Patents by Inventor Akihiro Higashi
Akihiro Higashi 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: 7437152Abstract: A control method of searching for a neighboring cell of a mobile station communicating with a base-station is provided in a direct sequence CDMA mobile communication system which transmits information by carrying out double modulation using a first spreading code group and a second spreading code. The first spreading code group includes spreading codes that have a same repetition period as an information symbol period and are used in common by the base stations, and the second spreading code has a repetition period longer than the information symbol period. The base stations are assigned different second spreading codes.Type: GrantFiled: September 18, 2003Date of Patent: October 14, 2008Assignee: NTT DoCoMo, Inc.Inventors: Yoshihiro Ishikawa, Seizo Onoe, Kazufumi Yunoki, Akihiro Higashi
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Patent number: 7240216Abstract: Information stored in an IC card which can be set to a block state, where any functions permitted to a user authority holder is not effective and an unblock password is required to set the IC card back to an initial state, is more secured than that stored in an IC card without the block state. The IC card of the present invention is further provided with a counter counting the number of incorrect unblock passwords, and is set to a more secured state of operation where only administrative authority holder can release the IC card.Type: GrantFiled: December 12, 2001Date of Patent: July 3, 2007Assignee: NTT DoCoMo, Inc.Inventors: Hidetoshi Ishikawa, Yukio Yamauchi, Kanehiro Imai, Akihiro Higashi
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Publication number: 20070121706Abstract: A spreading and/or despreading mechanism in which the inphase component and a quadrature component of a signal are to be transmitted by using a short code and a long code. The long code has an inphase component and a quadrature component that are different from each other. The spreading and despreading operations carry out a complex-to-complex operation between a combination of the inphase component and the quadrature component of the signal and a combination of the inphase component and the quadrature component of the long code.Type: ApplicationFiled: January 31, 2007Publication date: May 31, 2007Applicant: NTT DoCoMo, Inc.Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Publication number: 20060251151Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: ApplicationFiled: July 11, 2006Publication date: November 9, 2006Applicant: NTT DoCoMo, Inc.Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Patent number: 7095780Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: GrantFiled: September 29, 2003Date of Patent: August 22, 2006Assignee: NTT DoCoMo, Inc.Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Patent number: 6782035Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels.Type: GrantFiled: January 31, 2000Date of Patent: August 24, 2004Assignee: NTT Docomo Inc.Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Publication number: 20040136336Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: ApplicationFiled: September 29, 2003Publication date: July 15, 2004Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Patent number: 6738411Abstract: An exclusive OR of outputs from a plurality of shift stages of an M-series generator is formed, thereby obtaining an M-series which has a desired delay, which in an example is a three bit delay with respect to the output code from the generator. Similarly, outputs from a plurality of shift stages are combined and an exclusive OR thereof is formed to provide another delayed M-series. An exclusive OR of each output from the simultaneously delayed code generator and an output from another M-series generator is formed, thus simultaneously obtaining a plurality of Gold code series.Type: GrantFiled: March 16, 1999Date of Patent: May 18, 2004Assignee: NTT Mobile Communications Network Inc.Inventors: Shinsuke Ogawa, Hirofumi Takagi, Akihiro Higashi
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Publication number: 20040085916Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: ApplicationFiled: September 29, 2003Publication date: May 6, 2004Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Patent number: 6728305Abstract: A CDMA radio receiver includes a plurality of reception fingers for effecting a dispreading of a received signal with a plurality of spread codes to derive received data. The receiver includes a plural code generator for simultaneously generating and supplying spread codes to the plurality of reception fingers, and a controller for designating a plurality of spread codes which are to be generated and supplied to the plural code series generator and for specifying to which finger they are to be supplied. The plural code series generator includes a shift register having a plurality of shift stages in which a first initial value is loaded by the controller and adapted to be subject to a shift operation in synchronism with a clock.Type: GrantFiled: June 21, 2002Date of Patent: April 27, 2004Assignee: NTT Mobile Communications Network, Inc.Inventors: Shinsuke Ogawa, Hirofumi Takagi, Akihiro Higashi
