The strengths of the ELF currents produced by heating the ionospheres over Beijing, Shanghai and Haikou by powerfully modulated HF wave are calculated under a typical transmitting condition, using the practical parameters of the ionospheres.

• 文中用实际的电离层参数,具体地估算了在典型发射条件下,极低频脉冲调制的高频电波加热北京、上海、海口上空电离层所能产生的极低频电流强度。