WAS_Week12_RFID_1 - Communication Technology Laboratory

parsimoniousknotΔίκτυα και Επικοινωνίες

16 Φεβ 2014 (πριν από 3 χρόνια και 5 μήνες)

69 εμφανίσεις

RFID I


System and Features

2

Communication Technology Laboratory

Wireless Communication Group

Schedule



8:15
-
9:00

9:15
-
10:00

10:15
-
11:00

11:10
-
11:55

Week 1



Fundamentals of wireless
communications. 1


Fundamentals of wireless
communications. 1

Fundamentals of wireless
communications. 1

Week 2

Introduction to

Exercises

Fundamentals of wireless
communications. 2

Fundamentals of wireless
communications. 2

Fundamentals of wireless
communications. 2

Week 3



Fundamentals of wireless
communications. 3

Fundamentals of wireless
communications. 3

Fundamentals of wireless
communications. 3

Week 4

Presentation of Ex 1/ 1

Presentation of Ex 1/2

WLAN
-

1

WLAN
-

1

Week 5

WLAN
-

2

WLAN
-

2

Week 6

Introduction
-


Second Exercise

Presentation of Ex 1
-


Combination Task

WiMAX

1

WiMAX

1

Week 7

Vehicular Networks

Vehicular Networks

Week 8

Presentation of Ex 2/1

Presentation of Ex 2/2

UWB 1

UWB 1

Week 9

Introduction
-


Third Exercise


Presentation of Ex 2


Combination Task

UWB 2

UWB 2

Week 10

Wrap up of Ex 2

WBAN

WBAN

Week 11


Presentation of Ex 3/1

Presentation of Ex 3/2

WPAN

WPAN

Week 12



Presentation of Ex 3



Combination Task

RFID 1

RFID 1

Week 13





RFID 2

RFID 2

3

Communication Technology Laboratory

Wireless Communication Group

Outline


Introduction


RFID Main Components


Fundamental Operating Principles


Multiple Access

4

Communication Technology Laboratory

Wireless Communication Group

Introduction


Radio Frequency Identification (RFID):

automatic identification method for storing and/or retrieving data
to/from an electronic device through radio frequency or magnetic
field variations


5

Communication Technology Laboratory

Wireless Communication Group

Introduction


Technology

6

Communication Technology Laboratory

Wireless Communication Group

Introduction


Strengths and Weaknesses


Strengths of RFID technology



Line
-
of
-
sight not required


Multiple tags identification


Long range identification feasible


Can read/write to tags


Operates in harsh environments


Memory to store data


Possibility to integrate sensors


Drawbacks


Costs


Unreliable under certain conditions


7

Communication Technology Laboratory

Wireless Communication Group

Introduction


Applications


Automatic Identification

Tracking and

Location Monitoring

Security and

Access Control

Ski ticketing

Car anti
-
theft



Smart shelf

Pallet tracking

Livestock identification




8

Communication Technology Laboratory

Wireless Communication Group

Introduction


New field to investigate...ubiquitous world ?!

9

Communication Technology Laboratory

Wireless Communication Group

Introduction


Is RFID the right technology ?

Hitachi produces the world's smallest RFID chip: mu
-
Chip

0.4 mm x 0.4 mm

Powder RFID chips next to a human hair

0.05 mm x 0.05 mm

Pictures taken from:
http://nexusilluminati.blogspot.com/2011/05/rfid
-
powder
-
worlds
-
smallest
-
rfid
-
tag.html

(under
Creative Commons Copyright)

10

Communication Technology Laboratory

Wireless Communication Group

Introduction


The Internet of Things (IoT)


the term IoT have been coined by a member of the
RFID

development community circa 2000


referred to the possibility of discovering information about a tagged
object by browsing an Internet address or database entry that
corresponds to a particular
RFID
.


IoT have seized on the phrase to refer to the general idea of things,
especially everyday objects, that are readable, recognizable,
locatable, addressable, and/or controllable via the Internet

whether via
RFID
, wireless LAN, wide
-
area network, or other
means.

Source:
http://www.dni.gov/nic/PDF_GIF_confreports/disruptivetech/appendix_F.pdf

11

Communication Technology Laboratory

Wireless Communication Group

Introduction


Technology roadmap
:
IoT

RFID tags for facilitating
routing, inventorying,
and loss prevention

Demand for expedited

logistics

Surveillance, security,
healthcare, transport, food
safety, document management

Cost reduction leading to
diffusion into 2
nd

wave of
applications

Locating people and

everyday objects

Ability of devices located
indoors to receive geolocation
signals

Teleoperation and
telepresence: Ability to
monitor and control distant
objects

Miniaturization, power
-
efficient
electronics, and available
spectrum

Software agents and

advanced sensor

fusion

Physical
-
World

Web

Ubiquitous Positioning

Vertical
-
Market Applications

Supply
-
Chain Helpers

2000

2010

2020

time

Technology
reach

Reproduced based on
http://www.dni.gov/nic/PDF_GIF_confreports/disruptivetech/appendix_F.pdf

