Patents by Inventor Tadashi Ogami
Tadashi Ogami 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).
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Patent number: 9730130Abstract: A mobile communication system according to an exemplary aspect of the invention is a mobile communication system including a mobile station, a radio base station as a handover source of the mobile station, and a radio base station as a handover target of the mobile station, wherein the mobile station includes a transmission unit for transmitting radio quality information between the mobile station and the radio base station as the handover target to the radio base station as the handover source; and the radio base station as the handover source includes a transmission unit for transmitting the radio quality information to the radio base station as the handover target.Type: GrantFiled: November 21, 2007Date of Patent: August 8, 2017Assignee: NEC CORPORATIONInventors: Tadashi Ogami, Sadafuku Hayashi, Mazlyn Mona Mustapha
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Publication number: 20080171538Abstract: A mobile communication system in which a specific user occupies and uses a base station is provided. A base station allows a downlink signal to include not only a base station ID number indicating the base station but also an identification signal for specific use indicating that the base station is for specific use and sends the downlink signal. The terminal includes a memory (25) that stores a list of base station ID numbers of an accessible base station or an inaccessible base station every identification signal for specific use, and searches whether or not the base station ID number in the received downlink signal is in the list of base station ID number every detected identification signal for specific use in the memory when the identification signal for specific use detected from the downlink signal is ON and performs communication with the base station only when the access is OK.Type: ApplicationFiled: March 25, 2005Publication date: July 17, 2008Applicant: NEC CorporationInventors: Kosuke Naito, Tadashi Ogami
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Publication number: 20080153495Abstract: A mobile communication system according to an exemplary aspect of the invention is a mobile communication system including a mobile station, a radio base station as a handover source of the mobile station, and a radio base station as a handover target of the mobile station, wherein the mobile station includes a transmission unit for transmitting radio quality information between the mobile station and the radio base station as the handover target to the radio base station as the handover source; and the radio base station as the handover source includes a transmission unit for transmitting the radio quality information to the radio base station as the handover target.Type: ApplicationFiled: November 21, 2007Publication date: June 26, 2008Applicant: NEC CorporationInventors: Tadashi Ogami, Sadafuku Hayashi, Mazlyn Mona Mustapha
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Publication number: 20070238463Abstract: Upon receipt of a trigger for resource allocation, User #n reception control unit 31 of target base station 3 notifies resources of User #n of radio parameters between a source base station and user equipment, received in the trigger for resource allocation, and issues a pilot symbol reception start trigger to User #n demodulator 32. Upon receipt of the reception start trigger, user #n demodulator 32 starts capturing a pilot symbol in accordance with specified parameters. User #n demodulator 32 issues a timing pull-in completion notice to User #n reception control unit 31 after the timing pull-in has been completed in the pilot symbol capture operation.Type: ApplicationFiled: April 4, 2007Publication date: October 11, 2007Applicant: NEC CORPORATIONInventor: Tadashi Ogami
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Patent number: 7218945Abstract: A transmission power controlling method and a base station apparatus capable of limiting total downlink transmission power while keeping adverse effects on common channels to a minimum. There is provided the transmission power controlling method for limiting total downlink transmission power for transmission from the base station to subject user terminals to less than or equal to a specified maximum value of total downlink transmission power in a mobile communication wireless network in which a plurality of wireless base stations execute adaptive transmission-power control by setting TPC bits in a wireless line in which user terminals have multiple access, wherein, when the value of the total downlink transmission power approximates to the maximum value, a base station apparatus restrains an increase in transmission power of a dedicated line to a user terminal, which is required to be increased at a next time slot.Type: GrantFiled: December 18, 2002Date of Patent: May 15, 2007Assignee: NEC CorporationInventor: Tadashi Ogami
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Patent number: 7149477Abstract: A radio-parameter control method allowing fine radio-parameter setting to improve communication quality is disclosed. Fixed stations are distributed at predetermined locations in a service area. A fixed station monitors reception condition of a pilot channel signal and transmits the monitored condition data back to a corresponding base station. A radio network control station statistically analyzes the monitored condition for each fixed station and estimates a future location of a mobile station. Radio parameters for use in radio communication between the mobile station and a base station corresponding to the future location of the mobile station are controlled based on statistical condition data at the future location of the mobile station.Type: GrantFiled: January 28, 2004Date of Patent: December 12, 2006Assignee: Nec CorporationInventor: Tadashi Ogami
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Patent number: 7082155Abstract: A reception level measuring system in which a base station in a code division multiple access (CDMA) mobile communication system measures a reception level of a signal from a mobile station. The reception level measuring system has an approximate-line estimating device, a phase-rotation estimating device; a Doppler-frequency estimating device and a reception signal power estimating device. The approximate-line estimating device provides an approximate line by linearly approximating signal amplitudes of a demodulated data stream in I- and Q-channels from a reception signal, in a time interval which is set in accordance with an estimated Doppler frequency. The phase-rotation estimating device estimates an amount of phase rotation based on a gradient of the approximated line. The Doppler-frequency estimating device estimates the estimated Doppler frequency based on the amount of phase rotation; and the reception signal power estimating device estimates a reception signal power based on said approximate line.Type: GrantFiled: August 11, 2000Date of Patent: July 25, 2006Assignee: NEC CorporationInventor: Tadashi Ogami
