What Is Sub-GHz Wireless Communication in IoT?
- Nguyen Vinh Loc
- Oct 28, 2020
- 12 min read
“How far can a wireless signal really travel?” — that’s the question that troubles every engineer working with wireless transmission systems. When building an IoT network, the answer often depends on one crucial decision: choosing the right frequency band.
Most wireless developers must decide between two ISM (Industrial, Scientific, and Medical) band options — 2.4GHz or Sub-GHz (below 1GHz). This choice directly impacts key performance factors such as transmission range, energy consumption, data rate, antenna size, and network scalability.
Technologies like Wi-Fi®, Bluetooth® Smart, and ZigBee®, which operate at 2.4GHz, have become dominant in short-range communication. However, for applications that only need low data throughput but high reliability — such as smart agriculture, smart metering, and smart buildings — Sub-GHz systems deliver clear advantages.
By operating at lower frequencies, Sub-GHz wireless technology offers longer transmission distances, lower power usage, and better signal penetration through obstacles like walls or foliage. This makes it an ideal choice for large-scale IoT deployments that need to send small packets of data efficiently over kilometers.
In the following sections, we’ll explore the core characteristics, performance benefits, and real-world applications of Sub-GHz wireless technology — and why it is shaping the next generation of long-range, low-power IoT communication.
What Is Sub-GHz Wireless Technology?
Sub-GHz refers to wireless communication technologies that operate at frequencies below 1 gigahertz (GHz) — typically around 433MHz, 868MHz, or 915MHz, depending on the region. The term “Sub-GHz” literally means “below one gigahertz.”
Unlike 2.4GHz technologies such as Wi-Fi® or Bluetooth®, Sub-GHz systems transmit signals using longer wavelengths. These longer wavelengths can travel farther, penetrate obstacles more effectively, and consume less power — making them ideal for IoT applications that require both range and efficiency.
Frequency Allocation Around the World
Different regions allocate distinct license-free ISM frequency bands for Sub-GHz communication:
These ISM (Industrial, Scientific, and Medical) bands are unlicensed, meaning devices can operate freely as long as they comply with local regulations on output power and duty cycle. This flexibility has made Sub-GHz one of the most widely adopted frequency ranges for low-power IoT communication.
How Sub-GHz Wireless Works
Sub-GHz communication uses radio waves in the lower spectrum of the electromagnetic range. These signals are transmitted between a transmitter (sensor or end node) and a receiver (gateway or base station) without the need for physical cabling.
In a typical IoT setup:
End devices (sensors) collect measurements such as temperature, humidity, or pressure.
These devices transmit data packets periodically or on-demand through a Sub-GHz radio module.
The receiver collects the signals and forwards the data to control systems such as PLCs, HMIs, SCADA platforms, or IoT gateways.
Because the radio waves at lower frequencies can propagate through walls, vegetation, and urban obstacles, Sub-GHz networks achieve a communication range of several kilometers — even under challenging industrial conditions.
Key Advantages at a Glance
Long transmission range – up to several kilometers outdoors.
Low energy consumption – ideal for battery-powered devices lasting up to 10 years.
Strong signal penetration – less attenuation through obstacles.
Lower interference – operates below crowded 2.4GHz spectrum.
Cost-effective deployment – fewer repeaters or base stations required.
These advantages explain why Sub-GHz has become a cornerstone technology for industrial IoT, smart metering, and agricultural automation — where devices often need to communicate over large areas with minimal maintenance.
Advantages of Sub-GHz Wireless Systems
When designing an IoT network, engineers often face trade-offs between range, power consumption, reliability, and cost. Sub-GHz wireless technology stands out because it performs exceptionally well across all these factors — especially in industrial, agricultural, and smart-city applications that demand stable long-range communication.
Long Transmission Distance
One of the most striking advantages of Sub-GHz technology is its long communication range. A typical Wi-Fi® router can reach about 50 m indoors and 100 m outdoors, while Bluetooth® usually works within 10 m. In contrast, Sub-GHz systems can transmit over hundreds of meters indoors and several kilometers outdoors, depending on antenna type, line-of-sight conditions, and terrain.
Because Sub-GHz signals use lower frequencies and longer wavelengths, they can propagate through walls, trees, and even concrete structures more effectively than 2.4 GHz signals.This characteristic makes them ideal for dense urban areas or industrial plants where multiple obstacles often block higher-frequency waves.
Sub-GHz transceivers also offer various modulation schemes — such as narrowband and ultra-narrowband — that maximize coverage and reduce noise. These techniques are widely used in smart-metering, alarm systems, and environmental monitoring, where data packets are small but reliability is critical.
