
The second reason is the use of foil as a screen to amplify and direct the Wi-Fi signal.
Some people use foil or aluminum cans as reflectors behind the router to improve signal propagation throughout the home. In theory, this can work if the reflector is correctly bent and positioned, and if the distance to it is adjusted to the length of the router’s antenna or the wavelength of the signal. However, improper use of such a screen may damage the Wi-Fi transmitter.
