Patents by Inventor Toshiaki Koike-Akino

Toshiaki Koike-Akino 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: 10921525
    Abstract: A grating coupler having first and second ends for coupling a light beam to a waveguide of a chip includes a substrate configured to receive the light beam from the first end and transmit the light beam through the second end, the substrate having a first refractive index n1, a grating structure having curved grating lines arranged on the substrate, the grating structure having a second refractive index n1, wherein the curved grating lines have line width w and height d and are arranged by a pitch ?, wherein the second refractive index n2 is less than first refractive index n1, and a cladding layer configured to cover the grating structure, wherein the cladding layer has a third refractive index n3.
    Type: Grant
    Filed: January 29, 2019
    Date of Patent: February 16, 2021
    Assignees: Mitsubishi Electric Research Laboratories, Inc., Mitsubishi Electric Corporation
    Inventors: Keisuke Kojima, Mitsunobu Gotoda, Toshiaki Koike-Akino, Mohammad Tahersima
  • Patent number: 10862621
    Abstract: A transmitter for transmitting an encoded codeword over a communication channel includes a source to accept source data, an irregular polar encoder operated by a processor to encode the source data with at least one polar code to produce the encoded codeword, a modulator to modulate the encoded codeword, and a front end to transmit the modulated and encoded codeword over the communication channel. The polar code is specified by a set of regular parameters including one or combination of parameters defining a number of data bits in the codeword, a parameter defining a data index set specifying locations of frozen bits in the encoded codeword, and a parameter defining a number of parity bits in the encoded codeword.
    Type: Grant
    Filed: January 30, 2019
    Date of Patent: December 8, 2020
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Toshiaki Koike-Akino, Ye Wang, Stark C Draper
  • Patent number: 10859769
    Abstract: A photonic device for splitting optical beams includes an input port configured to receive an input beam having an input power, a power splitter including perturbation segments arranged in a first region and a second region of a guide material having a first refractive index, each segment having a second refractive index, wherein the first region is configured to split the input beam into a first beam and a second beam, wherein and the second region is configured to separately guide the first and second beams, wherein the first refractive index is greater than the second refractive index, and output ports including first and second output ports connected the power splitter to respectively receive and transmit the first and second beams.
    Type: Grant
    Filed: December 10, 2018
    Date of Patent: December 8, 2020
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Keisuke Kojima, Mohammad hossein Taher sima, Toshiaki Koike-Akino
  • Patent number: 10838282
    Abstract: An optical ring circuit for modulating light from a light source into an optical signal includes a ring modulator located near a waveguide to couple a light propagating the waveguide, the ring modulator including a pair of electrodes, a signal generator to transmit an electrical signal corresponding to the optical signal, a filter circuit to generate an output signal, wherein the filter circuit includes an adder unit and at least one tap unit having a delay unit and a coefficient unit, wherein the adder unit adds the electrical signal from the signal generator and a signal passed from the tap unit for pre-compensating signal components of the electrical signal by at least twice delay time of the delay unit, and a driver circuit to apply a voltage to the electrodes based on the output signal.
    Type: Grant
    Filed: September 7, 2018
    Date of Patent: November 17, 2020
    Assignees: Mitsubishi Electric Research Laboratories, Inc., Mitsubishi Electric Corporation
    Inventors: Keisuke Kojima, Min Teng, Toshiaki Koike-Akino, Chungwei Lin, Kieran Parsons, Mitsunobu Gotoda, Koichi Akiyama
  • Patent number: 10809701
    Abstract: A control system for controlling a plant includes a local controller to generate local control commands according to a local control policy to control the plant and a receiver to received remote control commands generated by a remote controller to control the plant according to remote control policy. Local and remote control policies are designed for the same control objective and time resolution such that there is the same Lyapunov function having a negative definite time derivative for controlling the plant according to first or second control policies. The plant is controller with either remote or local control commands in dependence of a success of receiving a remote control command for a time step of the control.
