Patents by Inventor Yasunao Katayama

Yasunao Katayama 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).

  • Publication number: 20120320786
    Abstract: A method for fast and efficient data downloading in wireless communications. The method includes ways to download file data of a large size from a server (access point) to a user's client (mobile device) at high speed and efficiency by using both mmWave wireless communication and conventional wireless communication (WiFi, 3G, etc.). A server transmits packetized file data to a client. The file data is transmitted as data packets via mmWave. In parallel, the server transmits check packets (roll-call packets) corresponding to the data packets. As a test at the time of establishing links, the latency for each communication line is measured. The receiver side, upon completion of receiving the check packets, checks whether their corresponding mmWave packets have arrived. If any corresponding mmWave packet has not arrived, it is determined that the mmWave packet has been lost and a retransmission request is immediately returned to the server via WiFi.
    Type: Application
    Filed: August 30, 2012
    Publication date: December 20, 2012
    Applicant: International Business Machines Corporation
    Inventors: Yasunao Katayama, Nobuyuki Ohba, Kohji Takano
  • Patent number: 8289087
    Abstract: A computer-implemented method, device, and program product for detecting a phase shift between an I data clock and a Q data clock in processing an I data signal or a Q data signal used in quadrature modulation or quadrature demodulation. The method includes: receiving an input of the I data clock and the Q data clock; performing exclusive-ORing (XORing) on the I data clock and the Q data clock; latching a result of the performance of XORing on a phase sampling clock which is asynchronous with the I data clock and the Q data clock; incrementing a first number; incrementing a second number; comparing the incremented first number and the incremented second number and determining, based on a phase determination criterion, a phase shift between the I data clock and the Q data clock; and detecting a phase shift between the I data clock and the Q data clock.
    Type: Grant
    Filed: September 15, 2010
    Date of Patent: October 16, 2012
    Assignee: International Business Machines Corporation
    Inventors: Yasunao Katayama, Yasuteru Kohda, Nobuyuki Ohba
  • Publication number: 20120210167
    Abstract: A method for fast and efficient data downloading in wireless communications. The method includes ways to download file data of a large size from a server (access point) to a user's client (mobile device) at high speed and efficiency by using both mmWave wireless communication and conventional wireless communication (WiFi, 3G, etc.). A server transmits packetized file data to a client. The file data is transmitted as data packets via mmWave. In parallel, the server transmits check packets (roll-call packets) corresponding to the data packets. As a test at the time of establishing links, the latency for each communication line is measured. The receiver side, upon completion of receiving the check packets, checks whether their corresponding mmWave packets have arrived. If any corresponding mmWave packet has not arrived, it is determined that the mmWave packet has been lost and a retransmission request is immediately returned to the server via WiFi.
    Type: Application
    Filed: February 13, 2012
    Publication date: August 16, 2012
    Applicant: International Business Machines Corporation
    Inventors: Yasunao Katayama, Nobuyuki Ohba, Kohji Takano
  • Patent number: 8233622
    Abstract: Synchronized pseudo-random number outputs are produced at a transmitter and a receiver of a high-speed serial interconnection. At the transmitter, using logic XOR operations, each data word of parallel data is selectively scrambled with one of the pseudo-random numbers and transmitted via a high-speed serial interface. The receiver de-scrambles the received serial data stream and restores the parallel data.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: July 31, 2012
    Assignee: International Business Machines Corporation
    Inventors: Atsuya Okazaki, Yasunao Katayama
  • Publication number: 20120143936
    Abstract: A system and method to reduce roundoff error of Fast Fourier transform (FFT) operation. Data which comes out as an irrational number (a square root) out of twiddle factors on a complex plane, included in a butterfly operation (8p) is preserved intentionally without being calculated in one stage of multiple stages of a multi-stage pipelined FFT, and when it occurs again in a later stage, an operation to multiply the two twiddle factors with each other is performed. This enables to eliminate roundoff errors during the butterfly operation 8p of radix-8. Other applications are also possible such as by overlaying a further stage by a butterfly operation of radix-2 or radix-4.
