Mitsubishi Electric Corporation

Komatsu Corporation

Tokyo Yogyo Kabushiki Kaisha

Topcon Corporation

Sony Corporation

Mitsubishi Electric Research Laboratories, Inc.

Yoshino Gypsum Co., Ltd.

Kamatsu Ltd.

Tsuyoshi Yoshida

Keisuke Matsuda

Teiji Yamamoto

Takashi Sugihara

Shota Murakami

Kiyoshi Onohara

Masashi Binkai

Kenji Ishii

Yoshiaki Konishi

Hideo Yoshida

Noriko Saito

Keisuke Dohi

Tatsuya Kobayashi

Kieran Parsons

Hiroshi Miura

David Millar

Keisuke Kojima

Naoki Suzuki

Kazushi Nakata

Taira Ozaki

Hiroki Goto

Takanori Nagata

Akira Hashimoto

Daijirou Itou

Eiji Amada

Tsuyoshi Mizuno

Ryosuke Tomizawa

Keizo Aramaki

Daijiro Ito

Kenichi Higuchi

Tomohiro Yotabun

Kenji Kohriyama

Kazuyuki Onohara

Takuya Tsukada

Hiroshi Nishimoto

Nobuyuki Sato

Toshiaki Koike-Akino

Ken Nakajima

Takashi Mizuochi

Eiji Yagyu

Kazuo Kubo

Katsuhiro Shimizu

Masaaki Takahashi

Shinji Mitsuta

Shusaku Hayashi

Toshiyuki Tokura

Akira Himeno

Kazuyuki Ishida

Tatsuo Wada

Kentaro Enoki

Aritomo Uemura

Tatsuo Aira

Toshiaki Koike Akino

Takafumi Fujimori

Souichi Tsumura

Hisao Asada

Kenji Kooriyama

Katsumi Niimi

Sora Otaguro

Yasuhisa Shimakura

Hiroaki Shintaku

Tomohiro Noguchi

Hiroki Shima

Takanori Yamauchi

Takahiro Kodama

Seiki Nakamura

Tetsunori Yamashita

Shinya Nakamura

Shouta Murakami

Atsushi Ohyama

Mitsuko Mieno

Masaki Ushizawa

Daijiroh Tanaka

Toshiaki Akino

An optical distance measurer includes: a beam splitter splitting a laser beam and outputting as measurement light and reference light; a measurement light beam splitter splitting the measurement light and outputting as first measurement light and second measurement light; a reference light beam splitter splitting the reference light and outputting as first reference light and second reference light; a first optical system having a first Rayleigh length, the first optical system emitting the first measurement light to a target object; and a second optical system having a second Rayleigh length different from the first Rayleigh length, the second optical system emitting the second measurement light to the target object; a first receiver receiving the first reference light and first reflection light that is the first measurement light reflected by the target object and outputting a first receiving signal indicating the first reference light and the first reflection light; and a second receiver receiving the second reference light and second reflection light that is the second measurement light reflected by the target object and outputting a second receiving signal indicating the second reference light and the second reflection light.

Optical distance measurement device

An error correction coding apparatus that performs error correction coding using, as an error correction code sequence, a frame of m bits×n symbols input in m-bit parallel, where m and n are positive integers, includes: an error correction coding circuit that performs error correction coding using, as information bits, m bits×n symbols including known bits assigned to a bit sequence specified in the error correction code sequence and generate error correction coded parity bits; and a selector that replaces the known bits of the error correction code sequence with the parity bits.

Error correction coding apparatus and error correction decoding apparatus

An optical space communications transmission and reception terminal includes: an optical transceiver to convert transmission data into a transmission optical signal modulated at a symbol rate synchronized with a transmission clock signal and output it, and generate received data from a reception optical signal; an intensity modulation unit to generate an intensity-modulated transmission optical signal; a transmission clock source to supply a transmission clock signal; a fiber coupling unit) to output the intensity-modulated transmission optical signal as collimated light and couple the input optical signal to an optical fiber; an optical fiber amplifier to amplify the optical signal coupled to the optical fiber; a tracking mirror to output the optical signal to the fiber coupling unit and output the transmission optical signal to space; and an angle sensor to output a clock signal extracted from the optical signal divided by a beam splitter to the optical transceiver.

Optical space communications transmission and reception terminal and optical space communications system

A transmission code processing device includes: a signal point arrangement shaping encoding unit to perform conversion into a shaped bit of mi column; a systematic error correction encoding unit to generate a parity bit of mp column based on the shaped bit; a first symbol mapping unit to convert the shaped bit into a first modulation symbol; a second symbol mapping unit to convert the parity bit into a second modulation symbol; and a symbol multiplexing unit to multiplex the first and second modulation symbols, in which the first modulation symbol has one element in a first signal point set including ci signal point including an origin, the second modulation symbol has one element in cp signal point not including the origin, and the signal point arrangement shaping encoding unit performs signal point arrangement shaping in which the first modulation symbol has one element in the first signal point set.

Transmission code processing device, transmission code processing method, and optical transmitter

An optical transceiver includes processing circuitry to calculate, when test signals are sent to a transmission line from a transmitter and a receiver receives the test signals having passed through a wavelength filter, a bandwidth of the received test signals, the transmitter generating, as the test signals, a collection of narrowband signals, the narrowband signals having a narrower bandwidth than a bandwidth of the wavelength filter and having different frequencies, and the wavelength filter included in an optical splitter inserted in the transmission line, and the collection of narrowband signals including a narrowband signal having a higher frequency than a highest frequency in the bandwidth of the wavelength filter and a narrowband signal having a lower frequency than a lowest frequency in the bandwidth of the wavelength filter, and to determine a modulation rate and a modulation level of the transmission signal depending on the calculated bandwidth.

