Patents by Inventor Tomoki Murakami
Tomoki Murakami 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: 11804881Abstract: A characteristic variable antenna configured to be able to select or switch antenna characteristics in accordance with a predetermined periodic variable timing, an RF unit configured to perform a reception process on a signal received by the characteristic variable antenna, an ADC unit configured to sample the analog signal input from the RF unit at a sampling period corresponding to the variable timing of the antenna characteristics of the characteristic variable antenna, a signal dividing unit configured to divide the digital signal input from the ADC unit into different digital signals in accordance with the antenna characteristics and output the divided different digital signals, a MIMO-OFDM demodulation unit configured to receive inputs of the different digital signals divided by the signal dividing unit and perform a demodulation process of predetermined MIMO-OFDM, and a control unit configured to periodically select or switch the antenna characteristics of the characteristic variable antenna in accordaType: GrantFiled: October 18, 2019Date of Patent: October 31, 2023Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Tomoki Murakami, Toshiro Nakahira, Riku Omiya, Koichi Ishihara, Takafumi Hayashi
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Patent number: 11804997Abstract: Interference in preamble signals and pilot signals in cooperative transmission using interference suppressing technology is avoided. A wireless apparatus for transmitting a wireless signal on which directivity control has been performed to stations in a wireless system including at least one wireless apparatus is provided with a known signal generating unit which generates a known signal to be added to the wireless signal, a weighting processing unit which performs weighting on the known signal generated by the known signal generating unit, and a wireless processing unit which transmits the known signal on which the weighting has been performed by the weighting processing unit.Type: GrantFiled: November 1, 2022Date of Patent: October 31, 2023Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Tomoki Murakami, Yusuke Asai, Riichi Kudo, Koichi Ishihara, Masato Mizoguchi, Takeo Ichikawa
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Patent number: 11765674Abstract: A wireless communications method for connecting a base station with each of a plurality of terminal stations set to differ in basic rate, the base station being equipped with a plurality of wireless communications units configured to be connectable with one or more of the terminal stations, includes: a collection step of collecting information about a transmission rate set for each of the terminal stations; a policy calculation step of calculating a setting policy for setting a basic rate permitted for each of the wireless communications units and a switching policy for setting a condition for switching that one of the wireless communications units which is to be connected, for each of the terminal stations, based on each item of the collected information about transmission rates; and a setting step of setting those of the terminal stations which are to be connected, for each of the wireless communications units based on the calculated setting policy and switching policy.Type: GrantFiled: March 11, 2020Date of Patent: September 19, 2023Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Toshiro Nakahira, Tomoki Murakami, Hirantha Abeysekera, Koichi Ishihara, Takafumi Hayashi, Yasushi Takatori
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Publication number: 20230275624Abstract: A reflection direction control method includes an arrival direction estimation step of estimating an arrival direction of radio waves transmitted by a wireless terminal to one or more reflection units each including a plurality of reflection elements capable of dynamically changing phase characteristics when the radio wave is reflected, a phase control step of controlling a phase of a radio wave reflected by each of the plurality of reflection elements so that the reflection unit reflects, in a predetermined direction, the radio wave transmitted from the estimated arrival direction, and a switching step of switching between an antenna mode in which the reflection unit is caused to receive the radio wave of which the arrival direction is estimated and a reflection mode in which the reflection unit is caused to reflect the radio wave.Type: ApplicationFiled: July 28, 2020Publication date: August 31, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Riku OMIYA, Masashi IWABUCHI, Tomoki MURAKAMI, Tomoaki OGAWA, Yasushi TAKATORI
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Publication number: 20230276255Abstract: The reflection direction control system includes a plurality of reflection units each including a plurality of reflection elements, a position estimation unit for estimating a position of each of the wireless terminals on the basis of radio waves transmitted to the plurality of reflection parts wireless terminals, a direction estimation unit for estimating an incident direction of the radio waves transmitted by each of the wireless terminals to the reflection units, a phase calculation unit for calculating a phase of the radio waves to be reflected so that the reflection unit reflects the radio waves made incident in the direction estimated by the direction estimation unit in a predetermined direction, and a phase control unit for controlling the phase of the radio waves reflected by each of the plurality of reflection elements on the basis of the phase calculated by the phase calculation unit.Type: ApplicationFiled: July 20, 2020Publication date: August 31, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Masashi IWABUCHI, Tomoaki OGAWA, Tomoki MURAKAMI, Riku OMIYA, Yasushi TAKATORI
