RFID TechnologyRFID TechnologyAn IntroductionAn Introduction

OutlineOutline • What is RFID

• RFID timeline

• The RFID system

• Technical issues

• Benefits and tradeoffs

• Some Applications

What is RFID?What is RFID?

• Radio Frequency Identification– Use of radio frequency (air interface) for automatic identification

in proximity

• An identification technology– Bar coding– Magnetic stripe

• Old technology– new innovations– new applications

A UHF ReaderA UHF Reader

902-928 MHz902-928 MHz

TagsTags

TimelineTimeline

• 1940s – Radar refined and used, RFID invented in 1948

• 1950s – Early exploration of RFID

• 1960s – Development of the theory of RFID, field trials

• 1970s – Explosion of RFID development and early adoption

• 1980s – Commercial applications enter mainstream

• 1990s – Emergence of standards, RFID widely deployed

• 2000s – Over 350 direct reference patents, vast number of suppliers

SOURCE: Landt, Jeremy. Shrouds of time, AIM 2001

The RFID systemThe RFID system• Main Components

– A reader (interrogator) with an antenna and an external interface (e.g., to a computer)

– A transponder (tag) with a chip and an antenna

A chip

Antenna

A TagA Tag

A ReaderA Reader

A ComputerA ComputerExternal Interface

Reader’s Antenna

(also called as an Interrogator)

How does it works?How does it works?

• Reader gets and executes commands from the back-end system

• Reader emits radio frequency (RF) waves via its antenna

• Waves travel through air and “energize” a passive transponder

• Tag responds and transmits data signal via its antenna

• Reader captures the tag data signal

• Reader processes data signal

• Reader delivers the processed information to the back-end system

RFID tagsRFID tags

2 common types:

Active Passive

Powered by battery Powered by reader

Range up to hundred meters Range up to a few meters

Large memory size Small memory size

Relatively expensive Relatively cheap

Relatively large in size Relatively small

The IC chip The tag inlay

The tag antenna

A RFID paper label

RFID tagsRFID tags [cont’]

• Made up of three parts– Chip with memory that holds the intended information– Antenna, which is used to transmit information or in passive

tags, to harvest power– Packaging, which encases the chip and the antenna

• Memory configuration– Read-only (RO)– Write-once-read-many (WORM)– Read-write (R/W)

RFID TagsRFID Tags

Bottom Layer(Adhesive)

Inlet (RFID Tag)

Spacer(Protective Layer)

Top Overlay(printed layer)

Construction

RFID UHF TagsRFID UHF Tags

ALL-9238 tag"SquiggleT" antenna design; Approximate Size: 95mm x 10mm; Small UHF form factor

ALL-9250 tag”I2” antenna design; Approximate Size: 134mm x 13mm; high gain in a controlled orientation

ALL-9254 tag"M" antenna designApproximate Size: 95mm x 30mmVery high gain

source: www.alientechnology.com/

EPC RFID ClassesEPC RFID Classes• Class 0 Tags – Read Only

E.g Matric

• Class 1 Tags – WORME.g Alien

• Class 0+ - Read/WriteE.g Matrics, Impinj

• Class 2 – Read/Write

• Class 3 – Semi active, with sensorsE.g Alien, Powerpaper(EM)

• Class 4 – Active Tag

RFID tagsRFID tags [con’t]

• Size of the silicon chip is small

• Size and design of the antenna depend on the required performance

For glass bottle*

For generic cartoon* (high performance)

For wood pallet*

SOURCE: Alien Technology SOURCE: Matrics Technology

For generic cartoon*

RFID System FrequenciesRFID System Frequencies

• Frequency bands used

• <135KHz (low frequency, LF)

• 13.56MHz (high frequency, HF)

• 868MHz to 915MHz (Ultra-high frequency, UHF)

• 2.45GHz, 5.8GHz (microwave)

Low Frequency (LF) Low Frequency (LF) (135 KHz)(135 KHz)

• Use inductive coupling

• Typically passive, read-only, or read-write transponders

• Requires a longer, more expensive antenna

• Has shorter read ranges and typically larger transponder sizes than higher frequency ones

• The least susceptible to performance degradations from metals and liquid

High Frequency (HF)High Frequency (HF) (13.56 MHz)(13.56 MHz)

