The Differences Between RFID and RTLS

By Simon Parker

While both help in identifying particular locations, there are various differences between the two technologies.

Have you ever wondered what the difference is between radio frequency identification (RFID) and real-time location system (RTLS) technologies? Let's find out.

In the manufacturing and health-care industries, the real-time location of machines, materials and manpower is becoming increasingly important and, thus, one hears the terms "RTLS" and "RFID" being used interchangeably. However, this is a misconception. While both RTLS and RFID help in identifying particular locations, there are various differences between the two technologies.

Explaining the Difference in Simple Terms
Let's start with RTLS. This technology is much more suitable for industries that are looking for overall global coverage. In order to pinpoint the exact location of any material within a facility, RTLS is the technology to use. This system works through a combination of Bluetooth technology and GPS in order to monitor and track objects and interactions when they occur.

RFID, on the other hand, uses portals or last-seen technology. It doesn't give you the global coverage that RTLS does, but it does tell you about the movements of products within a large area. This technology provides an approximate location but not the exact one.

Breaking Down the Definition of RTLS
RTLS is a form of technology which manages to track down the real-time location of a product or person by using a combination of Bluetooth and GPS technologies. In order for RTLS to work, a Bluetooth discoverable device must be registered to the system. Sensors are installed within the given environment, which work by picking up the exact location of the specific Bluetooth device.

There are two parts to real-time location systems. One is the Bluetooth indoor positioning system, which makes it possible to track individuals and objects from inside the premises. The second part is the GPS outdoor positioning system. When the system can no longer track objects inside the premises via Bluetooth, it will switch to GPS tracking in order to monitor the surrounding area.

The Two Types of RFID Technology
While RTLS has two parts to it, so does RFID technology. RFID enables you to transfer data wirelessly using an electromagnetic field. Signal is exchanged between two different devices to identify the location of a product or person. RFID technology is of two types: active and passive.

With active RFID, a signal is sent to a reader every few seconds and location is calculated using different methods, such as triangulation. With passive RFID, there are special reading devices and the technology works in approximation to them. In other words, it gives the reader a point-in-time location. At a department store, for example, a reader may send a signal to a tagged product, so an alarm will be set off if that product comes in close proximity to the designated point. The reader will not be able to give you the exact location, but will know where to look for it.

The various components of RTLS technology include Wi-Fi, ultrasound, Bluetooth, ultra-wideband (UWB), ZigBee, second-generation infrared and legacy infrared. Using triangulation software, some of these components offer an approximate location of a tagged commodity or person.

One problem with using RFID is that a user cannot determine if a product is situated to the left or right of a wall, since radio frequency signals cannot penetrate through floors, walls or ceilings. Infrared technology, in order to work flawlessly, needs a clear line of sight, as any hindrance in the field of sight can block signals, thereby leading to slightly distorted results. To obtain improved results, infrared can be combined with active RFID so that the technology can read through walls and other obstacles.

Ultrasound does not perform as well as the other options when it comes to a communication mechanism, due to its longer wavelengths that make it slower when compared to infrared. Wi-Fi is clearly the preferred technology used in the majority of locations, but its accuracy is limited to only 30 feet, which limits its popularity when it comes to tracking locations.

What Makes RTLS So Precise?
RTLS makes the best use of complementing software solutions by eliminating the weakness of individual software products, so that it can deliver clinical-grade precision to identify the location of a tagged object or person. RTLS delivers results that are safe, quick, reliable and exact, making it a valuable technology for so many industries that rely on locating their indispensable materials and manpower. Along with pinpointing an exact location, it also makes it possible for users to streamline processes, measure performance and predict the tools that will need to be incorporated.

Both of the technologies discussed above are great ways of assisting security professionals in determining the location of an object or person. While RTLS needs no intervention and manages to carry out automatic location readings to give precise locations of individuals or objects, RFID, on the other hand, detects if a tagged object has passed through a fixed designated stationary point. It does not necessarily report the current location that a business looks for, but will deliver last-seen results, thereby making it unsuitable to track down assets and personnel. Both RTLS and RFID technologies are great security solutions to aid in tracking the locations of people and items.

Simon Parker has more than 70 years of shared experience with Minerva Security, dealing with commercial business security and fire alarm systems.