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Publication number: 20230275622Abstract: A relay system includes: one or more radiation units configured to form a beam in a predetermined direction by radiating radio waves from each of a plurality of elements; a detection unit configured to detect a physical environment on a radio wave propagation path that affects the beam formed by the radiation unit; a direction determination unit configured to determine a direction in which the radiation unit should form the beam based on the physical environment detected by the detection unit; a phase calculation unit configured to calculate a phase of radio wave to be radiated by each of the plurality of elements such that the radiation unit forms a beam in the direction determined by the direction determination unit; and a phase control unit configured to control the phase of the radio wave radiated by each of the plurality of elements based on the phase calculated.Type: ApplicationFiled: July 28, 2020Publication date: August 31, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Masashi IWABUCHI, Tomoaki OGAWA, Tomoki MURAKAMI, Riku OMIYA, Yasushi TAKATORI
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Publication number: 20230276254Abstract: A reflection direction control system includes a reflection unit including a plurality of reflection elements, a direction estimation unit that estimates an incident direction of a radio wave transmitted by a base station to the reflection unit on the basis of base station position information indicating a preset position of the base station, a phase calculation unit that calculates a phase of the radio wave to be reflected by each of the plurality of reflection elements so that the reflection unit reflects the radio waves transmitted by the base station toward the wireless terminal on the basis of the position information of the wireless terminal received from the wireless terminal, and a phase control unit that controls the phase of the radio wave reflected by each of the plurality of reflection elements on the basis of the phase calculated phase calculation unit.Type: ApplicationFiled: July 20, 2020Publication date: August 31, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Masashi IWABUCHI, Tomoaki OGAWA, Tomoki MURAKAMI, Riku OMIYA, Yasushi TAKATORI
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Patent number: 11728904Abstract: In the present disclosure, a wireless base station apparatus sends out continuous light having a predetermined characteristic to a wireless terminal apparatus, and the wireless terminal apparatus selects authentication information corresponding to the predetermined characteristic, and transmits the authentication information to the wireless base station apparatus by RF wireless. When confirming that the received authentication information matches authentication information corresponding to the predetermined characteristic, the wireless base station apparatus permits information communication between the wireless terminal apparatus and an upper network.Type: GrantFiled: July 4, 2019Date of Patent: August 15, 2023Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Kazutaka Hara, Tomohiro Taniguchi, Ryota Shiina, Tomoki Murakami, Toshiro Nakahira
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Patent number: 11700560Abstract: The present disclosure aims to enable communication to be performed with stable quality even when a user uses a terminal while moving. In the wireless communication system according to the present disclose, a switching control unit 15 sets switching illuminance pth for maintaining illuminance of an optical signal received by a terminal 91 at requested illuminance corresponding to throughput or higher during the time until connection switching between the communication with an optical wireless access point 92 and the communication with an RF wireless access point 93 is completed, and when the received illuminance p becomes lower than the switching illuminance pth during connection with the optical wireless access point 92, the switching control unit 15 performs connection switching from the optical wireless communication to the RF wireless communication.Type: GrantFiled: June 20, 2019Date of Patent: July 11, 2023Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Ryota Shiina, Kazutaka Hara, Tomohiro Taniguchi, Tomoki Murakami, Toshiro Nakahira
