Patents by Inventor Toshiaki Fujikura

Toshiaki Fujikura has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7684831
    Abstract: A signal processing device includes: a speaker amplifier for amplifying a reception voice; a reception voice attenuator for attenuating the reception voice inputted to the speaker amplifier during a voice transmission mode; a reception voice detection circuit for detecting the reception voice outputted from the speaker amplifier; a microphone amplifier for amplifying a transmission voice inputted to a microphone; a transmission voice attenuator for attenuating the transmission voice outputted by the microphone amplifier during a voice reception mode; a transmission voice detection circuit for detecting the transmission voice outputted by the microphone amplifier; and a discriminator for discriminating the mode to be operated among the voice transmission mode and the voice reception mode on the basis of detection outputs from the reception voice detection circuit and the transmission voice detection circuit.
    Type: Grant
    Filed: August 22, 2007
    Date of Patent: March 23, 2010
    Assignee: Uniden Corporation
    Inventor: Toshiaki Fujikura
  • Publication number: 20090011800
    Abstract: A signal processing device includes: a speaker amplifier for amplifying a reception voice; a reception voice attenuator for attenuating the reception voice inputted to the speaker amplifier during a voice transmission mode; a reception voice detection circuit for detecting the reception voice outputted from the speaker amplifier; a microphone amplifier for amplifying a transmission voice inputted to a microphone; a transmission voice attenuator for attenuating the transmission voice outputted by the microphone amplifier during a voice reception mode; a transmission voice detection circuit for detecting the transmission voice outputted by the microphone amplifier; and a discriminator for discriminating the mode to be operated among the voice transmission mode and the voice reception mode on the basis of detection outputs from the reception voice detection circuit and the transmission voice detection circuit.
    Type: Application
    Filed: August 22, 2007
    Publication date: January 8, 2009
    Applicant: UNIDEN CORPORATION
    Inventor: Toshiaki Fujikura
  • Publication number: 20080122405
    Abstract: A filter for smoothing pulse voltage outputted by a transistor has a diode, an inductance, a resistor element and a capacitor. The resistor element is functionally homologous to the equivalent series resistance of the capacitor. A capacitor having a low equivalent series resistance can be used as the capacitor by virtue of employing as the resistor element a resistor having a resistance value such that the control circuit is supplied with the necessary and sufficient feedback signals for a stable operation of a feedback system. Reducing the equivalent series resistance of the capacitor allows suppressing generation of ripple voltage inputted to the battery, making it possible to realize stable charge control.
    Type: Application
    Filed: February 27, 2007
    Publication date: May 29, 2008
    Inventor: Toshiaki Fujikura
  • Patent number: 6907094
    Abstract: The present invention provides a diversity receiving device with superior interference resistance in a simple construction, comprising a plurality of antennas (11, 12); an antenna switching device (13) that selects any one of a plurality of antennas (11, 12) and carries out connection switching thereof; a demodulator (14) that demodulates a wireless signal and obtains a baseband spread spectrum signal; an A/D converter (15) that A/D converts the baseband spread spectrum signal and generates chip data; a digital matched filter (16) that finds the correlation value of the chip data and the spreading code; a maximum correlation value detection portion (18) that detects the maximum correlation value; an average value calculation portion (21) that finds the average value per frame of the maximum correlation value; and a level comparison device (22) that compares the above-mentioned average value and a predetermined threshold value, and outputs a control signal to the antenna switching device (13) to control antenn
    Type: Grant
    Filed: March 12, 2002
    Date of Patent: June 14, 2005
    Assignee: Uniden Corporation
    Inventors: Masaki Matsui, Shigeo Sato, Toshiaki Fujikura, Akio Horibe, Muneki Ito
  • Patent number: 6839550
    Abstract: An optimum antenna is readily selected from three or more antennas, by means of an existing device which is only capable of switching between two antennas. The device of the invention comprises: a switching device for receiving signals from two antennas as a pair of antenna selected from three or more antennas, and outputting the first signal (DATADET) indicating that receiving is in progress, and the second signal (ANTSEL) indicating which antenna being used for receiving; a judgement circuit for judging which antenna is suitable for receiving and actually being used in the said pair of antenna, on the basis of the said first and the said second signal of the said switching device; a setting circuit for resetting said pair of antenna on the basis of the output of said judgement circuit; and a switching circuit for selecting two antennas which is set by the said setting circuit as a pair and supplying the output thereof to the said switching device.
