Abstract: In order to solve the re-entry blackout problem, based on the former research on magneto window antenna for improving propagation characteristic of electromagnetic wave in plasma sheath, the influence of external electromagnetic control is investigated, the magnet is NdFeB, and the applied voltage is 100 V. Numerical simulation of the flow fields without electromagnetic field, with magnetic field, with electromagnetic field are conducted by using flow field data of different flight altitude. Based on the simulation result, comparison of electronic density and attenuation constant nearby the antenna window with different parameters is shown, and the effects of aircraft flight altitude, the position of electromagnetic window antenna, electromagnetic frequency, the applied voltage electronic density and collision frequency on the electromagnetic window antenna are investigated. The results show that it is feasible to improve electromagnetic propagation in plasma sheath by electromagnetic window antenna, which has better results than magnetic window antenna. With proper working condition of electromagnetic window antenna and appropriate parameters setting, the propagation attenuation would be mitigated obviously by changing the dielectric parameters and the distribution of plasma, thus the phenomena of blackout would be mitigated or eliminated.