Nippon Telegraph and Telephone Corporation

Mitsubishi Electric Corporation

Fujitsu Corporation

Ntt Electronics Corporation

Takuya Ohara

Masahito Tomizawa

Kei Kitamura

Etsushi Yamazaki

Fumikazu Inuzuka

Shigeki Aisawa

Yoshiaki Yamada

Yoshiaki Kisaka

Takayuki Mizuno

Akira Hirano

Hideki Maeda

Yohei Katayama

Kaoru Arai

Kazumitsu Sakamoto

Masahiro Yokota

Kento Yoshizawa

Kengo Shintaku

Takashi Kotanigawa

Takafumi Hamano

Takeshi Kinoshita

Mitsuru Mochizuki

Masayuki Nakazawa

Kuniyuki Suzuki

Takuya Oda

Taisei Suemitsu

Masahiro Suzuki

Daisuke Hiramatsu

Takafumi Tanaka

Masayuki Shimoda

Yutaka Miyamoto

Hidehiko Takara

Hiroyuki Fukumoto

Satoki Kawanishi

Tomoyoshi Kataoka

Tetsuo Takahashi

Koichi Ishihara

Takayuki Kobayashi

Masahiro Shioda

Ippei Shake

Kengo Horikoshi

Mitsuteru Yoshida

Mitsuhiro Teshima

Satoru Saitoh

Takashi Ono

Hiroyuki Honma

Kazuhito Takei

Kunihiko Mori

Masafumi Koga

Yasuyuki Endoh

Kohki Shibahara

Kenji Sato

Katsuyoshi Miura

Tadanobu Nikaido

When being connected to a macro cell (S-MeNB) and a small cell (SeNB), a user equipment device performs a pre-handover process of disconnecting the connection with the SeNB before a handover process of switching a macro cell connected with the UE from the macro cell (S-MeNB) that is a moving source to a macro cell (T-MeNB) that is a moving destination along with moving of the UE, and after the handover process, performs a post-handover process of reestablishing the connection with the SeNB.

Mobile communication system, base station, master base station, secondary base station and user equipment

One aspect of the present invention is an information processing system that includes a computing machine installed in a computing machine base, and a first transmitting/receiving apparatus connected to the computing machine, a second transmitting/receiving apparatus installed in a user base that is used by a user, and a device connected to the second transmitting/receiving apparatus, and a control apparatus configured to control connection between the first transmitting/receiving apparatus and the second transmitting/receiving apparatus. In the information processing system, the control apparatus is configured to change the connection between the first transmitting/receiving apparatus and the second transmitting/receiving apparatus, and copy the state of the pre-change computing machine from the pre-change computing machine into the post-change computing machine.

Information processing system, information processing method and program

One aspect of the present invention is an information processing system including a computer installed in a computer base, a first transceiver connected to the computer, a second transceiver installed in a user base used by a user, a device connected to the second transceiver, a network configured to perform communication between a plurality of the first transceivers and the second transceiver, and a controller configured to control connection between one of the plurality of the first transceivers and the second transceiver, in which the controller is configured to control connection between one of the plurality of the first transceivers and the second transceiver via the network having a circuit switching function.

A switching instructor outputs a beacon light selection notification signal when a optical transceiver transmits a optical wireless signal of a beacon light and outputs a signal light selection notification signal when the optical transceiver transmits the optical wireless signal of the signal light. A spatial light modulator controller performs switching of a control signal given to each of the plurality of pixels of a spatial light modulator to: cause a phase delay in light received by each of the plurality of pixels of the spatial light modulator when the switching instructor outputs the beacon light selection notification signal and cause a phase delay in light received by each of the plurality of pixels of the spatial light modulator when the switching instructor outputs the signal light selection notification signal.

Optical wireless communication device and optical wireless communication method

A communication device includes: a light output unit for outputting light; a light splitting unit for splitting the light output by the light output unit into a plurality of split beams; and a plurality of spatial optical communication units provided in correspondence to the plurality of split beams, wherein the spatial optical communication units respectively transmit a corresponding split beam which is input from the light splitting unit to a partner communication device across space.

Communication apparatus and optical communication system

A phase difference distribution estimation method includes: receiving an optical signal via a space and detecting a phase of the optical signal; calculating characteristic values related to characteristics of the atmosphere through which the optical signal propagates from the optical signal received in the receiving; estimating a phase difference distribution of an optical signal received after a certain period of time, on the basis of the characteristic values calculated in the calculating; and controlling a phase of an optical signal in the receiving on the basis of the phase difference distribution estimated in the estimating.

