Fujitsu Corporation

Nippon Telegraph and Telephone Corporation

Mitutoyo Corporation

Toshio Kawasaki

Hiroyoshi Ishikawa

Kazuo Nagatani

Yuichi Utsunomiya

Tomonori Sato

Tomoya Ota

Alexander Nikolaevich Lozhkin

Chiyoshi Akiyama

Mitsuhiro Ono

Takanori Iwamatsu

Nobukazu Fudaba

Yoji Ohashi

Tokihiro Miyo

Shigemi Aizawa

Toru Maniwa

Hajime Hamada

Kenzo Kobayashi

Shigekazu Kimura

Hiroyuki Kiyanagi

Atsushi Honda

Takenori Ohshima

Yoshihito Aono

Hikaru Ishikawa

Toshio Tamura

A slot antenna apparatus that includes a waveguide including a sidewall and having an extending direction, a slot provided on the sidewall, and a dielectric member that is attached to the waveguide and is slidable in the extending direction with respect to the slot, the dielectric member including a first section and a second section, the first section covering the slot at a first slide position, the second section covering the slot at a second slide position next to the first slide position, and the first section and the second section having different relative permittivities or different thicknesses with each other.

Slot antenna apparatus, communication system, and method for adjusting angle of radio waves emitted from slot antenna apparatus

A distortion compensation device includes a generating unit, a calculation unit, a conversion unit, and a distortion compensation unit. The generating unit generates, from an output signal of a power amplifying unit that amplifies transmission signals having a plurality of different bands, a superimposed signal in which the transmission signals having the different bands have been superimposed. The calculation unit calculates, based on the superimposed signal, a coefficient indicating a forward characteristic of nonlinear distortion of the power amplifying unit associated with each of the transmission signals having the different bands. The conversion unit converts the coefficient calculated by the first calculation unit to a coefficient indicating an inverse characteristic of the nonlinear distortion of the power amplifying unit. The distortion compensation unit performs, by using the coefficients converted by the first conversion unit, a predistortion process on each of the transmission signals having different bands.

Distortion compensation device and distortion compensation method

A multiantenna communication device forms a directional beam by adding an antenna weight to respective signals of a plurality of antenna elements. The multiantenna communication device includes: a processor that executes performing distortion compensation on a transmission signal by using a distortion compensation coefficient; a plurality of power amplifiers that are provided corresponding to the antenna elements, and that amplify the transmission signal subjected to the distortion compensation by the processor; a multiplexer that multiplexes signals output from the power amplifiers to feed back; and an analog/digital (A/D) converter that A/D converts a multiplex feedback signal that is obtained by the multiplexer, wherein the processor executes updating the distortion compensation coefficient by using the multiplex feedback signal A/D converted by the A/D converter and the transmission signal.

Multiantenna communication device and coefficient update method

A distortion compensation device includes an electric power amplifier that amplifies a transmission signal, and a processor that executes a process including: first identifying, by using a series that includes a plurality of coefficients or by using a look-up table that stores therein distortion compensation coefficients, an inverse characteristic of nonlinear distortion generated in the transmission signal in the electric power amplifier; second identifying, by using a plurality of coefficients, an inverse characteristic of linear distortion generated in the transmission signal in the electric power amplifier; and setting the coefficients for the first identifying and the second identifying such that a coefficient of a term with a degree of 1 in the series used in the first identifying or a sum of the plurality of coefficients used in the second identifying is a constant.

A distortion compensation apparatus includes: a generation unit that generates a first signal to be used on a transmission side and a feedback side in common; a conversion unit that converts a frequency of a third signal that is to be an even-order distortion compensation signal by using a second signal that is based on the first signal; and a compensation unit that compensates an even-order distortion in a transmission signal caused by amplification by using a signal obtained by frequency conversion for the third signal by the conversion unit.

Distortion compensation apparatus and distortion compensation method

A distortion compensation apparatus include: a feedback unit that generates a feedback signal containing a first frequency component in which a plurality of odd-order distortions are superimposed and a second frequency component in which a plurality of even-order distortions are superimposed according to output of a power amplifier which amplifies a transmission signal; and a signal processor that separates the first frequency component and the second frequency component from the generated feedback signal and performs signal processing.

A peak suppression device includes an acquiring unit that acquires multiple envelopes of carrier signals that are included in a multicarrier signal, an adding unit that adds the envelopes to generate a combined envelope, a detecting unit that detects a peak value and a peak timing of the multicarrier signal by using the combined envelope, and a suppressing unit that suppresses a peak of the multicarrier signal in accordance with the peak value and the peak timing.