Ultra-Low Power Consumption
Power efficiency is another major advantage of Sub-GHz systems. For IoT networks with thousands of distributed devices, replacing or recharging batteries is both costly and time-consuming. Sub-GHz modules address this challenge through optimized duty cycles and sleep modes that dramatically reduce power draw.
Typical Sub-GHz MCUs, such as TI’s CC1310, consume only 5.5 mA in receive mode and 22.6 mA in transmit mode at +14 dBm.
The built-in ARM® Cortex®-M3 core can run at low clock speeds while keeping power below 51 µA/MHz.
In standby states, consumption drops to around 0.6 µA, while memory and sensor data are retained.
This efficiency allows battery-powered devices — such as temperature, flow, or pressure sensors — to operate for up to 10 years on a single coin cell or through energy-harvesting methods like solar power.
Strong Resistance to Interference
Most consumer wireless devices — Wi-Fi®, Bluetooth®, ZigBee®, and many cordless phones — operate at 2.4 GHz, a band that is heavily congested. As device density increases, signal collisions and retransmissions become common, degrading throughput and reliability.
Sub-GHz communication avoids these issues by operating in a less crowded spectrum, resulting in:
Lower packet loss and fewer retransmissions
More stable links even in industrial environments
Scalable networks that can connect hundreds or thousands of end nodes
This robustness is crucial for mission-critical applications like industrial automation, public infrastructure monitoring, and disaster alert systems, where every data packet counts.
Low Deployment and Operating Cost
From a system-integration perspective, Sub-GHz networks offer cost-effective scalability.Long-range coverage means fewer gateways or repeaters are required, and battery-powered nodes eliminate wiring costs entirely.
Moreover, Sub-GHz networks often comply with open standards such as IEEE 802.15.4g, wM-Bus, and 6LoWPAN, which ensure interoperability and fast development cycles.These standardized ecosystems shorten time-to-market and reduce total cost of ownership (TCO) for IoT solutions in factories, utilities, and smart infrastructure.
Comparison: Sub-GHz vs 2.4 GHz Protocols
Choosing between Sub-GHz and 2.4 GHz technologies is one of the most important design decisions in any IoT system.
While 2.4 GHz protocols such as Wi-Fi®, Bluetooth® Smart, and ZigBee® dominate consumer and office environments, Sub-GHz technologies excel in industrial, agricultural, and infrastructure applications that require longer range, higher reliability, and lower power consumption.
Frequency and Bandwidth
2.4 GHz band: offers high data rates (up to hundreds of Mbps) but suffers from higher attenuation and congestion.
Sub-GHz band: operates at lower frequencies (typically 433, 868, 915 MHz), providing wider coverage but lower throughput — usually sufficient for sensor data and telemetry.
Lower frequencies also mean wider signal wavelengths, which allows Sub-GHz signals to bend around obstacles and travel farther before significant loss occurs.
Data Rate vs Range Trade-off
This comparison illustrates a fundamental rule in wireless communication:
Higher frequency = higher speed but shorter range; lower frequency = lower speed but greater coverage.
Interference and Reliability
The 2.4 GHz band is shared among Wi-Fi routers, Bluetooth devices, microwave ovens, and even cordless phones, making it prone to signal collisions and packet loss. Sub-GHz networks, by contrast, operate in a cleaner spectrum, reducing retransmissions and increasing communication stability — especially in dense industrial sites or urban IoT deployments.
Furthermore, the narrowband modulation schemes used in Sub-GHz (such as FSK, GFSK, or LoRa) are inherently resistant to noise, allowing stable operation even at long distances or in RF-noisy environments.
Energy Efficiency
Sub-GHz devices transmit at lower data rates and can remain asleep for extended periods, waking only to send short bursts of data.This architecture significantly reduces average current consumption, allowing small batteries to last for years rather than months.
In contrast, 2.4 GHz devices (especially Wi-Fi®) maintain active connections, which consume far more energy — unsuitable for battery-powered or remote IoT nodes.
Scalability and Network Architecture
Sub-GHz technologies support flexible network topologies such as star, mesh, or point-to-point, adapting to different deployment needs.Because the signals can cover large areas, one Sub-GHz gateway can manage hundreds of end devices, simplifying infrastructure.
Meanwhile, 2.4 GHz networks require more repeaters or routers to extend coverage, which increases cost and maintenance complexity.
Hardware Ecosystem and Manufacturers
Behind every efficient Sub-GHz network lies a robust ecosystem of semiconductor manufacturers and hardware development platforms. These solutions make it easier for engineers to design, test, and scale IoT systems that meet demanding industrial requirements for reliability, energy efficiency, and long-range connectivity.
