Patents by Inventor Akinori Fujimura
Akinori Fujimura 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: 11777589Abstract: A satellite receiver includes: demultiplexing units each demultiplexing, into subchannel signals of a predetermined band, a digital reception signal obtained by converting a calibration signal received by a corresponding one of receiving antenna elements into a digital signal; excitation coefficient multiplication units multiplying the subchannel signals by an excitation coefficient; a complex adder adding the subchannel signals multiplied by the excitation coefficient together for each subchannel signal of the same band; a correlation detection unit calculating, with the use of one demultiplexing unit as a reference demultiplexing unit, a cross-correlation value for each subchannel signal output from each demultiplexing unit different from the reference demultiplexing unit with respect to a subchannel signal of a same band output from the reference demultiplexing unit; and an excitation coefficient generation unit generating a corrected excitation coefficient based on a cross-correlation value and an excitatType: GrantFiled: January 27, 2020Date of Patent: October 3, 2023Assignee: MITSUBISHI ELECTRIC CORPORATIONInventors: Akinori Fujimura, Hitomi Ono, Yoshio Inasawa, Masaaki Kusano
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Patent number: 11764868Abstract: A satellite transmitter includes K transmission antenna elements, a multiplexing unit configured to multiplex each of K digital signals on a frequency axis and then convert the multiplexed digital signals to time-domain digital signals, a digital-to-analog converter, a PAPR calculation unit configured to calculate a PAPR for each of the K digital signals, a beam-to-beam relative phase calculation unit configured to calculate a beam-to-beam relative phase for suppressing a peak power of the transmission antenna elements, an excitation coefficient calculation unit configured to calculate K updated excitation coefficients based on the beam-to-beam relative phase and the beam-formation excitation coefficient, and an excitation coefficient multiplication unit configured to generate the digital signals of a frequency domain to be output to the multiplexing unit by multiplying a received relay signal by each of the K updated excitation coefficients in the frequency domain.Type: GrantFiled: September 20, 2019Date of Patent: September 19, 2023Assignee: MITSUBISHI ELECTRIC CORPORATIONInventors: Hitomi Ono, Akinori Fujimura, Terumi Sunaga
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Publication number: 20230022974Abstract: A satellite receiver includes: demultiplexing units each demultiplexing, into subchannel signals of a predetermined band, a digital reception signal obtained by converting a calibration signal received by a corresponding one of receiving antenna elements into a digital signal; excitation coefficient multiplication units multiplying the subchannel signals by an excitation coefficient; a complex adder adding the subchannel signals multiplied by the excitation coefficient together for each subchannel signal of the same band; a correlation detection unit calculating, with the use of one demultiplexing unit as a reference demultiplexing unit, a cross-correlation value for each subchannel signal output from each demultiplexing unit different from the reference demultiplexing unit with respect to a subchannel signal of a same band output from the reference demultiplexing unit; and an excitation coefficient generation unit generating a corrected excitation coefficient based on a cross-correlation value and an excitatType: ApplicationFiled: January 27, 2020Publication date: January 26, 2023Applicant: Mitsubishi Electric CorporationInventors: Akinori FUJIMURA, Hitomi ONO, Yoshio INASAWA, Masaaki KUSANO
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Patent number: 11463378Abstract: Provided is a digital switch including: a plurality of input-side memories, which are arranged in a one-to-one correspondence with a plurality of input ports, and are configured to accumulate time-division multiplexed data; a plurality of output-side memories, which are arranged in a one-to-one correspondence with a plurality of output ports, and are configured to accumulate time-division multiplexed data; and a switch matrix configured to receive, as input, the time-division multiplexed data read out in every cycle from each of the plurality of input-side memories, and execute routing for selecting, in accordance with a connection control signal received from outside, any one of the plurality of output-side memories such that the time-division multiplexed data read out in every cycle is output from each of the plurality of output ports without causing a difference in delay, to output the time-division multiplexed data.Type: GrantFiled: March 6, 2018Date of Patent: October 4, 2022Assignee: MITSUBISHI ELECTRIC CORPORATIONInventors: Kazuyoshi Tsuji, Akinori Fujimura, Yuta Takemoto, Shinya Hirakuri, Yuichi Yamamoto
