| 摘要 |
<p>The underwater electrical signal transmission system, for transmitting electrical signals into the depths of the sea and horizontally through it using the sea itself as transmission medium in place of air, has its transmitters each connected via isolating transformers to feed lines leading to electrodes placed beneath the surface of the sea or on the surface. Electrical signals are propagated through the sea water between electrodes and their information retrieved from variations in their electric and/or magnetic fields. The system uses extremely low frequencies, e.g. 200 Hz., for transmission over the large stretches of water.</p> |
