Abstract: A system and a method for code division multiple access (CDMA) communication. The system includes fixed terminals communicating with a central base station. The terminals in protection sectors of each sector are configured to employ codes from different sets of codes to overcome potential mutual interference between sectors on account of antenna radiation pattern roll-off. The remaining codes, preferably the majority of the available codes, are used in any one of a plurality of basic sectors, each of which separates the protection sectors of a respective sector. For an even number of sectors in a cell, the available codes are partitioned into three groups, two for the protection sectors and one for the basic sectors. For an odd number of sectors in a cell, the available codes are partitioned into four groups, three for the protection sectors and one for the basic sectors. Protection sectors are relatively narrow but broad enough to counteract the potential mutual interference between sectors.

Abstract: Methods and communication networks having a plurality of connection-oriented switches in which administrative weights are assigned based on link call blocking probabilities. Three assignment schemes include, first, a solution that can be built in the switch software of sufficiently similar switches to enable the switches to determine administrative weights for their links. The second and third schemes employ administrative weight management stations. The second scheme uses an administrative weight management station that operates to enhance total network revenue or throughput in a communication network in which all of the switches implement a certain type of accounting management information databases (MIB). The third scheme uses an administrative weight management station that computes administrative weights for switches that do not have the capability for the second scheme, but which employ appropriate MIBs.

Abstract: A system, a transceiver, and methods for code division multiple access (CDMA) communication. The system includes first and second code division multiple access transceivers. The first code division multiple access transceiver has a plurality antennas disposed to provide transmission via a plurality of paths and the second code division multiple access transceiver has a rake arrangement for processing a plurality of signals received at the rake arrangement with differing delays or other characteristics. A driving arrangement is provided for causing the first code division multiple access transceiver to use a relative few, e.g., one, of the plurality of antennas. When, however, an indication is obtained that an adequate number of resolvable signals are likely not received at the rake arrangement of the second transceiver, a circuit switches the driving arrangement to cause the first transceiver to use more of the plurality of antennas.

Abstract: An arrangement and a method for monitoring and controlling an optical mechanical switch, which may include one or more microelectromechanical switches. In communication using the arrangement or the method, independently of any customer signal, a modulated optical signal is generated at wavelengths, both modulation and optical, that are out-of-band with respect the wavelengths of any transmission signals that may appear. The modulated optical signal is directed toward the optical mechanical switch, and system control parameters are changed to maximize a detected signal after passage through the optical mechanical switch. Any remnants of the modulated optical signal may be removed before arriving at any customer-related terminal. Optical cross-connect switching circuits are exemplary circuits in which the invention may be applied. The modulated optical signal is inserted before or during the transmission of any transmission signal.

Abstract: A microelectromechanical system in which, operationally independent of the movable element and the component for moving it, a microelectromechanical sensor senses the position of the movable element. The microelectromechanical sensor adjoins the movable element, at least in part, and may be a strain gage, or a gage of a capacitive, piezoelectric, piezoresistive, or pressure type, among others. The resulting signal is fed back to control the component for moving the movable element. In an array of movable elements and sensors, the signal of each sensor is specific to one movable element.

Abstract: A method and an electronic data processing apparatus for wave synthesis that retains the true qualities of naturally occurring sounds, such as those of musical instruments, speech, or other sounds. Transfer functions representative of recorded sound samples are pre-calculated and stored for use in an interpolative process to generate a transfer function representative of the sound to be synthesized. The preferred transfer functions are Chebyshev polynomial-based transfer functions, which assure a highly predictable harmonic content of synthesized sound. Output sound generation is driven by time domain signals produced by reconversion of a sequence of interpolated transfer functions. Non-harmonic sounds are synthesized using multiple frequency inputs to the reconverting (waveshaping) stage, or by parallel waveshaping stages. Speech sibilants and noise envelopes of instruments are synthesized by the input of noise into the waveshaping stage by modulation of a sinusoid with band-limited noise.

