A Brief Guide to Understand The Difference Between QR and RFID Tags
In today’s world of asset management, tags of all sorts are used to communicate with electronic data collection devices, and to identify and track items in many different ways. Some tags can store data and then allow that same data to be read back in a comprehensive manner. This communicates meaningful data to us and tells us something about that individual item, asset, or person. Depending on the type of tag, the method of communication or storage of data may differ and be more or less useful useful than others depending on user requirements.
In general, there are two types of asset or inventory ID tags, RFID and barcode. Barcode can be a linear, supermarket type or two dimensional (2D). The two main 2D code languages are QR and Data Matrix. Both serve the same purpose differing almost exclusively in language. For the purpose of this post we will explore only the use of tags in item level asset or inventory management. Tagging for stock keeping unit levels (e.g. cans of soup) is an entirely different tag need or technology and is served by a separate vertical industry software group.
What is RFID?
Radio Frequency Identification tags are read-only or read/write. Read-only tags allow only for a one-time unique ID to be written or stored on the tag. This allows for information to be sent to and/or retrieved from an external database where the tag ID is the unique attribute in the database and is transmitted at time of data transfer or query. The database can be cloud-hosted or in a local environment where the scanning device transmits and syncs when docked.
Read/write or writeable tags allows for data to be stored on the tag, and this information can be written and rewritten to the tag many times over. The amount of data that can be written to the tag depends on the size of the microchip in the tag. The fact that the tag can store data means that relevant data can be stored and retrieved without connecting to an external database. This has value when no cloud or local database is available while the tag is in the field and a user needs detailed data about the asset at that moment in time.
Both read and read/write tags can be passive or active. Passive is often used as a tool for supply chain management and optimization by allowing for real time asset and warehouse management over a short distance. Active tags are battery powered and are used where the read range to the tag is greater than what can be normally read with mid-range readers. Rail car management is a classic example where the distance from tag to reader is overcome by tags that emit a stronger radio frequency signal due to its on-board battery.
What is a 2D barcode? QR and Data Matrix
A quick-reference (QR) 2D barcode is different than a typical barcode in that it is two-dimensional. A typical barcode is linear in nature and can only hold a single alpha numeric string. Like a stock keeping unit ID or serial number on a car.
A 2D tag or label has a code that has height and width. Think of an airline ticket. Due to its technical make-up, a 2D tag can hold alphanumeric data in large volumes. It can also hold a unique signature that designates it as a web address, or contact info that can be imported into your smartphone.
In its simplicity a 2D tag can also be a simple data string acting only as a database ID for an asset like a license plate on a car. The explosive growth of 2D tags is primarily due to their ability to be read by the onboard cameras of smart phones. The use of 2D tags in asset management is skyrocketing in recent years with the growth in smartphone use in business virtually eliminating the need for dedicated devices in the work process of asset or equipment management.
Benefits of RFID
- They can hold a substantial reasonable amount of data and can display the data when read by a compatible device.
- Reading the The tag does not require a direct line of sight, and data can be transmitted when the tag passes a fixed reader.
Drawbacks of RFID:
- RFID systems are can be very expensive- they require special mobile or fixed computer readers to transmit or receive data
- The RFID tags chips can be sensitive to certain materials and liquids, which may limit where the tag can be placed on an item, as readability may be affected.
- In order to implement a RFID system, the entire local environment must be analyzed, including anything from the types of metals, lighting, and sources of radio interference, since the data is transmitted via radio frequency. A site survey is necessary to identify all sources of potential interference or weakening of the signal and can cause major disruptions.
Benefits of QR or DM tags:
- 2D codes can hold a significant amount of information, and can be printed in any in any size, on virtually any material, making them useful to manage many different types of assets or items.
- They can be scanned using most smartphones, allowing data can to be stored and received from almost anywhere.
- No additional devices required for data collection, since the device is already in your pocket.
- QR 2D tags are very inexpensive. Asset management using smartphones and printed tags can be set up for significantly less than a RFID system, providing users of any type a simple solution where a requirement for data collection exists.
Drawbacks of QR tags:
- QR codes lack the automation ability for proximity scanning like RFID- human input is necessary.
- A line of sight to the tag is necessary to scan the tag and input or extract data.
When should you use RFID?
RFID is the answer for your business where there is a requirement for proximity scanning. Often this is a necessity for supply chain management or where automation will have a significant impact on the time that is spent collecting data.
When Should You Use QR 2D or QR Tags?
2D tags should be used in all instances when proximity scanning is not required and when human interactive data collection is required a requirement in a business. This is very typical when paper-based forms are used in areas such as inspections or checklists. The use of QR tags can eliminate the need for paper-based data collection and can be a cost effective way to optimize your company’s current asset management system. QR tags allow data to be collected immediately into an electronic format, which is far more functional and useful than on a paper form.
QR and RFID tags both have their advantages and disadvantages over one another, and understanding the difference between QR and RFID tags will help determine which is the better solution for you. RFID is much more costly and is not the answer for all scenarios, while QR tags require manual entry but may improve efficiency of operational processes for your business if human input is still a necessary component of your business.