Patents by Inventor Masahiro Kumagawa

Masahiro Kumagawa 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: 10769917
    Abstract: A wireless communications system according to an aspect includes a communications terminal, a detection unit, and a control unit. The communications terminal includes a communications unit to communicate wirelessly with a communications partner terminal. The detection unit detects movement of the communications terminal. The control unit controls the communications terminal so as to vary a communicable area of the communications unit. The communicable area is defined relatively to the communications terminal. The control unit varies the communicable area according to at least magnitude of the movement detected by the detection unit.
    Type: Grant
    Filed: April 17, 2019
    Date of Patent: September 8, 2020
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Koji Imamura, Shinichi Okada, Motoo Nakagawa, Masahiro Kumagawa, Junichi Takahashi
  • Publication number: 20200242580
    Abstract: A shopping assistance system includes a strength acquirer and a determining processor. The strength acquirer is configured to acquire values of a received signal strength indication at a reader device while the reader device performs wireless communication with an electronic tag attached to at least one product. The reader device is configured to perform the wireless communication with the electronic tag by using a radio wave as a medium to read a piece of product information on the at least one product. The determining processor is configured to determine, for each of the at least one product, whether or not the at least one product is an object to be purchased based on a change of the received signal strength indication over time.
    Type: Application
    Filed: September 26, 2018
    Publication date: July 30, 2020
    Inventors: Koji IMAMURA, Junichi TAKAHASHI, Masahiro KUMAGAWA, Motoo NAKAGAWA, Shinichi OKADA
  • Publication number: 20190362109
    Abstract: An information acquisition system includes an inner wall, an outer wall, and an antenna. The inner wall includes a reflective layer which reflects a radio wave. A reading space is located on an inner side of the reflective layer. Reading of tag information from an RF tag attached to an item is performed in the reading space. The outer wall is disposed on an opposite side of the inner wall from the reading space. The antenna is configured to output the radio wave toward the reading space in order to communicate with the RF tag. Between the inner wall and the outer wall, a peripheral space is provided. The reflective layer of the inner wall has a hole. The hole penetrates through the reflective layer in a thickness direction of the reflective layer.
    Type: Application
    Filed: May 21, 2019
    Publication date: November 28, 2019
    Inventors: Suguru KOJIMA, Shinichi OKADA, Masahiro KUMAGAWA, Masahiro NAKANO
  • Publication number: 20190325723
    Abstract: A wireless communications system according to an aspect includes a communications terminal, a detection unit, and a control unit. The communications terminal includes a communications unit to communicate wirelessly with a communications partner terminal. The detection unit detects movement of the communications terminal. The control unit controls the communications terminal so as to vary a communicable area of the communications unit. The communicable area is defined relatively to the communications terminal. The control unit varies the communicable area according to at least magnitude of the movement detected by the detection unit.
    Type: Application
    Filed: April 17, 2019
    Publication date: October 24, 2019
    Inventors: Koji IMAMURA, Shinichi OKADA, Motoo NAKAGAWA, Masahiro KUMAGAWA, Junichi TAKAHASHI
  • Publication number: 20190213572
    Abstract: A wireless reading system includes a goods path and a reader device. The goods path allows one or more goods held by a customer passing through a customer path to be moved along. The reader device is configured to perform wireless communication, whose medium is radio waves, with one or more electronic tags attached to the one or more goods while the one or more goods are moved along the goods path, thereby reading one or more pieces of goods information on the one or more goods, respectively.
    Type: Application
    Filed: December 28, 2018
    Publication date: July 11, 2019
    Inventors: Koji IMAMURA, Atsushi MARUYAMA, Shinichi OKADA, Motoo NAKAGAWA, Masahiro KUMAGAWA, Shinsuke OGATA
  • Patent number: 9479127
    Abstract: A power amplification apparatus generates a code for controlling the number of class D power amplifiers that are in operation among a plurality of class D power amplifiers, changes the duty ratio of a carrier wave signal in accordance with output voltage, and amplifies a transmission signal. A code for decreasing the number of class D power amplifiers in operation is generated when the duty ratio of the carrier wave signal is increased, while a code for increasing the number of class D power amplifiers in operation is generated when the duty ratio of the carrier wave signal is decreased.
    Type: Grant
    Filed: February 19, 2015
    Date of Patent: October 25, 2016
    Assignee: PANASONIC CORPORATION
    Inventors: Masahiro Kumagawa, Hisashi Adachi
  • Patent number: 9331635
    Abstract: A quadrature modulator includes a first switched capacitor power amplifier that amplifies a first high-frequency signal, a second switched capacitor power amplifier that amplifies a second high-frequency signal, a first combiner which includes at least one pair of winding wires, one winding wire in one pair being disposed on a primary side to which the amplified first high-frequency signal and the amplified second high-frequency signal are separately input and the other winding wire in the one pair being disposed on a secondary side, the first combiner combining the input amplified first high-frequency signal and the input amplified second high-frequency signal to generate a quadrature modulation signal from the secondary side, a first inductor disposed between the first switched capacitor power amplifier and the primary side of the first combiner, and a second inductor disposed between the second switched capacitor power amplifier and the primary side of the first combiner.