Phase difference distribution estimation method and phase difference distribution estimation apparatus

A transmission apparatus performs communication with a transmission side transmission apparatus via a transmission path of an active system and a transmission path of a standby system. The transmission apparatus includes: a memory configured to have a capacity that is as large as delay caused due to a maximum path difference between the transmission path of the active system and the transmission path of the standby system is allowable; and a memory connection control unit configured to switch connection of the memory and cause a signal of the transmission path of the active system or the transmission path of the standby system to be accumulated in the memory.

Transmission apparatus, transmission system and delay adjustment method

In an optical wireless communication system including: an optical wireless communication apparatus that moves along with a first optical wireless station; and a second optical wireless station opposed to the first optical wireless station, the optical wireless communication apparatus includes at least one reference light transmitting unit that transmits reference light to the second optical wireless station with a position in front in a moving direction of the first optical wireless station defined as a transmission position, the second optical wireless station includes a reference light receiving unit that receives the reference light transmitted from the at least one reference light transmitting unit, an estimation unit that estimates an influence of atmospheric air on transmission of signal light based on a reception state of the reference light received by the reference light receiving unit, a compensation unit that performs compensation processing on the signal light based on the influence of the atmospheric air estimated by the estimation unit, and a signal light transmitting unit that transmits the signal light on which the compensation processing has been performed by the compensation unit in an arrival direction of the reference light.

Optical wireless communication system and optical wireless communication method

Mobile communication system, master base station, secondary base station, target base station and user equipment

A first reception processing unit performs a process of receiving a first signal transmitted on a first transmission line, a second reception processing unit performs a process of receiving a second signal transmitted on a second transmission line, and an output speed control unit controls output speeds of the first signal and the second signal subjected to the reception process. A system switching unit selects and outputs the first signal or the second signal subjected to a reception process, and an output processing unit performs a process for output to another apparatus on the output from the system switching unit. A reception side clock output unit outputs a clock signal giving a processing timing of each process, and a clock frequency control unit adjusts a frequency of the clock signal giving the processing timing to the output processing unit. A frequency adjustment range calculation unit calculates an adjustment range of the frequency based on frequency deviation accuracy of the reception side clock output unit, frequency deviation accuracy of a transmission side clock output unit that outputs a clock signal giving a processing timing to a transmission process at a transmission apparatus on the transmission side, and a prescribed value of a frequency deviation.

Transmission apparatus and transmission system

A transmission apparatus includes redundant first communication devices configured to communicate with a communication apparatus provided in a first network, and redundant second communication devices configured to communicate with a communication apparatus provided in a second network. The second communication devices include respective first ends that are ends of redundant communication paths of the first communication devices, and the first communication devices include respective second ends that are ends of redundant communication paths of the second communication devices.

Transmission apparatus and transmission method

Communication system for performing an enhanced handover for a dual connection mobile device

In the optical transport system a transport frame generator divides a transport frame accommodating plural client signals into plural transmission signals. Subcarrier transmission units convert the signals into optical signals using different optical carriers and transmit the converted optical signals. Subcarrier reception units receive the transmitted optical signals and convert the optical signals into reception signals. A transport frame termination unit combines the reception signals to restore the transport frame. A time-demultiplexing processor time-demultiplexes the restored transport frame to be separated into the client signals. A time slot control unit determines a new time slot allocation when time-multiplexing the client signals in the transport frame and stops supply of electric power to a subcarrier transmission unit and a subcarrier reception unit that transmit and receive an optical signal to which the client signals are not allocated.

Optical transport system and resource optimization method

A framer in a transmission device allocates plural optical channel time slots to a plurality of logical prioritized paths. It allocates received client signals to the allocated time slots, and transmits the client signals by a plurality of optical subcarriers that use a plurality of optical wavelengths corresponding to the plurality of time slots. The framer includes: a time slot allocation unit that, in a case where an optical wavelength corresponding to a time slot allocated to a logical path having a high transmission priority is not used, allocates at least one of the plurality of time slots to the logical path having the high transmission priority while the time slot corresponding to the unused optical wavelength is avoided, to change the time slot allocated to the logical path having the high transmission priority.

Framer and framing method

Growing community of inventors

Yokosuka, Japan

Takuya Ohara