What is HaLow?
There’s a new wireless networking protocol in town and it comes to bring connectivity to the Internet of Things. Wi-Fi HaLow (pronounced “HAY-low”) is a marketing name used for products that utilize the IEEE 802.11ah wireless technology, which offers longer range and lower power connectivity than traditional WiFi-certified products.
Wi-Fi HaLow is the latest specification from the Wi-Fi Alliance looking to expand the range of Wi-Fi’s connectivity options. Wi-Fi HaLow will be able to easily work through walls and large barriers because of the propagation capabilities of low-frequency radio waves, as it will operate in the unlicensed wireless spectrum below 1GHz. HaLow’s range will be nearly double the range of today’s Wi-Fi, with estimates extending as high as a whopping 3,280 feet.
HaLow is designed for the Internet of Things, designed to connect multiple devices wirelessly, over extended distances and using lower power.
- 802.11ah HaLow: for low data rate, long-range sensors and controllers.
- 802.11af: for similar applications to 802.11ah. This network option relies on unused TV spectrums instead of 2.4 GHz or 5 GHz bands for transmission.
- 802.11ad: for multigigabit speeds (sans wires) and high-performance networking.
A History of Past & Current 802.11 Amendments.
802.11a (1990): “WiFi A”—also known as the OFDM (Orthogonal, Frequency Division Multiplexing) waveform—was the first amendment, and it came two years after the standard was complete. This amendment defined 5 gigahertz band extensions, which made it more flexible (since the 2.4 GHz space was crowded with wireless home telephones, baby monitors, microwaves, and more).
802.11b (2000): As one of the first widely used protocols, “WiFi B” had an improved range and transfer rate, but it is very slow by today’s standards (maxing out at 11 mbps). 802.11b defined 2.4 GHz band extensions. This protocol is still supported (since 80% of WiFi runs off of 2.4 GHz), but the technology isn’t manufactured anymore because it’s been replaced by faster options.
802.11g (2003): “WiFi G” came onto the market three years after B, and it offered roughly five times the transfer rate (at 54 mbps). It defined 2.4 GHz band extensions at a higher data rate. The primary benefit it offered was greater speed, which was increasingly important to consumers. Today, these speeds are not fast enough to keep up with the average number of WiFi-enabled devices in a household or a strong wireless draw from a number of devices.
802.11n (2007): “WiFi N” offered another drastic improvement in transfer rate speed—300-450 mbps, depending on the number of antennas—and range. This was the first main protocol that operated on both 2.4 GHz and 5 GHz. These transfer rates allow large amounts of data to be transmitted more quickly than ever before.
802.11ac (2013): In 2013, “WiFi AC” was introduced. AC was the first step in what is considered “Gigabit WiFi,” meaning it offers speeds of nearly 1 gbps, which is equivalent to 800 mbps. That’s roughly 20 times more powerful than 802.11n, making this an important (and widely used) new protocol. AC runs on a 5 GHz band, which is important—because it’s less widely used, you’ll have an advantage as far as high online speeds are concerned, though the higher frequency and higher modulation rate mean the range is more limited.
802.11ah: – is 900 megahertz WiFi, which is ideal for low power consumption and long-range data transmission. It’s earned the nickname “the low power WiFi” for that very reason.
802.11af: – utilizes unused television spectrum frequencies (i.e., white spaces) to transmit information. Because of this, it’s earned the nickname “White-Fi.” Because these frequencies are between 54 MHz and 790 MHz, AF can be used for low power, wide-area range, like AH.
802.11ad: – couldn’t be further from AH. While AH is a future LPWAN option, AD is ideal for very high data rate, very short range communications.
AD WiFi – previously known as WiGig because of it’s predecessor 802.11ac—separates itself from the 2.4 GHz and 5 GHz bands and operates on a 60 GHz band. This space is completely free and open, which helps it achieve speeds that are 50 times faster than WiFi N. And while AH uses 900 MHz, AD uses 60 GHz. To put that into perspective, 60 GHz is equivalent to 60,000 MHz.
Why A New Standard?
The increasing number of devices that need connectivity means that traditional WiFi networks can’t keep up. Also the Internet of Things, smaller smart and wearable devices that need to stay in touch but with infrequent communication are crying out for reliable, effective, low cost, mains free connectivity that can reach them wherever they are, even behind thick walls or on the move. HaLow provides that, and more besides.
What frequency is Wi-Fi HaLow?
Wi-Fi HaLow sits in the 900MHz band, designed to offer better penetration through walls, as well as nearly doubling the range compared to existing Wi-Fi connections. HaLow will also support IP-based connections to the cloud, for example to make your smartwatch independent.
You’ll have to have IEEE 802.11ah compatible hardware of course, and it’s likely that it will support existing 2.4 and 5GHz bands as normal too.
How Wi-Fi HaLow Differs from Previous Wi-Fi Standards?
HaLow extends Wi-Fi into the 900 MHz band, a part of the electromagnetic radiation spectrum that is well-suited for small data payloads and low-power devices. This lower part of the spectrum is also able to penetrate walls and other physical barriers and has better range than the 2.4GHz and 5 GHz Wi-Fi bands.
Wi-Fi HaLow is also the first Wi-Fi specification to operate in frequency bands below one gigahertz (900 MHz), and it has a range of nearly twice that of other Wi-Fi technologies. In addition to its extended range capabilities, Wi-Fi HaLow is also able to penetrate walls and other barriers considerably better than previous Wi-Fi standards.
Why Does It Need Less Power?
It needs less power because instead of transferring large amounts of data quickly like your current business Wi-Fi connection, it sends data in periodic and concentrated bursts.
The long range and low power requirements means that WiFi HaLow devices will be able to operate without mains power and without the need for a powerful battery.
As well as being useful for the small smart devices, HaLow’s background WiFi blackspot-filling function and buffering-busting properties could have a positive impact on ‘Bring Your Own Device’ (BYOD) battery life.
How will Wi-Fi HaLow be used?
It’s likely to find its way into things like wearable technology, so your fitness band or smartwatch could use Wi-Fi HaLow instead of, or as well as, Bluetooth LE.
The use cases that the Wi-Fi Alliance have outlined include smarthome, connected cars, healthcare and various other industrial applications. For example, multiple sensors could be connected over Wi-Fi HaLow in your smarthome.
HaLow clearly has so many potential connectivity and cost saving applications across healthcare, industrial, retail, agriculture and other industries. It could become a valuable part of large-scale private and public facilities, and even for connected cars.
In all these cases it’s likely to be low-bandwidth devices, providing a trickle of information, rather than a flood.
When are Wi-Fi HaLow devices likely to appear?
Not for some time. This is just first stage in making the certification official. Devices will need to be developed and tested, so you’re unlikely to see anything in the immediate future.The Alliance expects to launch a certification process for Wi-Fi HaLow products in 2018.