    Type: Grant
    Filed: December 13, 2018
    Date of Patent: October 20, 2020
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Yebin Wang, Yehan Ma, Philip Orlik, Toshiaki Koike-Akino, Jianlin Guo
  • Patent number: 10795151
    Abstract: An encoder of a terahertz (THz)-based absolute positioning system used for decoding patterns from THz-band measurements. The encoder includes a scale with a multi-layer reflective/transmissive structure having a matrix with rows. Each row of the matrix corresponds to a plurality of patterns, such that each pattern is used to form a measurement. An emitter emits a THz waveform to the scale. A receiver is used to measure amplitudes of the THz waveform reflected from the scale. A memory stores data including predetermined positions of the emitter based on the patterns of the layers from the scale. Wherein one or more processors can determine a position of the emitter from the measurements of the amplitudes received by the receiver, based on the stored data. An output interface can be used to render the position of the emitter.
    Type: Grant
    Filed: April 12, 2018
    Date of Patent: October 6, 2020
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Pu Wang, Haoyu Fu, Philip Orlik, Toshiaki Koike-Akino, Rui Ma, Bingnan Wang
  • Patent number: 10749554
    Abstract: A communication system transmits an input block of bits over a communication channel using a prefix tree that maps a dyadic distribution of compositions of output symbols to prefixes of variable lengths. A path to each leaf of the prefix tree is defined by a prefix formed by a unique sequence of binary values of a length equal to a depth of the leaf. Each leaf is associated with a composition that has at least a number of unique permutations equals to two in a power of a length of a suffix of the block of input bits. The system selects a composition identified in the prefix tree by a prefix, permutes the selected composition according to a suffix, and transmits the permuted composition over a communication channel. The compositions are selected to reduce one or combination of energy and kurtosis of transmission.
    Type: Grant
    Filed: October 2, 2019
    Date of Patent: August 18, 2020
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: David Millar, Toshiaki Koike-Akino, Kieran Parsons, Keisuke Kojima
  • Publication number: 20200241204
    Abstract: A grating coupler having first and second ends for coupling a light beam to a waveguide of a chip includes a substrate configured to receive the light beam from the first end and transmit the light beam through the second end, the substrate having a first refractive index n1, a grating structure having curved grating lines arranged on the substrate, the grating structure having a second refractive index n1, wherein the curved grating lines have line width w and height d and are arranged by a pitch ?, wherein the second refractive index n2 is less than first refractive index n1, and a cladding layer configured to cover the grating structure, wherein the cladding layer has a third refractive index n3.
    Type: Application
    Filed: February 28, 2020
    Publication date: July 30, 2020
    Applicants: Mitsubishi Electric Research Laboratories, Inc., Mitsubishi Electric Corporation
    Inventors: Keisuke Kojima, Mitsunobu Gotoda, Toshiaki Koike-Akino, Mohammad Tahersima
  • Publication number: 20200241205
    Abstract: A grating coupler having first and second ends for coupling a light beam to a waveguide of a chip includes a substrate configured to receive the light beam from the first end and transmit the light beam through the second end, the substrate having a first refractive index n1, a grating structure having curved grating lines arranged on the substrate, the grating structure having a second refractive index n1, wherein the curved grating lines have line width w and height d and are arranged by a pitch ?, wherein the second refractive index n2 is less than first refractive index n1, and a cladding layer configured to cover the grating structure, wherein the cladding layer has a third refractive index n3.
    Type: Application
    Filed: February 28, 2020
    Publication date: July 30, 2020
    Applicants: Mitsubishi Electric Research Laboratories, Inc., Mitsubishi Electric Corporation
    Inventors: Keisuke Kojima, Mitsunobu Gotoda, Toshiaki Koike-Akino, Muhammad Tahersima
  • Publication number: 20200229730
    Abstract: Devices, systems and methods for a brain-computer interface (BCI) system for correlating brain activity of a user to a predetermined physiological response, a predetermined classification of a user intention or a predetermined mental state to control, for actuating a control action. The BCI system including an input interface to receive brain signals indicative of an activity of a brain of the user. An encoder to encode the received brain signals to produce a sparse connectivity map of correlations among active regions of the brain. Wherein the sparse connectivity map specifies more zero correlations than non-zero correlations between various active regions of the brain. A classifier to classify the sparse connectivity map as an intended predetermined physiological response intended by the user. A controller to communicate a control signal for actuating the control action according to the intended predetermined physiological response to a device.
