In the ever-evolving field of wireless communication, Sub-1GHz technology has emerged as a significant player, offering a unique set of characteristics that make it suitable for a variety of IoT applications.

This article aims to shed light on what Sub-1GHz wireless connectivity is, its highlights, target applications, and superior Sub 1G modules available in the market today.

What Is Sub-1GHz?

Sub-1GHz refers to radio frequency (RF) communication technologies that operate lower than the 1 GHz spectrum band, typically in the 769 – 935 MHz, 315 MHz and 468 MHz frequency range.

Unlike WiFi and Bluetooth wireless communication, which both use the same 2.4 GHz band everywhere in the world, the actual frequency bands used for Sub-GHz networking are different in different frequency parts of the world. North America and Australia use 915 MHz as the center frequency whereas Europe uses 868 MHz. The 433 MHz licensed spectrum is free-utilized widely around the world.

Figure1 Free ISM Sub-1GHz band in the world (Source TI.com)

Compared with the 2.4 GHz band, this spectrum band below 1 GHz is more particularly outstanding for RF IoT applications than its competing technologies WiFi and Bluetooth.

Why Are Sub-1GHz RF Favored over 2.4 GHz RF for IoT Applications?

Sub-1GHz radios offer several benefits over 2.4 GHz wireless standards for Internet of Things applications.

Figure2 Why Sub-1 GHz(Source rfstariot.com)

• Longer Range: The lower radio frequency used by Sub-1GHz enables signals to travel farther and penetrate obstacles more effectively compared to higher frequency counterparts. Sub-1GHz signal can easily reach several hundreds of meters indoors and depending on the conditions, several kilometers outdoors; whereas, the maximum range of WiFi or Bluetooth 2.4 GHz wireless transmitter can be up to 200 meters indoors and 400 meters outdoors. This makes it ideal for such applications requiring long-range wireless connectivity, even in challenging environments.

• Lower Power Consumption: Sub-1GHz modules with a coin cell battery typically consume less power than higher frequency alternatives, making it well-suited for battery-powered devices or applications where power consumption is crucial, eg. IoT sensor devices.

• Less Interference: The 2.4 GHz spectrum is crowded and subject to significant interference from Wi-Fi devices, Bluetooth nodes, PC peripherals, and so on. However, Sub-1GHz signals penetrate concrete, walls, and objects more effectively because of their lower-frequency ISM bands and fewer existing applications. So, you can get robust and reliable wireless connectivity in harsh environments. This quality makes Sub-1GHz RF widely applied in home automation, smart agriculture, building & industrial control, and other fields with dense obstacles.

Top 5 Wireless Sub 1G RF IoT Applications

The highlights of Sub-1GHz frequencies mentioned above make Sub-1GHz solutions highly appealing to end users who seek reliable, out-reaching range wireless connections with long battery lifetimes. Here are the top 5 wireless Sub-1GHz RF IoT applications as follows:

Figure3 Top 5 Wireless Sub 1G RF IoT Applications (Source rfstariot.com)

1. Smart Metering and Smart Grids: Sub-1GHz enables reliable and cost-effective wireless communication between utility companies and smart meters, facilitating remote monitoring and management of energy efficiency.
2. Industrial Control: With its extended transmission range and strong penetration capabilities, Sub-1GHz is well-suited for wireless sensor networks in industrial automation systems, providing seamless communication across large factory floors and manufacturing plants.
3. Home Automation: Featuring a long battery lifetime of up to 10 years, the Sub-1GHz module is used in home automation systems to connect various smart devices, such as smart locks, thermostats, and security systems, enabling centralized control and monitoring.
4. Smart Agriculture: Sub-1GHz technology is widely used in precision agriculture, facilitating the deployment of wireless sensor networks for monitoring various environmental parameters across spread-out areas. These parameters include soil moisture, temperature, track activity, such as animal movement, crop growth, and other values.
5. Smart Cities: Sub-1GHz RF's long-range capabilities make it suitable for covering expansive urban areas efficiently, for example, lighting control, air control, parking management systems and more smart city applications.

Available High-Performance Sub-1G Modules

The Sub-1GHz frequency band has gained popularity for IoT applications due to its long range and strong penetration. RF-star, a world-leading wireless module manufacturer has developed Sub-1GHz modules and such IoT applications based on Texas Instruments CC1310, CC1312R, CC1352R, CC1352R7, CC1352P, CC1352P7 SoCs.

The CC1310 module named RF-SM-1077B1 can cover popular frequencies like 868 MHz, and 915 MHz, while RF-SM-1077B2 supports 433 MHz and 470 MHz transceivers and receivers.

More advanced TI Sub-1GHz versions are CC1312R modules because of their rich resources in RAM and flash, and Wi-SUN protocol. RF-SM-1277B1 and RF-SM-1277B2 modules have ready samples.

The CC1352P RF-TI1352P1 module, CC1352P7 RF-TI1352P2 module and CC1352R RF-TI1352B1 module support multi-protocol, eg. Zigbee, Bluetooth 5.1 Low Energy, Thread, Wi-SUN, etc. They are called multi-band Sub-1GHz and 2.4 GHz wireless modules featuring different antennas.

These Sub-1G modules typically feature low-power RF transceivers and receivers, making them suitable for high-sensitivity and long-range wireless communication.

Conclusions

Sub-1GHz wireless connectivity is a robust and versatile technology offering long-range, strong penetration, and low power consumption. Its applications span across various areas, including smart metering, industrial control, home automation, and smart agriculture and cities. With numerous popular Sub-1GHz modules available in the market, developers and companies can leverage this technology to create innovative and reliable wireless IoT solutions to meet a variety of needs. As wireless communication is evolving rapidly, Sub-1GHz is poised to play an increasingly vital role in the Internet of Things (IoT) and other wireless applications.