• Use inductive coupling

• Typically passive, read-only, read-write, or WORM (write once, read many) transponders

• Less expensive and smaller than LF transponders

• Lower data rates when compared with higher frequency ones

• Commonly used in contact-less smart cards

• Good penetration through non-conductive materials and nonconductive liquids

Ultra-High Frequency (UHF)Ultra-High Frequency (UHF)

(868 MHz and 915 MHz)(868 MHz and 915 MHz)• Use far field coupling

• Active and passive, read-only, read-write, or WORM transponders

• Longer read range (up to 5 meters), higher data transfer rate

• Less expensive than LF and HF transponders

• Good penetration through non-conductive materials and non-conductive liquids

• Provides a good balance between range and performance, especially for multiple transponder reading

Microwave Microwave (2.45 GHz, 5.8 GHz)(2.45 GHz, 5.8 GHz)

• Use far field coupling

• Active and passive, read-only, read-write, or WORM transponders

• Similar characteristics to UHF transponders, but with faster read rates

• Cost is often twice as much or more than lower frequencies

• Microwave heating on water

• Reflected by metals and other conductive surfaces; offers the most directional signal

• Frequency used by other applications, e.g. WiFi, microwave oven

Frequency band

Operating range*

Applications Benefits Drawbacks

LF, < 135MHz < 0.5m •Access control

•Animal tracking

•Product authentication

Works well around water and metal

•Short read range

•Slower read rate

HF, 13.56MHz <1m •Smart cards

•Library books

•Airline baggage

Low cost Higher read rate than LF

UHF,

860MHZ to 930MHz

<4m •Pallet tracking

•Carton tracking

•Parking lot access

EPC standard built around this frequency

Does not work with items of high water or metal content

Microwave

2.4GHZ

<1m •Airline baggage

•Electronic toll collection

Most expensive

Fastest read rates

* Operating range depends on reader power and operating environment

RFID Frequency ComparisonRFID Frequency ComparisonFrequency Advantages Drawbacks

>135 KHz

Proven technologyNo Regulation problems.Metal and water tolerant.Animal traceability

Slow data transferLarge tag for 1m+Cost and packaging

13.56 MHz

Proven technology Reasonable tag sizeMany suppliersCost

Problems such as detuning Poor metal toleranceStandards: 14443 15693 18000...

Long range is out of ISO

UHF

869-930 MHz

Best operating rangeChoose for EPC solutionCost targetthe “only” long range choice

Poor metal tolerancePoor water toleranceNon mature market

2.45 GHzSmallest tagHigh data rate

Short range !RegulationInterference problems

Benefits of RFIDBenefits of RFIDTechnical Features:

• No line of sight, from a distance, of varying orientation

• Read and write capabilities – change data at any time and data capacity is higher

• Reusable

• Multiple tags can be read in fast succession

• Embeddable into any non-metallic product – opaque is ok

Benefits of RFIDBenefits of RFIDBusiness Perspective:

• Reduction of direct labor – data capturing without human interaction

• Protection of assets; brand protection – authentication

• Single identifiable track-and-trace in real-time

• Inventory costs savings

Follow the leaders:• Mandate (e.g Wal-Mart, DOD, Tesco, Metro)

Drawbacks of using RFIDDrawbacks of using RFID• Unregulated: Operates in the ISM1 (industrial, scientific and medical) band

that requires no operator’s license.

• Security: Tag signals can be read by any equipment within range

• Interference: occurs when more than one reader is transmitting

(partitioning is then required)

• Interference: occurs when more than one tag is responding (anti-collision

mechanism is needed)

• Privacy: track and trace capability

1. http://www.itu.int/ITU-R/terrestrial/pub-reg/faq/index.html#g013

Factors that affect operating Factors that affect operating distancedistance

• The radio frequency used

• Power emitted by the reader

• The working environment

• Sources of radio interference

RFID ConstraintsRFID Constraints

Metal Interference

Metal heavily influences LF and HF systems. The reflected induction field reduces the transmitting field’s power. Near the surface, there is no signal at all.

Also, with HF Systems the antenna will run out of tune due to metal influence.

UHF waves can't penetrate metal and will be reflected as well, but the interferences can be mastered.Active and semi-active systems are not affected.