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Publication number: 20040076125Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: ApplicationFiled: September 29, 2003Publication date: April 22, 2004Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Publication number: 20040071220Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: ApplicationFiled: September 29, 2003Publication date: April 15, 2004Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Publication number: 20040072572Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: ApplicationFiled: September 29, 2003Publication date: April 15, 2004Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Publication number: 20040071119Abstract: A control method of searching for a neighboring cell of a mobile station communicating with a base-station is provided in a direct sequence CDMA mobile communication system which transmits information by carrying out double modulation using a first spreading code group and a second spreading code. The first spreading code group includes spreading codes that have a same repetition period as an information symbol period and are used in common by the base stations, and the second spreading code has a repetition period longer than the information symbol period. The base stations are assigned different second spreading codes.Type: ApplicationFiled: September 18, 2003Publication date: April 15, 2004Inventors: Yoshihiro Ishikawa, Seizo Onoe, Kazufumi Yunoki, Akihiro Higashi
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Publication number: 20040071248Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: ApplicationFiled: September 29, 2003Publication date: April 15, 2004Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Publication number: 20040071192Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: ApplicationFiled: September 29, 2003Publication date: April 15, 2004Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Publication number: 20040062321Abstract: A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels by mapping logical channels into physical channels. The CDMA signals are spread using a short code and a long code.Type: ApplicationFiled: September 29, 2003Publication date: April 1, 2004Inventors: Takehiro Nakamura, Junichiro Hagiwara, Etsuhiro Nakano, Koji Ohno, Seizo Onoe, Akihiro Higashi, Motoshi Tamura, Masatomo Nakano, Hiroshi Kawakami, Hiroki Morikawa
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Patent number: 6697622Abstract: A control method of searching for a neighboring cell of a mobile station communicating with a base station is provided in a direct sequence CDMA mobile communication system which transmits information by carrying out double modulation using a first spreading code group and a second spreading code. The first spreading code group includes spreading codes that have a same repetition period as an information symbol period and are used in common by the base stations, and the second spreading code has a repetition period longer than the information symbol period. The base stations are assigned different second spreading codes.Type: GrantFiled: September 5, 2000Date of Patent: February 24, 2004Assignee: NIT DoCoMo, Inc.Inventors: Yoshihiro Ishikawa, Seizo Onoe, Kazufumi Yunoki, Akihiro Higashi
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Patent number: 6556552Abstract: In CDMA mobile communication systems, there are cases in which communications are interrupted with the local base station while the mobile station is searching for channels other than the communication channel. A method is offered of preventing loss of information due to interruptions in such a case. There are a first transmission step for transmitting signals from the mobile station to the base station at a transmission rate R1 and a transmission output level P1 (when the transmission output is p in FIG. 10C), a suspension step of suspending signal transmissions from the mobile station to the base station (when no transmission output power as shown in the same drawing), and a second transmission step of transmitting signals from the mobile station to the base station at a transmission rate R2 higher than the transmission rate R1 and a transmission output level P2 higher than the transmission output level P1 (when 2p in the same drawing).Type: GrantFiled: December 21, 1999Date of Patent: April 29, 2003Assignee: NTT Communications Networks, Inc.Inventors: Hisashi Nakagomi, Tadao Takami, Akihiro Higashi, Kiyohito Nagata
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Publication number: 20020181558Abstract: An EOR (XR11, XR12) of outputs from a plurality of shift stages S1, S2, S4 of an M-series generator 31A is formed, thereby obtaining an M-series which has a desired delay, which in an example is a three bit delay with respect to the output code from the generator 31A. Similarly, outputs from a plurality of shift stages are combined and an EOR thereof is formed to provide another delayed M-series. An EOR of each output from the simultaneously delayed code generator 31 and an output from other M-series generator 32 is formed, thus simultaneously obtaining a plurality of Gold code series.Type: ApplicationFiled: June 21, 2002Publication date: December 5, 2002Applicant: NTT Mobile Communications Network, Inc.Inventors: Shinsuke Ogawa, Hirofumi Takagi, Akihiro Higashi