    Type: Application
    Filed: November 21, 2011
    Publication date: June 7, 2012
    Applicant: International Business Machines Corporation
    Inventors: Yasunao Katayama, Kohji Takano
  • Publication number: 20120027354
    Abstract: A backplane, a method for making a backplane, and optical communication apparatuses. The backplane includes: a plurality of optical elements each selected from the group consisting of: (i) optical fibers, (ii) optical waveguides, and (iii) a combination thereof, where the plurality of optical elements have the same length, where the plurality of optical elements form at least one bundle, where the elements are bundled at both ends of the at least one bundle such that end portion lengths of the plurality of optical elements differ from each other, thus forming a broadcast-star topology, and where the plurality of optical elements is connected such that communication distance between at least two blades that can be inserted into the back plane is constant.
    Type: Application
    Filed: June 28, 2011
    Publication date: February 2, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yasunao Katayama, Seiji Munetoh, Atsuya Okazaki
  • Patent number: 8037395
    Abstract: A Partially-Overlapped Block (POB) code used in an encoding and decoding method in which a plurality of different block codes are combined so that the block codes partially overlap one another. A method for recovering a plurality of packets by using a loss correction capability of this encoding method in which a larger number of packets than the number of added redundant packets per frame are recovered, by reusing redundant information of neighboring frames effectively, without increasing the asymptotic complexity of its decoding algorithm.
    Type: Grant
    Filed: July 3, 2007
    Date of Patent: October 11, 2011
    Assignee: International Business Machines Corporation
    Inventors: Yasunao Katayama, Daiju Nakano
  • Patent number: 8005161
    Abstract: A method, a hardware product, and a computer program product for performing high data rate wireless transmission and reception. Minimum shift-keyed (MSK) data is transmitted by multiplexing a first MSK data stream and a second MSK data stream wherein the first MSK data stream is substantially 90-degree phase-shifted with respect to the second MSK data stream. The transmitted MSK data is received by performing phase recovery and demodulation using an FM discriminator having a demodulation circuit for implementing a 45-degree phase shift prior to demodulation.
    Type: Grant
    Filed: May 1, 2008
    Date of Patent: August 23, 2011
    Assignee: International Business Machines Corporation
    Inventors: Yasunao Katayama, Daiju Nakano
  • Publication number: 20110150151
    Abstract: A method and circuitry for detecting a frequency offset (?) between data at a transmission symbol rate (fTx) transmitted from a transmitter and a reception sampling frequency (fRx) operating in a receiver on the basis of hard decision based on a binary number in the receiver. The receiver uses a converter to make binary hard decisions performs n times oversampling, then obtains a symbol decision value, calculates a timing correlation value for each plurality of partition phases, and calculates a cumulative timing correlation value for a specific period or number of additions. The receiver determines whether its sampling frequency is higher or lower than a correct symbol rate, appropriately shifts a sampling position, and makes reception while maintaining the correct sampling position thereby enables data deviation caused by a frequency offset to be compensated on the fly.
    Type: Application
    Filed: December 21, 2010
    Publication date: June 23, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yasunao Katayama, Daiju Nakano
  • Publication number: 20110145675
    Abstract: One or more embodiments provide a decoding technique (and its approximate decoding technique) enabling a stable operation even if a noise variance is low at the implementation with a fixed-point arithmetic operation having a finite dynamic range. A technique is provided for causing a computer to perform calculation using a sum-product decoding method (belief propagation method) with respect to LDPC or turbo codes. For calculating an update equation of a log extrinsic value ratio from an input, a (separated) correction term is prepared obtained by variable transformation (scale transformation) of the update equation so that the update equation is represented by a sum (combination) of a plurality of terms by transformation of the equation and a communication channel noise variance is a term separated from other terms constituting a sum of a plurality of terms as a term to be a factor (scale factor) by which a log is multiplied.
