Near Field Communication (NFC) Flashcards
1
Q
What is NFC for?
A
- Secure
- Short-range
- Expanded upon radio-frequency identification (RFID) standards
2
Q
What are applications enabled through simple touch?
A
- One-touch setup of Wi-Fi and Bluetooth
- Electronic door locks
- Easy data exchange
- Mobile Wallet
3
Q
What are NFC operation modes?
A
- Peer-to-peer communication mode
- Reader/Writer mode
- Card emulation mode
4
Q
What is near field?
A
- Area from antenna to point where the electromagnetic field forms
- Field starts at the antenna as purely magnetic
- Uses inductive coupling
5
Q
What factor does magnetic field decreases by for near field?
A
1/(r^3) in free space where r is distance between tag and reader antenna
6
Q
What is far field?
A
- Area some distance from transmitting antenna at which electromagnetic wave has fully formed and separated from antenna
- Radiative coupling
7
Q
What factor does electromagnetic field decreases by?
A
1/r r = distance between tag and reader antenna
8
Q
How do reader and passive tag interact?
A
- Tag gets power from reader
- Two loop antennas of reader and tag form a transformer
- Tag has to be in near field to have sinusoidal current driven by reader
9
Q
How does passive tag get power?
A
Tag’s rectifier and power regulator convert AC to DC to power for tag
10
Q
How does Peer-to-peer communication work?
A
- Reader amplitude-modulates RF field to send info to Tag
- Tag’s demodulator converts AM signal to information bits
11
Q
PICC?
A
Proximity Integrated Circuit Card
12
Q
PCD?
A
Proximity Coupling Device (Reader)
