| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a road surface monitor of simple constitution and high accuracy using a microwave means. SOLUTION: This road surface monitor is provided with a transmitting means for transmitting a radio wave of specified wavelengthλamplitude-modulated in a fixed cycle, as a transmitted wave toward a monitored object road surface 1 from a transmitting antenna 4 fixed above by a fixed distance L from the monitored object road surface 1, a receiving means for receiving a reflected wave from the monitored object road surface 1 through a receiving antenna 5 installed side by side with the transmitting antenna 4; a mixer means for synthesizing the transmitted wave and received wave at the receiving means; an envelope detecting means for extracting a variable cycle component from the synthesized wave output of the mixer means; and a level detecting means for detecting the change of reflection quantity caused by moisture of the monitored object road surface 1, as the change of envelope output amplitude of the envelope detecting means.</p> |
