If you're curious: at the supermarket checkout, cashiers don't need to scan items one by one—they can simply place a whole basket of goods on the counter to instantly complete the transaction. At the delivery station, parcels are sorted by scanning boxes with equipment next to the conveyor belt, automatically identifying their destinations. When swiping a work ID or passing through a residential access control, cards don’t need to be pressed tightly against the reader—just a quick flick suffices... Well, today I’ll tell you the answer: these amazing operations are all made possible by—RFID technology.
01. RFID is not an "upgraded version of QR codes."
Many people confuse RFID with QR codes and barcodes, but in fact, their differences are significant. Simply put, barcodes/QR codes need to be "visible and scannable", and the scanning device must be aligned with the pattern to recognize them; RFID technology relies on radio waves, and even if items are obscured by packaging or hidden in boxes, as long as they are within the signal range, they can be easily identified. More professionally speaking, RFID technology is essentially a set of "signal transmission and reception systems", mainly composed of three parts: tags, readers, and antennas. By combining these three, the function of "air separation recognition" can be achieved.
02. The operating logic and principle of RFID technology
In fact, the working principle of RFID is not complicated. It can be imagined as a "silent dialogue", which is divided into three steps, each with a clear division of labor:
(1) Reader "sends signal" - awakens dormant tags
The small squares on the express waybill, work ID chips, and small dots on the product packaging are mostly passive RFID tags. They are usually in a dormant state and do not actively emit signals. When the reader antenna emits radio waves of a specific frequency, tags entering that range will be activated and return information, with recognition distances ranging from a few centimeters to tens of meters, depending on the specific application.
(2) Tag "Reply to Information" - send out your "ID card"
Passive RFID tags have coils and chips inside. When receiving radio waves from the reader, the coil will convert them into electrical energy, instantly activating the chip. The chip immediately retrieves the stored "electronic ID card" information and sends it back through a miniature antenna.
(3) Reader "decoding information" - transmitting data to the system
After the reader antenna receives the tag signal, it will decode it into digital information and transmit it to the backend system (such as cash register and sorting system) through wired or wireless network. The system immediately completes operations such as pricing and sorting, and the entire process takes only about 0.1 seconds, which is much more efficient than scanning codes.
03. Core capabilities of RFID technology
The main reasons why RFID is gradually becoming popular among many enterprises are as follows:
(1) Second level group reading, doubling efficiency
Barcodes can only be scanned one at a time, while RFID readers can recognize multiple tags simultaneously. For example, when settling in a supermarket, each RFID tag in a whole basket of goods can be captured by the reader at the same time, without having to pick up and scan the code one by one. The checkout speed can be increased by 3-5 times
(2) Can be rewritten and reused
RFID tags are rewritable (such as turnover box tags used in logistics), which can clear old information and write new content after use. They can be reused thousands of times, making them more environmentally friendly and cost-effective than disposable barcodes.
(3) Suitable for various harsh environments
On rainy days, scanning the code may blur, and products wrapped in plastic bags may not be scanned, but RFID tags are not afraid of water, oil, or obstruction. For example, meat and seafood in cold chain transportation have labels attached to the inside of the packaging, which can still be recognized normally even after low-temperature freezing and water vapor soaking, making it convenient to track the transportation trajectory of the goods.
04. RFID technology has penetrated into every aspect of life
Nowadays, RFID technology is no longer just a "small tool" for scanning access control and checking out, but has penetrated into every aspect of our lives.
Retail industry: Real time inventory check, holding a reader and walking around the shelves to know which products are out of stock and which need to be replenished. The inventory work that originally took several days can now be completed in a few hours;
Logistics industry: From package dispatch to delivery, RFID readers at every stage record location information, allowing users to view logistics trajectories in real-time and avoid package loss or misdelivery;
Medical industry: RFID tags are attached to drugs and surgical instruments in hospitals, allowing nurses to quickly verify drug information through readers (to avoid sending the wrong medication), and to quickly count instruments before and after surgery;
Animal husbandry: Implanting RFI ear tags into livestock such as cattle and sheep can record their date of birth, vaccination status, health status, and achieve full traceability from pasture to table.
With the development of technology, RFID is constantly upgrading: for example, when combined with 5G and the Internet of Things, a single reader can simultaneously recognize tens of thousands of tags, and the coverage range can also be expanded to several hundred meters; For example, developing thinner and cheaper flexible labels that can be attached to clothing, food packaging, and even embedded in paper (future ID cards and passports may use RFID technology).