    Type: Application
    Filed: December 14, 2010
    Publication date: June 16, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yasunao Katayama, Toshiyuki Yamane
  • Patent number: 7956348
    Abstract: A quantum device comprises first conductive members and second conductive members confining carriers in the z direction and having two dimensional electron gas on the xy plane. Third conductive members generating an electric field having an effect on the first conductive members. An insulating member easily passing a tunnel current between the first conductive members and the second conductive members. Another insulating member hardly passing a tunnel current between the first conductive members and the third conductive members. An electric field generated by a potential applied to the third conductive members has an effect on the sub-band of the first conductive members.
    Type: Grant
    Filed: May 26, 2005
    Date of Patent: June 7, 2011
    Assignee: International Business Machines Corporation
    Inventor: Yasunao Katayama
  • Publication number: 20110130108
    Abstract: A radio receiver including a sampling unit, a provider, an arithmetic operation unit, an estimator, and a converter. The sampling unit samples a baseband signal transmitted from the radio transmitter, at a fractional multiple of a symbol rate, and generates fractional-multiple-sampling data. The provider provides reference data in which the known symbol sequence arranged in a frame by the radio transmitter is interpolated at a rate of the fractional multiple. The arithmetic operation unit performs an arithmetic operation for evaluation data in which the degree of consistency in waveform between the fractional-multiple-sampling data and the reference data is evaluated. The estimator estimates a reference timing from a shift amount at which the evaluation data shows the maximum degree of consistency in waveform. The converter converts the fractional-multiple-sampling data by using the reference timing as a reference thereby recovering the data having the symbol rate.
    Type: Application
    Filed: November 17, 2010
    Publication date: June 2, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yasunao Katayama, Daiju Nakano
  • Publication number: 20110128912
    Abstract: A system including multiple nodes performing radio communication, wherein each node stores routing information, uses it to determine a transmission path, and performs cut-through transmission by transmitting and receiving packets to and from a node on the determined path through transmission and reception radio waves given a directivity by controlling their phases. In the system, time synchronization and transmission and reception of packet communication records are performed during a certain time period by carrying out the cut-through transmission while controlling phases of the radio waves so that all of the nodes form one or more closed loops. The node transmits and receives packets in accordance with routing information and a time frame assigned to each of the nodes as a time when each node is allowed to transmit and receive a packet, updates the routing information, and shares it with each node.
    Type: Application
    Filed: November 22, 2010
    Publication date: June 2, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yasunao Katayama, Yasushi Negishi, Atsuya Okazaki
  • Publication number: 20110075776
    Abstract: A method and circuit that gives a sequence pattern that represents directions of positive and negative transitions of the phase that continue over a predetermined number from a certain reference symbol to an adjoining next reference symbol; finds (heuristically) one or more interpolate symbols that meet conditions (such as standards for power spectra) of a predetermined frequency spectrum, i.e., band, and a predetermined (range of) amplitude with reference to the given sequence pattern; and stores the found sequence pattern and a phase value and an amplitude value corresponding to the found one or more interpolate symbols in a memory as a lookup table against the prepared memory area.
    Type: Application
    Filed: September 29, 2010
    Publication date: March 31, 2011
    Applicant: International Business Machines Corporation
    Inventors: Yasunao Katayama, Daiju Nakano, Kohji Takano
  • Publication number: 20110063150
    Abstract: A computer-implemented method, device, and program product for detecting a phase shift between an I data clock and a Q data clock in processing an I data signal or a Q data signal used in quadrature modulation or quadrature demodulation. The method includes: receiving an input of the I data clock and the Q data clock; performing exclusive-ORing (XORing) on the I data clock and the Q data clock; latching a result of the performance of XORing on a phase sampling clock which is asynchronous with the I data clock and the Q data clock; incrementing a first number; incrementing a second number; comparing the incremented first number and the incremented second number and determining, based on a phase determination criterion, a phase shift between the I data clock and the Q data clock; and detecting a phase shift between the I data clock and the Q data clock.
