The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 07, 2013
Filed:
Jan. 31, 2011
Takashi Asahara, Tokyo, JP;
Hamaki Inokuchi, Tokyo, JP;
Takashi Asahara, Tokyo, JP;
Hamaki Inokuchi, Tokyo, JP;
Japan Aerospace Exploration Agency, Tokyo, JP;
Abstract
The object of the present invention is to provide an air data sensor that does not require an external input of a reference velocity as a Doppler LIDAR, has a function of autonomously determining the absolute airspeed, and has no position error. The optical air data sensor in accordance with the present invention is an optical air data sensor, mounted on an aircraft, for emitting a laser light as a transmission light into atmosphere, and then receiving a laser scattered light produced by scattering of the laser light by aerosol present in the atmosphere as a reception light, thereby to measure an airspeed and a wind velocity of airflow in a distant region on the basis of a Doppler shift amount between the transmission light and the reception light, wherein a true airspeed is autonomously measured, without setting a reference velocity, by successively sweeping a frequency offset corresponding to a reference velocity for providing an offset to a measurement frequency, and performing this sweeping within a frequency range in which the Doppler shift amount is measured.