Will Ultra-Wideband (UWB) replace Bluetooth Low Energy Beacons when it comes to indoor positioning?
Which technology to use today for indoor location?
We discuss the pros and cons of indoor location using Ultra-Wideband and Bluetooth Low Energy
In September 2019, Apple announced that the iPhone 11 would include a “U1” chip with Ultra-Wideband (UWB) technology.
Just like Bluetooth, the Ultra-Wideband technology gives devices the ability to determine each other's location when they're in close proximity. It means it could be used for a variety of location-based services, such as wayfinding inside venues and contextual notifications.
If you operate a large venue such as an airport, a shopping mall or a corporate campus, you may be thinking of installing a real-time location system in your organisation - or you might even already have indoor location enabled in your venue.
Should you use Ultra-Wideband as a technology for indoor location? Will Ultra-Wideband replace Bluetooth and other indoor location technologies?
Which indoor positioning technologies are available today?
When out and about, GPS is used to locate objects, destinations and people. Indoors, however, this is much more difficult. GPS relies on signals sent by GPS satellites orbiting the earth. Once you go inside a building or venture underground, that signal is distorted, as explained in our post on how GPS works and its efficacy indoors. The result is a significant drop in accuracy when the user enters a building. That is where the indoor positioning system comes in.
In the absence of GPS, indoor positioning systems utilize several different techniques, each with slightly different results. The most common ones are Bluetooth Low Energy and Wi-Fi. Moreover, new techniques are being developed, such as Ultra-Wideband and Bluetooth Low Energy 5.1.
In this blog post, we focus on two indoor positioning technologies: Bluetooth Low Energy and Ultra-Wideband. We explain the difference between the two technologies when it comes to indoor location inside buildings.
Indoor Positioning using Bluetooth Low Energy (BLE Positioning)
Bluetooth Low Energy Beacons are small battery powered devices that connect to Bluetooth-enabled devices like smartphones. They use Bluetooth Low Energy (BLE) to broadcast a signal for up to 70 meters. The user’s device, which may be a smartphone or a tablet, picks up these Bluetooth signals and use their strength to determine the distance from the beacon, usually in conjunction with an app on the device. The mechanism is very similar to lighthouses, which emit a light that is picked up by passing ships.
As the name suggests, Bluetooth Low Energy is extremely power efficient. A phone’s battery drain is less than 1% because of nearby beacons. Beacons are very efficient and cost-effective. They can be used inside WiFi access points or lighting infrastructure, or they can be powered by button cell batteries. Maintenance is often an infrequent necessity, making them ideal for high traffic venues.
Unlike any other positioning technique, beacons provide background capabilities, which enables positioning even when the user is not using the app. For instance, if a visitor in a supermarket has a phone in their pocket, the retailer can still enable geofencing and contextual notifications, provided that the user has given prior consent.
The benefits of Bluetooth Beacons for Indoor Positioning:
- Compatible with both Android and iOS
- Low energy consumption - they don’t drain battery on the user’s phone
- Low deployment cost
- Low maintenance - batteries don’t need to be replaced often
- Provides background tracking capabilities, even when the app is closed
- Widespread adoption - almost all modern smartphones have Bluetooth enabled, meaning no additional infrastructure beyond BLE beacons is required to enable indoor positioning
Additional benefits when using Bluetooth Beacons in combination with Pointr’s Deep Location® technology:
- High positioning accuracy of <3 meters when combined with other sensors
- Works offline with Deep Location®, even where there is no data connection
It is worth noting that a new Bluetooth Low Energy standard called BLE 5.1 is already released for hardware manufacturers. No one knows how long it will take before this is available on our phones but once it is, the accuracy of indoor positioning with beacons will go below 1 meter.
Want to learn everything there is to know about indoor positioning? Download our guide.
Indoor positioning using ultra-wideband (UWB)
What is ultra-wideband?
Ultra-wideband (UWB) is a radio technology that uses low power consumption to achieve high bandwidth connections.
UWB vs Bluetooth (BLE) - what are the core differences?
- UWB has a greater range - around 300 meters compared to 100 meters for Bluetooth - though in practice, both technologies have similar ranges in which they're truly effective
- UWB is capable of transmitting more data, particularly compared to Bluetooth Low Energy
- Bluetooth-enabled devices are far more common, including almost all modern smartphones. UWB is found only in select smartphone models and specialist devices such as AirTags
How does UWB indoor positioning work?
Ultra-wideband offers the potential for positioning technology thanks to two key signals - “Time of Flight” (known as ToF) and “Time Difference of Arrival” (TDoA). By algorithmically combining these two signals, systems are able to calculate a user’s position, sometimes with a higher degree of accuracy than even Bluetooth low energy (BLE) can.
After a slow roll out, UWB is now available across numerous mobile devices, increasing its viability as an indoor positioning technology. All iPhones from the iPhone 11 now support UWB, as do the Google Pixel 6 Pro and 7 Pro, along with several newer models of Samsung.
On paper, ultra-wideband sounds like an exciting future technology to watch. At Pointr, we will be supporting ultra-wideband if and when the time is right. However, we don't expect a quick transition due to several challenges, which we highlight below:
3 drawbacks of UWB positioning and localization
Lack of existing infrastructure
Even though ultra-wideband seems superior to Bluetooth positioning, there is no UWB infrastructure in place today. It requires antennas to be installed in the corners of the venue before indoor positioning with UWB can be enabled. Hardware companies have invested a lot of effort in Bluetooth Low Energy deployment so it’s likely they will stick to Bluetooth technology.
Ultra-wideband adoption currently lags far behind Bluetooth
While UWB has begun to appear on certain devices, it's far from common. This means that if you're a business owner looking to enable an indoor positioning system, attempting to do so with UWB will mean excluding the majority of your potential users. Even as smartphone manufacturers begin to implement UWB within their new devices, between those who have yet to add it to their future device roadmaps and the time it takes for legacy devices to drop out of circulation, it will take at least several years before UWB approaches the ubiquity levels required to make it a viable alternative to Bluetooth for a consumer- or public-facing IPIN system.
Improved location accuracy with BLE 5.1
Given that the new Bluetooth Low Energy 5.1 standard is coming, UWB's additional precision might not be that useful if Bluetooth Low Energy already provides improved accuracy, which would be sufficient for most applications. For applications where precision to a centimeter is needed, such as warehouse tracking, specialized hardware like ultra-wideband may be deployed.
Is UWB or Bluetooth best for an indoor positioning system?
Pointr constantly invests in R&D to ensure we stay well positioned to bring you the best in indoor positioning technology. Pointr’s Deep Location® technology utilizes a combination of sensors and machine-learning algorithms to bring accurate indoor positioning to airports, large retail spaces, smart workplaces, hotels & resorts and more.
Our algorithms are agnostic to technology and we are already testing ultra-wideband technology. We will launch updated software development kits (SDKs) if and when we start seeing adoption of this technology, as we keep up to date with what consumers demand and use in the market today.
We believe that ultra-wideband is a technology to watch for indoor positioning. It is currently at a disadvantage of not being handled by today’s smartphones and mobile devices, but if it does reach a level of commonality that means it becomes a viable alternative to Bluetooth in the coming years, we'll be ready and waiting for businesses that want to leverage it.
Interested in indoor location?
At Pointr, we help you get the right location technology for your venue. We work with large building operators such as airports, shopping malls, hotels and corporate campuses to enable location-based services and analytics. We are hardware agnostic, which means we are not biased towards a technology or another. We analyze your needs and we decide which technology makes sense for you.