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Patent number: 11456812Abstract: A multi-stage demultiplexing circuit in which a plurality of circuits each combining a selector and a frequency decimation circuit are connected is included. The selector selects one of input signals based on a control signal, and generates a plurality of output signals. The plurality of output signals output from the selector are input to the frequency decimation circuit, and the frequency decimation circuit performs frequency conversion processing, low pass filter processing, and down-sampling processing based on a control signal to generate an output signal. Two or more reception signals are input to the multi-stage demultiplexing circuit, and the multi-stage demultiplexing circuit executes demultiplexing processing based on a control signal so that an output signal that includes an unused band portion is prevented from being output downstream.Type: GrantFiled: March 5, 2018Date of Patent: September 27, 2022Assignee: MITSUBISHI ELECTRIC CORPORATIONInventors: Yuta Takemoto, Akinori Fujimura, Yuichi Yamamoto
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Patent number: 11387894Abstract: A satellite receiver includes: N reception antenna elements; N demultiplexing units; a correlation detection unit configured to perform correlation processing on each of reception signals demultiplexed by the N demultiplexing units with a reception antenna element that receives the highest power being set as a reference element so as to calculate a relative phase difference, and calculate an excitation coefficient for cancelling a phase difference between the N reception antenna elements for each of sub-channels based on the calculated relative phase difference; N phase compensation units configured to multiply the reception signals demultiplexed by the N demultiplexing units, respectively, by the excitation coefficient for each of the sub-channels; and a combiner configured to combine multiplication results from the N phase compensation units for each of the sub-channels to generate output signals.Type: GrantFiled: January 30, 2019Date of Patent: July 12, 2022Assignee: MITSUBISHI ELECTRIC CORPORATIONInventors: Hitomi Ono, Akinori Fujimura, Terumi Sunaga, Toshiyasu Tsunoda
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Publication number: 20220085875Abstract: A satellite transmitter includes K transmission antenna elements, a multiplexing unit configured to multiplex each of K digital signals on a frequency axis and then convert the multiplexed digital signals to time-domain digital signals, a digital-to-analog converter, a PAPR calculation unit configured to calculate a PAPR for each of the K digital signals, a beam-to-beam relative phase calculation unit configured to calculate a beam-to-beam relative phase for suppressing a peak power of the transmission antenna elements, an excitation coefficient calculation unit configured to calculate K updated excitation coefficients based on the beam-to-beam relative phase and the beam-formation excitation coefficient, and an excitation coefficient multiplication unit configured to generate the digital signals of a frequency domain to be output to the multiplexing unit by multiplying a received relay signal by each of the K updated excitation coefficients in the frequency domain.Type: ApplicationFiled: September 20, 2019Publication date: March 17, 2022Applicant: Mitsubishi Electric CorporationInventors: Hitomi ONO, Akinori FUJIMURA, Terumi SUNAGA
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Patent number: 11271639Abstract: Provided is a communication system including a control station and a satellite repeater capable of forming two or more beams. The control station includes a control unit that classifies the two or more beams into clusters each made up of two or more beams among the two or more beams and allocates different frequencies to the beams belonging to one of the clusters. The satellite repeater includes a channelizer that performs exchanging processing on an input reception signal and outputs the reception signal having undergone the exchanging processing, as a transmission signal. A signal used in the exchanging processing includes a signal obtained by combining signals corresponding to the beams defining the one cluster.Type: GrantFiled: December 13, 2016Date of Patent: March 8, 2022Assignee: MITSUBISHI ELECTRIC CORPORATIONInventors: Shigenori Tani, Akinori Fujimura, Katsuyuki Motoyoshi, Tsuyoshi Sasaki, Futaba Ejima
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Publication number: 20210409141Abstract: A multi-stage demultiplexing circuit in which a plurality of circuits each combining a selector and a frequency decimation circuit are connected is included. The selector selects one of input signals based on a control signal, and generates a plurality of output signals. The plurality of output signals output from the selector are input to the frequency decimation circuit, and the frequency decimation circuit performs frequency conversion processing, low pass filter processing, and down-sampling processing based on a control signal to generate an output signal. Two or more reception signals are input to the multi-stage demultiplexing circuit, and the multi-stage demultiplexing circuit executes demultiplexing processing based on a control signal so that an output signal that includes an unused band portion is prevented from being output downstream.Type: ApplicationFiled: March 5, 2018Publication date: December 30, 2021Applicant: MITSUBISHI ELECTRIC CORPORATIONInventors: Yuta TAKEMOTO, Akinori FUJIMURA, Yuichi YAMAMOTO
