Apparatus, methods and recording medium for imaging a subsurface using the waveform inversion in the laplace-fourier domain

PURPOSE: An apparatus, a method and a recording medium for imaging an underground structure using waveform inversion of a Laplace-Fourier domain are provided to stably obtain a speed model with long wavelength information and middle wavelength information. CONSTITUTION: An apparatus for imaging an underground structure using waveform inversion of a Laplace-Fourier domain includes a receiver and a signal processing unit. The signal processing unit comprises an input unit, a converting unit(202), a modeling data generating unit(203), and a parameter update unit(206). The converting unit converts measurement data in a time domain into measurement data in a Laplace-Fourier domain using an attenuation constant of a complex number. The modeling data generating unit sets an equation including a parameter by receiving a parameter showing a feature of a measurement target region. The modeling data generating unit calculates the equation in the Laplace-Fourier domain to calculate modeling data.