Abstract: An electronic data mining process for mining from an electronic data base using an electronic digital computer a listing of commercially useful information of the type known in the art as an association rule containing at least one uninstantiated condition. For example, the commercially useful information may be information useful for sales promotion, such as promotion of telephone usage. The computer retrieves from the database a plurality of stored parameters from which measures of the uninstatiated condition can be determined. The computer uses a dynamic programming algorithm and iterates over intervals or sub-ranges of the parameters to obtain what is called an at least partially optimized association rule, as optimized intervals or sub-ranges of at least some of the retrieved parameters, for example, time intervals of high usage of certain types of telephone connections. These optimized intervals are provided as the listed commercially useful information.

Abstract: A planar lightguide circuit having a grating coupler to backward couple a elected wavelength from among a plurality of optical signals. A cascaded arrangement of such couplers provides multiplexing or demultiplexing. In its simplest form, a planar lightguide circuit has in close proximity on a substrate first and second planar lightguides having differing effective indices of refraction in a first region. Preferably, the lightguide having the higher effective index of refraction parallels in dose proximity in the first region the lightguide having the lower effective index of refraction, the latter propagating a plurality of multiplexed signals. Typically, this relationship of effective indices of refraction is provided by differences in widths of the lightguides rather than by differences in material composition or differences in layer thicknesses. Optionally, all inputs and outputs have appearances at a common edge of the substrate.

Abstract: A method for applying forward error correction in a transmission network includes the steps of choosing one of a plurality of possible error correction codes, using an appropriate field to encode a complete forward-error-correcting (FEC) code algorithm in each FEC packet to be transmitted. The packet stream, consisting of media packets and FEC packets can be sent to both FEC-capable and FEC-incapable receivers. Decoding methods are independent of the forward-error-correcting code transmitted. The sender can adapt the forward-error-correction code algorithm and the degree of error correction provided on a one-time basis or even more dynamically. Decoding and recovery at the receiver require no prior notification from the sender. Applying the FEC code algorithm to decode includes interrogating the bits in an offset bit mask in each FEC packet to yield links with media packets, and applying other fields of the FEC header to obtain instructions to recover lost data in one of the media packets.

Abstract: Speaker independent recognition of small vocabularies, spoken over the long distance telephone network, is achieved using two types of models, one type for defined vocabulary words (e.g., collect, calling-card, person, third-number and operator), and one type for extraneous input which ranges from non-speech sounds to groups of non-vocabulary words (e.g. `I want to make a collect call please`). For this type of key word spotting, modifications are made to a connected word speech recognition algorithm based on state-transitional (hidden Markov) models which allow it to recognize words from a pre-defined vocabulary list spoken in an unconstrained fashion. Statistical models of both the actual vocabulary words and the extraneous speech and background noises are created. A syntax-driven connected word recognition system is then used to find the best sequence of extraneous input and vocabulary word models for matching the actual input speech.

Abstract: There is disclosed a method and apparatus for data coding for image transmission or storage in which vector quantization enables good image quality at reduced transmission or storage bit rates by directly employing spatial contiguity with a prior block of data, or a one-row-prior block of data in a way that directly controls intensity continuity between spatially close pixels of the adjacent blocks in two directions. The technique includes both "side-match" (no overlap) and "overlap-match" vector quantization. The technique is relative demanding of memory space and logic capacity in the encoding of the image information; but the decoding can be relatively simple and thus is well adapted for archiving and subsequent retrieval of two-dimensional information.

Abstract: An arrangement and a method for recognizing a speech pattern employs a quick initial processing based upon subpatterns of speech features from which time-sequence information has been removed is followed by more conventional processing of a plurality of the best candidates. The initial processing, or pre-selection, eliminates large numbers of unlikely candidates, the best candidates being retained by setting an empirically determined threshold for similarity, as measured by a suitable distance measurement. To facilitate retrieving the complete speech feature patterns including time-sequence information for the subsequent processing, the code books of the subpatterns also contain associated indices pointing to the corresponding complete patterns.

