Asset tracking technologies are the backbone of asset and process management. However, with the overwhelming number of choices for technology, it can be tough to figure out which one best suits your needs.
In this guide, we’ll break down the different types of asset tracking technologies, their benefits, and some key considerations for choosing the right one for your business.
- Ultra-Wideband (UWB)
- Bluetooth Low Energy (BLE)
- Cellular Positioning
- Dual Mode Devices
- Which Asset Tracking Technology Should You Use?
Ultra-Wideband (UWB) is a wireless communication technology that can transmit large amounts of data over a relatively short distance.
UWB tags emit very short information pulses across a wide bandwidth at high frequencies. Signals received by sensors installed on walls or ceilings locate tags reliably with high accuracy in two or three dimensions.
UWB tracking technology can achieve sub-meter accuracy (often to within thirty centimeters) and a range of up to one hundred meters.
UWB tags are active devices and need a power source, typically a battery. However, the batteries can last more than ten years due to low power requirements.
UWB solutions usually draw on measurement methods like AoA, ToF, or TDoA to measure asset location in real-time.
Advantages of UWB
- High accuracy – UWB tracking systems have centimeter-level accuracy in three dimensions, even in cluttered, indoor industrial environments.
- More resistant to multipath interference – Since UWB pulses are very short, reflected pulses are less likely to interfere with the ‘true’ pulse used to measure location.
- Extremely power efficient – Low data rate UWB tags have low duty cycles. Therefore UWB tags have low power requirements.
Disadvantages of UWB
- Requires cabling for data and time synchronization – For systems that measure the TDoA of UWB pulses to achieve high accuracy, precise timing between sensors need to be synchronized, requiring cabling.
- Expensive – UWB systems are more expensive than RFID systems, requiring a mesh of sensors to cover spaces and actively powered tags..
- Low emission limits – FCC has put low limits on UWB signal strength. For example, the limit is -51.dBm over 10.6GHz, meaning care is needed to make sure systems are certified for use in the country of deployment
GPS is so ubiquitous that it has become a proprietary eponym for Global Navigational Satellite Systems (GNNS).
The Global Positioning System, originally called Navstar GPS, is a U.S. government-owned satellite radio navigation system operated by the United States Space Force. Asset tracking with GPS tags is possible anywhere on Earth with an unobstructed line of sight to four or more GPS satellites.
GPS, or any other GNNS, works by triangulating its position based on a network of in-orbit satellites. These satellites are constantly communicating with each other to make sure their internal clocks are synchronized.
A GPS receiver on the ground picks up these signals and uses them to calculate its distance from each satellite. Once it has distance measurements from at least four satellites, the receiver can use trilateration to determine its exact location.
Advantages of GPS
- Global visibility of tracked assets.
- Stable and mature system.
- GPS based asset tracking systems can be scaled literally by adding GPS tags to assets.
- Practically interference-free.
Disadvantages of GPS
- Works only outdoors.
- GPS requires a line of sight with at least four satellites. As a result, GPS is unreliable in mountainous terrains or near tall buildings.
- High power consumption.
- Meter level accuracy – the typical accuracy of GPS is between three to ten meters.
Bluetooth Low Energy (BLE)
Bluetooth is a ubiquitous technology applied in many indoor positioning solutions. BLE has been around for over ten years, and its low power consumption gives it an advantage over other solutions like WiFi and GPS.
BLE systems utilize beacon and hub devices to establish their wireless networks.
BLE systems don’t typically require any scanning or searching. Most BLE system architectures utilize Received Signal Strength Indications (RSSI) to determine proximal asset locations as objects move. Additionally, BLE can calculate directional data using methods like Angle of Arrival (AoA) and Angle of Departure (AoD).
- Low power consumption.
- BLE tags can be inexpensive to buy.
- Accurate between one to three meters.
- Read range between thirty to eighty meters.
- Cross-functionality with common consumer devices; bring-your-own-device (BYOD) functionality.
- Latency can be an issue in some real-time applications.
- Signal interference and dropped data points.
- BLE solutions do not function well in highly-cluttered environments with lots of metal or reflective surfaces.
- Does not perform well in environments with moving parts causing interference.
The RFID (Radio-Frequency Identification) technology is several decades old. RFID has been used in many cases and continues to be valuable even as newer asset-tracking technologies have rolled out.
RFID technology has evolved over the years. The tags have become smaller and cheaper, and stable standards have emerged.
RFID solutions come in two different types: active RFID and passive RFID. Active RFID tags are powered by an internal battery, whereas passive RFID tags rely on the power transmitted from an external reader and can take the form of an inexpensive and easy to apply label.
RFID systems use electromagnetic readers and tags to function. RFID tags contain identification data that can be read by both stationary and hand-held RFID readers. Readers, also known as interrogators, can detect which tags are present.
Primarily, the reading process identifies the tags being scanned; however, this scan can also provide other data. For example, a doorway scanner can read an RFID tag as it crosses the door’s threshold, thus logging the time and the tag’s location.
The RFID technology operates in different frequency bands which makes it versatile.
Low-frequency RFID tags (125 kHz or 134 kHz) have a short read range of about 10cm and are more susceptible to interference.
High-frequency RFID tags (13.56MHz) have a read range between 10cm and 1m and are less impacted by interference.
