Moreover, the transmission and reception of this kind of signal did not need satellite relay. The wristwatch could directly receive the signal.
Xia ruofei gave it a try. He could clearly locate the signal transmitter on his watch from tens of meters away. This meant that at least radio waves could be transmitted here, which made him feel more at ease.
The signal transmitter had a very low power consumption, and the battery it came with could last for about a month. It could also work continuously even in high temperatures, underwater, or other harsh environments.
Of course, the radio could be transmitted here, but the other members of the exploration team couldn't be called through the communication channel. This also meant that the other members were very far away from him, out of the effective range of the communication equipment. They might not even be in the same space as him.