Patents Examined by Ralph E. Smith
  • Patent number: 5107521
    Abstract: A method and system is disclosed which provides a multi-data rate demodulator for a communication system. The present invention 10 demodulates and extracts a data signal from a received analog signal. A baseband signal is extracted by filtering and downconverting the received analog signal. The baseband signal is sampled and converted to a digital signal, providing a digital word corresponding to each sample. A digital filter provides a sum of the digitized samples over a programmable symbol time corresponding to the signal data rate. The data signal is then extracted by processing the sums of the digitized samples.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: April 21, 1992
    Assignee: Hughes Aircraft Company
    Inventor: Douglas T. Bell
  • Patent number: 5103465
    Abstract: An improved symbol synchronization circuit is provided for generting a clock signal in a receiver having an input signal comprising a stream of symbols at a symbol rate of f.sub.symbol. According to the invention, a correlator is provided that operates on a multiplicity (k) of multi-phase signals, .phi..sub.1 -.phi..sub.k, each signal more or less synchronized with the stream of symbols and each having a frequency f.sub.clock generally equal to a multiple of f.sub.symbol. Based on the current synchronization of each signal .phi..sub.1 -.phi..sub.k with the stream of symbols, and also based on the past history of the synchronization of each signal with the stream of symbols, one member from the group of signals .phi..sub.1 -.phi..sub.k is periodically selected as the clock signal. This selected clock signal is then delayed to compensate for the drift between f.sub.symbol and f.sub.clock.
    Type: Grant
    Filed: August 25, 1989
    Date of Patent: April 7, 1992
    Assignee: Motorola, Inc.
    Inventors: Kenneth J. Crisler, Mark J. Marsan
  • Patent number: 5046074
    Abstract: The invention enables extremely quick and reliable recovery of the synchronization of a communication signal transmitted in a half-duplex link. Such a communication signal comprises first time intervals including useful data, and second time intervals devoid of useful data and in a given logic state. At the beginning of each of the first time intervals is included a digital synchronization pattern which is then considered as associated with the second time intervals to form synchronization words of great length. The synchronization of the communication signal is recovered by detecting the synchronization words of great length in the communication signal.
    Type: Grant
    Filed: August 16, 1989
    Date of Patent: September 3, 1991
    Assignee: L'Etat Francais represente par le Ministre des Postes, des Telecommunications et de l'Espace (Centre d'Etudes des Telecommunications)
    Inventors: Jacques Abiven, Gilles Ramel
  • Patent number: 5043999
    Abstract: Circuit arrangement for digitally setting the gain factor of a digitally adjustable receive amplifier. For digitally setting the gain factor of a digitally adjustable receive amplifier independently of the reception signal, the circuit arrangement for positive and negative reception signals amplified by the gain factor has comparators whose outputs are fed back via respective feedback switching network to a comparison input of the respective appertaining comparator. As a result of the feedback switching networks the signal level at each of the comparison inputs has different comparison values which are dependent on the signal levels at the output of the respective comparator. Whenever the signal level of the reception signal exceeds one of the comparison values, a counter, that may be a non-linear counter, is decremented by one step and thereby provides a counter reading indicating the gain.
    Type: Grant
    Filed: February 21, 1990
    Date of Patent: August 27, 1991
    Assignee: Siemens Aktiengesellschaft
    Inventors: Michael Aimer, Karl Besemer
  • Patent number: 5043719
    Abstract: A matrix circuit has a plurality of blocks each including a plurality of semiconductor unit elements, the semiconductor unit elements of each block being adapted to be impressed with a predetermined voltage at the same time, each unit element becoming active when impressed with the predetermined voltage, and a drive device for impressing the predetermined voltage to the plurality of blocks sequentially. The matrix circuit includes a first selective device for selecting either ground or a desired other than ground voltage, and a second selective device for selecting one of the output of the drive device and the output of the first selective device whereby the output of the second selective device renders active the plurality of unit elements of each block.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: August 27, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsumi Nakagawa, Toshiyuki Komatsu, Shinichi Seito, Yasuo Kuroda, Katsunori Hatanaka
  • Patent number: 5008661
    Abstract: An electronic remote chemical identification system is described, in which a transponder for recording information regarding the contents and other information of a railroad tank car, highway tank truck or other container is placed thereon, the transponder being coded remotely with the information by a remotely located, fixed or portable encoder and interrogated when desired by a remotely located, fixed or portable interrogator unit. In the case of an accident, emergency and other response personnel can utilize the interrogator to query a single or a plurality of transponders on the tank cars in the train or on the tank truck to safely and immediately ascertain the exact contents of the containers and other associated information regarding the shipper, the origin and destination of the consignment, shipper's emergency personnel telephone number and proper response action to be taken at the accident scene, etc.