    Type: Application
    Filed: September 15, 2010
    Publication date: March 17, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yasunao Katayama, Yasuteru Kohda, Nobuyuki Ohba
  • Publication number: 20100272439
    Abstract: A system and method for handling accesses by nodes connected to a ring network, using time division multiplexing (TDM). The system includes: nodes capable of receiving only an optical signal of a wavelength or positional space allocated to the node, and of transmitting optical signals of wavelengths allocated to other nodes; and a ring network that performs TDM transmission of optical signals. The ring network has slots for transmitting optical signals of individual wavelengths. Information indicates whether an optical signal to be transmitted exists in each of the slots. Nodes include means for updating the information indicating that the optical signal exists and determining means for updating the information and determining, on the basis of the information, whether to transmit the optical signal.
    Type: Application
    Filed: April 21, 2010
    Publication date: October 28, 2010
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yasunao Katayama, Atsuya Okazaki
  • Publication number: 20090319706
    Abstract: Synchronized pseudo-random number outputs are produced at a transmitter and a receiver of a high-speed serial interconnection. At the transmitter, using logic XOR operations, each data word of parallel data is selectively scrambled with one of the pseudo-random numbers and transmitted via a high-speed serial interface. The receiver de-scrambles the received serial data stream and restores the parallel data.
    Type: Application
    Filed: June 18, 2008
    Publication date: December 24, 2009
    Inventors: ATSUYA OKAZAKI, YASUNAO KATAYAMA
  • Publication number: 20090274221
    Abstract: A method, a hardware product, and a computer program product for performing high data rate wireless transmission and reception. Minimum shift-keyed (MSK) data is transmitted by multiplexing a first MSK data stream and a second MSK data stream wherein the first MSK data stream is substantially 90-degree phase-shifted with respect to the second MSK data stream. The transmitted MSK data is received by performing phase recovery and demodulation using an FM discriminator having a demodulation circuit for implementing a 45-degree phase shift prior to demodulation.
    Type: Application
    Filed: May 1, 2008
    Publication date: November 5, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yasunao Katayama, Daiju Nakano
  • Patent number: 7534710
    Abstract: The present invention relates to a device structure that contains two or more conducting layers, two peripheral insulating layers, one or more intermediate insulating layers, and two or more conductive contacts. The two or more conducting layers are sandwiched between the two peripheral insulating layers, and they are spaced apart by the intermediate insulating layers to form two or more quantum wells. Each of the conductive contacts is directly and selectively connected with one of the conducting layers, so the individual quantum wells can be selectively accessed through the conductive contacts. Such a device structure preferably contains a coupled quantum well devices having two or more quantum wells that can be coupled together by inter-well tunneling effect at degenerate energy levels. More preferably, the device structure contains a memory cell having three quantum wells that can be arranged and constructed to define two different memory states.
    Type: Grant
    Filed: December 22, 2005
    Date of Patent: May 19, 2009
    Assignee: International Business Machines Corporation
    Inventors: Yasunao Katayama, Dennis M. Newns, Chang C. Tsuei
  • Publication number: 20090125562
    Abstract: A method for monitoring memory integrity comprising, receiving a data read access request, updating a data read history register responsive to receiving a data read access request, the update comprising storing a first register value, wherein the first register value is defined by a previous register value and a first symmetric key encryption function, updating a data write history register in further response to receiving the data read access request, the update comprising storing a second register value, wherein the second register value is defined by a previous register value and a second symmetric key encryption function, receiving a data write access request, updating the data read history register responsive to receiving a data write access request, the update comprising storing the first register value, and updating the data write history register in further response to receiving the data write access request, the update comprising storing the second register value.
    Type: Application
    Filed: November 8, 2007
    Publication date: May 14, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yasunao Katayama, Atsuya Okazaki