Invention Application
- Patent Title: Paving material for absorbing electromagnetic wave and pavement structure using it
- Patent Title (中): 用于吸收电磁波和路面结构的铺路材料
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Application No.: US10491319Application Date: 2001-09-28
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Publication No.: US20050013661A1Publication Date: 2005-01-20
- Inventor: Toshio Saito , Kenichi Harakawa , Yoshitaka Wakinaka , Takeshi Kunishima , Kenichi Yoshimura , Yoshifumi Fujii , Shin-ichiro Andoh , Takeo Iwata , Masakazu Sato
- Applicant: Toshio Saito , Kenichi Harakawa , Yoshitaka Wakinaka , Takeshi Kunishima , Kenichi Yoshimura , Yoshifumi Fujii , Shin-ichiro Andoh , Takeo Iwata , Masakazu Sato
- International Application: PCT/JP01/08532 WO 20010928
- Main IPC: E01C7/00
- IPC: E01C7/00 ; E01C9/00 ; E01C11/16 ; H01Q17/00

Abstract:
An electromagnetic absorber formed of conductive fiber or the like, such as carbon fiber having an overall length corresponding to the wavelength of electromagnetic waves to be absorbed, is mixed into a base material to form an electromagnetic wave-absorbing pavement material. The electromagnetic wave-absorbing pavement material is used to form a pavement having an electromagnetic wave absorbing course. Further, an electromagnetic wave reflecting course is disposed under the electromagnetic wave absorbing course, and the electric length of the electromagnetic wave reflecting course is set to a predetermined value in relation to the dielectric constant so that electromagnetic waves reflecting off the surface of the electromagnetic wave absorbing course and electromagnetic waves reflecting off the electromagnetic wave reflecting course have opposite phases and thereby cancel each other out, whereby the electromagnetic waves are absorbed well. Moreover, the pavement having the electromagnetic wave absorbing course is formed such that the average dielectric constant along a plane orthogonal to a direction of thickness of the electromagnetic wave absorbing course increases from the top surface to the bottom surface thereof. With this structure, the electromagnetic waves easily enter the top surface of a surface course formed of the electromagnetic wave-absorbing pavement material. Thus, the electromagnetic waves directly reflecting off the top surface of the surface course formed of the electromagnetic wave-absorbing pavement material (i.e., directly reflected waves) are reduced, such that the proportion of the electromagnetic waves entering the surface course formed of the electromagnetic wave-absorbing pavement material is increased. As a result, the electromagnetic waves are efficiently absorbed by the electromagnetic wave absorbing course.
Public/Granted literature
- US07160049B2 Paving material for absorbing electromagnetic wave and pavement structure using it Public/Granted day:2007-01-09
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