Leading Sub-GHz Solution Providers
Several global technology companies have developed integrated chipsets and modules for Sub-GHz wireless communication:
Texas Instruments (USA) – Provides the renowned SimpleLink™ Sub-GHz platform with development kits, MCUs, and RF transceivers designed for low-power, long-range IoT.
Silicon Labs (USA) – Offers highly integrated Sub-GHz transceivers optimized for smart metering, building automation, and security systems.
Renesas (Japan) – Focuses on industrial-grade Sub-GHz solutions with excellent noise immunity and extended temperature range.
Each manufacturer contributes unique strengths — from TI’s developer-friendly toolchains to Renesas’s reliability in harsh environments — forming a diverse ecosystem that supports innovation across industries.
Texas Instruments SimpleLink™ CC1310 LaunchPad
A standout example in the Sub-GHz domain is Texas Instruments’ LAUNCHXL-CC1310 kit — a compact, high-performance development board built for long-range, low-power wireless applications.
Key Features:
Sub-GHz radio transceiver with excellent receiver sensitivity for extended communication distance.
32-bit ARM® Cortex®-M3 processor running at 48 MHz for flexible application control.
Ultra-low-power sensor controller that can collect analog or digital data autonomously while the main system sleeps.
Power management system capable of deep-sleep currents below 1 µA while retaining memory.
Flexible software ecosystem through the SimpleLink™ CC13x0 SDK, which includes RF drivers, power-management modules, and example projects.
This kit is part of the SimpleLink MCU platform, allowing developers to quickly prototype IoT products and connect them seamlessly with other wireless standards — all from a unified development environment.
Development Benefits
For engineers and integrators, using a mature Sub-GHz platform like TI’s CC1310 or Renesas’s RA series offers several advantages:
Reduced time-to-market thanks to pre-certified radio modules and comprehensive SDKs.
Simplified prototyping via LaunchPad connectors and BoosterPack™ expansion modules.
Reliable RF performance with built-in power-amplifier control and low-noise design.
Long-term component availability — critical for industrial and infrastructure deployments.
Such development ecosystems lower technical barriers, enabling organizations like Daviteq to design high-performance wireless sensors that meet global industrial standards.
Sub-GHz Sensors and Network Architecture
At the heart of every Sub-GHz IoT system are wireless sensors and the network infrastructure that connects them. These components work together to collect environmental or process data, transmit it efficiently, and deliver it to higher-level systems for analysis and control.
How a Sub-GHz Wireless Sensor Works
A typical Sub-GHz wireless sensor consists of two integrated parts:
Sensor Module / Transducer Element – measures a specific variable such as temperature, humidity, pressure, flow, or gas concentration.
Wireless Transmitter Module – encodes and sends the sensor’s readings through the Sub-GHz radio channel.
Both elements are powered by a small battery or an energy-harvesting source (solar, vibration, etc.). Because Sub-GHz communication is optimized for ultra-low duty cycles, the transmitter remains in sleep mode most of the time and wakes periodically to send data packets or respond to gateway commands.This approach minimizes energy use, enabling multi-year operation (up to 10–20 years) depending on transmission frequency and sensor type.
Receiver and Gateway Operation
On the network side, a Sub-GHz receiver or gateway performs three key functions:
Signal Reception – captures the transmitted RF packets via an antenna.
Data Processing – demodulates and decodes the signal, verifying data integrity.
Output and Integration – transfers processed data to industrial systems via ModbusRTU, PLC, HMI, SCADA, or IoT platforms for monitoring and analytics.
With clear line-of-sight between antennas, the receiver’s coverage can reach several kilometers. Even with partial obstruction, Sub-GHz links remain stable thanks to their superior wall and foliage penetration compared to higher-frequency technologies.
Network Topology and Architecture
Sub-GHz sensor networks are often organized in star topology — multiple sensors communicate directly with a central receiver or base station.This simple architecture minimizes latency and power consumption while ensuring reliable data aggregation. Depending on the application, networks can also adopt other configurations:
Point-to-Point: direct communication between two nodes for dedicated measurements.
Mesh or Clustered Star: extended coverage for large-area monitoring such as factories or farms.
Hybrid Topologies: combine multiple gateways for redundancy and scalability.
Such flexibility allows Sub-GHz systems to be rapidly deployed without signal or power cables, avoiding downtime during installation — a critical advantage for industrial facilities, buildings, or utilities that must remain operational.
Industrial and Smart-Infrastructure Use Cases
Sub-GHz wireless sensor networks are now integral to:
Smart Energy Systems: electricity, water, gas, and heat metering.
Building Management Systems (BMS): HVAC monitoring, fire safety alerts, occupancy sensing.
Industrial Automation: remote equipment status and process control.
