Patents by Inventor Norihiro Sakamoto

Norihiro Sakamoto 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: 20090052897
    Abstract: A station-side communication device connected to subscriber-side communication devices via an optical combining device; sending, to the subscriber-side communication devices, a distance measurement request signal; computing transmission delay times of optical signals from the individual subscriber-side communication devices by receiving distance measurement signals, and including: a threshold control part identifying the level of distance measurement signals; a signal detection part detecting breaks in the distance measurement signals from the threshold control part; a transmission granting part determining the timing at which transmission of optical signals is granted, and a reset timing generation part that, there is notification of detection of a break in the distance measurement signal from the signal detection part while it is being notified that distance measurement is carried out to and from the subscriber-side communication devices from the transmission granting part, sends a reset signal indicating t
    Type: Application
    Filed: October 20, 2008
    Publication date: February 26, 2009
    Applicant: HITACHI COMMUNICATION TECHNOLOGIES, LTD
    Inventors: Tohru KAZAWA, Masaki Ohira, Yusuke Yajima, Norihiro Sakamoto
  • Patent number: 7489869
    Abstract: A station-side communication device connected to subscriber-side communication devices via an optical combining device; sending, to the subscriber-side communication devices, a distance measurement request signal; computing transmission delay times of optical signals from the individual subscriber-side communication devices by receiving distance measurement signals, and including: a threshold control part identifying the level of distance measurement signals; a signal detection part detecting breaks in the distance measurement signals from the threshold control part; a transmission granting part determining the timing at which transmission of optical signals is granted, and a reset timing generation part that, there is notification of detection of a break in the distance measurement signal from the signal detection part while it is being notified that distance measurement is carried out to and from the subscriber-side communication devices from the transmission granting part, sends a reset signal indicating t
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: February 10, 2009
    Assignee: Hitachi Communication Technologies, Ltd.
    Inventors: Tohru Kazawa, Masaki Ohira, Yusuke Yajima, Norihiro Sakamoto
  • Publication number: 20090034973
    Abstract: In order to be able to moderate the inclination of the PON burst reception characteristics and to improve the FEC effect, a first offset is used in a ranging window field, and a second offset, which is lower than the first offset value, is used in a burst data field other than the ranging window field.
    Type: Application
    Filed: January 30, 2008
    Publication date: February 5, 2009
    Inventors: Norihiro SAKAMOTO, Yusuke Yajima, Tohru Kazawa
  • Publication number: 20080317469
    Abstract: A station-side communication device connected to subscriber-side communication devices via an optical combining device; sending, to the subscriber-side communication devices, a distance measurement request signal; computing transmission delay times of optical signals from the individual subscriber-side communication devices by receiving distance measurement signals, and including: a threshold control part identifying the level of distance measurement signals; a signal detection part detecting breaks in the distance measurement signals from the threshold control part; a transmission granting part determining the timing at which transmission of optical signals is granted, and a reset timing generation part that, there is notification of detection of a break in the distance measurement signal from the signal detection part while it is being notified that distance measurement is carried out to and from the subscriber-side communication devices from the transmission granting part, sends a reset signal indicating t
    Type: Application
    Filed: August 4, 2008
    Publication date: December 25, 2008
    Applicant: Hitachi Communication Technologies, Ltd.
    Inventors: Tohru Kazawa, Masaki Ohira, Yusuke Yajima, Norihiro Sakamoto
  • Publication number: 20080155255
    Abstract: There is provided an encryption apparatus including an idle data inserting unit that takes input of a frame including a fixed-length header and a variable-length payload and an encrypting unit that receives an output of the idle data inserting unit. If the length of a block to be processed, included in the payload, is less than a predetermined value, the idle data inserting unit appends idle data following the block and transmits the frame including the block padded with the idle data to the encrypting unit.
    Type: Application
    Filed: August 31, 2007
    Publication date: June 26, 2008
    Inventors: Masaki Ohira, Norihiro Sakamoto
  • Publication number: 20080089686
    Abstract: A station-side communication device connected to subscriber-side communication devices via an optical combining device; sending, to the subscriber-side communication devices, a distance measurement request signal; computing transmission delay times of optical signals from the individual subscriber-side communication devices by receiving distance measurement signals, and including: a threshold control part identifying the level of distance measurement signals; a signal detection part detecting breaks in the distance measurement signals from the threshold control part; a transmission granting part determining the timing at which transmission of optical signals is granted, and a reset timing generation part that, there is notification of detection of a break in the distance measurement signal from the signal detection part while it is being notified that distance measurement is carried out to and from the subscriber-side communication devices from the transmission granting part, sends a reset signal indicating t
    Type: Application
    Filed: March 30, 2007
    Publication date: April 17, 2008
    Inventors: Tohru Kazawa, Masaki Ohira, Yusuke Yajima, Norihiro Sakamoto
  • Publication number: 20070064731
    Abstract: A transmission apparatus for use in fixed bandwidth communications and variable bandwidth communications. The transmission apparatus has a memory unit, which stores information contained in a frame and indicating the amount of data to be transmitted from a terminal device, a computing unit, which calculates a bandwidth amount to be assigned to the terminal device based on the data amount, and a transmission unit, which sends the calculated assigned bandwidth amount to the terminal device. The transmission apparatus is characterized in that the computing unit calculates bandwidth amounts to be assigned to different types of flow of which different transmission qualities are requested according to a priority level that is set to each flow type. The transmission apparatus is also characterized in that bandwidth is controlled by designating, instead of a necessary bandwidth amount, transmission starting timing and transmission ending timing, particularly for fixed bandwidth communication data.
    Type: Application
    Filed: January 27, 2006
    Publication date: March 22, 2007
    Inventors: Masahiko Mizutani, Yoshihiro Ashi, Masayuki Takase, Kenichi Sakamoto, Atsushi Iwamura, Tohru Kazawa, Norihiro Sakamoto
  • Patent number: 6140631
    Abstract: A first object of the present invention is to provide a photosensor for use in an apparatus such as a copying machine, a printer etc. employing an electrophotographic technology which can prevent an image anomaly such as a blurring from generation even if it is exposed to a high-humidity ambient for a long period and subjected to multiple repetitions of numerous printing characters.A second object of the invention is to provide a photosensor for use in electrophotography which is excellent in surface abrasion durability, humidity resistivity etc.To satisfy the first purpose mentioned above, a photoconductive layer 2 formed of an amorphous layer including silicon atoms as a major element is deposited on a conductive substrate 1 formed of aluminium etc.
    Type: Grant
    Filed: August 20, 1998
    Date of Patent: October 31, 2000
    Assignee: Stanley Electric Co., Ltd.
    Inventors: Hiroaki Hamanaka, Norihiro Sakamoto, Fumiyuki Suda