| 摘要 |
A method of imaging an object, such as a diseased human heart or bone, in a nontransparent medium, such as the human body, involves placing an array of transmitters (12, 13) and receivers (14, 15) in operational association with the medium (16). The transmitters (12, 13) generate a harmonic (frequency domain) or pulse (time domain) primary EM field which propagates through the medium (16). The primary field interacts with the object to produce a scattered field, which is recorded by the receivers (14, 15). The scattered EM field components measured by the receivers (14, 15) are applied as an artificial EM field to generate a backscattering EM field. Cross power spectra of the primary and backscattering fields (in frequency domain) or cross correlation between these fields (in time domain) produce a numerical reconstruction of an EM hologram. The desired properties of the medium (16), such as conductivity or dielectric permittivity, are then derived from this hologram.
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