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: 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 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.