Comparison of Measurement Method for Eddy Current Signal of Biological Tissue in Magnetic Induction Tomography

Magnetic induction tomography (MIT) is a new technique for conductivity of biological tissue to reconstruct image. Weak eddy current signal in-vivo constraints the precision of detection device and resolution of reconstruction image. Coil sensor is improved at source in order to cancel the primary magnetic field and increase eddy current field. The paper describes several eddy current detection methods including axial gradiometer, planar gradiometer, maximum compensation coil for simulating, and the induced signals in the detection coils are made to be compared. Results prove that SCR (signal carrier ratio) with canceling method is 10² ~ 10⁵ order than that of without any canceling method. The induced signal is linear with the operation frequency and the frequency of compensation methods are lower than that of normal coils.