| 摘要 |
<P>PROBLEM TO BE SOLVED: To measure a gas flow velocity at a predetermined remote position with high precision through a relatively simple equipment configuration while hardly influenced by attenuation of wave motion due to dust even in a bad environment of much dust. <P>SOLUTION: Since an electromagnetic wave called a microwave or millimeter wave is used as wave motion and has a wavelength of mm to cm order, transmissivity to those electromagnetic waves is secured in an atmosphere in which there are many ordinary dust particles of approximately 0.1-1 mm in diameter while a slight scattered wave is generated, so a gas flow velocity can be measured even at a remote place relatively distant from a transmission antenna 23 and a reception antenna 24. Further, since an electromagnetic wave generated by modulating an electromagnetic wave with pseudo noise is transmitted and a received scattered wave is detected through correlation processing using the pseudo noise, a fine scattered wave can be detected with high sensitivity or high noise suppression performance, so the fine scattered light at the place remote from the transmission antenna 23 and reception antenna 24 is detected to measure the gas flow velocity. <P>COPYRIGHT: (C)2013,JPO&INPIT |
