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Comparing RTLS Tags: RFID vs BLE vs UWB vs Wi-Fi
Real-time location systems (RTLS) are useful in industries as diverse as logistics and education. Organizations small and large have deployed them, and for multiple purposes. Manufacturers will use them to study the interaction between factory workers and heavy machinery as well as to record attendance or manage visitor access on the same day.
Depending on the use case(s) for each industry or even an organization within that industry, RTLS may be implemented using one of a handful of technologies whose end goal is to monitor location. So if you’ve heard the terms Ultra Wide Band or Bluetooth Low Energy and not known how they differ, let’s clear that up for you. What follows is a layman’s guide to four types of RTLS Tags.
Types of RTLS Tags
Bluetooth Low Energy or BLE
What it is: A technology that works on Bluetooth Low Energy to detect proximity of a BLE tag to readers. Benefits: BLE Tags are very easy to install, low-cost, offer moderate precision, and are extremely portable. Compatible with smartphones, too. Downsides: Distances aren’t always accurate as BLE measures proximity, not distance. However, this too can be resolved using techniques such as triangulation. Accuracy: Within 8 metres Range: Up to 75 metres Battery Life: 3 to 5 years Common use cases: Any indoor operations that do not require extreme precision (Check out Syook InSite for more)
Ultra Wide Band or UWB
What it is: Calculates distance by measuring the time it takes for radio waves to be transmitted between devices. Benefits: High accuracy, even with interference, and low latency (measurements can be made up to 100 times per second) Downsides: The infrastructure is expensive. While compatible with smartphones, it requires additional government certifications to be implemented. Accuracy: Within 30 cm Range: Up to 150 m Battery Life: Up to 2 weeks but rechargeable Common use cases: Any indoor operation that could benefit from extreme precision and needs to track only a small number of assets.
Passive Radio Frequency Identification or RFID
What it is: Passive RFID works through the transfer of radio frequency from a set of readers (affixed on objects such as a forklift) to a set of RFID tags (affixed on packages, for example). Benefits: Very precise and no need for a battery. As it works over short distances, interferences are easily managed. Downsides: Complicated to setup, works only over distances of 1 metre or under, thereby offering only a point in time location. Accuracy: Within 10 cm Range: Up to 1 m Battery Life: None needed Common use cases: Operations that require precise inventory management.
What it is: Wi-Fi signals are used to communicate with tags or any device connected to Wi-Fi. Benefits: Signal can be transmitted through a mobile device. Mobiles, tablets, laptops or any device on which Wi-Fi is enabled can be monitored. Easy to deploy it on mobile devices, although Wi-Fi tags are also available (at five to 10 times the cost of BLE tags). Downsides: Tags are expensive, which can make monitoring a large number of assets expensive. Tracking is imprecise. Accuracy: Within 15 metres Range: Up to 150 metres Battery Life: Up to three years Common use cases: A practical solution when it’s mostly people that need to be monitored, as in the case of a conference, for example.
As should be clear, there is no one-size-fits-all option in RTLS. While the common intention is to monitor location, the most suitable technology for each organisation depends on business requirements, the budget, flexibility required and much else. We hope that our distinction helps you arrive at what your organization needs. Should you have any questions about the technology and what will be suited to a specific location, contact the Syook team.