Metal

B-

Fie

ld

~Source: Sato

RFID ConstraintsRFID Constraints

Water Interference

Water has only a small influence on LF and HF systems,

but a heavy influence on UHF systems.

The RF-wave makes the water’smolecular structure oscillate.

This creates heat energy.

The microwave!

H2O

Source: Sato

RFID System ConsiderationsRFID System Considerations

• Determine the required read distance

• Select a suitable tag antenna design for the specific application

• Select a suitable system frequency

• Follow standards and government regulations

• For multiple tag reading in same field, select a suitable reader with anti-collision

• Select a suitable reader antenna arrangement for orientation sensitive applications

• A hardware setup can be affected by the working environment

Source: SATO

RFID – why not now?RFID – why not now?Varying standards – incompatibility; costs; cross-border

US, Canada125KHz13.56MHz902-928MHz

EU Countries125KHz13.56MHz868-870MHz

Japan125KHz13.56MHz950-956MHz

Different UHF ISM bands – cross-border issueDifferent UHF ISM bands – cross-border issue

ApplicationsApplications

• Inventory control

• Theft prevention (EAS)

• Track and trace of products (in food and pharmaceutical industries)

• Express checkout

• Smart cards

• People tracking (RFID tag implant)

• Tracking animals/fish– RFID ear tags for cattle.

– RFID under-skin smart tags are being used for horses or pets.

– In Singapore, SANC pioneered the application of RFID tags incorporating EAN-128 system to identify the endangered Arowana Fish.

RFID ApplicationsRFID Applications

Source: SatoSource: Sato

RFID ApplicationRFID Application

Other Possible ImplementationsOther Possible Implementations

• Sewing RFID tags directly into fabric fibers in the clothing industry

• Protecting sensitive documents (US passports will have RFID tags from 2005 onwards)

• Counterfeit control1

• Baggage trackers2

1. www.informationweek.com/story/showArticle.jhtml?articleID=18311407

2. www.usatoday.com/travel/news/2004-04-19-high-tech-bag-tracking_x.htm

Other Possible ImplementationsOther Possible Implementations

EPC GlobalEPC Global

“EPCglobal is leading the development of industry-driven standards for the Electronic Product Code™ (EPC) to support the use of Radio Frequency Identification (RFID) in today’s fast-moving, information rich trading networks. We are a member-driven organisation comprised of leading firms and industries focused on creating global standards for the EPCglobal Network™.”

• EPC Standards

• EPCglobal Network

http://www.epcglobalinc.org

See the “Video: The Basics of RFID and EPC”

EPC Tag Data Standards Specific encoding schemes for a serialized version of the EAN.UCC Global Trade ItemNumber (GTIN®), the EAN.UCC Serial Shipping Container Code (SSCC®), the EAN.UCC Global Location Number (GLN®), the EAN.UCC Global Returnable Asset Identifier (GRAI®), the EAN.UCC Global Individual Asset Identifier (GIAI®), and a General Identifier (GID).

UHF Class 0 SpecificationsCommunications interface and protocol for 900 MHz Class 0

UHF Class 1 SpecificationsCommunications interface and protocol for 860 - 930 MHz Class 1

HF Class 1 Specifications Communications interface and protocol for 13.56 MHz Class 1

Reader Protocol Communications messaging and protocol between tag readers and EPC compliantsoftware applications

Savant Specification Specifications for services Savant performs for application requests within theEPCglobal Network

Object Name Service Specification Specifications for how the ONS is used to retrieve information associated with aElectronic Product Code (EPC)

Physical Markup Language Core SpecificationSpecifications for a common vocabulary set to be used within the EPC global Networkto provide a standardized format for data captured by readers

EPC Global SpecificationsEPC Global Specifications

EPC (Electronic Product Code)EPC (Electronic Product Code)96-bits

e.g., Manufacturer 28 bits (>268 million)

e.g., Product 24 bits (> 16 million)

e.g., Serial Number 36 bits (> 68 billion)

ConclusionConclusion• RFID can be used for a wide range of applications

• RFID is one of many established information technologies that are making life safer & easier

• Consumers benefit from better services, based on their behavior, desires and needs

• Standardization will drive the adoption rate in the near future

• Wider adoption will be expected if issues like tag price, consumer privacy are solved