Wi-Fi HaLow runs rings around old-style wireless networks

Getting your Trinity Audio player ready...

Back in 2017, the IEEE published a networking standard that would enable wireless users to do some very clever things, such as connect more than 8000 devices to a single access point. Multiple devices supporting the wireless networking protocol, dubbed Wi-Fi HaLow (802.11ah), are starting to hit the market. And having Wi-Fi that’s accessible from over 1 km away, together with other IoT-friendly features, is getting developers interested.

A quick history of Wi-Fi

Wi-Fi has become the de facto way for a huge number of devices to connect to the internet – so much so that you’ll struggle to find a modern laptop with a built-in wired Ethernet port. And when we’re talking about Wi-Fi, we’re referring to an IEEE wireless Ethernet standard known as 802.11.

Over the years, that standard has evolved to support faster data transmission rates and operate across higher frequency bandwidths. Also, since 2008, the updates have been numbered 4 (802.11n), 5 (802.11ac), and 6 (802.11ax). Wi-Fi 7 was officially certified by the Wi-Fi Alliance on 8 Jan 2024.

However, there’s a trade-off between range and data transmission rate, as home broadband users will be aware of. At 2.4 GHz, the wireless network will probably cover the whole house – unless you’ve got some particularly thick walls in the way. However, at 5 GHz you may need to add a range extender. And by the time you get to the super-high throughput 6 GHz band supported by Wi-Fi 6 and 7, you’ll find that transmission is limited even further.

Wi-Fi HaLow was created to provide a low-power wide area network necessary to support the large-scale deployment of IoT devices – for example, in industrial settings inside and outside of large buildings – while retaining all of the advantages of wireless Ethernet.

Use cases for Wi-Fi HaLow

A great example of how Wi-Fi HaLow wireless networks can benefit warehousing and retail is electronic shelf edge labels. These devices – based on battery-powered LCD or electronic paper screens – can be easily managed via Wi-Fi HaLow, which not only accommodates thousands of connected devices, but also provides energy-efficient networking.

The power-saving nature of Wi-Fi HaLow is well-suited to battery-powered clients, which dramatically broadens the scope of where IoT technology can be deployed. For example, systems could be ideal for agricultural applications, bringing IoT into the field and barn. The wide-area coverage is also well-suited for manufacturing, healthcare, and smart city applications – to list just a few more industrial IoT scenarios.

Taiwan-based AsiaRF has shown how wearable Wi-Fi HaLow gateway devices turn smartphones into walkie-talkies, with numerous industrial use cases. According to the engineers involved in the test, voice communications were clear when participants were stationary and on the move, up to a range of 1.5 km. Morse Micro – a fabless semiconductor start-up – went even further and demonstrated that it was possible to hold a video call between devices at either end of Ocean Beach in California, US, using an 802.11ah wireless network with a 3 km reach.

Also, unlike other long-range wireless networking solutions such as LoRaWAN, Wi-Fi HaLow has all of the authentication and encryption features of a regular Wi-Fi network – such as WPA3-strength passwords, which is a boost for security.

Examples of 802.11ah chipsets –

• Fn-Link 4108E-S Wi-Fi HaLow Module
• TaiXin Semiconductor TXW8301
• Morse Micro MM6108 SoC featuring radio, PHY, and MAC components
• Newracom 802.11 ah Wi-Fi HaLow System-On-a-Chip
• Palma Ceia SemiDesign PCS2100 Wi-Fi HaLow STA modem chip
• Silex Technology SX-NEWAH 802.11ah Wi-Fi Solution for IoT Devices

Circling back to how Wi-Fi HaLow is capable of supporting small battery-powered devices, UK telecommunications training provider MPIRICAL does a good job of explaining what’s happening under the hood. The first option is for the network to store data on behalf of connected devices until they wake up. An alternative is for devices and access points to negotiate a schedule, which means that clients can power down and dramatically extend their battery life.

If all goes to plan, this should be great news for supporting large-scale IoT developments – particularly across relatively inaccessible areas. Having a long battery life could give the go-ahead to projects that were previously thought to be unviable using older Wi-Fi infrastructure.