Abstract: A speech recognition system and technique of the acoustic/phonetic type is made speaker-independent and capable of continuous speech recognition during fluent discourse by a combination of techniques which include, inter alia, using a so-called continuously-variable-duration hidden Markov vodel in identifying word segments, i.e., phonetic units, and developing proposed phonetic sequences by a durationally-responsive recursion before any lexical access is attempted. Lexical access is facilitated by the phonetic transcriptions provided by the durationally-responsive recursion; and the resulting array of word candidates facilitates the subsequent alignment of the word candidates with the acoustic feature signals. A separate step is used for aligning the members of the candidate word arrays with the acoustic feature signals representative of the corresponding portion of the utterance.

Abstract: There is disclosed a system for providing an economical telephone toll service in which a telephone subscriber selects the economical service by, for example, sending an appropriate signal, and then dials his directory assistance call or other telephone toll call. After the caller's options are determined and typically before signaling for the call is commenced, a recorded-announcement of an aural or visual nature is connected to the subscriber's line, the announcement consisting of at least one advertisement. The advertisements are selected from a databank according to some predetermined technique of selection, which may include any number of factors or features to make the service attractive to subscribers and of a nature to make the service also sufficiently rewarding to advertisers.

Abstract: A speech analyzer is adapted to produce speech parameter signals from a Pth order autocorrelation analysis of a speech pattern in a digital signal processor. The analyzer includes a plurality of memories of predetermined arrangement to store feature vector signals used in the analysis, a single set of coded signals for controlling the analysis, and a memory address processor for addressing the feature vector signal memories. In each iteration of the analysis, at least one speech parameter signal is produced by the digital signal processor responsive to the same set of control signals and the feature vector memory addressing signals.

Abstract: There are disclosed a method and apparatus for producing laser pulses at two wavelengths alternately by switching the oscillations of a distributed feedback semiconductor laser of the continuous grating type back and forth across the stop band. The necessary shaping of the gain or index of refraction characteristic along the path of the oscillations is accomplished in part by two top electrodes, one of which is longer than the other along that path, and by varying the current supplied to at least one of those electrodes in the appropriate sense. Applications for optical communication and for optical logic are disclosed, the preferred embodiment being a transmitter for an optical communication system with minimal chirp of the optical pulses, in which pulses at one of the wavelengths are modulated at a bit rate exceeding 1 Gigabit by direct-modulation control of the switching of the laser, and the pulses at the other of the two wavelengths are discarded.

Abstract: In text-to-speech generating arrangements, text is analyzed to determine the language source of words therein by successively selecting letter sequences of each word in the text. At least one signal representative of the probability that the text word corresponds to a particular language source is generated responsive to the selected letter sequences and a language source is selected for converting the text work to a phonetic string responsive to the probability representative signals.

Abstract: There is disclosed an optical ranging system adapted for use with widely varying return signal levels. Automatic signal level control is achieved in two parts, a passive optical part and an active electronic AGC part. The optical part is based on the coaxial arrangement of transmitting and receiving elements in which the shielded transmitting element is mounted in front of the receiving element, which includes Fresnel lens which comprises a plastic casting. The electronic AGC portion of the system includes means for providing a voltage drive (with low internal impedance) for the final AGC transistor when it would tend to be slow, so little phase shift in the control results from changes in the signal levels. Thereby, the determination of distance (the ranging) by phase shift measurement is kept reliable as signal level changes.

Abstract: An arrangement for processing a speech message which uses arbitrary value codes to form time frame excitation signals. The arbitrary value codes, e.g., random numbers, are stored as well as signals indexing the codes and transform domain signals corresponding to the arbitrary codes are generated. The speech message is partitioned into time frame interval speech patterns and a first signal representative of the transform domain speech pattern of each successive time frame interval is formed responsive to the partitioned speech message. A plurality of second signals representative of time frame interval patterns corresponding to the transform code signals are generated responsive to said set of transform signals. One of the arbitrary code signals is selected jointly responsive to the first and second signals of each successive time interval to represent the time frame speech signal excitation, and the index signal corresponding to said selected arbitrary code signal is output.