    Type: Grant
    Filed: January 4, 1989
    Date of Patent: April 16, 1991
    Inventor: Phani K. Raj
  • Patent number: 4991227
    Abstract: The period of time that the squelch circuit maintains a radio receiver's audio amplifier active after the signal strength of a received carrier fades below a threshold level is inversely proportional to the strength of the received carrier immediately before the fade. This threshold level is also variable. If, immediately before the fade, the received signal strength exceeds a predetermined trigger level (Vtrg) the threshold level is raised. A buffer amplifier (102) charges a capacitor (C) to a voltage which is proportional to the strength of a received carrier. If the carrier fades below a threshold (Vth2 or Vth3, the buffer is disabled and the capacitor slowly discharges through a resistor (R). When the voltage at the capacitor crosses a reference voltage (Vref1) the output of a comparator (104) switches, thereby deactivating the receiver's audio amplifier.
    Type: Grant
    Filed: January 11, 1988
    Date of Patent: February 5, 1991
    Assignee: Motorola, Inc.
    Inventor: Walter H. Kehler, Jr.
  • Patent number: 4949084
    Abstract: An interconnection device in the form of a programmable integrated crosspoint switch includes a matrix of first and second pluralities of electrically conductive paths, e.g. an M line by N line matrix, and selectively permanently and affirmatively programmable switch elements for completing passive conductive circuit paths between one or more of the conductive paths of such first and second pluralities thereof. The programmable integrated crosspoint switch invention may be utilized in various hierarchical levels of interconnection.
    Type: Grant
    Filed: October 17, 1988
    Date of Patent: August 14, 1990
    Assignee: Ohio Associated Enterprises, Inc.
    Inventors: Rod Schwartz, John T. Venaleck, Kenneth W. Braund
  • Patent number: 4939785
    Abstract: In a radio communication network system for use in carrying out communication with a plurality of radio telephone sets in a service zone by the use of a control channel and a plurality of speech channels, a connecting equipment unit (CE) is selectively operable in cooperation with a radio control unit (RCU) in a speech mode of forming a speech path through a selected one of the speech channels and an additional mode of selectively monitoring the control and the speech channels. The additional mode may be divided into first and second control modes for allowing and rejecting reception of a call with the control channel monitored, respectively. Alternatively, either a rest mode or a combination of rest and initial program loading modes may be added to the additional mode. A plurality of the connecting equipment units may be located in a single service zone and selectively put into the speech and the additional modes with only one of the connecting equipment units kept in the first control mode.
    Type: Grant
    Filed: May 31, 1988
    Date of Patent: July 3, 1990
    Assignees: Nippon Telegraph and Telephone Corp., Matsushita Communication Industrial Co., Ltd., NEC Corp.
    Inventors: Yoshitoshi Murata, Masahiko Hirono, Toshihiko Shibata, Fumio Suzuki, Mitsuo Sato, Tadao Hashimoto
  • Patent number: 4939788
    Abstract: An FM receiver capable of generating a signal showing the electric field intensity of a received signal. More particularly, an FM receiver capable of generating a signal showing the electric field, wherein the dynamic range is expanded, and the linearity is improved. The enlargement of the dynamic range of the signal showing the electric field intensity may be effected, and also the linearity may be improved. Accordingly, the electric field intensity of the received signal may be correctly displayed by a display, etc. Especially, as the gain control is effected through the control of the operation current of the gain control amplification circuit in accordance with the gain control signal by the differential type of level detection circuit, an FM receiver suitable for IC may be provided.
    Type: Grant
    Filed: February 9, 1989
    Date of Patent: July 3, 1990
    Assignee: Sanyo Electric Co., Ltd.
    Inventor: Hiroki Hasegawa
  • Patent number: 4935734
    Abstract: Configurable semiconductor integrated circuits as-made each have a plurality of logic circuits formed at discrete sites. For each logic circuit, direct selectably conducting/non-conducting connection paths extend from its output to input of a first set of other logic circuits and to its inputs from outputs of a second set of other logic circuits. All of the sets for all of the logic circuits are each different. Other direct connection paths are selectably connectable to inputs and outputs of the logic circuits. Selection can be irreversible or reversible and involves coincident signal addressing of the sites and coded configuring of the paths at that site. Reversible selection can be via field effect transistors or bipolar transistors and can be at or near normal logic signal levels and speeds. Versatile configurable input/output arrangements are described also reconfigurable data processing systems using the reversible transistor provisions.
    Type: Grant
    Filed: September 10, 1986
    Date of Patent: June 19, 1990
    Assignee: Pilkington Micro-Electronics Limited
    Inventor: Kenneth Austin
  • Patent number: 4926495
    Abstract: A computer aided dispatch system is provided for use in a trunked communication system. The system comprises at least a master file node and a plurality of user nodes. The master file node contains a data record for each subscriber on the trunked communication system. Each data record has a plurality of fields that may assume various values. Each dispatcher "attaches" to a particular value of at least one field in any of the data records. The master file node maintains the records for each subscriber and automatically transmits an updated record to each dispatcher attached to the subgroup in which the subscriber operates. In this way, dispatchers are continuously provided the latest subscriber status even though the responsibility for monitoring the status of a particular subscriber unit may dynamically pass from dispatcher to dispatcher.
