Wi-Fi HaLow is a wireless networking technology that operates in the sub-1 GHz spectrum, offering longer range, lower power consumption, and higher reliability than conventional Wi-Fi networks. Wi-Fi HaLow is designed to meet the needs of the Internet of Things (IoT), enabling connectivity for a variety of devices and applications in industrial, agricultural, smart building, and smart city environments.
What is Wi-Fi HaLow?
Wi-Fi HaLow is a Wi-Fi Alliance designation for products using IEEE 802.11ah standard, which was published in 2017. Wi-Fi HaLow uses license-exempt bands below 1 GHz, such as the 900 MHz band, to provide extended-range Wi-Fi networks, compared to conventional Wi-Fi networks operating in the 2.4 GHz, 5 GHz and 6 GHz bands. Wi-Fi HaLow can cover a radius of up to one kilometer, depending on the environment and the device characteristics.
Wi-Fi HaLow also benefits from lower energy consumption, allowing the creation of large groups of stations or sensors that cooperate to share signals, supporting the concept of the IoT. Wi-Fi HaLow enables the low power connectivity necessary for applications such as sensor networks, wearables, smart meters, and smart lighting. Wi-Fi HaLow devices can operate for years on a single battery, thanks to predefined wake/doze periods and power-saving mechanisms.
Wi-Fi HaLow is compatible with the existing Wi-Fi infrastructure and can coexist with other Wi-Fi technologies. Wi-Fi HaLow devices can use the same Wi-Fi security protocols, such as WPA3, to ensure data protection and privacy. Wi-Fi HaLow also supports multi-vendor interoperability, easy setup, and seamless roaming, as part of the Wi-Fi portfolio.
Why use Wi-Fi HaLow for IoT deployments?
Wi-Fi HaLow is a promising technology for IoT deployments, as it offers several advantages over other IoT technologies, such as Bluetooth, LoRa, and Zigbee. Some of these advantages are:
- Higher data rates: Wi-Fi HaLow can achieve data rates up to 347 Mbit/s, depending on the channel width, modulation scheme, and spatial streams used. This is much higher than the data rates of other IoT technologies, which are typically in the range of kbit/s to Mbit/s. Higher data rates enable Wi-Fi HaLow to support more demanding applications, such as video streaming, voice communication, and remote control.
- Wider coverage range: Wi-Fi HaLow can extend the coverage range of Wi-Fi networks by operating in the sub-1 GHz spectrum, which has better propagation characteristics than the higher frequency bands. Wi-Fi HaLow can penetrate walls, floors, and other obstacles, and reach remote areas that are not covered by other Wi-Fi networks. Wider coverage range reduces the need for additional infrastructure, such as repeaters and gateways, and lowers the deployment and maintenance costs.
- More robust connection: Wi-Fi HaLow can provide a more robust connection in challenging environments, where there is high interference, noise, or multipath fading. Wi-Fi HaLow uses various techniques, such as channel bonding, beamforming, and diversity, to improve the signal quality and reliability. Wi-Fi HaLow also supports adaptive modulation and coding, which allows the devices to adjust the transmission parameters according to the channel conditions.
- More scalable network: Wi-Fi HaLow can support thousands of devices under a single access point, thanks to the use of Restricted Access Window (RAW) mechanism, which divides the medium access time into slots and assigns them to different groups of devices. This reduces the contention and collision on the air media, and improves the network efficiency and performance. Wi-Fi HaLow also supports relay and mesh capabilities, which enable the devices to extend their reach and coverage by forwarding packets to other devices.
How to use Wi-Fi HaLow for IoT deployments?
Wi-Fi HaLow is a relatively new technology, and there are not many products and devices that support it yet. However, some companies and organizations are developing and testing Wi-Fi HaLow solutions for various IoT applications and scenarios. For example, Morse Micro, a semiconductor company, has demonstrated the use of Wi-Fi HaLow for a video call at a range of 1.8 miles, despite high interference. Another example is the Wi-Fi Alliance, which has conducted field trials of Wi-Fi HaLow for smart agriculture and smart city applications, showing the benefits of long range, low power, and high density connectivity.
To use Wi-Fi HaLow for IoT deployments, one needs to have Wi-Fi HaLow certified devices, which can be identified by the Wi-Fi HaLow logo. Wi-Fi HaLow certified devices are expected to be available in the market in the near future, as the Wi-Fi Alliance has launched the Wi-Fi CERTIFIED HaLow program in 2021, which provides testing and certification for Wi-Fi HaLow products. Wi-Fi HaLow certified devices can be configured and managed using the same tools and methods as other Wi-Fi devices, such as Wi-Fi Protected Setup (WPS), Wi-Fi Easy Connect, and Wi-Fi Easy Mesh.
The following table summarizes some of the key features and specifications of Wi-Fi HaLow, compared to other Wi-Fi technologies.
| Feature | Wi-Fi HaLow | Wi-Fi 4 | Wi-Fi 5 | Wi-Fi 6 |
|---|---|---|---|---|
| Standard | IEEE 802.11ah | IEEE 802.11n | IEEE 802.11ac | IEEE 802.11ax |
| Frequency band | Sub-1 GHz | 2.4 GHz and 5 GHz | 5 GHz and 6 GHz | 2.4 GHz, 5 GHz and 6 GHz |
| Channel width | 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz | 20 MHz, 40 MHz | 20 MHz, 40 MHz, 80 MHz, and 160 MHz | 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 80+80 MHz |
| Modulation scheme | BPSK, QPSK, 16-QAM, 64-QAM, and 256-QAM | BPSK, QPSK, 16-QAM, and 64-QAM | BPSK, QPSK, 16-QAM, 64-QAM, and 256-QAM | BPSK, QPSK, 16-QAM, 64-QAM, 256-QAM, and 1024-QAM |
| Coding rate | 1/2, 3/4, and 5/6 | 1/2, 2/3, 3/4, and 5/6 | 1/2, 2/3, 3/4, and 5/6 | 1/2, 2/3, 3/4, and 5/6 |
| Spatial streams | Up to 4 | Up to 4 | Up to 8 | Up to 8 |
| Data rate | Up to 347 Mbit/s | Up to 600 Mbit/s | Up to 6.9 Gbit/s | Up to 9.6 Gbit/s |
| Range | Up to 1 km | Up to 100 m | Up to 50 m | Up to 50 m |
| Power consumption | Low | Medium | High | High |
