speaker a set of short acoustic segments, or templates, of phonemic duration. An equal number of templates is derived from every candidate speaker's training utterance. A speaker's template set serves as a model for that speaker. Recognition is accomplished by employing a continuous speech recognition (CSR) system to match the recognition utterance with each speaker's template set in turn. The system selects the speaker whose templates match the recognition utterance most closely, that is, the speaker whose CSR match score is lowest. The method of the invention incorporates the entire training utterance in each speaker model, and explains the entire test utterance. The method of the invention models individual short segments of the speech utterances as well as their long-term statistics.

Abstract: The spread spectrum communication system terminal comprises a first subsystem including a first arrangement to encode a locally generally digital data with an error correcting code, a second arrangement for spectrum spreading of the encoded locally generated digital data in at least one mode of operation of the communication system terminal, a third arrangement to receive remotely generated error correcting code encoded digitla data spectrum spread in the one mode of operation and a fourth arrangement to recover the remotely generated digital data. In addition, a second subsystem includes a fifth arrangement frequency hopping the encoded locally generated digital data prior to transmission to a remote location and a sixth arrangement frequency dehopping the encoded remotely generated digital data received from the remote location.

Abstract: A liquid crystal switching device utilizing the Brewster angle includes a Brewster angle polarizer disposed such that an incident light beam of the device impinges thereon at an angle approximately equal to the Brewster angle.

Abstract: A orderwire detector circuit operates to identify whether an orderwire signal is of a digital or of an analog format. The orderwire signal is conveniently combined with a high speed data signal. The circuit operates to filter the high speed data signal from the orderwire signal and then square and retime the orderwire signal by means of a stable clock source. The orderwire signal is delayed by one bit and these bits are then compared to determine whether or not over a long period a certain voltage exists. If the proper voltage level exists after a plurality of samples, then it is assumed that the orderwire signal is a digital signal. Depending on the voltage detected, at the end of a predetermined sampling period, one can therefore discriminate between a signal orderwire signal or a analog orderwire signal.

Abstract: A header for a wafer scale assembly includes a plurality of pins having end portions connectable to the wafer scale assembly. The end portions lie in a single plane that it substantially parallel to the plane of the wafer scale assembly.

Abstract: A liquid crystal optical switching device includes first and second transparent members configured to minimize both the path length and the number of internal reflections of a light beam traversing the device.

Abstract: A single fiber optical communication system (SFOCS) allows, in many operational scenarios, one-person deployment and recovery of optical links. Wavelength division multiplexing (WDM) is employed to provide full-duplex, bi-directional transmission. An optical subsystem achieves the wavelength multiplexing and demultiplexing while at the same time allowing for an unpolarized terminal design. Selection by the system of the WDM operating wavelengths between a pair of SFOCS terminals is performed without operator intervention.

Abstract: The method and associated system for providing increased information carrying capacity in optical fiber communication through frequency-division-multiplexing, comprising the steps of generating a reference optical beam, generating a plurality of closely spaced optical carriers having frequencies which are coherently related to the reference frequency of the reference optical beam and which are capable of drifting with the reference frequency while maintaining coherence therewith, and combining the plurality of closely spaced optical carriers to provide a multiplexed optical output beam.

Abstract: A liquid crystal optical switching device includes a plurality of ports each having associated therewith a blind hole receiving an optical fiber that is secured subsequent to the alignment thereof. The switching device is fabricated from inexpensive material and includes a minimum of optically flat surfaces.

Abstract: A method and apparatus for recognizing an unknown speaker from a plurality of speaker candidates. Portions of speech from the speaker candidates and from the unknown speaker are sampled and digitized. The digitized samples are converted into frames of speech, each frame representing a point in an LPC-12 multi-dimensional speech space. Using a character covering algorithm, a set of frames of speech is selected, called characters, from the frames of speech of all speaker candidates. The speaker candidates' portions of speech are divided into smaller portions called segments. A smaller plurality of model characters for each speaker candidate is selected from the character set. For each set of model characters the distance from each speaker candidate's frame of speech to the closest character in the model set is determined and stored in a model histogram. When a model histogram is completed for a segment a distance D is found whereby at least a majority of frames have distances greater D.