    Type: Application
    Filed: January 17, 2019
    Publication date: July 23, 2020
    Applicant: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Pu Wang, Toshiaki Koike-Akino, Ye Wang
  • Publication number: 20200192336
    Abstract: A control system for controlling a plant includes a local controller to generate local control commands according to a local control policy to control the plant and a receiver to received remote control commands generated by a remote controller to control the plant according to remote control policy. Local and remote control policies are designed for the same control objective and time resolution such that there is the same Lyapunov function having a negative definite time derivative for controlling the plant according to first or second control policies. The plant is controller with either remote or local control commands in dependence of a success of receiving a remote control command for a time step of the control.
    Type: Application
    Filed: December 13, 2018
    Publication date: June 18, 2020
    Applicant: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Yebin Wang, Yehan Ma, Philip Orlik, Toshiaki Koike-Akino, Jianlin Guo
  • Publication number: 20200174194
    Abstract: A grating coupler having first and second ends for coupling a light beam to a waveguide of a chip includes a substrate configured to receive the light beam from the first end and transmit the light beam through the second end, the substrate having a first refractive index n1, a grating structure having curved grating lines arranged on the substrate, the grating structure having a second refractive index n1, wherein the curved grating lines have line width w and height d and are arranged by a pitch ?, wherein the second refractive index n2 is less than first refractive index n1, and a cladding layer configured to cover the grating structure, wherein the cladding layer has a third refractive index n3.
    Type: Application
    Filed: January 29, 2019
    Publication date: June 4, 2020
    Inventors: Keisuke Kojima, Mitsunobu Gotoda, Toshiaki Koike-Akino, Mohammad Tahersima
  • Publication number: 20200081188
    Abstract: A photonic device for splitting optical beams includes an input port configured to receive an input beam having an input power, a power splitter including perturbation segments arranged in a first region and a second region of a guide material having a first refractive index, each segment having a second refractive index, wherein the first region is configured to split the input beam into a first beam and a second beam, wherein and the second region is configured to separately guide the first and second beams, wherein the first refractive index is greater than the second refractive index, and output ports including first and second output ports connected the power splitter to respectively receive and transmit the first and second beams.
    Type: Application
    Filed: December 10, 2018
    Publication date: March 12, 2020
    Applicant: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Keisuke Kojima, Mohammad hossein Taher sima, Toshiaki Koike-Akino
  • Patent number: 10554309
    Abstract: A method decodes an optical signal transmitted over an optical channel from a transmitter to a receiver. The method produces, from the transmitted optical signal, a digital signal including received data symbols and received pilot symbols and determines phase noise on the pilot symbols using a statistical probability distribution of phase noise on the optical channel and errors between phases of the received pilot symbols and the transmitted pilot signals. The method estimates phase noise on the data symbols using an interpolation of the phase noise on the pilot symbols and compensates the digital signal with the phase noise on the data symbols to produce a filtered signal with an equalized phase. The method demodulates and decodes the filtered signal to produce an estimate of the transmitted optical signal.
    Type: Grant
    Filed: January 18, 2018
    Date of Patent: February 4, 2020
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: David Millar, Milutin Pajovic, Toshiaki Koike-Akino, Keisuke Kojima, Kieran Parsons
  • Patent number: 10541711
    Abstract: A communication system transmits an input block of bits over a communication channel using a prefix tree that maps a dyadic distribution of compositions of output symbols to prefixes of variable lengths. A path to each leaf of the prefix tree is defined by a prefix formed by a unique sequence of binary values of a length equal to a depth of the leaf. Each leaf is associated with a composition that has at least a number of unique permutations equals to two in a power of a length of a suffix of the block of input bits. The system selects a composition identified in the prefix tree by a prefix in the input block of bits, permutes the selected composition according to a suffix in the input block of bits, and transmits the permuted composition over a communication channel.
