Near Field Communications (NFC) is an evolution of contactless data exchange which is being employed in mobile phone applications for data exchange and payment processing, among other applications. This presentation covers the evolution and technical details of this communications protocol along with compliance testing requirements. Learn more: http://wireless-connectivity-test.com

1. NFC Technology and Conformance
Testing

2. Agenda
l NFC Basics
l Standard Evolution
l Physical Layer Compliance Tests
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3. NFC Introduction
l Contactless data exchange
l Passive – active
l Active – active
l Close proximity ~ 10 cm
l Data transfer using the “near
field”
l Low carrier frequency of 13.56 MHz
l Magnetic coupling between
transmitter and receiver similar to
transformer principle
l Standard developed jointly by
NXP and Sony
l Backward compatible with
smart card technology
l ISO/IEC 14443 A/B
l JIS X 6319-4
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4. NFC Coupling Method
Information is coupled between the polling and listening
devices using the near field – equivalent to transformer
principle
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5. Frequency Spectrum of NFC Signal
l Auxiliary carriers transfer information from passive listener (target)
to poller (initiator) through load modulation on poller antenna
l Auxiliary carriers are not used in peer to peer communication
l Carrier is used as a power source in active-passive communications
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6. Modulation Types
l Poller (initiator) uses ASK
modulation on 13.56 MHz carrier
l Passive devices communicate
on auxiliary carrier via load
modulation
l ASK for 14443A and PSK for 14443B
l ASK directly on carrier for JIS X
6319-4
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7. Coding Types Used in NFC
l NRZ-L: logical 1 and 0 coded as high and low level and signal level
is maintained throughout a bit period
l Manchester: first half bit is high for a logical 1 and second half is
high for logical 0
l Modified Miller: negative going pulse after half a bit interval for a 1
and at the start of a bit interval for a 0. For a 1 followed by a zero,
no pulse
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8. Frequency and Time Representation
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9. Evolution of NFC Air Interface
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10. NFC Operating Modes
Each mode can
Use any of 3
technologies
l Card emulation mode (passive mode): behaves like existing
contactless card and conforms to one of the legacy standards
l Peer to Peer mode: both devices are active and exchange data
l Reader/Writer mode (active mode): the NFC device is active and
reads or writes a passive legacy RFID tag
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11. Poll Mode Resolution
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12. NFC Standards Overview
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13. NFC Tag Types
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14. NFC RF Measurements – Listening Device
l NFC Forum Reference Polling Device
l Sends commands to listening device
l Received response from listening device (load modulation)
l Command generator – modulated 13.56 MHz carrier
l Load modulation measuring tool – oscilloscope or signal anlyzer
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15. NFC RF Measurements – Polling Device
l NFC Forum reference listening device
l Receives polling signal from device under test
l Transmits appropriate response via load modulation
l Listening device response generator – arbitrary waveform generator
(AWG)
l Measuring waveform tool – analyzes the polling signal and
generates a trigger for the response generator
l Measuring Field tool – measures the carrier power from the poller
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16. NFC Reference Polling and Listening Devices
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17. RF Tests for NFC Devices in Polling Mode
l Carrier frequency accuracy
l Power level measurement
l Sufficient power to drive passive devices
l Measured within the specified volume above the coupling device
l Waveform characteristics
l Rise time, fall time, etc.
l Load modulation sensitivity
l Correct reception at minimum specified level
l Threshold level test
l Polling device must switch off its RF field when exposed to an RF field f
a certain strength
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18. RF Tests for NFC Devices in Listening Mode
l Load modulation measurement
l The signal strength of the load modulation must be within required limits
l Power reception
l The listening device must answer correctly even in bad conditions
l Frame delay time
l Response time from the end of the polling command to the start of
transmission from the phone in card emulation mode
l Important in NFC-A mode for anti-collision
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19. Test Setup for Polling Mode
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20. Test Setup for Listening Mode
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21. Carrier Power and Frequency Measurement
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22. Load Modulation
Load modulation
Polling command
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23. Automated Measurement Software
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24. Poller Timing Values
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25. Poller Signal vs. Time
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26. Listener Values
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27. Listener Signal vs. Time
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28. Summary
l NFC technology is an evolution of contactless data exchange
l Addition of peer to peer and read/write to passive smart card mode
l Backward compatible with legacy smart card
l The NFC forum has established both RF and protocol
compliance tests
l Guarantees interoperability
l RF testing verifies the air interface for polling and listening
devices
l Reference poller and listener
l Command and response generator (AWG and vector signal generator)
l Waveform analysis tool (oscilloscope with NFC trigger and I/Q
demodulation)
l Automation software controls acquisition and analyzes waveform data
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29. Contact Us
About Rohde & Schwarz
Rohde & Schwarz is an independent group of companies specializing in electronics. It is a leading supplier of solutions in
the fields of test and measurement, broadcasting, radiomonitoring and radiolocation, as well as secure communications.
Established more than 75 years ago, Rohde & Schwarz has a global presence and a dedicated service network in over 70
countries. Company headquarters are in Munich, Germany.
Europe, Africa, Middle East
+49 89 4129 12345
customersupport@rohde-schwarz.com
North America
1-888-TEST-RSA (1-888-837-8772)
customer.support@rsa.rohde-schwarz.com
Latin America
+1-410-910-7988
customersupport.la@rohde-schwarz.com
Asia/Pacific
+65 65 13 04 88
customersupport.asia@rohde-schwarz.com
www.rohde-schwarz-scopes.com
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