Have you ever wondered why ETC can automatically deduct fees without stopping? Why can a warehouse manager know what’s on the shelves just by waving a device? This is all thanks to a magical little thing – the RFID electronic tag. Today, we’ll use the simplest way to uncover its working principle!
1.What does an RFID tag look like?
An RFID tag looks like a small sticker (or like a laundry label in clothes), but it actually contains two key components inside:
①Microchip: used to store data (such as product numbers, production dates)
②Antenna: used to receive and transmit signals
2.How does it work?
Step 1: The reader “calls out”
Imagine that the RFID reader is a “loudspeaker” that continuously emits radio waves (similar to Wi-Fi signals). When a tag enters this signal range, it will be “awakened”.
Active tags: They come with their own batteries and actively send signals like mobile phones (the signals can travel a long distance, up to 100 meters).
Passive tags: They have no battery and are powered by the radio waves of the reader (similar to a solar calculator).
Step 2: Label “Reply”
The activated tag will use an antenna to “send back” the data in the chip. For example:
If it is a product label, reply: “I’m product A, produced in 2023”
If it is an ETC tag, reply: “I am the license plate A12345”
Step 3: The reader “understands” and takes action
After the reader receives the reply:
Supermarket: Add the item to the shopping list
ETC: Deduct fees from the bound bank card
Warehouse: Update inventory quantity
3.Why is RFID more powerful than barcodes?
| Comparison between Barcode and RFID Tag | ||
| Comparison items | Barcode | Etichetta RFID |
| Reading method | Must be scanned by aligning | Read up to 15 meters |
| Reading speed | One at a time | Hundreds at a time |
| Environmental requirements | It cannot be dirty or wrinkled. | Waterproof and dustproof |
| Data capacity | Only serial numbers can be stored | Can store more information |
| Price | Almost free | A few cents to dozens of USD |
4.Applications of RFID in Daily Life
①.ETC Charging: The fee will be automatically deducted when the vehicle passes.
②.Supermarket Anti-theft: An un-demagnetized label will trigger an alarm.
③.Pet microchip: Scan it when the pet gets lost and you’ll know who the owner is.
④.Express Logistics: Second-level inventory of full containers of goods.
5.In summary
1.RFID tags are smaller than grains of rice and can be implanted into trees to prevent deforestation.
2.In the future, supermarkets can use RFID to achieve “grab-and-go” automatic checkout.
3.The RFID electronic tag is like a “small speaker” installed on an item, enabling them to “talk” from a distance. Although it is a bit more expensive than a barcode, its convenience is changing our lives. The next time you see an ETC or a supermarket anti-theft door, you’ll know what kind of cutting-edge technology is hidden inside!