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Publication number: 20210359753Abstract: Provided is a communication system including a control station and a satellite repeater capable of forming two or more beams. The control station includes a control unit that classifies the two or more beams into clusters each made up of two or more beams among the two or more beams and allocates different frequencies to the beams belonging to one of the clusters. The satellite repeater includes a channelizer that performs exchanging processing on an input reception signal and outputs the reception signal having undergone the exchanging processing, as a transmission signal. A signal used in the exchanging processing includes a signal obtained by combining signals corresponding to the beams defining the one cluster.Type: ApplicationFiled: December 13, 2016Publication date: November 18, 2021Applicant: Mitsubishi Electric CorporationInventors: Shigenori TANI, Akinori FUJIMURA, Katsuyuki MOTOYOSHI, Tsuyoshi SASAKI, Futaba EJIMA
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Publication number: 20210336900Abstract: Provided is a digital switch including: a plurality of input-side memories, which are arranged in a one-to-one correspondence with a plurality of input ports, and are configured to accumulate time-division multiplexed data; a plurality of output-side memories, which are arranged in a one-to-one correspondence with a plurality of output ports, and are configured to accumulate time-division multiplexed data; and a switch matrix configured to receive, as input, the time-division multiplexed data read out in every cycle from each of the plurality of input-side memories, and execute routing for selecting, in accordance with a connection control signal received from outside, any one of the plurality of output-side memories such that the time-division multiplexed data read out in every cycle is output from each of the plurality of output ports without causing a difference in delay, to output the time-division multiplexed data.Type: ApplicationFiled: March 6, 2018Publication date: October 28, 2021Applicant: MITSUBISHI ELECTRIC CORPORATIONInventors: Kazuyoshi TSUJI, Akinori FUJIMURA, Yuta TAKEMOTO, Shinya HIRAKURI, Yuichi YAMAMOTO
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Publication number: 20210119694Abstract: A satellite receiver includes: N reception antenna elements; N demultiplexing units; a correlation detection unit configured to perform correlation processing on each of reception signals demultiplexed by the N demultiplexing units with a reception antenna element that receives the highest power being set as a reference element so as to calculate a relative phase difference, and calculate an excitation coefficient for cancelling a phase difference between the N reception antenna elements for each of sub-channels based on the calculated relative phase difference; N phase compensation units configured to multiply the reception signals demultiplexed by the N demultiplexing units, respectively, by the excitation coefficient for each of the sub-channels; and a combiner configured to combine multiplication results from the N phase compensation units for each of the sub-channels to generate output signals.Type: ApplicationFiled: January 30, 2019Publication date: April 22, 2021Applicant: MITSUBISHI ELECTRIC CORPORATIONInventors: Hitomi ONO, Akinori FUJIMURA, Terumi SUNAGA, Toshiyasu TSUNODA
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Patent number: 10938467Abstract: A transmitting station includes a transmitting antenna whose orientation direction is changeable, and a controller that controls the orientation direction of the transmitting antenna according to an orientation direction of the transmitting antenna determined together with receiving stations to receive data transmitted from the transmitting antenna based on estimate values of received signal quality at receiving stations that are candidates for receiving stations to receive data transmitted from the transmitting antenna. The transmitting station can maintain received signal quality at a plurality of receiving stations at a desired value or more in a data transmission system.Type: GrantFiled: April 30, 2015Date of Patent: March 2, 2021Assignee: Mitsubishi Electric CorporationInventors: Shigenori Tani, Hiroyasu Sano, Katsuyuki Motoyoshi, Akinori Fujimura, Futaba Ejima, Kyoichiro Izumi
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Patent number: 10454567Abstract: A relay side receiving unit (931) receives a relay signal (99), an analog relay unit (932) outputs by analog processing the relay signal (99) whose frequency bandwidth is controlled, and a digital relay unit (933) outputs by digital processing the relay signal (99) whose frequency bandwidth is controlled. A relay side transmitting unit (934) transmits the relay signal (99) output by the analog relay unit (932), the digital relay unit (933). A relay side control unit (935) controls the analog relay unit (932), the digital relay unit (933) in accordance with an analog relay unit control signal (941A), a digital relay unit control signal (941D) indicating a frequency band of the relay signal (99).Type: GrantFiled: March 1, 2017Date of Patent: October 22, 2019Assignee: Mitsubishi Electric CorporationInventor: Akinori Fujimura
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Patent number: 10432251Abstract: A receiver includes a reception antenna, a reception unit, and a demodulation unit. The reception unit sequentially receives modulated signals resulting from spread spectrum via the reception antenna. The demodulation unit demodulate a first signal received by the reception unit by performing despreading using a short-period spreading code, the first signal including information for identifying a long-period spreading code. The demodulation unit identifies the long-period spreading code on the basis of the information obtained from the first signal. The demodulation unit then demodulates a second signal received by the reception unit after the first signal by performing despreading using the long-period spreading code.Type: GrantFiled: March 23, 2017Date of Patent: October 1, 2019Assignee: Mitsubishi Electric CorporationInventors: Makoto Yamazaki, Tomohiro Ogino, Akinori Fujimura
