Title:
UNDERGROUND TRANSMISSION SYSTEM
Document Type and Number:
Japanese Patent JP3810990
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide an underground transmission system adopting a non-cut and cover method or the like, that can easily and quickly realize joining of rods and a low-cost drilling unit.
SOLUTION: The underground transmission system is provided with a transmitter (10), that transmits a frequency-modulation signal to underground, a receiver (20) that receives the frequency modulated signal sent from the transmitter (10) and propagated underground and demodulates the signal, and also with a waveform correction section (40) that corrects the amplitude of the signal demodulated by the receiver (20), depending on its frequency components.
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Inventors:
Yoshimasa Ito
Toshimitsu Nozu
Suzuki Morio
Makoto Ishii
Kenji Hisashima
Toshimitsu Nozu
Suzuki Morio
Makoto Ishii
Kenji Hisashima
Application Number:
JP2000200056A
Publication Date:
August 16, 2006
Filing Date:
June 28, 2000
Export Citation:
Assignee:
Photoelectric Manufacturing Co., Ltd.
International Classes:
G01V3/12; H04B13/02; G01S13/88; H04B7/005; H04L27/10; (IPC1-7): H04B13/02; G01S13/88; G01V3/12; H04B7/005; H04L27/10
Domestic Patent References:
| JP11083995A | ||||
| JP2000050104A | ||||
| JP8313647A | ||||
| JP7303123A | ||||
| JP9089807A |
Attorney, Agent or Firm:
Toshihiko Sakurai
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