    Type: Grant
    Filed: April 17, 2002
    Date of Patent: January 4, 2005
    Assignee: Uniden Corporation
    Inventors: Takayuki Iguchi, Akio Horibe, Toshiaki Fujikura
  • Publication number: 20040203373
    Abstract: Provided is a wireless terminal device and a communications system that is able to maximize the effect of expanding the communication availability range by interposing a virtual base station. The wireless terminal device of this invention is used in a communications system where one terminal in a group of terminals becomes a master station, and the remaining terminals become slave stations. The wireless terminal device with switchable operation modes comprises at least: a standby mode for performing communications within the group and obtaining information regarding a terminal that is able to communicate with its own terminal; a master station mode; and a slave station mode.
    Type: Application
    Filed: October 25, 2002
    Publication date: October 14, 2004
    Inventors: Minoru Ogino, Toshiaki Fujikura, Katsunori Yamamoto
  • Publication number: 20040203936
    Abstract: It is the objective of the present invention to realize a highly flexible communication system, in which a communication terminal can freely change from master station operating mode to slave station operating mode or vice versa at its own spontaneous request. In order to achieve this objective, a communication terminal of the present invention, by switching from one mode to the other, operates in either master station operating mode for communicating with a plurality of slave stations that constitute a communication system, and also for controlling the communication system, or slave station operating mode for operating as a slave station in response to a control message from a master station. When terminal 2 operating in slave station operating mode needs to operate as the master station, terminal 2 informs terminal 5, which is the master station, of a transition request REQ 1, for making the transition to the master station.
    Type: Application
    Filed: October 21, 2002
    Publication date: October 14, 2004
    Inventors: Minoru Ogino, Yukihiro Yamada, Katsunori Yamamoto, Toshiaki Fujikura
  • Publication number: 20040018848
    Abstract: Provided is a technique to execute stable one-to-N calls in a distributed system without a base station, by solving problems such as overhead due to the switching of the transmission terminal, variations in the combinations of terminals that can communicate with one another, and transmission collisions. The wireless terminal device of this invention operates either as a master station for transmitting data during a first time slot and receiving data during a second time slot, or as a slave station for transmitting data during the second time slot and receiving data during the first time slot. When the wireless terminal device of this invention operates as the master station, it comprises: a first unit for transmitting data input at its own terminal to another terminal; a second unit for, upon receiving data input at another terminal, transmitting the data to another terminal; and a switching unit to exclusively work the first and second units.
    Type: Application
    Filed: October 25, 2002
    Publication date: January 29, 2004
    Inventors: Minoru Ogino, Toshiaki Fujikura, Katsunori Yamamoto
  • Publication number: 20030026366
    Abstract: The present invention provides a diversity receiving device with superior interference resistance in a simple construction, comprising a plurality of antennas (11, 12); an antenna switching device (13) that selects any one of a plurality of antennas (11, 12) and carries out connection switching thereof; a demodulator (14) that demodulates a wireless signal and obtains a baseband spread spectrum signal; an A/D converter (15) that A/D converts the baseband spread spectrum signal and generates chip data; a digital matched filter (16) that finds the correlation value of the chip data and the spreading code; a maximum correlation value detection portion (18) that detects the maximum correlation value; an average value calculation portion (21) that finds the average value per frame of the maximum correlation value; and a level comparison device (22) that compares the above-mentioned average value and a predetermined threshold value, and outputs a control signal to the antenna switching device (13) to control antenn
    Type: Application
    Filed: March 12, 2002
    Publication date: February 6, 2003
    Applicant: Uniden Corporation
    Inventors: Masaki Matsui, Shigeo Sato, Toshiaki Fujikura, Akio Horibe, Muneki Ito
  • Publication number: 20020149517
    Abstract: An optimum antenna is readily selected from three or more antennas, by means of an existing device which is only capable of switching between two antennas. The device of the invention comprises: a switching device for receiving signals from two antennas as a pair of antenna selected from three or more antennas, and outputting the first signal (DATADET) indicating that receiving is in progress, and the second signal (ANTSEL) indicating which antenna being used for receiving; a judgement circuit for judging which antenna is suitable for receiving and actually being used in the said pair of antenna, on the basis of the said first and the said second signal of the said witching device; a setting circuit for resetting said pair of antenna on the basis of the output of said judgement circuit; and a switching circuit for selecting two antennas which is set by the said setting circuit as a pair and supplying the output thereof to the said switching device.