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Publication number: 20190089404Abstract: A receiver includes a reception antenna, a reception unit, and a demodulation unit. The reception unit sequentially receives modulated signals resulting from spread spectrum via the reception antenna. The demodulation unit demodulate a first signal received by the reception unit by performing despreading using a short-period spreading code, the first signal including information for identifying a long-period spreading code. The demodulation unit identifies the long-period spreading code on the basis of the information obtained from the first signal. The demodulation unit then demodulates a second signal received by the reception unit after the first signal by performing despreading using the long-period spreading code.Type: ApplicationFiled: March 23, 2017Publication date: March 21, 2019Applicant: Mitsubishi Electric CorporationInventors: Makoto YAMAZAKI, Tomohiro OGINO, Akinori FUJIMURA
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Publication number: 20190052351Abstract: A relay side receiving unit (931) receives a relay signal (99), an analog relay unit (932) outputs by analog processing the relay signal (99) whose frequency bandwidth is controlled, and a digital relay unit (933) outputs by digital processing the relay signal (99) whose frequency bandwidth is controlled. A relay side transmitting unit (934) transmits the relay signal (99) output by the analog relay unit (932), the digital relay unit (933). A relay side control unit (935) controls the analog relay unit (932), the digital relay unit (933) in accordance with an analog relay unit control signal (941A), a digital relay unit control signal (941D) indicating a frequency band of the relay signal (99).Type: ApplicationFiled: March 1, 2017Publication date: February 14, 2019Applicant: Mitsubishi Electric CorporationInventor: Akinori FUJIMURA
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Publication number: 20180145740Abstract: A transmitting station includes a transmitting antenna whose orientation direction is changeable, and a controller that controls the orientation direction of the transmitting antenna according to an orientation direction of the transmitting antenna determined together with receiving stations to receive data transmitted from the transmitting antenna based on estimate values of received signal quality at receiving stations that are candidates for receiving stations to receive data transmitted from the transmitting antenna. The transmitting station can maintain received signal quality at a plurality of receiving stations at a desired value or more in a data transmission system.Type: ApplicationFiled: April 30, 2015Publication date: May 24, 2018Applicant: Mitsubishi Electric CorporationInventors: Shigenori TANI, Hiroyasu SANO, Katsuyuki MOTOYOSHI, Akinori FUJIMURA, Futaba EJIMA, Kyoichiro IZUMI
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Patent number: 9923596Abstract: A demodulation apparatus demodulates spectrum-spread received data, and includes a band variable filter removing noise components from despread received data, a power conversion unit converting each sample value of received data after removing noise components to a power value, a cyclic addition unit cyclically adding the power value in bit periods of received data, a maximum-value detection/average-level measurement unit detecting a maximum value from a cyclic-addition result of the cyclic addition unit, an estimation unit estimating a spreading-code timing and a carrier frequency based on maximum-value information detected by the maximum-value detection/average-level measurement unit, a spreading-code generation unit generating a spreading code with a timing according to an estimation result of a spreading-code timing obtained by the estimation unit, and a local-signal generation unit setting a local-signal frequency according to an estimation result of a carrier frequency obtained by the estimation unit.Type: GrantFiled: May 15, 2014Date of Patent: March 20, 2018Assignee: MITSUBISHI ELECTRIC CORPORATIONInventor: Akinori Fujimura
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Patent number: 9917634Abstract: A relay apparatus includes a reception analog filter that extracts a desired signal from a received signal, an A/D converter that converts the signal after passage through the reception analog filter into a digital signal, a demultiplexing unit that demultiplexes the digital signal converted by the A/D converter into m signals, a reception-side compensating unit that digitally compensates for an analog characteristic of the reception analog filter with respect to the m signals demultiplexed by the demultiplexing unit, and a multiplexing unit that multiplexes the m signals digitally compensated by the reception-side compensating unit. The reception-side compensating unit further demultiplexes each of x signals not sufficiently compensated among the digitally-compensated m signals into k signals, digitally compensates for the analog characteristic of the reception analog filter, and multiplexes the k signals after the digital compensation.Type: GrantFiled: February 14, 2013Date of Patent: March 13, 2018Assignee: Mitsubishi Electric CorporationInventor: Akinori Fujimura