Study on Propagation Characteristics for Underground Communications Based on FEKO

In this paper, the propagation characteristics for underground communication are simulated and analyzed using the software of FEKO 7.0. Based on the proposed channel model, we compared and analyzed the distribution of E-field intensity at different positions in the manhole at two frequencies. The simulation results indicate that the underground antenna should not be placed in the center area of the manhole at the operating frequency of 915MHz. And the horizontally polarized underground antenna should be placed at least 0.5 meters away from the manhole cover to achieve better communication effect. Besides, for 2GHz operating frequency, vertical polarized underground antenna will be more suitable for underground communication requirements. The detailed analysis of the above results provides a theoretical foundation for the underground antenna to adapt to the radio environment to find the optimal receive characteristics.