Interesting Fact
When Wi-Fi signals propagate through space, they encounter the human body, resulting in reflection and attenuation. By analyzing these subtle signal changes, it is possible to detect whether there are people in a room, their locations, and even monitor vital signs such as breathing and heartbeat.
Application in Writing
Room Monitoring: The protagonist is illegally imprisoned, and their phone is confiscated. They utilize the Wi-Fi signals at the location of their captivity, using specific body movement patterns (such as Morse code) to interfere with the signals, ultimately being identified and located by accomplices outside. Medical Miracle: An elderly person living alone has a smart home system that analyzes daily patterns of Wi-Fi signal changes to determine that the elderly person has fallen unexpectedly and is exhibiting abnormal vital signs, thereby automatically alerting for help and saving their life.