RFID: Technology and Applications

By: Sweta DargadAssistant Professor

ITM Universe

The Wave of the Future

Outline

• History of RFID• Types & Systems• Current Uses• Future Applications• Controversies

What is RFID?• A technology that employs a microchip with

an antenna that broadcasts its unique identifier and location to receivers.

• Employs a microchip called a smart tag, broadcasts unique 96-bit identifier to receiver.

• Receiver relays the data to a computer.

Eth

erne

t

RFIDReader

RFID Tag RF Antenna Network Workstation

RFID vs. Bar Codes

• Does not require human to manually pass item

over scanner.• More accurate inventory count.• Can be incorporated into product, person,

animal.• Can track each individual item.

History of RFID• 1939

– IFF Transponder: Identification, friend or foe (IFF) is an identification system designed for command and control. It enables military and national (civilian air traffic control) interrogation systems to identify aircraft, vehicles or forces as friendly and to determine their bearing and range from the interrogator

– Used by allies in WWII• 1945

– Leon Theremin made “The Thing”, also known as listening device

– Espionage tool for Soviet Union

History cont.

• 1973– Claims U.S. patent was first true ancestor

• 1980– Retail– Use of RFID in tracking and access applications

appeared– Price, color, date of purchase

RFID Tags• Contains two main parts:

– Silicon chips– Antennas

• Components enable tags to receive and respond to radio frequencies queries from RFID transceivers.

• Three types:– Passive– Semi-Passive– Active

RFID Tags cont.• Passive

– Have no internal power supply– Electrical current inducted in antenna by the incoming signal

proves power for integrated circuit in tag to power up and transmit response

– Very Small, Limited Range, Unlimited Life

• Semi Passive– Similar to passive tags, with the addition of a small battery– Battery powers the integrated circuit– Bigger, Longer Range, Limited Life

• Active– Have their own internal power source– Many operate at fixed intervals– Also called beacons (broadcast own signal)– Large ( coin), Much larger memories, Longer range

Tag block diagramAntenna

Power Supply

Tx Modulator

Rx Demodulator

Control Logic(Finite State machine)

MemoryCells

Tag Integrated Circuit (IC)

RFID readers• Reader functions:

– Remotely power tags– Establish a bidirectional data link– Inventory tags, filter results– Communicate with networked server(s)– Can read 100-300 tags per second

• Readers (interrogators) can be at a fixed point such as– Entrance/exit– Point of sale

• Readers can also be mobile/hand-held

RFID System Objects equipped with RFID tag

Tag contains transponder with digital memory chip.

Interrogator: an antenna packaged with transceiver and decoder. emits signal activating tag.

Reader detects activation signal, decodes the data on the tag’s silicon chip.

Data passed to host computer.

Growing Technology

• “Line of Sight” Technology• RFID superior over Barcode

– Elements and accidents can disturb or damage barcodes

• Best Buy, Wal-Mart, And Target began implementation– Efficient in ability to track & respond accordingly

Product Marketing – 75 years ago

You can have any color, as long as its black !

Product Marketing - Today

5

Add consumer flexibility, courtesy of robotics, computers …

Customer window into final stage of manufacturing

Need to ensure error-free, custom assemblyNeed inventory of components for the various customization options

Critical IssuesAssembly process controlInventory managementSupply chain integrationCustomer insight

Effect on manufacturing

Applications of RFID Manufacturing and Processing

Inventory and production process monitoring Warehouse order fulfillment

Supply Chain Management Inventory tracking systems Logistics management

Retail Inventory control and customer insight Auto checkout with reverse logistics

Security Access control Counterfeiting and Theft control/prevention

Location Tracking Traffic movement control and parking management Wildlife/Livestock monitoring and tracking

Current Uses• Wal-Mart now requires its

suppliers to use RFID tags on shipping crates and pallets to improve inventory management in the supply chain.

• Fed Ex bought RFID-enabled aircraft from Airbus to reduce maintenance time and costs.