    Type: Grant
    Filed: March 29, 2019
    Date of Patent: January 21, 2020
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: David Millar, Tobias Fehenberger, Toshiaki Koike-Akino, Keisuke Kojima, Kieran Parsons
  • Patent number: 10516503
    Abstract: A communication system includes a data source to receive a block of bits, a processor, a memory, in connection with the processor, to store a distribution matcher associated with a probability mass function (PMF) configured to match a block of equally likely input bits to a fixed number of output bits with values distributed according to the PMF of the distribution matcher using the processor. In this case, the distribution matcher contains a set of parallel binary distribution matchers which specify fully a target PMF, and a transmitter front end to transmit a block of shaped bits over a communication channel, such that bits in a sequence of the blocks of shaped bits are distributed according to the target PMF.
    Type: Grant
    Filed: February 20, 2019
    Date of Patent: December 24, 2019
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: David Millar, Tobias Fehenberger, Toshiaki Koike-Akino, Kieran Parsons, Keisuke Kojima
  • Publication number: 20190339584
    Abstract: An optical ring circuit for modulating light from a light source into an optical signal includes a ring modulator located near a waveguide to couple a light propagating the waveguide, the ring modulator including a pair of electrodes, a signal generator to transmit an electrical signal corresponding to the optical signal, a filter circuit to generate an output signal, wherein the filter circuit includes an adder unit and at least one tap unit having a delay unit and a coefficient unit, wherein the adder unit adds the electrical signal from the signal generator and a signal passed from the tap unit for pre-compensating signal components of the electrical signal by at least twice delay time of the delay unit, and a driver circuit to apply a voltage to the electrodes based on the output signal.
    Type: Application
    Filed: September 7, 2018
    Publication date: November 7, 2019
    Inventors: Keisuke Kojima, Min Teng, Toshiaki Koike-Akino, Chungwei Lin, Kieran Parsons, Mitsunobu Gotoda, Koichi Akiyama
  • Patent number: 10455250
    Abstract: A method for reconstructing an uncompressed signal. The method includes obtaining an encoded signal corresponding to the signal. Obtaining side information about the signal and using the side information to obtain a prediction of dithered linear measurements of the signal. Using the prediction of the dithered linear measurements and encoded quantized dithered linear measurements to obtain quantized linear measurements of the signal based on processing each bitplane iteratively, starting from a least significant level bitplane to a most significant level bitplane. At each iteration, a prediction of each bitplane is formed using the prediction of the dithered linear measurements and the bitplanes processed in the previous iterations. Wherein each code for each bitplane is used to correct each bitplane prediction. Reconstructing the signal as a reconstructed signal using the recovered quantized dithered linear measurements, wherein the steps are performed in a processor of a decoder.
    Type: Grant
    Filed: May 30, 2017
    Date of Patent: October 22, 2019
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Petros Boufounos, Maxim Goukhshtein, Toshiaki Koike-Akino, Stark C Draper
  • Publication number: 20190317315
    Abstract: An encoder of a terahertz (THz)-based absolute positioning system used for decoding patterns from THz-band measurements. The encoder includes a scale with a multi-layer reflective/transmissive structure having a matrix with rows. Each row of the matrix corresponds to a plurality of patterns, such that each pattern is used to form a measurement. An emitter emits a THz waveform to the scale. A receiver is used to measure amplitudes of the THz waveform reflected from the scale. A memory stores data including predetermined positions of the emitter based on the patterns of the layers from the scale. Wherein one or more processors can determine a position of the emitter from the measurements of the amplitudes received by the receiver, based on the stored data. An output interface can be used to render the position of the emitter.
    Type: Application
    Filed: April 12, 2018
    Publication date: October 17, 2019
    Inventors: Pu Wang, Haoyu Fu, Philip Orlik, Toshiaki Koike-Akino, Rui Ma, Bingnan Wang
  • Patent number: 10425910
    Abstract: A millimeter-wave (mmWave) communication system for determining a location of a first device based on a known location of a second device includes a transceiver connected to a set of antennas to communicate beams of mmWaves and to perform an estimation of a channel connecting the first device and the second device and a memory to store results of the channels estimation including pairs of beam values, wherein each pair of beam values includes a beamforming angle and an energy of the beam communicated with the beamforming angle.
    Type: Grant
    Filed: March 19, 2018
    Date of Patent: September 24, 2019
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Milutin Pajovic, Toshiaki Koike Akino, Philip Orlik