Chain visibility: barcodes, RFID, NFC, BLE beacons

Over the years, various methods have been employed to understand the visibility of each package through its supply chain as it is transported from its storage location to its delivery destination. With the advent of digital systems, the “hand-written scripts” on packages evolved into “barcodes” that could be tracked at shipping and receiving points using barcode readers. Then came radio frequency identification (RFID) and near Field communication (NFC) technology, which eliminated the need for line-of-sight (required for barcodes) and provided a more efficient way to scan packages. RFID can also be used for contactless positioning of packages in warehouses or in transit. But why are beacons now replacing RFID? What RFID-based technology can’t achieve with beacons?

To find these answers, let’s review the evolution of supply chain visibility solutions and compare each technology, namely barcodes, RFID, BLE beacons, and their features and drawbacks. We’ll also see how NFC, a new technology emerging in the consumer space, performs in terms of supply chain or logistics visibility.

A barcode is a label affixed to a product or package that has an optically machine-readable representation of data that represents certain information about that package or product. Barcodes have evolved from one-dimensional to two-dimensional, and more recently to the popular QR code, which can store large amounts of data to identify specific objects. Barcode technology and its optical scanners enable supply chain managers for the first time to scan packages from any hub and link data to a central repository, such as ERP WMS or TMS.

Disadvantages of bar code:

Time and labor intensive: The first major disadvantage of barcodes is the time it takes to scan each package. If you ship 5,000 packages per day and it takes 3 seconds to scan each package at the warehouse, you’ll spend nearly 4 man-hours per day on “scanning.” If 50,000 packages were processed, it would take 40 man-days or nearly 14,600 man-days a year.

Inability to provide real-time location: The second major disadvantage of barcodes is that you can’t easily find a key package from a group of packages without re-scanning the entire pile. In addition, you cannot get the real-time location of the package through the barcode. For example, if your warehouse contains 5,000 packages, you need to scan one package at a time to audit your inventory. The same applies when your package is in transit.

Barcoding helps bring digital identity to packages, but it has proven labor-intensive due to “line-of-sight” requirements. In addition, they can’t locate the package in real time. This led to experiments with RFID technology.

RFID technology uses tags that contain tiny circuits that can be identified by radio waves. The label can be as thin as a paper label or as thin as a key chain, depending on the number of data strings it can store and the distance it can read. RFID tags are roughly divided into passive tags and active tags. Reading an RFID tag “does not require” a “line of sight” like a bar code, but the “reading distance” depends on whether the RFID tag is active or passive. RFID readers can be fixed or mobile readers, but your phone cannot be used to read RFID tags like bar codes.

A: Passive radio frequency identification

Passive RFID uses a tag (no battery) that captures energy from the radio waves emitted by the reader and reflects them back to the reader. Once the reflected wave is captured by the reader, the label and its parameters are identified. Because the radio wave is reflected like a boomerang, when the reader reads it, its intensity diminishes rapidly, making the reading range usually less than 20 feet.

Passive RFID tags are often used to track low-cost items at warehouse doorways and checkpoints where the required reading range is smaller.

Drawbacks of passive RFID in terms of supply chain visibility:

Unable to cover the warehouse: Since its reading range is very small, you need to walk on the floor and cover all corners with a mobile RFID reader. If you use fixed readers to cover the entire warehouse, you will need a large number of readers and incur high service and maintenance costs.

Complicated setup: Since your phone can’t double as an RFID reader, you need to set up expensive infrastructure on the truck to read the tags in transit. Reading range remains an issue in securing all packages in the container. Even in a warehouse, it’s a lot of work to install. You need a specific reader, network connection, router, etc.

Unable to provide real-time location: The reader does not naturally have GPS and GSM triangulation capabilities.

b. Active Radio frequency identification

Active RFID uses a tag with a built-in battery that sends its information to a reader like a cell phone, expanding the reading range to about 100 feet. Active RFID technology is used to monitor high-value packages or equipment in warehouses, freight yards and railways.

