Patents Examined by Robert L. Griffin
  • Patent number: 4910506
    Abstract: A data communication apparatus comprises means for registering a destination station identification code number, means for storing information, and control means for setting a communication mode by the destination station identification code registration means and the information storing means.
    Type: Grant
    Filed: February 17, 1988
    Date of Patent: March 20, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takehiro Yoshida, Yasuhiro Murayama
  • Patent number: 4910791
    Abstract: A method for calibrating a remote pilot unit is provided wherein both the pilot receiver and the pilot transmitter are calibrated. A test signal of a known magnitude is applied to the pilot unit and the magnitude actually received by the pilot receiver is determined. The two magnitudes are compared and a correction signal is determined. To calibrate the remote transmitter, a signal of a nominal magnitude from the transmitter is applied to a measurement device and the determination is made by the measurement device of the actual magnitude applied. The actual magnitude and the nominal magnitude are compared and a transmitter correction signal is determined. The receiver correction signal and the transmitter correction signal are stored in permanent memory within the pilot unit. This process is repeated at a plurality of frequencies to provide a signature for both the transmitter and the receiver.
    Type: Grant
    Filed: April 14, 1988
    Date of Patent: March 20, 1990
    Assignee: AM Communications, Inc.
    Inventors: Robert V. C. Dickinson, Joseph Rocci, Michael Quelly
  • Patent number: 4910437
    Abstract: A high-pressure discharge lamp comprising a discharge vessel provided with an external auxiliary electrode connected to a starter circuit in the lamp. The starter circuit comprises a voltage division circuit between the connection terminals of the lamp and parallel to the discharge path. A switching element of the starter circuit shunts the voltage division circuit in part and is electrically connected to a control electrode of a semiconductor switch, connected in series with the discharge path and in parallel with the voltage division circuit. As a result a starter circuit and a lamp current limiting circuit are thus combined in the lamp.
    Type: Grant
    Filed: October 31, 1985
    Date of Patent: March 20, 1990
    Assignee: U.S. Philips Corporation
    Inventor: Johny A. J. Daniels
  • Patent number: 4910794
    Abstract: In an exemplary embodiment, a test pattern is sent by a base station at a suitable point in a communications protocol. According to the evaluation of the test pattern transmission, a relatively high data rate or a lower more conservative data rate is selected for the transmission of a relatively lengthy data message. In the most general case, the test pattern can comprise a query from a mobile unit having a message to send, and such test pattern can be transmitted at the lower data rate where its transmission characteristics (e.g. signal strength, jitter or quality of transmission of known information) can be used to predict probable feasibility of transmission at the higher data rate.
    Type: Grant
    Filed: August 4, 1988
    Date of Patent: March 20, 1990
    Assignee: Norand Corporation
    Inventor: Ronald L. Mahany
  • Patent number: 4910793
    Abstract: Information is transmitted at microwave frequencies, the ground station being connected to a waveguide (25) and the station aboard a railway vehicle being connected to an antenna (26). Each station comprises a microwave generator (19) supplying a carrier, transmitters (3 through 7) supplying subcarriers, receivers (28 through 32) and a pilot generator (1). The carrier and subcarrier frequencies are multiples of the pilot frequency and the frequency difference between adjacent subcarriers equals the pilot frequency. A transmitter mixer (MTX) receives the carrier and the subcarriers and is connected to a circulator (24), itself linked to the waveguide (25) in the ground station and to the vehicle station antenna. A receiver mixer (MRX) is connected via a filter (23) to the circulator (24) and receives the carrier from the microwave generator; the latter mixer is connected to the receivers (28 through 32) to which it sends the subcarriers transmitted by the other station.
    Type: Grant
    Filed: December 8, 1987
    Date of Patent: March 20, 1990
    Assignee: Alsthom
    Inventor: Jacques Mainardi
  • Patent number: 4910755
    Abstract: In a bit-serial type data transmission system using the interruption of clock pulses in the timing message to identify separate data word groups in the data messages, a method and apparatus for recovering the transmitter clock oscillator frequency and thereby identifying the interruption interval. The method and apparatus in addition provide signals which may be employed to control the reception of the serial data word groups, to indicate the availability of the data groups as bit-parallel words, and to provide for the retransmission of the received data word groups or the transmission of other word groups.
    Type: Grant
    Filed: February 14, 1989
    Date of Patent: March 20, 1990
    Inventor: Stephen L. Knapp
  • Patent number: 4910730
    Abstract: A Batcher-banyan network which may be implemented using only two different IC chip designs is disclosed. The chips comprising the Batcher banyan network are arranged in adjacent horizontal and vertical stacks to minimize the lengths of electrical conductors connecting the chips.
    Type: Grant
    Filed: March 14, 1988
    Date of Patent: March 20, 1990
    Assignee: Bell Communications Research, Inc.
