The question comes up in every home networking forum: if 5 GHz WiFi is faster, why does it drop off when you move to the other side of the house? The answer is physics, not a bug in your router’s firmware. Frequency and Wavelength Are Inverse Radio waves are characterized by two linked properties: frequency and wavelength. The relationship between them is fixed by the speed of light — wavelength equals the speed of light divided by frequency.

Most devices show WiFi signal as a series of arcs — full bars, three bars, two bars, one bar, gone. The arc display is a hardware abstraction that tells you almost nothing useful for diagnosing problems or evaluating placement. Underneath it is a real number, expressed in dBm, that tells you exactly where on the performance curve your device is operating. Reading that number directly converts WiFi troubleshooting from guesswork into measurement.