What is Near field communication (NFC) in Mobile ?

Near field communication (NFC) is the set of protocols that enables smartphones and other devices to establish radio communication with each other by touching the devices together or bringing them into proximity to a distance of typically 10 cm (3.9 in) or less.

Guess what ? Xiaomi has NFC tags manufactured. Which are basically stickers that you can program to do something when your phone reads the NFC . Read along to find more about NFC.

NFC tags contain data and are typically read-only, but may be rewriteable. They can be custom-encoded by their manufacturers or use the specifications provided by the NFC Forum, an industry association charged with promoting the technology and setting key standards. The tags can securely store personal data such as debit and credit card information, loyalty program data, PINs and networking contacts, among other information. The NFC Forum defines four types of tags that provide different communication speeds and capabilities in terms of configurability, memory, security, data retention and write endurance. Tags currently offer between 96 and 4,096 bytes of memory.

At its core, all NFC is doing is identifying us, and our bank account, to a computer. The technology is simple. It's a short-range, low power wireless link evolved from radio-frequency identification (RFID) tech that can transfer small amounts of data between two devices held a few centimeters from each other.

Unlike Bluetooth, no pairing code is needed, and because it's very low power, no battery in the device being read. By tapping your phone on a contactless payment terminal in a shop, train station or coffee shop is able to identify your account (and even your personal preferences, shopping habits and even your most frequently travelled route home) and takes payment through an app on your phone.

Android Pay

• As with proximity card technology, near-field communication uses magnetic induction between two loop antennas located within each other's near field, effectively forming an air-core transformer. It operates within the globally available and unlicensed radio frequency ISM band of 13.56 MHz. Most of the RF energy is concentrated in the allowed ±7 kHz bandwidth range, but the full spectral envelope may be as wide as 1.8 MHz when using ASK modulation.
• Theoretical working distance with compact standard antennas: up to 20 cm (practical working distance of about 4 cm.

There are two modes:

---

• Passive communication mode: The initiator device provides a carrier field and the target device answers by modulating the existing field. In this mode, the target device may draw its operating power from the initiator-provided electromagnetic field, thus making the target device a transponder.
• Active communication mode: Both initiator and target device communicate by alternately generating their own fields. A device deactivates its RF field while it is waiting for data. In this mode, both devices typically have power supplies.

Speed	Active device	Passive device
424 kbit/s	Man, 10% ASK	Man, 10% ASK
212 kbit/s	Man, 10% ASK	Man, 10% ASK
106 kbit/s	Modified Miller, 100% ASK	Man, 10% ASK

• NFC employs two different codings to transfer data. If an active device transfers data at 106 kbit/s, a modified Miller codingwith 100% modulation is used. In all other cases Manchester coding is used with a modulation ratio of 10%.
• NFC devices are able to receive and transmit data at the same time. Thus, they can check for potential collisions if the received signal frequency does not match with the transmitted signal's frequency.

• A standard Ultralight nfc tag can store a URL of around 41 characters, whereas the newer NTAG203 nfc tag can store a URL of around 132 characters.

Comparison

---

Aspect	NFC	Bluetooth	Bluetooth Low Energy
Tag requires power	No	Yes	Yes
Cost of Tag	$0.10 USD	$5.00 USD	$5.00 USD
RFID compatible	ISO 18000-3	active	active
Standardisation body	ISO/IEC	Bluetooth SIG	Bluetooth SIG
Network Standard	ISO 13157 etc.	IEEE 802.15.1	IEEE 802.15.1
Network Type	Point-to-point	WPAN	WPAN
Cryptography	not with RFID	available	available
Range	< 20 cm	~100 m (class 1)	~50 m
Frequency	13.56 MHz	2.4–2.5 GHz	2.4–2.5 GHz
Bit rate	424 kbit/s	2.1 Mbit/s	1 Mbit/s
Set-up time	< 0.1 s	< 6 s	< 0.006 s
Current consumption	< 15mA (read)	varies with class	< 15 mA (read and transmit)

Which Xiaomi Phones Support NFC ?

---

Xiaomi Mi3
Xiaomi 2A
Future on NFC !

---

Wearable Technology is growing.And so comes implants -

The xNTi NFC implant tag for Humans

https://dangerousthings.com/shop/xnt-ntag216-2x12mm-glass-tag/


NFC has also been embedded in jewellery and even temporary tattoos that unlocks your phone !.

Here is a Video of NFC on Xiaomi 2A

---

---

NFC Forum

---

http://nfc-forum.org/

Sources : WikiPedia ,techradar 2, DigitalTrends , Google Images , Youtube