Hitachi-kokusai Electric Inc.

Kansei Corporation

Kabushiki Kaisha Koden Seisakusho

Hidefumi Ito

Masaki Suto

Naoki Hongo

Toshio Takada

Takashi Uchida

Takashi Yoshimura

Shuhei Miura

Jun Nishino

Junetsu Urata

Sigeru Ryugo

Hiroshi Takeda

Shoji Fujimoto

A distortion compensator compensates for distortion arising in an amplifier that amplifies a signal with improved efficiency. The distortion compensator includes a signal level detector which detects the level of a signal to be amplified by an amplifier, a distortion compensation execution unit which executes distortion compensation on the signal to be amplified according to a mode of distortion compensation corresponding to the signal level detected by the signal level and a correspondence between signal levels and distortion compensation control values as pairs, a distortion compensation control value correspondence updater which updates the correspondence between the signal levels and the distortion compensation control values used in the execution of distortion compensation, and a distortion compensation control value number controller which controls the values of stipulated parameters.

Distortion compensator

Disclosed is an amplifier apparatus that corrects mismatching of the filter transmission characteristic due to a change in the temperature of the amplifier apparatus itself and thereby stably amplifies the high-frequency signal. The amplifier apparatus converts a signal to be processed into one having an intermediate frequency band to thereby execute amplification processing. It comprises a local oscillator the oscillation frequency of that can be altered, a first frequency converter that converts the signal by the use of the oscillation frequency from the local oscillator into an intermediate frequency, a first band pass filter that band-limits the signal having the intermediate, an amplifier that amplifies the signal of the intermediate frequency that has passed therethrough, a second band pass filter that band-limits the signal of the intermediate frequency that has been output therefrom, a second frequency converter that converts the signal of the intermediate frequency that has passed therethrough into the original frequency by the use of the local-oscillation frequency, a temperature sensor that detects the temperature of each of the first and second filters , and a controller that alters the oscillation frequency of the local oscillator in correspondence with the detected temperature and thereby stabilizes the transmission characteristic of each of the first and second filters irrespective of the change in the temperature.

Amplifier apparatus and method for controlling a local oscillator frequency based on the detected temperature of if bandpass filters

An optical distance measuring equipment in which light from a light emission element is transmitted to an object through a light transmission lens, and light reflected on the object is received by a light reception element through a light reception lens so that a distance to the object is measured on the basis of light transmitting timing and light receiving timing. In the optical distance measuring equipment, a lens holding member for disposing the light transmission lens and the light reception lens substantially at the same distance relative to the light emission element and the light reception element respectively is provided in front of a light transmission/reception board on which the light emission element and the light reception element are installed.

Optical distance measuring equipment

Growing community of inventors

Tokyo, Japan

Hidefumi Ito