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Publication number: 20230209510Abstract: A radio base station and a radio terminal perform radio communication based on a TDD scheme. A slot configuration includes allocation of a downlink period and an uplink period to the radio terminal. The relay reflects a signal transmitted from the radio base station or the radio terminal or receives and reradiates the signal to form a transmission path between the radio base station and the radio terminal. A relay characteristic includes a parameter determining a coverage area in which the transmission path is formed. A downlink relay characteristic during the downlink period and an uplink relay characteristic during the uplink period are not common but determined separately. Then, the relay characteristic during the downlink period is set to the downlink relay characteristic, and the relay characteristic during the uplink period is set to the uplink relay characteristic. In other words, the relay characteristic is switched between downlink communication and uplink communication.Type: ApplicationFiled: May 25, 2020Publication date: June 29, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Masashi IWABUCHI, Tomoaki OGAWA, Tomoki MURAKAMI
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Publication number: 20230204750Abstract: A wireless transmission device transmits a radio signal with a plurality of beam patterns and outputs transmission beam identifiers corresponding to the beam patterns to an object detection device, a wireless reception device receives the radio signal transmitted by the wireless transmission device with a plurality of beam patterns, measures received signal strength for each of the beam patterns and outputs reception beam identifiers and the received signal strength to the object detection device, and the object detection device detects an object within a detection area on the basis of the transmission beam identifiers, the reception beam identifiers and the received signal strength. This enables device-free object detection by utilizing a beamforming function, so that it is possible to achieve high detection accuracy while preventing increase in cost.Type: ApplicationFiled: May 15, 2020Publication date: June 29, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Tomoki MURAKAMI, Shinya OTSUKI, Masashi IWABUCHI, Tomoaki OGAWA
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Publication number: 20230171624Abstract: Communication is performed between a radio base station and a radio terminal via a reflector. The radio base station transmits a measurement signal including a beam ID of a transmission beam for measuring communication quality between the radio base station and the radio terminal. The reflector reflects the measurement signal incident on the reflector in multiple reflection directions to generate multiple reflected measurement signals. Moreover, the reflector modulates the incident measurement signal during reflection to add information about a reflection direction ID being different for each of the multiple reflection directions to each of the multiple reflected measurement signals. The radio terminal demodulates a reflected measurement signal received from the reflector to acquire the reflection direction ID and the beam ID.Type: ApplicationFiled: May 27, 2020Publication date: June 1, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Masashi IWABUCHI, Tomoaki OGAWA, Tomoki MURAKAMI
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Publication number: 20230136032Abstract: An object of the present disclosure is to make already installed smart lightings available as optical base stations as they are without modifying them, and perform connection/authentication control for RF communication using an optical signal sent out from the optical base stations.Type: ApplicationFiled: April 2, 2020Publication date: May 4, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Ryota SHIINA, Tomohiro TANIGUCHI, Kazutaka HARA, Shinya TAMAKI, Tomoki MURAKAMI, Toshiro NAKAHIRA
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Patent number: 11641659Abstract: [Problem] A base station includes a plurality of radio communication units individually supporting a plurality of communication capabilities, and controls a terminal station to be connected with the base station to select a radio communication unit according to a communication scheme of the terminal station. [Solution] Provided is a radio communication method of a radio communication system. The radio communication system includes a plurality of base stations mounted with a plurality of radio communication units for which different communication schemes are settable, a terminal station configured to perform radio communication in a certain communication scheme, and a centralized control station configured to control the plurality of base stations.Type: GrantFiled: February 25, 2019Date of Patent: May 2, 2023Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Toshiro Nakahira, Tomoki Murakami, Hirantha Abeysekera, Akiyoshi Inoki, Keisuke Wakao
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Publication number: 20230130486Abstract: An object of the present disclosure is to inform a user of a safe evacuation guidance route in real time using smart lightings without deploying dedicated evacuation guidance facilities. The present disclosure is a wireless communication system including: one or more wireless base stations that wirelessly communicate with a terminal; a plurality of optical base stations that transmit an optical signal to the terminal; and a base station control device that controls the optical signal transmitted by the optical base stations, wherein the base station control device collects environment information around the optical base stations, detects a disaster around the optical base stations using the collected environment information, and when detecting a disaster, causes the optical base station installed at a position close to a disaster occurrence location and the optical base station installed at a position far from the disaster occurrence location to output light of different colors.Type: ApplicationFiled: April 2, 2020Publication date: April 27, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Ryota SHIINA, Tomohiro TANIGUCHI, Kazutaka HARA, Shinya TAMAKI, Tomoki MURAKAMI, Toshiro NAKAHIRA
