In this tutorial I’ll show you how to use an Arduino to decode signals from RF remotes, and re-send them to remotely control some mains switches and a garage door.Note: This guide was written for Australia, where it’s legal to operate low powered devices (25mW) in the 433MHz band without a licence. Check what’s legal in your own country. If you’re transmitting to (or on the same frequency as) a garage door opener / RC toy etc that you bought in your own country, it should be fine, provided you stick to the power limit.

Source: Decoding and sending 433MHz RF codes with Arduino and rc-switch