(Source: SRI Consulting Business Intelligence)

12

Communication Technology Laboratory

Wireless Communication Group

Introduction


IoT

enabling

building blocks


Machine
-
to
-
machine interfaces and protocols of electronic
communication


Microcontrollers


Wireless
communication


RFID
technology


Energy
harvesting technologies


Sensors


Actuators


Location
technology


Software

Source:
http://www.dni.gov/nic/PDF_GIF_confreports/disruptivetech/appendix_F.pdf

13

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

main components


For the most part, RFID systems comprise three
principal components:


Reader(s)


Transponder or tag(s)


Host/Application/Middleware


14

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

main components

15

Communication Technology Laboratory

Wireless Communication Group

RFID Systems


Frequency Bands

LF

MF

HF

VHF

UHF

100K

1M

10M

100M

1G

10G

Frequency (Hz)

inductive

radiative

16

Communication Technology Laboratory

Wireless Communication Group

RFID Systems


Frequency Bands




Frequency

125/134 KHz

13.56 MHz

860
-
960 MHz

2.45 GHz


Access Control


Animal Tracking

• Often used for vehicle
identification.



Can be used globally
without a license.
Sometimes referred to
as LowFID.


Smart Cards


Smart shelve tags for
item level tracking


Library Books


Airline Baggage


Maintenance data
logging


Electronic ticketing



Contactless payment


Access control



Garment tracking


Pallet tracking


Carton Tracking


Electronic toll collection


Parking lot access


EPC standard built around
this frequency.


This band cannot be accessed
globally and there are
significant restrictions on its
use. When it is used, it is
often used for asset
management, container
tracking, baggage tracking,
etc.

• Airline Baggage

• Electronic toll collection

• Used for long range
tracking and with active
tags

Typical Applications


17

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Reader


Reader


Different frequency ranges


Conform to different standards and protocols


Different types: proximity (<10cm), mid range (<1m) or large range
(>1m) readers


Readers can be at fixed points (entrance/exit, point of sale,…) or can
also be mobile (portable)


Different shapes and sizes


Main functions:


Activate the tag and (passive tags) supply energy


Structure the communication sequence with the tag


Transfer data between the application software and a contactless
data carrier


Perform anti
-
collision procedure


Authentication procedure



Price: 50…2000$

18

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Reader


Block diagram

19

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Reader


HF interface: inductive system

20

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Reader


HF interface: microwave system

21

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Reader


Examples

22

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Tag


Tag


Different operating frequencies


Different sizes and forms


It can be attached to almost everything


pallets, vehicles, shirts, pets, luggage, electronic devices,…


Different capabilities


Different types:









Price: 0.05…200$

23

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Tag


Block diagram

HF interface: inductive tag

24

Communication Technology Laboratory

Wireless Communication Group


Power Supply


A very important feature of RFID systems is the power supply to the
transponder


Tags need energy for two reasons


To power the internal microchip


To transmit data to the reader


Categories of tags


Passive tags


No internal battery


The energy transmitted by the reader (electrical/magnetic field) is used
for both tasks


Semi
-
active tags


Internal battery used for power the microchip


The energy from the reader is used for data transmission


Active tags


Internal battery is used for both tasks


RFID Systems
-

Tag

25

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Tag


Standards (Air interface Protocols)



Tag
Type:

Frequency

125/134 KHz

5
-
7 MHz

13.56 MHz

303/433 MHz

860
-
960 MHz

2.45 GHz

Passive

ISO 11784/5,

14223

ISO18000
-
2

HiTag

ISO10536

iPico DF/iPX

MIFARE

ISO14443

Tag
-
IT

ISO15693

ISO18000
-
3

TIRIS

icode

ISO18000
-
6A,B,C

EPC class 0

EPC class 1

Intellitag

Title 21

AAR S918

Ucode

ISO18000
-
4

Intellitag

μ
-
chip

Semi

Passive

AAR S918

Title 21

EZPass

Intelleflex

Maxim

ISO18000
-
4

Alien BAP

Active

ANSI 371.2

ISO18000
-
7

RFCode

ISO18000
-
4

ANSI 371.1

26

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Tag


Freq.