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Publication number: 20230114692Abstract: A wireless communication system according to an embodiment includes: a wireless base station device configured to perform wireless communication of an orthogonal frequency division multiplexing (OFDM) method; a plurality of dynamic control relay devices for which a reradiation direction of incoming waves is dynamically controllable; and a wireless terminal device configured to perform wireless communication with the wireless base station device. The wireless base station device performs wireless communication with the wireless terminal device using a plurality of propagation paths that go through or do not go through the dynamic control relay devices, and a CP control unit provided in the wireless base station device changes the cyclic prefix length based on whether or not a propagation route from the wireless base station device to the wireless terminal device uses any dynamic control relay device.Type: ApplicationFiled: March 18, 2020Publication date: April 13, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Masashi IWABUCHI, Tomoaki OGAWA, Tomoki MURAKAMI
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Publication number: 20230114389Abstract: A passive relay device (100) relays radio communication between the inside of a radio wave shielding structure (200) and the outside of the radio wave shielding the structure (200), and the device includes an internal antenna (10) which connects with the inside, an external antenna (20) which connects with the outside, and a connection part (30) which connects the internal antenna (10) and the external antenna (20).Type: ApplicationFiled: February 6, 2020Publication date: April 13, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Yosuke TAKEUCHI, Hisatoshi KASAHARA, Yosuke OKAMURA, Junichiro TAMAMATSU, Tomoki MURAKAMI
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Publication number: 20230085726Abstract: A wireless communication system according to an embodiment includes: a wireless base station device configured to perform wireless communication of an orthogonal frequency division multiplexing (OFDM) method; a plurality of dynamic control relay devices for which a reradiation direction of incoming waves is dynamically controllable by the wireless base station device; and a wireless terminal device configured to perform wireless communication with the wireless base station device using a plurality of propagation paths that go through or do not go through the dynamic control relay devices.Type: ApplicationFiled: March 18, 2020Publication date: March 23, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Masashi IWABUCHI, Tomoaki OGAWA, Tomoki MURAKAMI
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Patent number: 11601879Abstract: [Problem] The base station includes a plurality of radio communication units configured to individually support a plurality of communication capabilities, and performs, for a terminal station that is connected to the base station, control for selecting a radio communication unit based on a communication scheme supported in the terminal station. [Solution] Provided is a radio communication method for a radio communication system including a plurality of base stations provided with a plurality of radio communication units for which different communication schemes are settable, and a terminal station configured to perform radio communication with the radio communication unit of the base station by using a specific communication scheme.Type: GrantFiled: February 25, 2019Date of Patent: March 7, 2023Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Tomoki Murakami, Toshiro Nakahira, Hirantha Abeysekera, Akiyoshi Inoki, Keisuke Wakao
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Publication number: 20230049652Abstract: Interference in preamble signals and pilot signals in cooperative transmission using interference suppressing technology is avoided. A wireless apparatus for transmitting a wireless signal on which directivity control has been performed to stations in a wireless system including at least one wireless apparatus is provided with a known signal generating unit which generates a known signal to be added to the wireless signal, a weighting processing unit which performs weighting on the known signal generated by the known signal generating unit, and a wireless processing unit which transmits the known signal on which the weighting has been performed by the weighting processing unit.Type: ApplicationFiled: November 1, 2022Publication date: February 16, 2023Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Tomoki MURAKAMI, Yusuke ASAI, Riichi KUDO, Koichi ISHIHARA, Masato MIZOGUCHI, Takeo ICHIKAWA