Optical transceiver, transmission signal determination method, and optical communication system

An error correction encoding device includes an encoding unit to generate soft decision error correction frame information including a bit array of m rows and N columns obtained by combining first bit string group information and second bit string group information, the first bit string group information including a bit array of m rows and N1 columns in which it is enabled to perform pulse amplitude modulation of a combination of bit values of each column of the first bit string group information into a modulation symbol by using a first symbol mapping rule, the second bit string group information including a bit array of m rows and N2 columns in which it is enabled to perform pulse amplitude modulation of a combination of bit values of each column of the second bit string group information into a modulation symbol by using a second symbol mapping rule.

Error correction encoding device and method for reducing the number of bits to be protected by soft decision error correction

A cutting apparatus is provided. The cutting apparatus includes a cutter disposed in a conveying path for conveying a plate-shaped object and configured to cut the object, a downstream conveyor disposed downstream of the cutter in the conveying path and configured to convey the object, and a foreign-matter adhesion preventer disposed between the cutter and the downstream conveyor and configured to prevent foreign matter scattered by the cutter from adhering to the downstream conveyor.

Cutting apparatus, apparatus for manufacturing sheet material, and apparatus for manufacturing gypsum building material

A subchannel encoding device is configured to include: a probability distribution shaping-encoding unit for dividing M&#xd7;N (M is an integer of two or more, and N is an integer of one or more) subchannels into N groups, shaping a probability distribution of transmission modulation symbols of each group on the basis of signal-to-noise ratios of the M&#xd7;N subchannels, and converting an information bit string into a shaped bit string corresponding to the probability distribution of the transmission modulation symbols of each group; a subchannel signal generating unit for generating each subchannel signal in the M&#xd7;N subchannels from the shaped bit string; and a signal multiplexing unit for multiplexing the M&#xd7;N subchannel signals generated by the subchannel signal generating unit to generate a subchannel multiplexed signal.

Subchannel encoding device, subchannel decoding device, subchannel encoding method, subchannel decoding method, and subchannel multiplexing optical communication system

Provided is an optical transmission device including: a symbol demapping unit; a likelihood generation circuit configured to generate likelihoods relating to the reception signal; and an error correction decoding unit configured to execute soft decision decoding. The likelihood generation circuit includes: a first one-dimensional-modulation lookup table configured to input the signal of the I-axis component as an argument to output a first likelihood; a second one-dimensional-modulation lookup table configured to input the signal of the Q-axis component as an argument to output a second likelihood; and a two-dimensional-modulation lookup table configured to input, as an argument, the signal being the concatenation of the signal of the I-axis component and the signal of the Q-axis component, to generate a third likelihood. The error correction decoding unit is configured to execute the soft decision decoding based on the first likelihood, the second likelihood, and the third likelihood.

Optical transmission device and likelihood generation circuit

In a distribution shaping method, information compression and distribution shaping are executed at the same time. A symbol sequence of a predetermined length is allocated to an input bit sequence of a predetermined length on a one-to-one basis. In the allocation, a bit sequence smaller in entropy is allocated a symbol sequence smaller in average power.

Distribution shaping method, distribution deshaping method, distribution shaping encoder, distribution shaping decoder, and transmission system

A transmission/reception device is configured to convert an optical signal based on a plurality of first optical signals having frequency bands different from each other into an electric signal and output the electric signal as a plurality of first electric signals; receive the plurality of first electric signals, change frequency bands of some or all of a plurality of second electric signals to narrow an interval between frequency bands of two second electric signals having frequency bands adjacent to each other, and output, as third electric signals, electric signals; to receive a plurality of the third electric signals, combine and output the plurality of third electric signals as a fourth electric signal; and receive the fourth electric signal, convert the fourth electric signal into an optical signal, and output the optical signal as a second optical signal.

Transmission/reception device and transmission/reception method

In a distribution matching circuit, output data of a plurality of LUTs forming a hierarchical tree structure sequentially designates a combination of signal point groups in a signal space managed by an LUT in an immediately lower level, and signal point information after distribution matching is output for each LUT in the lowermost level.

Distribution matching circuit, distribution dematching circuit, distribution matching method, distribution dematching method, and optical transmission system

A spatial optical transmitter modulates an optical signal of a single wavelength in accordance with a signal to be transmitted, divides the modulated optical signal into two, rotates polarizations of the two divided optical signals, and transmits the two optical signals as optical signals of two orthogonal polarizations to space.

Spatial optical transmitter and spatial optical communication system

A coherent receiver performing coherent detection on polarization multiplex light into which first polarization light and second polarization light are multiplexed, and splitting the polarization multiplex light into the first polarization light and the second polarization light, an adaptive equalizer compensating the waveform distortion of a signal superimposed onto the first polarization light by using a first FIR filter, compensating the waveform distortion of a signal superimposed onto the second polarization light by using a second FIR filter, and by decoding each of the signals whose waveform distortion has been compensated, generating their respective decoded data, an error ratio calculator calculating the bit error ratio of each decoded data generated by the adaptive equalizer, a margin calculator calculating a margin from the bit error ratio of an error correction limit in each bit error ratio calculated by the error ratio calculator, and a tap number controller setting up the numbers of taps of the first and second FIR filters by referring to the respective margins calculated by the margin calculator are included.

Optical receiver, light signal receiving method, and data reproduction device

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Tokyo, Japan

Tsuyoshi Yoshida