摘要：In low-frequency elastic wave through-the-earth communication system,because of multipath transmission caused by characteristics of the layered earth,the time domain equalizer is different from other wireless communication systems.A modified LMS algorithm of variable step size is proposed based on improvement of traditional *** the base of principle and simulation analysis,the improved Least Mean Square(LMS)algorithm is analyzed and the performances are compared between the improved LMS algorithm and traditional LMS *** the improved algorithm,the contradiction between convergence speed and the steady-state error is considered at the same ***,the improved algorithm has good convergence properties and channel-tracking performance.