Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Japan Aerospace Exploration Agency

Mitsubishi Electric Cornoration

Mitsubushi Electric Corporation

Mitsubishi Electric Tokki Systems Corporation

Shumpei Kameyama

Masaharu Imaki

Nobuki Kotake

Yoshihito Hirano

Toshiyuki Ando

Takayuki Yanagisawa

Shusou Wadaka

Yusuke Ito

Tomonori Kimura

Hideaki Ochimizu

Hidenobu Tsuji

Kimio Asaka

Yuichi Nishino

Masahiro Kawai

Koichiro Misu

Tsutomu Nagatsuka

Eisuke Haraguchi

Mitsuhiro Koike

Fumio Shohda

Kenichi Hirosawa

Yutaka Kajiyama

Yuuichi Manome

Takashi Saito

Hiroshi Aruga

Atsushi Okamura

Hidetoshi Tanaka

Akihito Hirai

Toshio Wakayama

Kohei Sakai

Jiro Suzuki

Hiroshi Sakamaki

Yasuhisa Tamagawa

Tomoya Matsuda

Kei Suwa

Takeshi Sakimura

Yukari Takada

Junya Nishioka

Syuhei Yamamoto

Masahiro Hagio

Yosuke Tsuzaki

Yosuke Takagawa

Masashi Furuta

Yoshinori Okuno

Wakasa Kise

Mikio Takabayashi

Naoki Matayoshi

Hidetaka Kiyosue

Junia Nomura

Takayuki Kitamura

Wataru Yoshiki

A signal processing device calculates, as a moving speed of each of a plurality of observation targets, a relative speed of each of the targets with respect to a lidar device. A plurality of light pulses having different frequencies from each other are generated, each of the light pulses radiated and then scattered by each of the targets is received, and multiplexed light of each of the scattered light and the laser beam is detected. The signal processing device includes: a Doppler frequency calculating unit to calculate a Doppler frequency in a frequency of each of the scattered light and due to movement of each of the targets from the frequencies of the plurality of generated light pulses and a detection signal of each of the multiplexed light; and a speed calculating unit to calculate a relative speed of each of the targets from each of the Doppler frequency.

Signal processing device, signal processing method, and lidar device

A laser radar device includes: a light source for outputting laser light; a scanner for causing the laser light to scan; a first optical system for receiving the laser light caused to scan by the scanner and incident on the first optical system and emitting the incident laser light in such a manner that a horizontal component of the incident laser light is different from a horizontal component of the laser light to be emitted; and a second optical system for receiving the laser light caused to scan by the scanner and incident on the second optical system and emitting the incident laser light in such a manner that an incident area of the incident laser light in the horizontal direction is the same as an incident area of the first optical system in the horizontal direction, and an emission area of the incident laser light is different from an emission area of the first optical system.

Laser radar device

An optical transmission unit () transmits an optical signal having a light intensity set as a Low level component of a pulse. An optical partial reflector () is provided on a path through which transmission light is transmitted from a circulator () to the atmosphere, and reflects the optical signal. A detection unit () performs coherent detection on reception light using, as local light, a signal in a Low level section in the optical signal reflected by the optical partial reflector ().

A laser radar device calculates a wind speed for each of a plurality of divided sections obtained by dividing a trajectory drawn by a laser beam in front of a wind turbine.

Laser radar device, wind power generator, and wind measurement method

To provide a laser distance measuring apparatus which can increase the measurement frequency per unit time by suppressing the increase in the data amount expressing the measurement time, while ensuring the distance measurement precision and the measurable distance. A laser distance measuring apparatus measures, with a time resolution, a light receiving time which is a time from a time point when the laser beam generating unit emits the laser beam to a time point when the light receiving unit outputs the light receiving signal; calculates an object distance which is a distance to the object, based on the measurement result of the light receiving time by the time measuring device; and changes the time resolution of the time measuring device used for calculation of the object distance, based on detection information.

Laser distance measuring apparatus

A frequency shift correcting unit () which corrects a frequency shift of a plurality of first signal spectra within the same time range with respect to a frequency of first laser light beam and corrects a frequency shift of a plurality of second signal spectra within the same time range with respect to a frequency of second laser light beam, and a spectrum integrating unit () which integrates a plurality of first signal spectra corrected by the frequency shift correcting unit () and integrates a plurality of second signal spectra corrected by the frequency shift correcting unit () are provided, and a molecular concentration calculating unit () calculates a concentration of molecules in the atmosphere from the first and second signal spectra integrated by the spectrum calculating unit ().

A data processing device of the present invention includes: a data communication device configured to communicate with a laser radar device to acquire a value of line-of-sight wind-speed, a laser emission angle, attitude information, position information, and a time; a storage device configured to store the value of line-of-sight wind-speed and the time; a central processing unit configured to run a data selector to select a value of line-of-sight wind-speed stored in the storage device and being present within a set time period from a time about the value of line-of-sight wind-speed which is newly acquired by the data communication device, and configured to run a wind vector calculator to calculate a wind vector using the newly acquired value of line-of-sight wind-speed and using the selected value of line-of-sight wind-speed; and a memory configured to preserve the data selector and the wind vector calculator.