    Type: Grant
    Filed: December 11, 1986
    Date of Patent: May 15, 1990
    Assignee: Motorola, Inc.
    Inventors: Richard A. Comroe, Richare H. Coe, Katherine B. Roane, Lewis H. Rosenthal
  • Patent number: 4918440
    Abstract: Programmable logic cells, and arrays of those cells, having certain characteristics, including: (1) the ability to program each cell to act either as a logic element or as a logical identity element(s) between one or more inputs and one or more outputs; (2) the ability to rotate circuits by 90.degree. and to reflect circuits about horizontal and vertical axes; (3) an integrated logic and communication structure which emphasizes strictly local communications; (4) a minimal complexity of logic functions available at the cell level, making available a very fine-grained logic structure; and (5) suitability for implementation of both synchronous and asynchronous logic, including speed-independent circuits. Cells are arranged in a grid, with each cell communicating with its north, east, west and south neighbors. The cells are programmable to several states.
    Type: Grant
    Filed: November 7, 1986
    Date of Patent: April 17, 1990
    Inventor: Frederick C. Furtek
  • 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: 4910795
    Abstract: A microphone is provided in which two circuit boards are held in spaced parallel position by each being connected at one end to a supporting member and by each resting at the other end in a pair of stabilizing grooves located within the microphone head. A battery holding assembly has attached at one end the supporting member, and at the other end an antenna mounting surface onto which a coiled antenna is placed. A battery holding compartment is located between the supporting member and the antenna so that a battery held in the compartment acts as an addition to the antenna itself. A power and battery level indicator flashes on and off to warn that the charge of the battery is reaching a predetermined low point. The electronic circuitry for the indicator is also provided.
    Type: Grant
    Filed: June 11, 1987
    Date of Patent: March 20, 1990
    Inventors: Clinton R. McCowen, Gerald G. Doiron
  • 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: 4906987
    Abstract: The printed circuit board system and method are characterized by the use of at least one integrated circuit path bridging device, preferably a programmable integrated crosspoint switch, mounted to a printed circuit board for enabling electrical interconnection or circuit paths to cross over other electrical interconnection or circuit paths whereby a single plane or surface interconnection system can be given multi-plane interconnection potential or a multi-plane interconnection system can be given increased interconnection potential, while avoiding or minimizing drawbacks associated with multi-plane circuit interconnection systems such as need for plated through holes and relatively high cost.
    Type: Grant
    Filed: December 15, 1986
    Date of Patent: March 6, 1990
    Assignee: Ohio Associated Enterprises, Inc.
    Inventors: John T. Venaleck, Kenneth W. Braund
  • Patent number: 4896371
    Abstract: A synchronous transmission system that improves reception in areas where the main and the satellite signal create significant self interference. At least one of the synchronous transmitters is phase modulated in accordance with a selected modulation function which varies at a sub sonic rate.
    Type: Grant
    Filed: November 20, 1987
    Date of Patent: January 23, 1990
    Inventor: Leonard R. Kahn
  • Patent number: 4893349
    Abstract: An improved FM communication system is disclosed in which noise bursts and pops in the audio output of the receiver, due to weak and Rayleigh-faded signals, are minimized by selectively attenuating the audio signal in the receiver. The amount and rate of attenuation for the receiver noise reduction circuits is determined by a control signal derived form either the average discriminator noise at frequencies above 3 kHz, or from a received RF signal strength indicator, or a combination of both. The audio output is attenuated during weak signals or Rayleigh fades only when the attenuation control signal increases above a predetermined signal-to-noise ratio threshold. Also described are further improvements to noise attenuation devices used in combination with the receiver noise reduction circuits to enhance audio quality in particular applications, e.g., FM repeater systems which may incorporate multiple transmitters in a simulcast configuration.
    Type: Grant
    Filed: August 28, 1987
    Date of Patent: January 9, 1990
    Assignee: Motorola, Inc.
    Inventors: Bruce C. Eastmond, Wai Elliott Lum
  • Patent number: RE33808
    Abstract: A signal substitution system for cable television applies substitute television program signals in at least one substitute channel to the transmission cable along with signal substitution control signals. The signal substitution control signals include a plurality of different terminal command signals and a plurality of different event command signals. Each of the terminal command signals includes a respective panelist address signal for identifying a respective panelist receiving station and a plurality of event identification signals identifying respective events. Each of the event command signals includes a respective event address signal corresponding to a respective event and a normal channel identification signal for identifying a normal channel into which a substitute television program is to be switched. A controller at each panelist receiving station responds to the signal substitution control signals by selectively switching a substitute television program into a normal channel.
    Type: Grant
    Filed: August 28, 1985
    Date of Patent: January 28, 1992
    Assignee: Information Resources, Inc.
    Inventor: W. Andrew Wright, Jr.