Peak suppression device

A distortion compensation device for correcting balance between a first branch and a second branch, includes: an adjustment unit that is arranged in an input stage of a first nonlinear amplifier on the first branch and outputs a signal obtained by adjusting a phase and an amplitude of a first branch signal by using a balance correction amount to the first nonlinear amplifier; a first calculation unit that calculates a first inverse distortion characteristic of an entire outphasing amplifier based on an input signal and a combined signal; a second calculation unit that calculates a replica signal of the first branch signal based on the calculated first inverse distortion characteristic, a second branch signal, and the combined signal; and a third calculation unit that calculates the balance correction amount based on the calculated replica signal of the first branch signal and the signal output from the adjustment unit.

An amplification device includes a first filter configured to pass a predetermined frequency component of a first digital signal phase-modulated with a constant amplitude; a first distortion compensator configured to compensate the signal output from the first filter in advance for distortion occurring in an amplified signal, based on a first distortion compensation coefficient dependent on an amplitude of the signal output from the first filter; a first converter configured to convert the signal compensated by the first distortion compensator into a first analog signal; and a first amplifier configured to amplify the first analog signal.

Amplification device and amplification method

A power amplifier apparatus includes an amplifier configured to amplify an input signal converted into an analog signal, a distortion compensator circuitry configured to perform a pre-distortion process to an input signal at a second sampling rate higher than a first sampling rate at which the input signal is converted into an analog signal, a remover configured to remove a frequency component exceeding a frequency band corresponding to the first sampling rate from the input signal subjected to the pre-distortion process, a first rate converter configured to convert a sampling rate of the input signal from which the frequency component is removed from the second sampling rate to the first sampling rate, and a first signal converter configured to convert the input signal the sampling rate of which is converted into an analog signal at the first sampling rate to supply the input signal converted into the analog signal to the amplifier.

Power amplifier apparatus, transmitter apparatus, and method of controlling the power amplifier apparatus

An amplifying device including: a first amplifier configured to generate a first output signal by amplifying an input signal, a second amplifier configured to generate a second output signal by amplifying the first output signal, and a processor configured to perform a first compensation by compensating a distortion for the second amplifier in accordance with the first output signal and the second output signal.

Amplifying device, distortion compensating device, and amplifying method

A distortion compensation device includes: a memory configured to store a first and second table, different addresses being assigned to the first and second table respectively, each of the addresses being related to a distortion compensation coefficient to compensate for a non-linear distortion, a first address in the first table and a second address in the second table corresponding to respective first and second ranges of power or amplitude of a transmission signal, and parts of the first and second ranges overlapping each other; and a processor coupled to the memory and configured to: update the respective distortion compensation coefficients related to the first address and the second address simultaneously, in accordance with a single value of the power or the amplitude, and compensate for the non-linear distortion generated by an amplifier amplifying the power of the transmission signal, by using at least one of the first and second table.

Distortion compensation device and distortion compensation device method

A modulating device including: a first convertor configured to generate a converted analog signal by analog conversion on a input digital signal, a modulator configured to generate a modulated signal by quadrature modulation, a phase shifter configured to generate a phase shift signal by phase rotation, a demodulator configured to generate a demodulated signal by quadrature demodulation, a second convertor to generate a converted digital signal by digital conversion, a calculating circuit configured to estimate a the first direct current offset based on the input digital signal and the converted digital signal, the first direct current offset being a noise of digital current component generated between the input digital signal inputted to the first convertor and the output signal inputted to the demodulator, and a correcting circuit configured to correct at least one among from the input digital signal to the output signal based on the first direct current offset.

Modulating device and modulation method

A distortion compensation device includes: a distortion compensator configured to output, to a power amplifier, a predistortion signal obtained by performing distortion compensation processing on a transmission signal by using a distortion compensation coefficient, wherein the distortion compensator limits bands of a reference signal and a feedback signal so that the bands fall in a pass band and updates the distortion compensation coefficient based on an error between the reference signal and the feedback signal, the reference signal corresponding to the predistortion signal, the feedback signal corresponding to an output feedback of the power amplifier.

In an image measuring device that performs, on a work piece to be measured, low brightness continuous illumination and one of stroboscopic illumination and continuous illumination with high brightness, a common high-brightness LED is used, and driving circuits are switched between pseudo-continuous illumination and one of stroboscopic illumination and continuous illumination. In the pseudo-continuous illumination, an average brightness is reduced by pulse lighting. In the stroboscopic illumination, high brightness light is emitted instantaneously. The switching between the pseudo-continuous illumination and one of the stroboscopic illumination and continuous illumination may be performed by changing a lighting cycle of the high-brightness LED.

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Kawasaki, Japan

Toshio Kawasaki