    Inventors: Chester M. Day, Jr., James N. Giacopelli
  • Patent number: 4910752
    Abstract: A low power digital receiver (10) is provided that contemporaneously selects the lowest possible sampling signal frequency (34) (from a plurality of available sampling signals), and received signal level (28) to properly digitize (32) and recover a desired signal. Digitization is performed after the first IF using broadband stages (28, 30, and 32) that are temporarily enabled (44) to rapidly digitize the first IF signal. This, together with the low sampling rate, minimizes the power consumption of the receiver (10) thereby permitting portable and mobile digital receiver embodiments.
    Type: Grant
    Filed: February 29, 1988
    Date of Patent: March 20, 1990
    Assignee: Motorola, Inc.
    Inventors: Francis R. Yester, Jr., William J. Turney, Paul H. Gailus
  • Patent number: 4910727
    Abstract: An optical transceiver module is disclosed, particularly for connection to a bidirectional optical-waveguide communications network. It contains an optical transmitter (S), an optical receiver (E), and wavelength-selective means (K, C) which prevent any optical feedback to the optical transmitter (S) and the optical receiver (E) and guide the light to be received exclusively to the optical receiver (E). Such means are, for example, wave-length-selective couplers (C, K) implemented as fiber-optic couplers or as one or more integrated optical devices.
    Type: Grant
    Filed: February 2, 1987
    Date of Patent: March 20, 1990
    Assignee: Alcatel N.V.
    Inventor: Kurt Fussganger
  • Patent number: 4908841
    Abstract: A data decoding circuit which receives an input signal comprising a sequence of pulses and generates a digital data output signal and timing signals in response thereto. The circuit includes a phase-locked loop which generates timing signals in response to the input signal and an offset signal from a data separator circuit. The data separator circuit generates the digital data output signal and the offset signal, which measures the degree of correlation between the input signal as received by the data separator and the timing signal from the phase-locked loop, thereby obviating the need to match the data separator circuit closely to the phase-locked loop.
    Type: Grant
    Filed: October 30, 1987
    Date of Patent: March 13, 1990
    Assignee: Digital Equipment Corporation
    Inventors: Michael Leis, Michael J. Muchnik, Elmer Simmons, Russell Brown, Bernardo Rub
  • Patent number: 4908550
    Abstract: Cathode ray tube apparatus including compensation (14) for the vertical component of terrestrial and of other ambient magnetic fields (15). The compensation is achieved by the generation of an opposing vertical magnetic field by energization of the degauss coil (11, 12) in the apparatus. Two embodiments are described: one applies a continuous direct current (21) after the degaussing operation and the other applies a direct current component coincident with the degaussing signal to permanently magnetize components of the apparatus. The magnitude and polarity of the compensation provided may be variable.
    Type: Grant
    Filed: October 27, 1987
    Date of Patent: March 13, 1990
    Inventors: Elaine Chase, Adrian M. Clitheroe, Edward T. Shepherd, Peter Beanlands
  • Patent number: 4908825
    Abstract: A specialized tone receiver is capable of detecting tones on many different digital signal channels simultaneously. A single memory is used to buffer incoming digital signals. Independent write and read sequencers write samples into and read samples from the buffer memory, respectively. The write sequencer writes all samples corresponding to a given sample time at essentially the same time, while the read sequencer reads out all of the samples corresponding to a given channel of interest in reverse sequential chronological order (i.e., in the opposite order from the order the samples were written) beginning with the most current sample. A priority structure controls access to the buffer memory, with the read sequencer being granted a higher access priority than the write sequencer.
    Type: Grant
    Filed: April 8, 1988
    Date of Patent: March 13, 1990
    Assignee: Northern Telecom Limited
    Inventor: Matthew J. J. Vea
  • Patent number: 4908824
    Abstract: A ring-shaped network (RN) which is an offering network is inserted into a subscriber line region of a switching equipment (VE). A gate (GWE) is arranged in one (AEI) of the acceptance devices of the respectively accepting n subscriber line equipment (SLM) and signalling and message transmission procedure matching is done in the gateway means. The coupling to the ring-shaped network (RN) occurs through a ring-coupling (RCB) to which a gateway apparatus (GWE) and an external acceptance device (AEE) which contains a matching device (APE) and a plurality of subscriber line equipment (SLM) are connected. The matching device (APE) provides the signalling and information transmission procedure matching. For example, ISDN subscriber equipment (SE) are connected to the subscriber line equipment (SLM) via central office lines (ASL).
    Type: Grant
    Filed: August 11, 1988
    Date of Patent: March 13, 1990
    Assignee: Siemens Aktiengesellschaft
    Inventors: Gerhard Leibe, Klaus Kuhlmann, Albert Weiss
  • Patent number: 4908840
    Abstract: In a modulation circuit, a variable frequency carrier is modulated by a binary PSK (phase shift keying) modulator with the digital signal of a selected data channel. A plurality of error correction values are stored in storage locations of a memory corresponding to the channels, each of the error correction values being representative of a deviation of the inherent operating characteristic of the modulator when operating at a particular frequency of the carrier from a predetermined operating characteristic. The carrier is generated by a channel synthesizer and its frequency is varied corresponding to the selected channel. The memory is addressed to read an error correction value from one of the storage locations corresponding to the selected channel. An error correction circuit is provided to correct the deviation in response to the error correction value read out of the memory.