Data processing device, laser radar device, and wind measurement system

Included are: a first dielectric multilayer film () for transmitting a wavelength band including a wavelength of signal light () and reflecting first excitation light (), the first dielectric multilayer film () being disposed on one of two end surfaces of a core (), a first inner cladding (), a first outer cladding (), and a second outer cladding (); and a second dielectric multilayer film () for transmitting a wavelength band including the wavelength of the signal light () and reflecting the first excitation light (), the second dielectric multilayer film () being disposed on the other one of the two end surfaces.

Planar waveguide and laser amplifier

The laser radar device includes: a modulated light generator configured to generate modulated laser light using frequency modulation based on a control parameter; an optical combiner configured to combine the received light and the local light to generate interference light; a photodetector configured to detect the interference light and output an electrical signal; a frequency-to-voltage converter configured to convert the electrical signal into a voltage signal; a characteristic calculator configured to measure a characteristic value of the voltage signal; an evaluator configured to evaluate, on a basis of the characteristic value, whether a center frequency of a spectrum of a return signal component is within a range of a demodulation band of a demodulation circuit; and a parameter setting unit configured to change the control parameter when it is evaluated that the center frequency is not within the range of the demodulation band.

Laser radar device and method for controlling frequency modulation

In a plane perpendicular to the optical axis () of a lens (), the direction in which the cylindrical surface has zero curvature is the direction of generatrix of the lens (), and the direction in which the cylindrical surface has non-zero curvature and that is orthogonal to the direction of generatrix is the direction of curvature of the lens (). A light source () is disposed at the focal position () in the direction of generatrix on the side of the incident surface () of the lens (), and emits light toward the incident surface () of the lens (), the light having a difference between the divergence angle in the direction of generatrix of the lens () and the divergence angle in the direction of curvature of the lens ().

Parallel light generation device

In conventional laser radar systems, the wind velocity measurement accuracy cannot be improved without changing their time gate widths, which is a problem. A laser radar system according to the present invention includes: an optical oscillator to perform laser light oscillation; an optical modulator to modulate the laser light by oscillation of the optical oscillator; an optical antenna to emit the laser light modulated by the optical modulator into the atmosphere and to receive scattered light from an irradiated target as reception light; an optical receiver to perform heterodyne detection on the reception light received by the optical antenna; and a signal processor to calculate a spectrum of a reception signal obtained by the optical receiver's performing heterodyne detection, to decompose the spectrum using signal-to-noise ratios, and to calculate a velocity of an irradiated target from a decomposed spectrum.

Laser radar system

To provide a laser distance measuring apparatus that can set the irradiation range of the laser beam to the front ground surface appropriately regardless of the inclination of the front ground surface. A laser distance measuring apparatus controls the scanning mechanism to performs two-dimensional scan which scan laser beam in an irradiation angle range of the right and left direction to the traveling direction of own vehicle and scans laser beam in an irradiation angle range of the up and down direction with respect to the traveling direction of own vehicle; detects a relative inclination information of the up and down direction of a ground surface in front of own vehicle with respect to a ground surface where own vehicle is located; and moves the irradiation angle range of the up and down direction to up side or down side according to the relative inclination information.

A laser radar apparatus includes: a scanner capable of beam scanning at a first angular speed; a measurable wind distance calculator monitor to calculate and to monitor a measurable wind distance based on wind measurement data obtained through beam scanning by the scanner; an optical axis angular correction amount deriver to derive an optical axis angular correction amount being able to obtain the largest distance of the measurable wind distance, based on a first angular speed and the wind measurement data obtained through beam scanning at a second angular speed lower than the first angular speed, when decrease of the measurable wind distance is detected by the measurable wind distance calculator monitor; and an optical axis corrector to correct an optical axis angular deviation between transmitted light and reception light, based on the optical axis angular correction amount.

Laser radar apparatus

A device includes a light source () for generating light with a single wavelength; a modulator () for modulating the light generated into transmission light; a beam scanner () for carrying out beam scanning by which the transmission light modulated is radiated, and the light reflected is received; a beam scanning controller () for controlling the radiation direction; a signal processing unit () for performing wind measurement through heterodyne detection using the light generated and the corresponding received light; and an optical axis corrector () for correcting the optical axis angular shift between the transmission light and the received light, which accompanies the beam scanning, with respect to the received light used by the signal processing unit () or the transmission light used by the beam scanner (), on the basis of the radiation direction of the beam scanner (), the angular speed of the beam scanning and the wind measurement distance.

The problem with a conventional laser radar device is that the SNR of a value of a wind speed degrades due to motion. A laser radar device according to the present disclosure includes: an optical oscillator to emit laser light; an optical modulator to modulate the laser light generated by the optical oscillator; an optical antenna to emit the laser light modulated by the optical modulator into the air, and to receive, as received light, scattered light scattered by an irradiation target; an optical receiver to perform heterodyne detection on the received light received by the optical antenna; a sensor to detect one or more motion amounts of the optical antenna; and a signal processor to calculate spectra of respective received signals obtained by the heterodyne detection performed by the optical receiver, to correct the spectra by using the one or more motion amounts detected by the sensor, to perform an integration of the corrected spectra, and to calculate a speed of the irradiation target from a spectrum resulting from the integration.

Growing community of inventors

Tokyo, Japan

Shumpei Kameyama