What is Sub 1Ghz RF , its range & the importance of Sub 1Ghz for wireless IOT applications

A what-is & how-to guide to use Sub 1Ghz for IOT wireless applications involving the internet of things.


1What is Sub 1Ghz RF?

Sub 1Ghz RF operates in the ISM spectrum bands below Sub 1Ghz – typically in the 769 – 935 MHz , 315 Mhz and the 468 Mhz frequency range. This spectrum band below 1Ghz is particularly useful for RF IOT applications

2Why is the Sub 1Ghz RF preferred to the 2.4Ghz RF for IOT applications?

Applications for IOT or the internet of things, are typically low power. The Sub 1Ghz offers several advantages over the 2.4Ghz spectrum for such IOT applications.

  • Range of Sub 1Ghz wireless: Sub 1Ghz offers more range than the 2.4Ghz. If range is an important criteria for your IOT product, then the Sub 1Ghz is a better choice. Sub 1Ghz wireless transmission offers 1.5-2 times more distance coverage than the 2.4Ghz spectrum. Also, the Sub 1Ghz wireless spectrum has a long range mode that can have more than 100 km coverage for your IOT application
  • Lower Power Consumption: Wireless Sub 1 Ghz RF needs a lower power signal from the transceiver compared to the 2.4Ghz spectrum to get the same output power signal at the receiver. This makes the sub 1Ghz RF a great choice for battery operated IOT sensor devices.
  • Interference: IOT Sensor products using the wireless Sub 1Ghz spectrum can handle interference better. This is because they operate on a lower frequency with fewer existing applications using that spectrum. Also, the lower frequency ISM bands enable the Sub 1Ghz transmissions to weave between buildings in an urban environment better.

Sub 1Ghz Range : The over-reaching feature of the Sub 1Ghz spectrum band

The superior range of Sub 1Ghz is probably the best feature of this spectrum band. Typically, many wireless applications
fail only because all the nodes cannot be reached by the existing protocol. By spanning a larger range, especially at lower baud rates, Sub 1Ghz is becoming a preferred alternative vs 2.4Ghz

Wireless RF IOT applications for Sub 1Ghz


Ideal RF IOT wireless applications for Sub 1Ghz include smart metering and industrial lighting. These IOT applications typically cover harsh environments. The long range and the lower interference features of the Sub 1Ghz spectrum band make it a perfect fit for these IOT applications.

3Sub 1Ghz Wi-Fi

Often, Wi-Fi over Sub 1Ghz is becoming a popular option for several wireless applications. Industrial lighting is of course a popular application for Sub 1Ghz Wi-Fi, but recently, a lot of hardware RF designers are also using Sub 1Ghz Wi-Fi for home automation. One reason for using WiFi over Sub 1Ghz is the effective handling of interference by Sub 1Ghz.

4Wireless Standards & protocols that fit into Sub 1Ghz RF- LoraWan & Sigfox

sigfox using sub1ghz

  • Sigfox is a technology that has a higher range than Wi-Fi Networks and a lower range than cellular networks. It typically uses the 900 Mhz (sub 1Ghz) spectrum band to provide a range upto a few miles in the urban environment.
  • LoraWan is a technology that provides Wide Area Networks (WAN) at a lower cost. Lorawan works in various Sub 1Ghz frequency bands. These include the 902-928 Mhz band in the US and the 779-787 MHz & 470-510 MHz bands in China.

5Wireless Sub 1Ghz Modules to prototype your IOT application

atmel_and_microchip wireless sub 1Ghztexas-instruments modules

The Sub 1Ghz ISM frequency band is becoming very popular for IOT applications needing long range and low power. As a result, companies like Texas Instruments, Atmel,Semtech and Silicon Labs have developed interesting modules to kick-start your RF Sub 1Ghz IOT application.These sub 1Ghz modules typically have low power transceivers and receivers.

The makers of the CC1310 Launchpad Evaluation Module have a special claim to fame. CC1310 has been proved to support a range of over 100 km using Sub 1Ghz RF and LoraWan technology. Read the reviews of Sub1Ghz modules for IOT prototypes

In summary,Sub 1Ghz RF is getting very popular for interesting low power IOT applications and could make smart cities possible.