    Type: Grant
    Filed: March 18, 2015
    Date of Patent: May 3, 2016
    Assignee: Panasonic Corporation
    Inventors: Masahiro Kumagawa, Yoshito Hirai
  • Patent number: 9240812
    Abstract: A power amplification device includes: a first power-amplifier array including a plurality of first switching elements that constitute a class-D power amplifier for a higher bits; a second power-amplifier array including a plurality of second switching elements that constitute a class-D power amplifier for a lower bits; and a capacitor array including a plurality of capacitance elements. The second switching elements have a larger on-resistance than the first switching elements. The first power-amplifier array is arranged between the second power-amplifier array and the capacitor array.
    Type: Grant
    Filed: February 19, 2015
    Date of Patent: January 19, 2016
    Assignee: PANASONIC CORPORATION
    Inventors: Masahiro Kumagawa, Akinori Daimo, Hisashi Adachi
  • Patent number: 9209750
    Abstract: A harmonic rejection mixer is disclosed that is capable of supporting wideband reception without any increase in circuit area. In this apparatus, transistors convert an RF signal to currents. Transistors perform frequency conversion based on the currents from the transistors and local oscillation signals. Transistors distribute the currents from the transistors to all transistors or some transistors based on a predetermined ratio. A load adds up the currents from the transistors and converts the resultant current to a voltage.
    Type: Grant
    Filed: December 25, 2013
    Date of Patent: December 8, 2015
    Assignee: PANASONIC CORPORATION
    Inventors: Masahiro Kumagawa, Yuusuke Yamaoka
  • Patent number: 9148089
    Abstract: A transmitting apparatus and transmission method are capable of easily and correctly mixing an in-phase component and a quadrature-phase component in a quadrature modulator. A local signal with a duty ratio of 25% or smaller is generated without using frequency which is a multiple of frequency of the local signal. Without providing switches in series to the outputs of I and Q amplifiers, a duty ratio of 25% or less is obtained. for the local signal, and class-D unit amplifiers are operated such that one of the I amplifier and the Q amplifier is connected to the output side in any state regardless of whether an output power control signal is at an on-level or an off-level. In producing the 25% duty ratio, a local signal with a 50% duty ratio is converted so as to have a duty ratio of 25% by I and Q duty converters.
    Type: Grant
    Filed: November 17, 2014
    Date of Patent: September 29, 2015
    Assignee: Panasonic Corporation
    Inventors: Masakatsu Maeda, Masahiro Kumagawa, Hisashi Adachi, Akinori Daimo, Kenichi Mori
  • Publication number: 20150249431
    Abstract: A power amplification apparatus generates a code for controlling the number of class D power amplifiers that are in operation among a plurality of class D power amplifiers, changes the duty ratio of a carrier wave signal in accordance with output voltage, and amplifies a transmission signal. A code for decreasing the number of class D power amplifiers in operation is generated when the duty ratio of the carrier wave signal is increased, while a code for increasing the number of class D power amplifiers in operation is generated when the duty ratio of the carrier wave signal is decreased.
    Type: Application
    Filed: February 19, 2015
    Publication date: September 3, 2015
    Inventors: MASAHIRO KUMAGAWA, HISASHI ADACHI
  • Publication number: 20150244324
    Abstract: A power amplification device includes: a first power-amplifier array including a plurality of first switching elements that constitute a class-D power amplifier for a higher bits; a second power-amplifier array including a plurality of second switching elements that constitute a class-D power amplifier for a lower bits; and a capacitor array including a plurality of capacitance elements. The second switching elements have a larger on-resistance than the first switching elements. The first power-amplifier array is arranged between the second power-amplifier array and the capacitor array.
    Type: Application
    Filed: February 19, 2015
    Publication date: August 27, 2015
    Inventors: MASAHIRO KUMAGAWA, AKINORI DAIMO, HISASHI ADACHI
  • Patent number: 9112482
    Abstract: A received is disclosed that is capable of improving reception sensitivity while avoiding an increase in circuit scale. The receiver includes: a multi-phase local oscillation signal generating section that generates a plurality of local oscillation signals of different phases; a phase selection signal generating section that generates a phase selection signal used to select a baseband signal of a predetermined phase based on a detection result of a reception level of a high-frequency signal; and a frequency converter that frequency-converts the high-frequency signal based on the plurality of local oscillation signals, that generates a plurality of baseband signals of different phases, and that selects a baseband signal from among the plurality of baseband signals based on the phase selection signal.
