| 摘要 |
<p>PURPOSE:To eliminate a horizontal fringe image and an oblique fringe image included in an original image and obtain clear images such as of an underground buried pipe by creating the original image of the section at a hidden location based on the time difference between emitted electromagnetic waves and reflection waves and then performing a two-dimensional Fourier transform processing vertically and horizontally to the original image. CONSTITUTION:Electromagnetic waves emitted from an antenna 3 are reflected by an underground buried pipe 2 and reflection waves are received by an antenna 7 and are given to a reception circuit 8. Electromagnetic waves are emitted from the antenna 3 and the time difference until a signal is received by the antenna 7 corresponds to the distance between the surface of the ground 1 and the pipe 2. When the antennas 3 and 7 are so moved that they cross the pipe 2, the original image of the section within the vertical surface of the ground 1 including the pipe 2 is obtained. A processing circuit 9 constituted by a microcomputer etc. performs two-dimensional Fourier transform processing of the original image vertically and horizontally, eliminates the frequency components of the horizontal fringe image and oblique fringe image of the original image from a two-dimensional Fourier transform image, and further performs two-dimensional inverse Fourier transform processing, thus restoring the image.</p> |
