RFID vs Bluetooth tags

RFID vs Bluetooth tags

When researching IoT networks, you’ll commonly come across tags that use either RFID or Bluetooth technology. Both can serve similar purposes, but they work in entirely different ways. Terminology is also important, so before examining the benefits of the technologies—it’s important to understand precisely the terms being used. For a brief explanation of some of the basic terminology and technologies involved in active and passive technology, please see Basics of RFID..

RFID is a technology that has been around for decades, and in wide use for the last 20 years. It benefits from extremely low-cost tags (a few cents) and can operate at a number of different radio frequencies. RFID works well for ‘snapshot’ data, or when the RFID tag is within close proximity to a stationary or mobile RFID reader. The reader infrastructure can be costly, especially when covering a large area, or many different areas. A large spectrum of different vendors (one vendor for tags, another for readers, and a third for data integration) for a complete solution can also increase complexity and cost.

Bluetooth Low Energy (also called BLE) is a much newer technology. Bluetooth benefits from much lower cost infrastructure, secured data communication, and the ubiquity of Bluetooth devices that surround us every day in the workplace and in the home. Bluetooth is also an ‘active’ technology—one that does not require scanning or placement near a reader to receive data. This standards-based Bluetooth ecosystem enables easy interoperability as well as low-cost devices for tags and receivers. Bluetooth also frequently incorporates data sensors, enabling the condition (temperature, humidity, fill level, etc.) to be communicated along with identification and location.

Benefits of RFID

As previously discussed, both RFID and Bluetooth Low Energy technologies can provide automation into many processes by reducing the manual labor of monitoring or inspecting. The use of radio technology allows more assets to be scanned faster and more accurately. This frees up teams to handle other tasks and focus on more productive efforts. It also saves money, as no need exists to have an employee dedicated to asset tracking.

Types of RFID: Active and Passive

Passive RFID (Radio Frequency Identification), hereafter called simply RFID, can operate at a number of different frequencies, but in principle behave in the same way. A reader provides energy to the tag, and the tag then uses that energy to transmit some data in return.

In Active RFID, the tag itself transmits a signal, generally at some assigned time interval, without having to be near a reader. As discussed previously in Basics of RFID, different types of Active RFID systems use different frequencies and sources of power to enable this transmission.

In the case of Bluetooth Low Energy (BLE), this is a very low power transmission—requiring minimal energy, so the infrastructure of reading devices tends to be simple and inexpensive.

Trade-offs in Selecting Passive or Active

Given the above distinction between Bluetooth Tags and Passive RFID tags given above, which can both be used for asset tracking, and which approach leads to the best results?

If absolute minimum tag cost is the sole criteria for system selection, then RFID is generally the best candidate, as RFID tags can be very inexpensive ((5 cents or lower for the simplest types of tags) or up to $1+ for complex passive RFID tags that are ruggedized, or that operate when attached to metal or other challenging surfaces. However, total system cost and performance are generally the most important criteria for system selection. With RFID systems, the expense and complexity of readers (which are essential for system functionality), as well as the complexity of data/system integration can frequently result in systems whose cost can exceed their benefits. Given the nature of the cost breakout between tags (inexpensive) and readers/infrastructure/integration cost (expensive) passive systems are best suited for automation/data collection in a small number of locations (readers).

In contrast, active systems will have more expensive tags—how much more expensive depends greatly upon the technology/type of active tags. However, the technology/complexity of receivers/readers is generally simpler and less expensive than that of passive systems. This means that active systems are much better suited for automation/data collection in a large number of locations—cases like supply chains, location (or temperature) across a large indoor or outdoor area, or retail locations.

In the specific case of Bluetooth Low Energy technology, low-cost tags are small and readily available as are a variety of low cost readers/receivers. This makes Bluetooth Low Energy an ideal choice for many use cases in the digital supply chain as well as retail and industrial verticals. The ubiquity of Bluetooth Low Energy devices all around us in the home and enterprise (phones, tablets, PCS, keyboards, earbuds, etc.) ensures a low cost infrastructure that may already be in place. Furthermore, the presence of Bluetooth Low Energy in almost every smartphone, provides for a broad range of ‘built-in’ existing readers.

Why choose Wiliot Pixels for your asset tracking set-up

Why choose between the benefits of passive RFID and Bluetooth tags for your tracking system?

Wiliot IoT Pixels can provide some of the best benefits of both types of systems, without compromising cost. Wiliot pixels are a low-cost, small-size, flexible tag the size of a postage stamp, that contains a computer and the technology to harvest energy from radio waves. The simplicity of the tags means they are far less costly than other Bluetooth beacons or Bluetooth Low Energy tags, because they offer the capability of being battery free Bluetooth communicators. Their ability to harvest energy means they can behave like an active BLE tag, emitting a data packet without having to be energized by an expensive reader, and because they are BLE based they can utilize the low cost BLE reader infrastructure. Furthermore, the Wiliot software system is cloud based, simplifying setup and integration.

Get the best of both worlds with Wiliot Pixels.