Introduction to RFIDIntroduction to RFID

Vlad KrotovVlad Krotov

DISC 4397 – Section 12977DISC 4397 – Section 12977 University of HoustonUniversity of Houston

Bauer College of BusinessBauer College of BusinessSpring 2005Spring 2005

Some links…

• www.rfidjournal.com

• www.computerworld.com

• www.rfidusa.com

• RFID Handbook

• www.uh.edu/gartner

Auto-ID Technologies

BiometricSystems

Smart Cards

RFID

OpticalCharacter

Recognition(OCR)

BarcodeSystems

Auto-ID

Definition

• RFID (Radio Frequency Identification) is a technology that enables the electronic and wireless labeling and identification of objects, humans and animals

RFID Principal System Components

• Tag (Transponder)– Chip– Antenna

• Reader (Interrogator)– RF Module (Transmitter and Receiver)– Control Unit– Antenna– Several Interfaces (RS 232, RS 485, etc.)

• Host Computer– Middleware

RFID System Architecture

EPC RFID Architecture

EPC RFID System Architecture

Carrier Frequencies

• What is frequency?– Refers to the property of radio waves used to

transmit data– Roughly speaking, it is the intensity of waves

used to transmit information

Carrier Frequency

• RFID systems may use a particular frequency band depending on:– Application– Legislature– Cost considerations

Frequency BandsFrequency Band Characteristics Typical

Applications

Low

100-500 kHz

Short to medium read range, inexpensive, low reading speed

Access control

Animal/Human identification

Inventory Control

Medium

10-15 MHz

Short to medium read range

Potentially inexpensive

Medium reading range

Access Control

Smart Cards

High

UHF: 850-950MHz

Microwave: 2.4 – 5.8 GHz

Long read range

High reading speed

Line of sight required (Microwave)

Expensive

Railroad car monitoring

Toll collection systems

Coupling

• 100kHz – 30 MHz – inductive coupling

• HF and Microwave systems use electromagnetic coupling

Coupling

Frequency and bandwidth

• Frequency is of primary importance when determining data transfer rates (bandwidth)

• The higher the frequency, the higher the data transfer rate

Range

• Range – the working distance between a tag and a reader

Range

Range and Power Levels

• The range that can be achieved in an RFID system is determined by– The power available at the reader– The power available within the tag– The environmental conditions and structures

• More important at higher frequencies than at lower frequencies

– 100-500mW

Material Propagation

• The absorption rate for water and other non-conductive substances is lower by a factor of 100 000 at 100 kHz than it is at 1 GHz

• LF systems are primarily used due to their high propagation of substances

Electromagnetic Interference

• What is electromagnetic interference?

• LF (inductive coupling) RFID systems suffer from electromagnetic interference more than UHF and Microwave

• Microwave systems are more likely to be used in manufacturing (auto-industry)

Tags Characteristic

• Means by which transponder is powered

• Data carrying options

• Data read rates

• Programming options

• Physical forms

• Costs

Active and Passive Tags

• Active tags– Powered by an internal battery– Finite lifetime (because of battery)– Greater range– Better noise immunity– Higher data transmission rates

Active and Passive Tags

• Passive tags– Operate without battery– Derive power from the field generate by the

reader– Less expensive– Unlimited life– Subject to noise– Require more powerful readers– Orientation sensitivity

Data Carrying Options

• A tag can contain– An identifier

• 1bit – 128 bits

– Portable data files• Example: 64 K

Data Read Rate

• Data read rate is linked to frequency– The higher the frequency, the higher the read

rate

Data Programming Options

• Read-only– Cheap

• Write once read many (WORM)

• Read/write– Expansive

Why Use Read/Write Tags?

• Greater flexibility– Customers may change requirements– Standards may change

• Database dependence– Ownership issues– Lag times

• High risk applications

Tag Physical Forms

• Disk and Coins – can be attached to an item by a fastening screw

Tag Physical Forms

• Mount-on-Metal – special construction minimizes impact of metal in terms of interference

Tag Physical Forms

• Keys or Key Fobs, Watches – access control

Smart Labels

• A bar code can be printed on an RFID label

Tag Physical Forms

• Glass Transponders can be implanted under skin

What’s so special about RFID?

• Unifying Auto-ID technology

• Line of sight is not required

• Longer read ranges

• Faster: hundreds of items can be scanned in one read

RFID vs. Barcodes

Principles of Profitable RFID Use

• Bar codes are unfeasible– Example: rail cars

• Damage• Speed

• Counting Processes – Greater speed– Saves manual labor

Principles of Profitable RFID Use

• Personal responsibility doesn't match the enterprise value of data collection– Example: a big retailer working with a small

supplier

• The data collection process is relatively chaotic– Example: Battlefield– Making libraries chaotic

Principles of Profitable RFID Use

• The exact configuration of goods must be maintained– Example: Auto industry

• Data must be collected from consumers outside of the retail– Warning: Privacy Concerns

RFID Evolution (Gartner, 2003)

RFID Growth

• Several market research firms predict that ~2007 RFID market will reach ~$3 billion

Questions?