    Type: Grant
    Filed: November 21, 1988
    Date of Patent: March 13, 1990
    Assignee: NEC Corporation
    Inventor: Kazuo Kakimoto
  • Patent number: 4907219
    Abstract: A duplex communication wireless apparatus of the type wherein the sum or difference component of a transmission frequency f1 and a reception frequency f2 becomes an intermediate frequency of a receiver. The apparatus includes an input/output resonance circuit exhibiting resonance substantially with said transmission frequency f1 and said reception frequency f2; and a reception input circuit adapted to receive simultaneously both a transmission signal at the transmission frequency f1 from a transmitter and a reception signal at the reception frequency f2 supplied through said input/output resonance circuit for conversion into an intermediate frequency component signal of .vertline.f1.+-.52.vertline. and to produce an output.
    Type: Grant
    Filed: July 20, 1988
    Date of Patent: March 6, 1990
    Assignee: Kabushiki Kaisha Gakushu Kenyusha
    Inventor: Kazutoshi Akao
  • Patent number: 4907291
    Abstract: A miniature microwave transmitter/receiver is small enough to be mounted in the feeder of a microwave antenna. The transmitter and receiver do not interfere with each other despite their close proximity resulting from their small size. The non-interfering results are achieved by frequency separating the bands used for transmission, reception, and the intermediate transmit and receive frequencies. Since none of these frequencies overlap, they do not interfere with each other, even if there is an insufficient isolation between systems.
    Type: Grant
    Filed: May 19, 1987
    Date of Patent: March 6, 1990
    Assignee: NEC Corporation
    Inventor: Osamu Yamamoto
  • Patent number: 4907221
    Abstract: A method of attenuating the echo signal in so-called telephone fork converting circuits, adapted for telephone conferences with a plurality of participants, consists of switching and arranging sequentially on a serial line messages from each participant as coded in the PCM code, by means of a digital switching array, and of performing a sign reversal on the PCM codings of a number of messages equal to the approximation to the nearest number below the number of participants in the conference divided by two.
    Type: Grant
    Filed: May 10, 1988
    Date of Patent: March 6, 1990
    Assignee: SGS-Thomson Microelectronics S.r.L.
    Inventors: Angelo Pariani, Francesco Natali
  • Patent number: 4907248
    Abstract: The system provides correction for error signals caused by noise in the transmission channel in digital signals or analog signals which have been digitized. The first or second differential of the quantized values is taken and encoded. One or more reliable update signals per data block are included in the transmitted signal. Using any difference between an update signal value and the corresponding actual received signal value, an error signal in time reverse sequence is reconstructed in the receiver. This signal is reversed and subtracted from a signal containing the error signal to produce an accurate output signal.
    Type: Grant
    Filed: September 22, 1987
    Date of Patent: March 6, 1990
    Assignee: Zenith Electronics Corporation
    Inventor: Wayne E. Bretl
  • Patent number: 4907292
    Abstract: A television tuner for three frequency ranges (I, II, III) comprises a common antenna connection (4) for corresponding input filter circuits. The input filter circuits (1, 2, 3) of the two higher frequency ranges can be connected to and disconnected from the antenna connection by means of switches (11, 12). The switches (11, 12) are each located between the antenna connection (4) and the associated input filter circuit (2, 3). To improve matching of the input filter circuit (3) and to simplify the configuration of the circuit, the antenna connection (4) is arranged in the proximity of an input filter circuit (1, 2) of the two lower-frequency frequency ranges (I, II). In addition, the switch (12) for the highest frequency range (III) is connected to the end of a coupling conductor (5) which is spaced closest to the antenna connection (4).
    Type: Grant
    Filed: October 1, 1987
    Date of Patent: March 6, 1990
    Assignee: Telefunken Electronic GmbH
    Inventor: Emil Leipert
  • Patent number: 4904897
    Abstract: An oxide cathode comprising a base 1 which consists substantially of titanium and a heater element 5 coated with aluminium oxide 6 to heat the base 1, which bears a porous alkaline earth metal oxide emissive layer 4. When the surface of the titanium base 1 which is opposed to the heater element 5 bears a metal layer 7 consisting at least of one of the metals Pt, Mo, Ta and W, a solution is obtained to the problem occurring in titanium cathodes in that titanium in contact with aluminium oxide is not chemically stable. The metal layer preferably consisits of pure tungsten and is formed by chemical vapour desposition (CVD). The metal layer is preferably from 1 to 10 .mu.m thick.
    Type: Grant
    Filed: December 4, 1984
    Date of Patent: February 27, 1990
    Assignee: U.S. Philips Corporation
    Inventors: Johannes Van Esdonk, Jan Hasker, Jacobus Stoffels