What Is RTLS

The acronym RTLS stands for real-time locating system. RTLS is often referred as RTLS systems, which incorrect, but convenient.

RTLS is nearly the same as indoor positioning system (IPS)

Although not limited to indoor positioning systems (IPS), when talking about RTLS, it is usually the various types of indoor positioning systems that are meant. Sometimes, they are also called local positioning systems (LPS).

But RTLS can easily be outdoor. Simply, when outdoor, usually, we have GPS. If we have GPS, then RTK GPS or other flavors of GPS is the most common solution for positioning and navigation.

Therefore, RTLS is almost always equal to IPS in practice.

GPS is GNSS. It is not RTLS

Although not limited to indoor positioning systems (IPS), when talking about RTLS, it is usually the various types of indoor positioning systems that are meant. Sometimes, they are also called local positioning systems (LPS).

Formally speaking, GPS is also an RTLS system, but GPS belongs to global navigation satellite systems (GNSS) along with GLONASS, Galileo, and BeiDou.

RFID is not a real RTLS

RFID stands for Radio Frequency Identification. Just as BLE, WiFi, LoRa, and ZigBee, which are not designed for positioning systems, can still be used for this localization and navigation, and RFID is not a positioning system, but, with a certain stretch, can still be used for this purposes.

Of course, the stretch is serious. You don’t know location of your mobile object or your mobile beacon or your tag. You know whether the tag was registered within 0.1-1m from an RFID reader. Typically, 0.05-0.1m and only for some special readers – within 1m. But you don’t even know the distance. You only know yer or no. Obviously, you don’t have XYZ coordinates of your mobile beacon. You have only XYZ of your RFID reader.

Many applications of RTLS

Since we focus on industrial applications, we do not touching in the article other areas, for example, retail, healthcare, hospitality, agriculture, security, etc. There are very many areas where RTLSs are used.

RTLS for palettes tracking? - not recommended

Typically, when talking about RTLS, one talks about mobile assets: forklifts, vehicles, people, robots, AGVs, drones. Much less about palettes.

Palettes are semi-mobile. Yes, they are moved, but they don’t move. Palettes are on the borderline between RTLS and RFID or some other identification methods, for example, QR/bar code identification with the help of mobile robots, drones, or people.

One of the major problem in warehousing – misplaced palettes. But employing RTLS for that is a bit an overshoot, because:

  • Mobile beacons are expensive, because they have battery, electronics, etc. Typically – tens of USD/EUR or more per mobile beacon (tag). To track forklift – fine. To increase safety of people – fine. But to put it on thousands of palettes – too expensive and still doesn’t solve many problems
  • RFIDs are better, but as discussed, they don’t give location. They simply report: “I am close to the reader”. One needs to know location of the reader in order to know location of the palette
  • RFIDs are far less expensive than mobile beacons for RTLS. But the reader must be mobile
  • Mobile reader can have various form: a person with RFID reader, robot/drone with a reader. It can be static RFID scanner embedded in gates. The RFID read out, when the palette or the object with the RFID passes through the gate
  • The same is valid for QR/bar code readers

Typical applications of RTLS

What real-time locating systems are good?

The answer on the question what real-time locating systems are good will depend on what you are looking for: accuracy, low latency, price, range, easiness to deploy, easiness to operate

What are RTLS tags?

RTLS tags or RTLS mobile beacons are wireless devices placed on the mobile objects in order to track their location inside the coverage area of RTLS (for example, building, warehouse, factory, hospital, etc.). You don’t track a person – you track his/her RTLS tag/mobile beacon. You don’t track a forklift – you track its RTLS tag.

Difference between RTLS tags and RFID tags

RFID tag can be considered as an RTLS tag, but as a very primitive and very rudimentary one. Typically, RTLS systems provide 2D (XY) or 3D (XYZ) coordinates of the RTLS tags. Whereas, the RFID tags provide gate-level coordinates only. An RFID system doesn’t give real-time coordinates of an RFID tag, until the tag is placed on the RFID reader or the RFID tag shall pass through a RFID portal. Therefore, calling RFID system a real-time locating system is a big stretch.

Review and comparison of different types of RTLS

Study more about different types of RTLS and RTLS technologies:

If anything is unclear, contact us via info@marvelmind.com