You’ve probably heard the term “RF,” or “radio frequency.” Radio frequency is all around us. It’s the energy that your phone, WIFI router, and countless other devices use to transfer data and communicate.
Cellular communication is based on RF, as is WIFI and a number of other technologies you’re probably hearing a lot about in home automation: Zigbee, Thread, Z wave, BLE, and BT (Bluetooth).
But there’s one more part of RF technology that deserves mention: Proprietary RF.
Proprietary RF refers to any radio frequency that is unique to a specific OEM, or original equipment manufacturer. These can vary in frequency range but are often under 928MHz. Proprietary RF is primarily used for simple communication between remote controls and more traditional home devices such as ceiling fans, garage doors, wireless doorbells, motorized shades, etc.
In relation to RF, “proprietary” means that every manufacturer of these devices has created their own communication protocol using these FCC predefined frequency bands. There isn’t a database that describes how these appliances/devices’ control schemes work.
What sets Proprietary RF apart is that while WIFI and BT are new and are still relatively expensive, low frequency RF remote controls and receivers tend to be much cheaper. In coming up their own protocol, the manufacturer almost always has an eye on cost – resulting in less expensive technology.
For about 25 years Proprietary RF has come almost standard with the purchase of home appliances. This will eventually change as the costs associated with WIFI and BT hardware drop. We’ll find that more and more appliances will come with standard WIFI or BT built in.
But don’t expect Proprietary RF to phase out completely. There’s still a future in the home for Proprietary RF and it all comes down to an inverse relationship between range and battery life.
Modern communications devices that operate on RF typically use 2.4 GHz and 5 GHz frequencies. These are able to provide higher data rates and send more information between devices. High GHz bands allow you to stream Netflix on your tablet, for example. However, even though higher GHz means better data, it also means shorter distances. This is where low frequency RF shines in comparison.
Think of a garage door opener. You can use it all the way down the street and still open your garage. For your laptop to work at the same range, you’d have to find a wireless router with incredible power. Because low frequency RF can transmit more efficiently, it can send very simple commands (very little data) over much longer distances (down your block) with relatively little power needed.
Your existing home appliances – the ceiling fans, motorized shades, and garage doors I mentioned – don’t need complex commands or payloads, but they often need to communicate over further distances or through walls. A 300MHz signal loses less energy than a 2.4 GHz signal does as it travels through space or through structures in your home. The lower loss and increased range of the sensor enables transmission at lower power, therefore using battery more efficiently with less-frequent timeouts.
So low frequency, proprietary RF will likely always have a place in the home market. As the IoT takes hold in more and more homes, solutions are needed that can connect our faster, data-heavy mobile devices with our slower but more efficient, low-frequency appliances. Solutions like these will enable us to keep the appliances we have while providing the connectivity we crave. It will truly be the best of both worlds.