What is NFC?

NFC (Near Field Communication) is short-range wireless communication technology. NFC can be viewed as WiFi, Bluetooth, 3G, 4G… but the difference is that it works on a different frequency and has a different principle of power and data exchange.

NFC can be divided into passive and active.

Passive

They are the size of a postage stamp and are only used to store and send data. They do not require an external power supply but generate the necessary energy for storing data by electromagnetic induction, which is generated by radio waves generated by an active NFC reader. As such, they can be used almost anywhere.

Passive NFC tags

Active

Active NFC must be part of a larger system and must have an external power supply. As passive NFC is used only to store and send data, active NFC is used to read and send data. So, if we store some information on passive NFC, with an active NFC reader we can read that information by simply going past the chip itself. Active NFC, as I said, must be integrated into a larger system, say a Smart device such as a mobile phone.

NFC technology in Smart devices

The application of NFC technology is increasing every year and more and more Smart devices are getting these chips. We can say that NFC in phones became the standard in 2012, when in the official advertisement for the Galaxy S3, Samsung also pointed out the possibility of sharing images from phone to phone by simply touching it.

Just lean one phone against the other, touch the image and it will be sent to another device in a second.

This is possible thanks to NFC technology. In this case, both phones have Active NFC that reads/sends information.

But, it is important to note that the file itself is sent via WiFi Direct technology, and only the connection is established using NFC. This is still the practice today because NFC cannot transmit a lot of data in a short time, but it can transmit a little data almost instantly (which is ideal for communication).

However, since the phone has an active NFC reader, it can also read passive NFC chips. So, you can bring the phone closer to the passive NFC chip and read the information from it.

One great example of NFC technology is paying at checkouts by simply swiping the card over the reader. In this case, the passive NFC chip is in the card and the active NFC reader is in a cash register.

The same logic has been applied to smartphones, so now we can pay with them instead of cards. In this case, we have two active NFC chips, with the passive one being copied from the card to the phone first so that it can be used later. You may have heard of this technology as Google Pay or Samsung Pay.

Another good example is cafes where there is passive NFC on every table with which you can order a certain drink. The information reaches the computer where employees see from which table and which drink was ordered.

Currently, many smart devices in the world have NFC. One of the criteria when buying my new phone was exactly that item - NFC.

NFC antenna

If you want to buy NFC tags, you can find them at very low prices on the Aliexpress website. I specifically bought 6 pieces for some 300 dinars > LINK.