Patents by Inventor Kazuhiro Arimitsu

Kazuhiro Arimitsu 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: 7809411
    Abstract: In a CDMA mobile terminal, the power supply voltage of the mobile terminal is compared with a first threshold voltage, and frequency monitor is performed at a normal rate if the power supply voltage is higher than the first threshold voltage, and frequency monitor is performed at 1/N of the normal rate if the power supply voltage is lower than the first threshold voltage, where N is equal to or greater than 2. Additionally, the power level of an RF signal received by the mobile terminal is compared with a first reference level, and frequency monitor is performed at the normal rate if the power level of the RF signal is lower than the first reference level, and frequency monitor is performed at 1/N of the normal rate if the power level of the RF signal is higher than the first reference level.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: October 5, 2010
    Assignee: NEC Corporation
    Inventor: Kazuhiro Arimitsu
  • Patent number: 7664521
    Abstract: In the mobile communication system, a total reception quality between a terminal and a base station is converged into a target quality, thereby suppressing a period in which the transmission power of a distant station becomes excessive.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: February 16, 2010
    Assignee: NEC Corporation
    Inventor: Kazuhiro Arimitsu
  • Publication number: 20090017854
    Abstract: [PROBLEMS] To efficiently switch frequencies of communication between a mobile station and a base station. [MEANS FOR SOLVING PROBLEMS] There are included a mobile station (B6) that switches frequencies between base stations (B1-B5) to perform communication; and a base station control apparatus (B7) that controls the base stations and the mobile station (B6). The mobile station (B6) has a level measuring part (A7) that measures the communication quality information, while the base station control apparatus (B7) has a control part (F3) that performs, based on the foregoing quality information, a determination as to the foregoing frequency switching. This determination as to the foregoing frequency switching is performed based on the communication quality information measured by the mobile station (B6) that switches frequencies between the base stations to perform communication.
    Type: Application
    Filed: March 9, 2006
    Publication date: January 15, 2009
    Applicant: NEC CORPORATION
    Inventor: Kazuhiro Arimitsu
  • Publication number: 20070004469
    Abstract: In a CDMA mobile terminal, the power supply voltage of the mobile terminal is compared with a first threshold voltage, and frequency monitor is performed at a normal rate if the power supply voltage is higher than the first threshold voltage, and frequency monitor is performed at 1/N of the normal rate if the power supply voltage is lower than the first threshold voltage, where N is equal to or greater than 2. Additionally, the power level of an RF signal received by the mobile terminal is compared with a first reference level, and frequency monitor is performed at the normal rate if the power level of the RF signal is lower than the first reference level, and frequency monitor is performed at 1/N of the normal rate if the power level of the RF signal is higher than the first reference level.
    Type: Application
    Filed: August 31, 2006
    Publication date: January 4, 2007
    Applicant: NEC Corporation
    Inventor: Kazuhiro Arimitsu
  • Patent number: 7146151
    Abstract: In a CDMA mobile terminal, the power supply voltage of the mobile terminal is compared with a first threshold voltage, and frequency monitor is performed at a normal rate if the power supply voltage is higher than the first threshold voltage, and frequency monitor is performed at 1/N of the normal rate if the power supply voltage is lower than the first threshold voltage, where N is equal to or greater than 2. Additionally, the power level of an RF signal received by the mobile terminal is compared with a first reference level, and frequency monitor is performed at the normal rate if the power level of the RF signal is lower than the first reference level, and frequency monitor is performed at 1/N of the normal rate if the power level of the RF signal is higher than the first reference level.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: December 5, 2006
    Assignee: NEC Corporation
    Inventor: Kazuhiro Arimitsu
  • Patent number: 6957079
    Abstract: In a base station transmission power control method, the first expected value of the first block error rate representing predetermined reception quality is set in a potable terminal apparatus. The second block error rate in the potable terminal apparatus is measured with the second count smaller than the first count which is an execution count of error detection processing required to measure the first block error rate. The potable terminal apparatus controls the transmission power of a base station on the basis of the measured second block error rate. A base station transmission power control apparatus is also disclosed.
    Type: Grant
    Filed: November 8, 2001
    Date of Patent: October 18, 2005
    Assignee: NEC Corporation
    Inventor: Kazuhiro Arimitsu
  • Publication number: 20050197151
    Abstract: In the mobile communication system, a total reception quality between a terminal and a base station is converged into a target quality, thereby suppressing a period in which the transmission power of a distant station becomes excessive.
    Type: Application
    Filed: February 17, 2005
    Publication date: September 8, 2005
    Applicant: NEC Corporation
    Inventor: Kazuhiro Arimitsu
  • Publication number: 20050048930
    Abstract: A portable communication terminal 101 is capable of originating a call based on any one of a plurality of local numbers that can be used upon origination. Previously registered in an address book 112 are each communication counterpart and a specific local number to be selected from the plurality of local numbers upon origination in association with each other. When a call is originated to a given communication counterpart selected by a user, the portable communication terminal 101 refers to the address book 112 to thereby originate a call based on the specific local number associated with the communication counterpart.