• Cattle and farm animals are being tagged to improve tracking and monitoring of health.

Smart groceries enhanced

Track products through their entire lifetime.

Issues in Defense solved

• U.S. Department of Defense – to better track goods along supply chain (logistics and inventory).

• Electronic payment – credit card companies moving to RFID-enabled cards to increase efficiency and reduce time at point-of-sale for customer, merchant, and card issuer.

Some more smart devices• “Smart” appliances:

– Closets that advice on style depending on clothes available. – Ovens that know recipes to cook pre-packaged food.

• “Smart” products:– Clothing, appliances, CDs, etc. tagged for store returns.

• “Smart” paper:– Airline tickets that indicate your location in the airport.

• “Smart” currency:– Anti-counterfeiting and tracking.

• “Smart” people ??

The Future of RFID MedicalDrug Counterfeiting

Tracking & TracingMedical “Passports”

Foster Care SystemFood Chain Precautions

ShoppingCashier-less check out

and payment

Household TechnologySmart keysIntelligent washing

machinesMonitoring refrigeratorsIntelligent

ovens/microwaves

Controversy• Privacy

– Consumer Rights• Consumers should be informed if their products have

an RFID tag.

– Tracking of consumers (Profiling)• RFID chips withstand dirt and scratches and can be

scanned from distances upward of 25 feet.• Personal Information Leakage.• Drawing the Line – Need for Legislation?

– Who Should Regulate?

Controversy cont.• “Killing” of RFID Tags

– Tracking vs. the washing machine– Options of killing after purchase

• Medical– Implants/Personal Information

• Verichip is a tiny implantable chip that holds medical records

• Bracelets to track infants in medical wards and elderly in nursing homes.

– Used in animals for tracking.

Controversy cont.

• Medical– Health Risks

• Hard to remove once implanted.• Long term effects unknown.

• Religious– Mark of the Beast, etc.

• The implanted RFID chip is certain to inflame Christian fundamentalists, some of whom believe that such chips are the Satanic “mark of the Beast” predicted in Revelations 13:16 “And he causeth all, both small and great, rich and poor, free and bond to receive a mark in their right hand, or in their foreheads.”

RF effects of common materials

Communication protocols

ETSI EN 302 208 standard• Shared operation in band 865.0 – 868.0 MHz at

transmit powers upto 2 W ERP.– Operation in 10 sub-bands of 200 kHz.– Power levels of 100 mW, 500 mW and 2 W ERP.

• Mandatory “listen before talk” and “look before leap”.

865.7 MHz 867.5 MHz

FT

865.1 MHz 867.9 MHz

100 mW

867.7 MHz865.5 MHz

LT

FT

LT LT

FT

600 kHz 600 kHz600 kHz

2 W

FT

LT

500 mW

865.0 MHz 865.6 MHz 867.6 MHz 868.0 MHz

Reader Collision Problem

• Reader-Reader Interference• Reader-Tag Interference

Reader Collision and Hidden Terminal

• The passive tags are not able to take part in the collision resolution or avoidance, as in other wireless systems

• Consider: RTS-CTS for hidden terminal problem in 802.11– rfid: T is not able to send a CTS in response to an RTS from R

In case multiple readers try to read the same tag, the tag cannot respond selectively to a particular reader

TDMA based solution• Assign different time slots and/or frequencies to

nearby readers– Reduces to graph coloring problem (readers form vertices)

• Only reader to reader interference – Assign different operating frequencies

• Only multiple reader to tag interference – Assign different time slots for operation

• Both types of interference– First allot different time slots, then frequencies

Main Points

• Slowly becoming an industry standard• Speeds up the supply chain process• Easier to manage inventory• Continually evolving• Controversial technology

Questions for you….

• Define RFID technology?• When was RFID introduced?• What are two main reasons RFID is

controversial?• Name the three types of RFID tags?• How are they currently using RFID tags?• How is RFID Technology expected to effect

households?

Questions?