摘要
In this paper, development of through-the-earth communication technologies is summarized, as well as the operating principles and performances. The propagation loss, frequency band and power efficiency are also analyzed. We can know that among these technologies, the antenna induction method is more popular, but the communication system with ground electrodes is more promising due to its high energy efficiency. The communication with elastic wave （seismic） is not suitable for emergency communication when the accidents of rock burst or land slide occur.
基金
Foundation item： National Nature Science Foundation of China （No. 61272432）