Smart Agriculture and Fisheries: soil moisture, irrigation control, water quality tracking.
Environmental and Security Monitoring: pollution sensors, disaster early warning, perimeter detection.
By integrating sensors, gateways, and analytics platforms, Sub-GHz networks deliver in-time data that supports predictive maintenance, efficient resource use, and safer operations.
Real-World Applications of Sub-GHz Technology
Thanks to its combination of long range, low power, and strong interference immunity, Sub-GHz wireless technology has become a backbone for modern IoT systems. It is particularly valuable in sectors where devices are distributed across wide areas or installed in environments with heavy signal obstruction — such as factories, farms, or smart cities.
Below are several industries where Sub-GHz technology is driving real transformation — each illustrated with a real device from Daviteq.
Smart Energy and Utility Metering
Sub-GHz communication is widely adopted in electricity, water, gas, and heat metering systems. These meters periodically send small packets of consumption data to a central gateway, enabling utilities to:
Perform remote meter reading without on-site visits.
Detect anomalies such as leaks or unauthorized usage.
Reduce operational costs and improve billing accuracy.
Example device: the Daviteq Sub-GHz Ex d Process Pressure Sensor (SKU WS433EX-PPS) is built for hazardous zones (Zone 1/2) and uses Sub-GHz 433 MHz wireless to transmit high-accuracy pressure data.
Building Management and Automation
In modern Building Management Systems (BMS), Sub-GHz sensors are used for:
Monitoring temperature, humidity, air quality, and occupancy.
Controlling lighting and HVAC systems automatically based on real-time data.
Enhancing energy efficiency without requiring rewiring or downtime.
Example device: the Daviteq Sub-GHz LiDAR People Counter (WS433-LPC) uses Sub-GHz wireless connectivity to report occupancy data over long distances and ultra-low power — ideal for multi-floor buildings or large retail spaces.
Industrial Automation
Factories and production sites often need wireless monitoring of remote or rotating equipment. Sub-GHz sensors enable:
Condition-based monitoring for temperature, vibration, or pressure.
Predictive maintenance, helping avoid unplanned downtime.
Easy integration with PLC, HMI, or SCADA systems for centralized control.
Example device: the Daviteq Sub-GHz Tower Vibration Sensor (WS433-TVS) monitors vibrations, tilt and wind speed indicator of telecom/electrical towers with Sub-GHz wireless for long-distance data link and low-maintenance operation.
Smart Agriculture and Fisheries
In agriculture, Sub-GHz wireless systems provide the long-range coverage needed for large farms and greenhouses. Typical applications include:
Soil moisture and temperature monitoring for precise irrigation control.
Weather and environmental sensing to optimize planting schedules.
Water quality and feed monitoring in aquaculture or fisheries.
Example device: the Daviteq Sub-GHz Gas Detecting Sensor (WS433-G4) supports multiple gas types (CO, NO₂, NH₃…) and Sub-GHz wireless for remote industrial facilities, which can be adapted in agriculture / fishery settings for air-quality monitoring.
Environmental Monitoring and Public Safety
Sub-GHz networks play a critical role in smart city and environmental systems, enabling:
Air quality and CO₂ monitoring for pollution control.
Flood and disaster warning through distributed water-level sensors.
Crime detection and perimeter monitoring in security systems.
Their resilience and wide-area coverage make Sub-GHz ideal for mission-critical data collection, even in remote or rural regions.
Energy efficiency, long transmission range, and high reliability are the key factors shaping the future of IoT connectivity — and Sub-GHz wireless technology embodies all of them. By operating at frequencies below 1 GHz, Sub-GHz systems deliver outstanding performance where other wireless protocols fall short: covering kilometers of distance, consuming minimal power, and maintaining stable links even in complex industrial or urban environments.
As the IoT ecosystem expands into millions of connected sensors, Sub-GHz communication provides a cost-effective, scalable foundation for diverse applications — from smart factories and energy infrastructure to agriculture, smart cities, and environmental monitoring.Its low power profile and robust signal penetration make it a sustainable choice for long-term industrial deployments.
At Daviteq, we are proud to be among the pioneers in developing Sub-GHz-based wireless sensor solutions for global industries. Our portfolio — including products such as the Sub-GHz Tower Vibration Sensor, Sub-GHz Gas Detecting Sensor, Sub-GHz LiDAR People Counter, and Sub-GHz Ex d Process Pressure Sensor — demonstrates how Vietnamese innovation can deliver world-class performance, reliability, and energy efficiency. With decades of expertise in industrial automation and wireless communication, Daviteq continues to empower enterprises worldwide to build smarter, safer, and more sustainable operations.
Comments