As RFID integrators, we are often met with the misconception that RFID and GPS are capable of providing the same results—when in reality they track items in very different ways and are best suited to different applications.
With so much confusion surrounding the differences between RFID and GPS, we aim to clear the air so you can make the best tracking decision for your facility and form reasonable expectations when planning for implementation.
What is GPS?
GPS stands for Global Positioning System and uses satellite signals to communicate location. Signal processors pick-up low-powered satellite signals and use an algorithm to calculate the exact location. The location is communicated back to earth using a cellular network or a long-range system.
What is RFID?
RFID stands for Radio Frequency IDentification—and is a form of identification technology that utilizes radio waves to transfer information. Information is stored in an integrated circuit (aka ‘chip’ or ‘tag’)—the tag transfers information to a reader, and a computer translates the information into a human readable form.
What Makes GPS and RFID Different?
While the definitions make it clear these two technologies are in fact different—what makes them functionally different?
The most obvious differentiating factor is that GPS is a technology created primarily to serve the purpose of tracking the position of items in near real time over long distances, while RFID is an identification technology that is capable of performing item tracking at key read points in a given workflow.
While both can effectively perform asset tracking, there are several differences in the way they do so and which applications they are typically used for—let’s talk about that:
How Location is Tracked
As we discussed previously, GPS calculates location after satellites pick up low powered signals from GPS devices. The location is then communicated through a cell network or long-range system. On the other hand, we haven’t discussed much about how RFID tracks location—and it isn’t as clear in the definition since RFID can be utilized far beyond location tracking.
The type of RFID used will play a major role in how you can use it for location tracking—regardless RFID requires specific scan points.
Both passive RFID and Active RFID can be traced through a process or chain of custody as they are scanned along the way. When tagged items reach scan points the reader will pick up their identification information and store it in a database. Through the database you can track the location of specific items based on their history—the most recent scan point should represent the current location of the item.
Active RFID is also capable of providing near real time location information—due to the requirement of scan points this is generally only applicable to situations where items are tracked within a single facility.
In these applications several readers are placed throughout a facility to serve as scan points. Active tags are programmed to transmit to nearby readers at predetermined intervals (usually every few seconds). Locations are determined by the last reader to detect the tag associated with an asset—when combined with appropriate software, items can be tracked as they move and are picked up by readers along the way.
You might be able to tell, now that we’ve discussed the differences in how these technologies track location, that they perform the task a bit differently. As we’ve pointed out these technologies can be used for similar applications—but you shouldn’t expect the same results.
In short—GPS is best suited for applications where items or shipments should be tracked in near real time over long distances while RFID is best suited for applications where items are tracked across different points in a process or workflow.
GPS is a global system and can be attached to items like phones or vehicles to create a near real-time tracking solution. In an ideal GPS application assets or shipments would be tracked in near real-time as they travel from one facility to another. The receiver may be attached directly to items, a vehicle or another device that would remain in close proximity to the items.
GPS can track items world-wide—allowing you to follow valuable items along their journeys around the world, even between different facilities you may not be directly involved with.
RFID, on the other hand is intended to track items between scan points within your processes and workflows.
RFID can be used to track your items as they enter and exit facilities, reach milestones along processing lines—or both! This process then builds an accurate history for each individual item—which not only ensures accurate tracking but also aids in quality control when you choose to include process and preparation details.
Just keep in mind, if you plan on tracking items through multiple facilities you will need to be working closely enough with them that they would be willing to install and use compatible equipment and software.
Active RFID is most commonly utilized for the tracking of valuable devices—it’s especially common in the medical field. Valuable medical equipment can be tracked in real time as it moves throughout a clinic or hospital.
Both GPS and RFID can provide accurate location tracking—but with very different results. If you want to track which touchpoints in your process, facility or chain of custody your items have reached, RFID might be a good fit. But, if you want to follow your items as they travel outside of your facility—even around the world, you may need to explore a more advanced GPS solution instead.
We hope we provided you with a better understanding of the differences between these technologies so you can seek out the most suitable technology for your application.