    Type: Application
    Filed: August 18, 2004
    Publication date: March 3, 2005
    Inventor: Kazuhiro Arimitsu
  • Publication number: 20040264412
    Abstract: A communication apparatus receives signals from a plurality of sectors, calculates a plurality of kinds of variation patterns for each of the signals from the sectors, and selects a particular sector suitable for connector with reference to a relationship among the sectors in variation patterns as a calculation result. The variation patterns may be an average, a variation amount, and a variation direction.
    Type: Application
    Filed: June 25, 2004
    Publication date: December 30, 2004
    Applicant: NEC Corporation
    Inventor: Kazuhiro Arimitsu
  • Patent number: 6731911
    Abstract: An AFC process is performed even when a mobile station is in a waiting mode in which an incoming call is monitored via a paging channel. Even in the waiting mode, a finger receiver receives a BCCH, and an AFC circuit carries out the AFC process using the BCCH. No reception failure occurs even when a TCXO, i.e., a reference oscillator, suffers frequency fluctuations in the waiting mode.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: May 4, 2004
    Assignee: NEC Corporation
    Inventors: Masaru Hirata, Kazuhiro Arimitsu
  • Patent number: 6693955
    Abstract: A portable terminal has a level detect or which compares profile data generated by a profile generator with a threshold value, and determines a sampling rate for a correlating process performed by a correlator based on the result of the comparison. The sampling rate is determined in order to increase the sampling rate at profile points in excess of the threshold value, of the profile data. Therefore, profile data is generated highly accurately at a higher sampling clock rate at points which require a higher accuracy, and profile data is generated at a lower sampling clock rate at points which do not require such a higher accuracy.
    Type: Grant
    Filed: August 25, 2000
    Date of Patent: February 17, 2004
    Assignee: NEC Corporation
    Inventor: Kazuhiro Arimitsu
  • Patent number: 6625434
    Abstract: An AFC process is performed even when a mobile station is in a speech communication mode in which a data channel is being received by a finger receiver. In the speech communication mode, a frequency error measuring unit measures a frequency error of the data channel. An AFC circuit performs an AFC process for controlling the frequency of a TCXO, i.e., a reference oscillator, using the measured frequency error. No reception failure occurs even when the TCXO suffers frequency fluctuations in the speech communication mode.
    Type: Grant
    Filed: September 29, 1999
    Date of Patent: September 23, 2003
    Assignee: NEC Corporation
    Inventors: Kazuhiro Arimitsu, Masaru Hirata
  • Publication number: 20030123407
    Abstract: A mobile station controls transmission power in accordance with a pattern of a pilot symbol. The mobile station includes a transmission power controller to indicate a transmission power amplifier to change transmission power in response to a pattern of the pilot symbol included in symbol data decoded by a decoder. The TPC symbol to control transmission power becomes therefore unnecessary, and hence the symbol rate can be increased by increasing the logical channel symbols. With three or more pilot symbol patterns, the transmission power control steps are increased to more flexibly control transmission power as compared with the power control operation using one TPC symbol.
    Type: Application
    Filed: September 28, 1999
    Publication date: July 3, 2003
    Inventor: KAZUHIRO ARIMITSU
  • Publication number: 20030104849
    Abstract: In a CDMA mobile terminal, the power supply voltage of the mobile terminal is compared with a first threshold voltage, and frequency monitor is performed at a normal rate if the power supply voltage is higher than the first threshold voltage, and frequency monitor is performed at 1/N of the normal rate if the power supply voltage is lower than the first threshold voltage, where N is equal to or greater than 2. Additionally, the power level of an RF signal received by the mobile terminal is compared with a first reference level, and frequency monitor is performed at the normal rate if the power level of the RF signal is lower than the first reference level, and frequency monitor is performed at 1/N of the normal rate if the power level of the RF signal is higher than the first reference level.
    Type: Application
    Filed: November 27, 2002
    Publication date: June 5, 2003
    Inventor: Kazuhiro Arimitsu
  • Publication number: 20020058524
    Abstract: In a base station transmission power control method, the first expected value of the first block error rate representing predetermined reception quality is set in a potable terminal apparatus. The second block error rate in the potable terminal apparatus is measured with the second count smaller than the first count which is an execution count of error detection processing required to measure the first block error rate. The potable terminal apparatus controls the transmission power of a base station on the basis of the measured second block error rate. A base station transmission power control apparatus is also disclosed.
    Type: Application
    Filed: November 8, 2001
    Publication date: May 16, 2002
    Applicant: NEC CORPORATION
    Inventor: Kazuhiro Arimitsu
  • Publication number: 20010009853
    Abstract: A method for a mobile terminal to select a network system which enables the mobile terminal to be connected through a radio channel to the network system desired by a user at a time the mobile terminal has to switch the network system being connected due to lowering in signal reception levels.
    Type: Application
    Filed: January 2, 2001
    Publication date: July 26, 2001
    Inventor: Kazuhiro Arimitsu