Standards

Title

Year

LF

ISO 11784/5

RFID of Animals
-

Technical Concepts

1996

LF

ISO 14233

RFID of Animals


Advanced Transponders

2003

LF

ISO 18 000 Part 2 Type A/B

Parameters for Air Interface Communications below 135 kHz

2004

HF

ISO 15 693

Identification Cards


Vicinity Cards

2001

HF

ISO 14443Type A/B

Identification Cards


Proximity Cards

2001

HF

ISO 18 000 Part 3 Mode 1/2

Parameters for Air Interface Communications at 13.56 MHz

2004

HF

EPCglobal Class 1 13.56 MHz ISM Band Class 1

Radio Frequency Identification Tag Interface Specification

2003

UHF

ISO 18 000 Part 6 Mode A/B

Parameters for Air Interface Communications at 860 to 930 MHz

2004

UHF

EPCglobal Class 0 (Gen. 1) 860 MHz
-
935 MHz
Class 0

Radio Frequency Identification Tag Protocol Specification

2003

UHF

EPCglobal Class 1 (Gen. 1) 860 MHz
-
960 MHz
Class 1

Radio Frequency Identification Tag Radio Frequency & Logical
Communication Interface Specification

2002

UHF

EPCglobal Class 1 (Gen. 2)

UHF Class 1 Generation 2 Protocol

2004

MW

ISO 18 000 Part 4

Parameters for Air Interface Communications at 2.45 GHz

2004

27

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Tag


Example: ISO 15693 State diagram

28

Communication Technology Laboratory

Wireless Communication Group


Information storage and processing


RFID Systems
-

Tag

29

Communication Technology Laboratory

Wireless Communication Group


Data access


Read only tags


Write once and read many times


Communication with the reader is unidirectional, with the tag
continuously sending its ID to the reader


Data transmission from the reader to the tag is not possible


Cheap, low power and fast read


Read
-
write tags


ID plus additional read
-
write memory


Advanced memory structure and security features


Crypto functions

RFID Systems
-

Tag

30

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Tag


Examples

31

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Host/Application/Middleware


Host/Application/Middleware


In applications like e.g. supply chain management and logistics,
there is no longer a one
-
to
-
one relationship between the reader
and the application


These applications need a middleware that manages large
deployments of readers and the amount of data these readers
capture


Middleware price: 5K…50K$


32

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

Host/Application/Middleware


Middleware functionalities


33

Communication Technology Laboratory

Wireless Communication Group


Air Interface: coupling


The way the reader and the tag send/receive information or power


Coupling in the
near field

or the
far field


The (magnetic) near field is an energy storage field


It drops off ~ 1/r
3


The electromagnetic far field is an energy propagating field


It drops off ~ 1/r





Ex. at 13.56MHz

Fundamental Operating Principles

34

Communication Technology Laboratory

Wireless Communication Group


Inductive coupling

Fundamental Operating Principles

35

Communication Technology Laboratory

Wireless Communication Group


Backscatter coupling

Fundamental Operating Principles

36

Communication Technology Laboratory

Wireless Communication Group


Communication mode



F
DX:

E
n
er
gy

t
ra
n
s
f
er

Dow
nlin
k

Up
lin
k

E
n
er
gy

t
ra
n
s
f
er

Dow
nlin
k

Up
lin
k

E
n
er
gy

t
ra
n
s
f
er

Dow
nlin
k

Up
lin
k

HDX:

SEQ:

Full duplex (
FDX
)

Half duplex (
HDX
)

Sequential (
SEQ
)

Fundamental Operating Principles

37

Communication Technology Laboratory

Wireless Communication Group


Coding in the baseband




Fundamental Operating Principles

38

Communication Technology Laboratory

Wireless Communication Group


Modulation schemes


Amplitude
-
shift keying (ASK)


Changing the amplitude between two levels


Modulation index: 10%…100%



Frequency
-
shift keying (FSK)


Switching between (two) frequencies


Often 2
-
FSK




Phase
-
shift keying (PSK)


Switching the phase (e.g. 0 and 180 degrees)


Fundamental Operating Principles

39

Communication Technology Laboratory

Wireless Communication Group


Load modulation


The baseband signal is first modulated (ASK,FSK or PSK) using a
subcarrier


The modulated signal is used to switch the load resistor on and off


The actual information is carried in the sidebands of the two
subcarrier sidebands


Fundamental Operating Principles

40

Communication Technology Laboratory

Wireless Communication Group


Anti
-
collision algorithms


Tag collisions


Tag collisions mean that more than one tag responds to a reader at
the same time. In many cases this makes tag recognition
impossible.


