Assets and people can be tracked in numerous ways. Two popular communication technologies for this purpose are Radio Frequency Identification (RFID) and Bluetooth Low Energy (BLE). Our Favendo technology is primarily based on BLE. However, we frequently receive customer inquiries asking about the advantages and disadvantages of BLE and RFID and which technology is best suited for specific use cases. So it’s time for a comparison.

What is RFID?

RFID uses radio waves to capture, read, and sometimes update digital data stored in RFID tags (also called Smart Labels). An RFID system includes tags, the antenna, and the reader. The antenna and reader work together to communicate with the tag. There are two types of RFID tags:

• Passive tags: These don’t have their own power source. They get powered by the signal from the reader.
• Active tags: These have their own internal battery.

The technology operates in various frequency bands: from low frequency (125 to 134 kHz), through high frequency (13.56 MHz) and ultra-high frequency (up to 960 MHz), to microwaves (2.45 GHz and above). The RFID Frequency determines the range and the accuracy of a solution.

What is BLE (RSSI / AoA)?

BLE is a technology that, like RFID, uses radio waves. It operates in the 2.4 GHz band and communicates over 80 channels. BLE-based tracking systems usually consist of:

• Transmitter (BLE tag/beacon): Attached to an asset or person. Comes in a variety of form factors and is typically powered with an internal battery.
• Receiver (tracker or relay): Installed in the environment to detect the signal from the BLE tag. Collect data from tags and relay it to a program that places it into a usable format.
• Middleware: Software that processes the data.
• User Interface (UI): Where users can view the tracking data, such as through an app or website.

There are two types of BLE systems: Received Signal Strength Indication (RSSI) and Angle of Arrival (AoA). RSSI is the measure of proximity of devices accomplished through the analysis and aggregation of signal strength in terms of decibels (dBm). AoA considers the angle from which a given BLE signal originates. This results in the biggest difference between RSSI and AoA-based systems, increased accuracy.

Let’s compare

Range

RFID: Passive tags usually have a limited range and must be read in close proximity to an RFID reader. Configuration of RFID devices often require the use of an additional device with NFC capabilities. Which is more time-consuming than BLE device configuration, and the user must be close enough (4-5cm) to the RFID tag to interact with it. Active RFID in the ultra-high frequency (UHF) on the other hand, can cover up to 100 meters.

BLE: Whereas BLE has a usual communication range of up to 100 meters. This allows BLE devices to be identified, read, or configured over much greater distances than RFID. Also, multiple BLE tags can be read or configured in groups, sometimes automatically, over greater distances. This saves both time and effort when setting up and configuring asset tracking systems.

Accuracy

RFID: For RFID, accuracy depends on the tags used, the reader, and the frequency band, ranging from several meters to a few centimeters. RFID systems can only provide position data for objects when they are within range of the reader. Furthermore, the accuracy of the data has a tendency to decrease as the distance between the tag and the reader increases. In most applications, RFID can only provide zone-level, i.e., is the asset in a specific room or not, positioning.

BLE: BLE systems, depending on whether it is an RSSI or an AoA system, can provide the location of a tagged object in a room from 3-5m (RSSI) down to 0.2m (AoA). Furthermore, BLE systems can and often do provide real-time location and positioning data. That allows users to track assets as they move through an organization’s facilities. The precision of location tracking heavily depends on the density and positioning of the trackers.

Connectivity and Scalability

RFID: RFID systems can be either unidirectional or bidirectional, depending on the type. Here too, it depends on the environment and signal strength, but typically no line of sight to the reader or constant connection is required.

BLE: BLE has the significant advantage of bidirectionality, allowing information to be both sent and received. Additionally, connections can be made to other BLE devices. With BLE RSSI, line of sight to the trackers is usually not required as long as the signal is not blocked, while BLE AoA generally requires line of sight for precise positioning.

Both systems are scalable. There are several considerations to take into account when up or down scaling a project, such as connectivity, the presence of power sources, etc. However, generally speaking, scaling a RSSI BLE system is very cost effective.

Compatibility

RFID: RFID systems require RFID and NFC equipment. This restricts the number of users to the amount of available hardware. Therefore, to increase the number of users, additional hardware has to be purchased and maintained.

BLE: BLE devices can communicate with nearly every Bluetooth-enabled device. The bidirectionality of BLE offers a wider range of functionality and use cases, making it the preferred choice in modern IoT ecosystems, such as in Industry 4.0, as it can be more easily integrated into existing networks and is expandable with little to no additional cost.

Costs

RFID: The costs of RFID can vary greatly depending on the implementation and specific requirements. Passive RFID tags are inexpensive compared to BLE devices and do not require batteries. However, in larger installations, the infrastructure costs for RFID readers can be high, especially if they need to be integrated into equipment like pillars or barriers.

BLE: The initial investment for BLE systems is probably higher than for RFID but can be significantly reduced by using existing BLE-enabled access points as trackers, thereby saving on hardware costs.

Energy Consumption

RFID: Passive RFID tags do not require their own power source and are powered by a nearby RFID scanner.

BLE: BLE tags use batteries that need to be replaced every two to eight years, depending on the transmission interval and configuration. Due to its own power source, BLE is the better option for applications where the tag needs to be constantly operational.

Security

RFID: RFID tags can be encrypted and equipped with access controls to prevent unauthorized access. However, security heavily depends on the protocols used.

BLE: BLE devices support modern encryption and authentication mechanisms and are protected by standardized security protocols. In addition, many smart devices, like tablets and smartphones, require a pin, a fingerprint, or facial recognition. A mobile application on that user’s device requires a valid set of credentials and could have two-step verification enabled. Hence, a BLE system has a multi-layered security posture.

Conclusion: The Agony of Choice

Both technologies have their advantages and disadvantages and are suitable for different application scenarios. RFID is ideal when simple solutions are required, particularly in applications without a continuous power source and over short distances. Passive RFID tags are very suitable for environments where only targeted queries are needed, and continuous monitoring is not necessary. BLE offers several key advantages in comparison, particularly regarding range, positioning accuracy, and bidirectional communication. BLE is particularly suitable for applications requiring precise location tracking and real-time updates. Additionally, it can be easily integrated into modern IoT infrastructures. Decision-makers are well-advised to first determine the system requirements and specific application scenario. There are a number of factors that should be considered when making a selection. Based on this, an informed decision can be made about which system offers the best cost-benefit ratio for their use case.