    Type: Grant
    Filed: December 25, 2013
    Date of Patent: August 18, 2015
    Assignee: Panasonic Corporation
    Inventors: Masahiro Kumagawa, Yoshifumi Hosokawa
  • Publication number: 20150194934
    Abstract: A quadrature modulator includes a first switched capacitor power amplifier that amplifies a first high-frequency signal having a first phase, a second switched capacitor power amplifier that amplifies a second high-frequency signal having a second phase different from the first phase, a first combiner which includes at least one pair of winding wires that are magnetically coupled to each other, one winding wire in one pair being disposed on a primary side to which the amplified first high-frequency signal and the amplified second high-frequency signal are separately input and the other winding wire in the one pair being disposed on a secondary side, the first combiner combining the input amplified first high-frequency signal and the input amplified second high-frequency signal to generate a quadrature modulation signal from the secondary side, a first inductor disposed between the first switched capacitor power amplifier and the primary side of the first combiner, and a second inductor disposed between the se
    Type: Application
    Filed: March 18, 2015
    Publication date: July 9, 2015
    Inventors: MASAHIRO KUMAGAWA, YOSHITO HIRAI
  • Publication number: 20150180418
    Abstract: A transmitting apparatus and transmission method are capable of easily and correctly mixing an in-phase component and a quadrature-phase component in a quadrature modulator. A local signal with a duty ratio of 25% or smaller is generated without using frequency which is a multiple of frequency of the local signal. Without providing switches in series to the outputs of I and Q amplifiers, a duty ratio of 25% or less is obtained. for the local signal, and class-D unit amplifiers are operated such that one of the I amplifier and the Q amplifier is connected to the output side in any state regardless of whether an output power control signal is at an on-level or an off-level. In producing the 25% duty ratio, a local signal with a 50% duty ratio is converted so as to have a duty ratio of 25% by I and Q duty converters.
    Type: Application
    Filed: November 17, 2014
    Publication date: June 25, 2015
    Inventors: MASAKATSU MAEDA, MASAHIRO KUMAGAWA, HISASHI ADACHI, AKINORI DAIMO, KENICHI MORI
  • Publication number: 20150084683
    Abstract: A harmonic rejection mixer is disclosed that is capable of supporting wideband reception without any increase in circuit area. In this apparatus, transistors convert an RF signal to currents. Transistors perform frequency conversion based on the currents from the transistors and local oscillation signals. Transistors distribute the currents from the transistors to all transistors or some transistors based on a predetermined ratio. A load adds up the currents from the transistors and converts the resultant current to a voltage.
    Type: Application
    Filed: December 25, 2013
    Publication date: March 26, 2015
    Inventors: Masahiro Kumagawa, Yuusuke Yamaoka
  • Publication number: 20150070055
    Abstract: A received is disclosed that is capable of improving reception sensitivity while avoiding an increase in circuit scale. The receiver includes: a multi-phase local oscillation signal generating section that generates a plurality of local oscillation signals of different phases; a phase selection signal generating section that generates a phase selection signal used to select a baseband signal of a predetermined phase based on a detection result of a reception level of a high-frequency signal; and a frequency converter that frequency-converts the high-frequency signal based on the plurality of local oscillation signals, that generates a plurality of baseband signals of different phases, and that selects a baseband signal from among the plurality of baseband signals based on the phase selection signal.
    Type: Application
    Filed: December 25, 2013
    Publication date: March 12, 2015
    Inventors: Masahiro Kumagawa, Yoshifumi Hosokawa
  • Patent number: 7245890
    Abstract: A high frequency variable gain amplification device 100 includes: a feedback circuit 103 capable of changing a feedback impedance to adjust the gain of an amplifier 101 in accordance with a control signal from a control device 200; and a current consumption adjustment circuit 102 capable of adjusting current consumption of the amplifier 101. The control device 200 controls the feedback impedance and the current consumption based on a desired signal power level and an undesired signal power level. If the desired signal power level exceeds a predetermined value, the control device 200 reduces the feedback impedance to increase the amount of a feedback signal, thereby allowing the amplifier 101 to operate with low gain so as to prevent the distortion characteristic from being reduced and to reduce the current consumption.
    Type: Grant
    Filed: July 21, 2004
    Date of Patent: July 17, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masahiro Kumagawa, Toshifumi Nakatani, Hisashi Adachi
  • Publication number: 20050020227
    Abstract: A high frequency variable gain amplification device 100 includes: a feedback circuit 103 capable of changing a feedback impedance to adjust the gain of an amplifier 101 in accordance with a control signal from a control device 200; and a current consumption adjustment circuit 102 capable of adjusting current consumption of the amplifier 101. The control device 200 controls the feedback impedance and the current consumption based on a desired signal power level and an undesired signal power level. If the desired signal power level exceeds a predetermined value, the control device 200 reduces the feedback impedance to increase the amount of a feedback signal, thereby allowing the amplifier 101 to operate with low gain so as to prevent the distortion characteristic from being reduced and to reduce the current consumption.
    Type: Application
    Filed: July 21, 2004
    Publication date: January 27, 2005
    Inventors: Masahiro Kumagawa, Toshifumi Nakatani, Hisashi Adachi