These days we see barcodes everywhere. Almost every product has a unique barcode, which contains all the information about the product. 1D barcodes can only hold a maximum of 85 characters and 2d Barcodes can store over 7,000 characters. With 2D barcodes even complex information like expiration dates and serial numbers can be seen easily.
Before we get into RFID, let’s see how does a barcode and a barcode scanners work?
If you look at a barcode, you can’t just make a wild guess on where one number ends and another one begins. Each digit in the product number is given the same amount of horizontal space: exactly 7 units. Then, to represent any of the numbers from zero to nine, we simply color those seven units with a different pattern of black and white stripes. So, in order to denote each number, there is a certain combination of white and black for each number from 0-9. The combination for each number is shown in the image below.
So, how the scanner knows to read these? When light reflects back off barcode into a light-detecting electronic component called a photoelectric cell. White areas of the barcode reflect most light; black areas reflect least. The cell generates a pattern of on-off pulses that correspond to the black and white stripes.
RFID(Radio frequency identification):
In barcodes, scanner could only scan one barcode at a time, but in RFID, a bunch of tags can be scanned at a time even from longer distances (up to 100 meters in some cases). RFID tags can be used in many places hotels, aeroplains, railways etc… With this technology in operation, you can just walk out of the grocery store with your products through the RFID scanner and without even waiting in a long billing line, get your total bill and payment done.
How RFID works?
A RFID has a tag or label and a reader. Tags are embedded with a transmitter and a receiver. The RFID component on the tags consists of a microchip that stores and processes information, and an antenna to receive and transmit a signal. The tag contains the specific serial number for one specific object.
To read the information encoded on a tag, a two-way radio transmitter-receiver called an interrogator or reader, emits a signal to the tag using an antenna. The tag responds with the information written in its memory bank. The interrogator will then transmit the information.
A passive RFID tag will use the interrogator’s radio wave energy to relay its stored information back to the interrogator.
A batter powered RFID tag is embedded with a small battery that powers the relay of information.
So, definetely it might be the future of barcodes…
Fun fact- If a smartphone is inside an aluminum foil, covered with aluminum foil, it can’t be detected by any RFID scanner even your phone can’t recieve any calls.