Chapter 14. Cutting the Cord: Radio Signals
While infrared is nice and simple, there are some real drawbacks. For instance, the low data rate and the need to have line of sight to the receiver.
The next step is to use proper radio transmission. There are plenty of different types of radio transmission for data: there’s Bluetooth, Bluetooth Low Energy (sometimes known as Bluetooth Smart or BLE), Zigbee, WiFi, LoRa, and many others.
While very powerful, most of these systems use complicated radio transceiver chips. However, there are still some radios that are extremely simple—for example, the kind often used by cheap wireless sensors or wireless doorbells.
These use simple AM transmitters and receivers (see Figure 14-1) that transmit in the free ...