The high read range allows the reader to overcome the drawbacks of passive RFID solutions by using a limited number of readers to sense packages and devices throughout the yard or warehouse, but other drawbacks hinder its expansion. Let’s see what they are!

Disadvantages of active RFID in terms of supply chain visibility:

It is not scalable due to its proprietary nature: due to the proprietary protocol, the tag only communicates with its designated RFID reader. Your application requires specific readers and tags and cannot open source them.

In an emergency, a phone can’t double as a card reader: your trucks and warehouses need to have permanent readers, or drivers need to carry them with them and return them responsibly.

High cost: Economies of scale have not yet been achieved due to the limited number of labels manufactured (due to the proprietary nature of the protocol). This makes each active RFID tag cost a dollar or more, which may not be feasible for many use cases, such as last-mile deliveries that require one-time type tags.

Real-time location is not available due to power consumption: the reader requires a cellular connection and a GPS chipset to locate a package in transit in real time. This means that if you want to build real-time in-transit monitoring capabilities, the solution will become very power-hungry.

Setup complexity: Reader installation, network creation, and wiring mean that setup and maintenance can take a lot of man-hours.

As a result, RBI-based solutions, while addressing the “line-of-sight” scanning and reading range of barcodes, still fail to provide scalable, integrated visibility of packages moving within warehouses and in transit.

Let’s see how beacons can help address these shortcomings! We will also briefly compare BLE and RFID with Near Field Communication (NFC), a technology whose use in logistics or supply chain visibility applications has attracted a lot of attention in the consumer space

Beacons, Bluetooth tags, or BLE tags are similar to active RFID tags. They have a built-in battery that provides a long read range. The most unique difference between BLE and RFID is that the beacons use the energy-efficient Bluetooth Low Power (BLE) technology. BLE is a universally available protocol that also happens to be a feature that exists on most GSM chipsets (i.e., your phone), thus giving BLE Beacons a strategic advantage in terms of cost-effectiveness and scalability.

You can read the beacon using a mobile phone or any hotspot device that uses a GSM chipset with BLE. Since the GSM device is already connected to the network, you do not need to create a network, install a router, or a WiFi zone.

You can get real-time location by using GPS chips in GSM devices or through cellular triangulation, so you know not only if your package is in the truck, but also where the truck is.

High read range: Beacons have a higher read range than active RFID due to the energy-saving characteristics of BLE technology. You can cover several hot spots in a large warehouse with a single phone, or cover the entire length and width of a truck loading packages.

Lower power consumption: Beacons can efficiently transmit large amounts of information (sensor data such as temperature, humidity, light, etc.) without consuming too much power – this is also due to the nature of the BLE protocol. This allows BLE tags or beacons to last up to 3 years without needing to be recharged.

Cost effective: Thanks to the ubiquity of the Bluetooth protocol on mobile phones, tags are being mass-produced and are close to achieving economies of scale. Beacons already cost so little that you can throw them away after each use.

Near field communication, or NFC, is a relatively new technology. It is a close relative of RFID because it operates at the same bandwidth as high-frequency or HF RFID, i.e. 13.56 Mhz. NFC functions similar to active or passive RFID, where the tag can simply reflect the emitted radio waves, or use a small battery to actively emit radio waves to an NFC reader.

NFC card readers are common on today’s smartphones, most Android and Windows phones come with NFC card readers, but the biggest drawback of the technology is its extremely low reading distance (only within a few centimeters).

In fact, the technology was indeed developed to enable close-read applications, such as information sharing between smartphones, credit card authentication, and smartphone-based payments, where a user’s credit card or smartphone needs to be near an active or passive tag. Point of Sale (POS).

Is NFC effective in addressing supply chain visibility?

That’s not the case – if you’re hoping to get a large warehouse with lots of packages without spending too much time or man-hours. Nor can it be used to monitor packages shipped in containers or monitor last-mile deliveries.

Since reading packets or goods requires close proximity, it is almost identical to passive RFID, except that reading errors (or stray assets read in a zone) are sometimes minimized compared to passive RFID due to the needs of the asset. Get up close and personal with your readers.