UHF RFID tags (860MHz to 960MHz) offer the most extended read range of around 10m and are less impacted by interference than either low or high-frequency tags.
- Device longevity
- Small size
- Low-cost tags/labels
- Small radio signature
- Low precision
- Expensive readers
- Sometimes requires a manual scan
- Cannot provide real-time location data
- Wireless signals are easy to intercept
Wi-Fi based asset tracking systems use existing Wi-Fi networks to track the location of enabled devices. Although accuracy is lower than other methods (typically within 15m) and the tags are power-hungry, using existing Wi-Fi networks can make deployment inexpensive, and less obtrusive.
- Real-time location tracking
- Fewer data bridging systems are needed
- Can operate with existing WiFi networks
- The typical read range is between 60-100 meters
- Does not scale
- Accurate only to within 15 meters
- Tags are power hungry
- Security risks
Near Field Communication (NFC) enable two devices, one of which is usually a portable device, to communicate by bringing them within 4 cm (1.6 in) of each other.
NFC-enabled devices can read NFC tags, including smartphones, tablets, and laptops. NFC tags are often embedded in labels or stickers.
While both NFC and Bluetooth are short-range technologies, NFC differs from Bluetooth in several key ways:
Unlike Bluetooth, NFC doesn’t rely on manual configurations, and two NFC-compatible devices can connect automatically in less than a tenth of a second.
The maximum data transfer rate of NFC is 424 kbit/s, while the maximum data transfer rate of Bluetooth is 2.1 Mbit/s – five times faster than NFC.
- NFC tags can be read by NFC-enabled consumer devices like mobile phones, tablets, and laptops
- Fast set-up time
- Inexpensive tags
- Short working distance makes NFC suitable for high-density applications
- Compatible with existing passive RFID infrastructures
- Short read range
- Cannot be used to track asset location in a 2D or 3D space
Low-power WAN (LPWAN) is a wireless wide-area network technology designed for low-bandwidth, battery-powered devices. LPWAN offers long-range connectivity with low bit rates, making it ideal for the Industrial Internet of Things (IIoT).
Their power-efficient design allows LPWAN transceivers to run on small, inexpensive batteries for more than ten years.
LPWAN’s protocols are simple and light, reducing hardware design complexity and lowering device costs. Its long range and star topology reduce expensive infrastructure requirements, while license-free radio bands can further minimize network costs.
LPWAN supports more devices and a larger area than most other asset-tracking technologies. They can handle packet sizes from 10 bytes to 1 kilobyte at uplink speeds of up to 200 Kbps.
Low cost, lesser power requirement, and long range make LPWAN ideal for IIoT and machine-to-machine communication.
- Long-range wireless connectivity, from a few kilometers in urban settings to tens of kilometers in rural settings
- Can be used for large-scale deployments
- Tags have a long battery life
- Can be used for indoor and outdoor coverage
- Low data transfer rates
- Needs a network to deploy
Cellular asset tracking is a technology that uses the cellular network to track the location of assets. Cellular asset tracking systems use a combination of GPS and cellular networks to provide real-time location data for tracked assets. However, cellular tracking is often used without GPS.
Cellular asset tracking systems are often used for fleet management and to track large, high-value assets. These systems typically use 2G, 3G, or 4G cellular networks to provide location data.
Cellular tracking, while not very precise, is used to track larger assets where GPS-level accuracy isn’t necessary.
Cellular tracking is a reliable technology because it piggybacks on commercial cellular infrastructure. The commercial cellular industry’s standards, ubiquity, and uptime make cellular asset tracking appealing tracking technology.
- Long-range and global reach
- Cellular tags are power hungry
- It needs third-party cellular infrastructure to work
- Low accuracy
- Not reliable indoors and underground
The use of cellular technology is not new to the asset-tracking industry. 2G, 3G, and 4G technologies have been used for asset tracking for many years. However, 5G connectivity delivers some unique benefits.
5G offers increased reliability, decreased latency, and high bandwidth opening the door for various new opportunities where safety is paramount or the process is critical.
Low-latency and high bandwidth networks are well suited for applications such as controlling automated guided vehicles (AGVs) in a warehouse, real-time communication between robots in a smart factory, or streaming live video with artificial intelligence for quality control.
Future 5G releases are expected to improve the positioning accuracy of 5G systems, useful in industrial applications where organizations are considering deploying private 5G networks for communication and data transfer.
Dual Mode Devices
Dual-mode asset tracking uses two asset tracking technologies to track an asset. Dual-mode asset tracking is often used to track assets and processes that move between indoor and outdoor environments or to improve tracking accuracy.
Common dual-mode, or multi-mode tracking combines technologies including UWB, GPS, BLE, and RFID.
Which Asset Tracking Technology Should You Use?
The best asset-tracking technology depends on factors such as the type of assets being tracked, the accuracy required, the size of the deployment, the tracking environment, and the budget. The following points should be considered when selecting an asset-tracking technology:
- Accuracy of location data required (sub-meter, zonal, or presence)
- Location update rate (real-time to infrequent)
- Dimensions tracked (1D, 2D, or 3D)
- Number of tracked assets
- Criticality of the asset or process in which the asset is tracked
- Value of the asset
- Physical environment
- Ease of deployment
- Cost of the system
For a more comprehensive overview of selecting the best asset-tracking technology, refer to our guide on choosing the right asset-tracking technology.