It’s odd how even in your own living room the Wi-Fi signal seems to have varying levels of strength. Wouldn’t it be useful to see in 3D what the signal looks like? This guy creates a brilliant way to map invisible Wi-Fi signals. The resulting image is quite surprising.
Using a single ESP8266 hooked up to a WS281 LED light, the video maker connects this device to his computer and moves it around, noticing a dramatic change in the color of the LED light. Colors go from blue to green to yellow or orange. This is a signal for the RX power at every point the device is moved to. The video maker first played around with this by using the long exposure on his camera set to the lowest possible ISO, and dimming the focus so that only the light remained. This resulted in an interesting pattern of colors, with blue being the best and red and orange being the worst. He then took this to the next step by recreating this with a large mechanical device, which can move around much larger spaces and zigzag with more consistency and precision. When placed in 3D imaging, the space showed a surprisingly wide variety of signal strength, with cloudy, thicker areas indicating a stronger Wi-Fi signal, and empty areas indicating a weaker signal.