A WiFi extender needs to be placed between the location where you desire better wireless coverage and your wireless router. Further, WiFi extenders don't rebroadcast from the wireless channel used by your wireless router. They rebroadcast from a different wireless channel. On the other hand, a WiFi booster performs the task of rebroadcasting the existing WiFi signals. Additionally, it communicates directly with your gateway or WiFi router by using a wire. The WiFi booster makes use of a wire or cable, just the way a cellular tower does. These wires and cables are a medium of communication to the router or source.