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Patent number: 7042931Abstract: A path detection method comprises; a correlator which receives input of a baseband signal converted to a digital signal in a wireless receiver, and which takes a reverse spread produced by the multiplication of the baseband signal and a spread code pilot symbol and outputs a correlation signal; an in-phase adder which, in each time slot, adds the correlation signal for the time slot a predetermined number of times, a first addition results storage memory for adding for the predetermined number of times, a second addition results storage memory for storing the addition results from the aforementioned in-phase adder when the addition is completed the predetermined number of times in the aforementioned time slot, an electric power adder for batch reading the results for each time slot from the aforementioned second addition results storage memory and performing addition, and a path detection apparatus which executes a path detection according to the output of the aforementioned electric power adder.Type: GrantFiled: May 17, 2001Date of Patent: May 9, 2006Assignee: NEC CorporationInventor: Tadashi Ogami
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Publication number: 20040185863Abstract: A radio-parameter control method allowing fine radio-parameter setting to improve communication quality is disclosed. Fixed stations are distributed at predetermined locations in a service area. A fixed station monitors reception condition of a pilot channel signal and transmits the monitored condition data back to a corresponding base station. A radio network control station statistically analyzes the monitored condition for each fixed station and estimates a future location of a mobile station. Radio parameters for use in radio communication between the mobile station and a base station corresponding to the future location of the mobile station are controlled based on statistical condition data at the future location of the mobile station.Type: ApplicationFiled: January 28, 2004Publication date: September 23, 2004Inventor: Tadashi Ogami
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Publication number: 20030119542Abstract: A transmission power controlling method and a base station apparatus capable of limiting total downlink transmission power while keeping adverse effects on common channels to a minimum. There is provided the transmission power controlling method for limiting total downlink transmission power for transmission from the base station to subject user terminals to less than or equal to a specified maximum value of total downlink transmission power in a mobile communication wireless network in which a plurality of wireless base stations execute adaptive transmission-power control by setting TPC bits in a wireless line in which user terminals have multiple access, wherein, when the value of the total downlink transmission power approximates to the maximum value, a base station apparatus restrains an increase in transmission power of a dedicated line to a user terminal, which is required to be increased at a next time slot.Type: ApplicationFiled: December 18, 2002Publication date: June 26, 2003Applicant: NEC CorporationInventor: Tadashi Ogami
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Patent number: 6522686Abstract: A receiving apparatus of spectrum spread communication system, which has optimum detection characteristics for receiving signals irrespectively of various fading pitches in fading environment, is realized. In a receiving apparatus used in a code division multiple access system, two types of detection circuits are provided, one detection circuit having optimum detection characteristics under low speed fading environment and another detection circuit having optimum detection characteristics under high speed fading environment, and an output signal having better detection result of one of detection circuits is determined by a detection output selection circuit. The output of determined detection circuit is selected by a selector as an output signal of this receiving apparatus.Type: GrantFiled: March 30, 2000Date of Patent: February 18, 2003Assignee: NEC CorporationInventor: Tadashi Ogami
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Patent number: 6430171Abstract: A random access channel receiver used in a base station of a CDMA mobile communication system is provided. The receiver is only provided with a single signal decoding part for performing burst reception of control request signals having different off-set timing each other. A synchronizing circuit calculates correlation value at each off-set timing, and a synchronism determining and establishing circuit determines the off-set timing to be used for a synchronizing signal for receiving the signal frame currently arriving by monitoring correlation values of respective off-set timings, and alters the off-set timing for the synchronizing signal to better quality of signal if a plurality of signal frames of different off-set timing are arrived. The signal frame of less quality is discarded, or abandoned its decoding processing.Type: GrantFiled: July 27, 1999Date of Patent: August 6, 2002Assignee: NEC CorporationInventors: Tadashi Ogami, Yoshihiro Unno
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Publication number: 20010043643Abstract: A path detection method comprises; a correlator which receives input of a baseband signal converted to a digital signal in a wireless receiver, and which takes a reverse spread produced by the multiplication of the baseband signal and a spread code pilot symbol and outputs a correlation signal; an in-phase adder which, in each time slot, adds the correlation signal for the time slot a predetermined number of times, a first addition results storage memory for adding for the predetermined number of times, a second addition results storage memory for storing the addition results from the aforementioned in-phase adder when the addition is completed the predetermined number of times in the aforementioned time slot, an electric power adder for batch reading the results for each time slot from the aforementioned second addition results storage memory and performing addition, and a path detection apparatus which executes a path detection according to the output of the aforementioned electric power adder.Type: ApplicationFiled: May 17, 2001Publication date: November 22, 2001Applicant: NEC CORPORATIONInventor: Tadashi Ogami