磁感应成像(MIT)是对所测生物组织电导率进行图像重建的一种新型技术,生物组织所产生的涡流信号过于微弱制约着MIT检测装置的设计精度和重建图像的分辨率。该文基于涡流信号的特点,提出一种最大化减少主磁场信号的涡流检测方法,即对线圈传感器进行改进有效抵消主磁场信号从而增大涡流场。针对所提出的MIT测量模型,通过仿真实验,确定检测线圈最大化抵消主磁场的最优化参数,并在该最优模式下,对信号的线性和灵敏度进行测试,结果表明,该方法MIT信号的线性和灵敏度获得较满意效果。
Magnetic Induction Tomography(MIT) is a new technique for conductivity of biological tissue to reconstruct image.Weak eddy current signal within biological tissue restricts the precision of detection device and resolution of reconstruction image.A method of reducing the primary magnetic field as much as possible is presented based on the characteristics of eddy current signal.Sensor coils are improved to cancel the primary field signal,thus increasing the eddy current field.Simulation experiments are carried out for the MIT measurement model presented in the paper to determine the optimal parameters of detection coil to offset the primary field.Signal linearity and sensitivity is tested under this mode.The results prove that the method gets better effect in signal linearity and sensitivity of MIT.