We study the magnetosonic waves (MWs) propagating in magnetized plasmas comprising light warm ions, cold heavy ions and hot electrons at the Earth’s ionosphere. The dispersion relation is given and the effects of different physical parameters on the frequency of fast and slow MSWs are shown. We derive a KdV equation for the MSWs in multi-ion plasma and study the two-soliton and three-soliton overtaking collision of KdV MSWs by Hirota’s bilinear method. We show the trajectories and amplitude of solitons in this process, and the phase shift after collision. It is found that when solitons merge, it will form a new soliton whose amplitude first decreases then increases. The effects of physical parameters on the phase shift of multi-soliton collision are presented. It is worth noting that the solitons’ interaction can result in the redistribution of momentum and energy in the plasmas.

我们研究在地球电离层由轻热离子、冷重离子和热电子组成的磁化等离子体中传播的磁声波（MW）。给出了色散关系，并显示了不同物理参数对快、慢 MSW 频率的影响。推导了多离子等离子体中MSWs的KdV方程，并利用Hirota双线性方法研究了KdV MSWs的二孤子和三孤子超车碰撞。我们展示了这个过程中孤子的轨迹和振幅，以及碰撞后的相移。研究发现，当孤子合并时，会形成新的孤子，其振幅先减小后增大。给出了物理参数对多孤子碰撞相移的影响。值得注意的是，孤子的相互作用会导致等离子体中动量和能量的重新分布。