    Type: Application
    Filed: April 17, 2002
    Publication date: October 17, 2002
    Applicant: UNIDEN CORPORATION
    Inventors: Takayuki Iguchi, Akio Horibe, Toshiaki Fujikura
  • Patent number: 6418209
    Abstract: The present invention has the purpose of realizing an infallible in-call incoming signal notification incoming signal notification service with this erroneous action eliminated to the extent possible.
    Type: Grant
    Filed: August 21, 1998
    Date of Patent: July 9, 2002
    Assignee: Uniden Corporation
    Inventors: Toshiaki Fujikura, Yoichi Harada, Masahito Asa
  • Patent number: 5960358
    Abstract: When an SP key is operated when power from a commercial utility is disconnected, an energized state forming circuit forms an energized state from a subscriber's line and power is supplied from the subscriber's power supply section through the energized state forming circuit to a microcomputer. The microcomputer thus is operated from the subscriber's line even after power failure occurs.
    Type: Grant
    Filed: March 6, 1997
    Date of Patent: September 28, 1999
    Assignee: Uniden Corporation
    Inventors: Toshiaki Fujikura, Daisuke Nakamura
  • Patent number: 5929598
    Abstract: Capacitors are connected in parallel to a primary side induction coil in a charger 1 and a secondary side induction coil in a cordless equipment (handset unit) respectively, and LC parallel resonance circuits are formed in the charger and the cordless equipment respectively with this parallel connection. Each of the primary side induction coil and secondary side induction coil is formed with a sheet coil, and the sheet coils are arranged and fixed in the charger and the cordless equipment respectively so that the sheet coils face to each other with a prespecified gap in the charging state where the cordless equipment has been set in the charger.
    Type: Grant
    Filed: July 3, 1997
    Date of Patent: July 27, 1999
    Assignee: Uniden Corporation
    Inventors: Hidekazu Nakama, Toshiaki Fujikura, Akitsugu Shigino
  • Patent number: 5825161
    Abstract: When a reference potential is loaded to a pair of lead wires connected via a resistor having a resistance value corresponding to a specified battery capacity, a partial potential is obtained through a serial circuit comprising the resistor above, a diode, and another resistor, and a collector current for transistors is adjusted according to a relation between the partial potential and the resistor. As a result, a current value of the charging current supplied from a charger to a battery pack is controlled, and a charging operation for a charging time allocated by a microcomputer to standard charging or fast charging is insured.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: October 20, 1998
    Assignee: Uniden Corporation
    Inventors: Toshiaki Fujikura, Hidekazu Nakama
  • Patent number: 5481595
    Abstract: A portable telephone is disclosed which comprises a data memory having a plurality of data storage locations for storing telephone numbers used to initiate telephone calls as an auto-dialer function. An audio memory is also disclosed which comprises a plurality of audio storage location, each of which may be linked to one of the data storage locations. A controller with a key matrix for inputting commands and a display for displaying status is included such that commands can be entered that cause the controller to sequentially recall telephone numbers stored in the data memory and play back voice tags stored in the audio memory, that are linked with the data memory. A loud speaker is disclosed for playing back the audio tags at a loud volume. When a tag is heard that represents the desired call destination, that call is initiated.
    Type: Grant
    Filed: March 8, 1994
    Date of Patent: January 2, 1996
    Assignees: Uniden America Corp., Uniden Corporation
    Inventors: Susumu Ohashi, Hideo Tateishi, Toshiaki Fujikura
  • Patent number: 5381460
    Abstract: A portable cellular telephone having a loud speaker for implementing a monitor mode function which operates separately from the normal head set mode of operation and further has a default mode selector which varies the monitor mode function depending on whether a call is being initiated or received. The portable cellular telephone further has a display for displaying the current mode of the monitor mode function.
    Type: Grant
    Filed: December 30, 1993
    Date of Patent: January 10, 1995
    Assignees: Uniden America Corp.,, Uniden Corporation
    Inventors: Susumu Ohashi, Hideo Tateishi, Toshiaki Fujikura