A view of trees obstructing Wi-Fi signals.
This image shows how Wi-Fi waves decrease in amplitude as its further from the source (larger on the right where the source is and smaller on the left). According to Lamm and Vogel the picture “shows an idealized wifi data transmitted over a band that is divided into different sub-channels, which are shown in red, yellow, green and other colors.”
Routers and computers will send and receive data as waves that are 3 to 5 inches apart from each other. Lamm and Vogel say, “the wifi pulses are shown here as multicolored spheres radiating out from the source, near the right of the image.” A ‘normal’ field of Wi-Fi is typically spherical and can extend 65 to 100 feet.