Since low
-
cost passive tags cannot figure out neighboring tags or
detect collisions, tag anti
-
collision algorithms are very important in
RFID systems



Reader collisions


Reader collisions occur where neighboring readers interrogate a tag
simultaneously and confuse it


Can be

easily


solved because readers can detect collisions and
communicate with the others


Multiple Access

41

Communication Technology Laboratory

Wireless Communication Group


Tag anti
-
collision algorithms


Broadcast mode


Reader broadcasts energy and



the tags receive the transmitted data



Multiple
-
access to a reader


All transponders may react simultaneously


Goal
: minimize the required time for



identifying all tags



Multiple
-
access and anti
-
collision procedures



Multiple Access

42

Communication Technology Laboratory

Wireless Communication Group


Time division multiple access (TDMA)


Deterministic protocols


High reader to tag communication


Typically tree
-
walking algorithm


Stochastic protocols


Less reader to tag communication


Typically ALOHA
-
based algorithm (e.g. slotted ALOHA)





Collision

Tag 1

Tag 2

Reader

Tag 3

Multiple Access

43

Communication Technology Laboratory

Wireless Communication Group


Binary Tree (EPCglobal Class 0)



Multiple Access

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0001

0100

0101

1000

1100

1101

1111

The reader starts a tree traversal
by sending the special symbol
NULL followed by a binary 0

Reader: NULL, 0

Tag Reply:

0001

0

0100

0

0101

0

1000

1

1100

1

1101

1

1111

1

0

1

NULL

Reader
symbol

44

Communication Technology Laboratory

Wireless Communication Group


Binary Tree (EPCglobal Class 0)



Multiple Access

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0001

0100

0101

1000

1100

1101

1111

The reader hears both 0 and 1,
and chooses to reply with a 0

Reader: 0

Tag Reply:

0001

0

0100

1

0101

1

1000

(mute)

1100

(mute)

1101

(mute)

1111

(mute)

0

1

NULL

Reader
symbol

45

Communication Technology Laboratory

Wireless Communication Group


Binary Tree (EPCglobal Class 0)



Multiple Access

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0001

0100

0101

1000

1100

1101

1111

The reader hears both 0 and 1,
and chooses to reply with a 0

Reader: 0

Tag Reply:

0001

0

0100

(mute)

0101

(mute)

1000

(mute)

1100

(mute)

1101

(mute)

1111

(mute)

0

1

NULL

Reader
symbol

46

Communication Technology Laboratory

Wireless Communication Group


Binary Tree (EPCglobal Class 0)



Multiple Access

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0001

0100

0101

1000

1100

1101

1111

The reader hears only 0 and so
echoes that bit

Reader: 0

Tag Reply:

0001

1

0100

(mute)

0101

(mute)

1000

(mute)

1100

(mute)

1101

(mute)

1111

(mute)

0

1

NULL

Reader
symbol

47

Communication Technology Laboratory

Wireless Communication Group


Binary Tree (EPCglobal Class 0)



Multiple Access

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0001

0100

0101

1000

1100

1101

1111

The reader hears only 1 and so
echoes that bit; the (simplified)
EPC for one tag has been received

Reader: 1

0

1

NULL

Reader
symbol

48

Communication Technology Laboratory

Wireless Communication Group


Slotted Aloha variant


Q Protocol (EPCglobal Class 1
Generation 2)


The reader specifies the number of slots in the inventory round


Each tag randomly chooses a location to reply within the round


The reader issues short commands to mark the beginning of each
slot within the round


If a tag has chosen that slot, it replies with a random number


If the reader can decipher the number and acknowledge it, the tag
sends its EPC (Electronic Product Code)





Multiple Access

Inventory

Query (Q)

arbitrate

arbitrate

arbitrate

arbitrate

arbitrate

3

7

4

0

7

winner

reply

each tag


rolls die


2
Q

Reader

49

Communication Technology Laboratory

Wireless Communication Group


Capture effect


If one tag is closer to the reader antenna than the others that tag
may be able to override the data packets from the other tags as
result of the greater signal strength at the reader


When does a weak signal not disturb a strong signal ?


The problem of

weak collisions

...





Multiple Access

50

Communication Technology Laboratory

Wireless Communication Group

RFID Systems
-

system design


Why study operating principles ?


Selecting the RFID system that is the most appropriate for your
application or business


How to select an appropriate RFID system ?


For each application there is an appropriate RFID system in
terms of


Operating principles: frequency, range,…


Functionality: read
-
only, read/write,…


Physical form: static readers, handheld readers,…


Costs



One size fits all


慰灲潡a栠摯敳潴⁷潲欠景爠慬f 剆䥄⁡灰汩捡瑩t湳n!!!


RFID system design is driven by different factors

51

Communication Technology Laboratory

Wireless Communication Group









Read range




Data rates


Robustness to noise

Speed for reading multiple tags




Costs

Power Supply

Coding

Data Access

Information Storage

Anti
-
collision algorithms

Tag Antenna Design

Environment

Chip Design

Reader Design

Standards

Reader Antenna Design

Coupling

Frequency

Modulation

RFID Systems
-

system design