RFID Basics

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Transcript of RFID Basics

What is it?

(And why should you care?)

RFID – What is it? Radio Frequency Identification

Three parts to an RFID implementation:Tag (chip and antenna)ReaderDatabase & software

Tag holds unique data – a serial number and/or other unique attributes of the item

RFID History First Bar code patents – 1930s First use of RFID device – 2nd world war – Brittan used RFID-like

technology for Identify- Friend or Foe Harry Stockman October 1948 Paper – Communication by means of

reflected power ( The proceedings of the Institute of Radio Engineers) First RFID Patent - 1973 Auto-ID center founded at MIT – 1999

Standardization effort taken over by EPC Global (Electronic Product Code) Current thrust primarily driven by Wal-Mart and DoD

Automate Distribution:○ Reduce cost (man power, shipping mistakes)○ Increase sales (keep shelves full)○ DoD Total Asset Visibility Initiative

Basic Tag Operational Principles

NN

SS

TAG

Rea

der

Rea

der

TAG

BackscatterBackscatter

• Near field (LF, HF): inductive coupling of tag to magnetic field circulating around antenna (like a transformer)• Varying magnetic flux induces current in tag. Modulate tag load to communicate with reader• field energy decreases proportionally to 1/R3 (to first order)

• Far field (UHF, microwave): backscatter. • Modulate back scatter by changing antenna impedance• Field energy decreases proportionally to 1/R

• Boundry between near and far field: R = wavelength/2 pi so, once have reached far field, lower frequencies will have lost significantly more energy than high frequencies• Absorption by non-conductive materials significant problem for microwave frequencies

Inductive CouplingInductive Coupling

Why Now! Recent improvements in tag and reader

technologyBetter performanceEasier deployment and maintenanceBetter use of existing infrastructure and

technologies Improvements in tag and reader manufacturing

Cheaper tags and readers Industry standardisation

EPCglobal and ISO

RFID Uses

Retail & Distribution Contactless Payment Keyless Entry Livestock Tagging Pharmaceuticals Logistics Assets (containers, trailers) Pet Identification

Bar Codes on Steroids

“RADIO FREQUENCY identification (RFID) tags are like bar codes on steroids; they're to traditional SKUs what Robocop was to your ordinary cop on the beat.”

- CIO Magazine

RFID Benefits

More information Individual item data & tracking

Fast No contact No line of sight MilisecondsSimultaneous read of multiple items

RFID Tag Attributes

Active RFID Passive RFIDTag Power Source

Internal to tag Energy transferred using RF from reader

Tag Battery Yes No

Required signal strength

Very Low Very High

Range Up to 100m Up to 3-5m, usually less

Multi-tag reading 1000’s of tags recognized – up to 100mph

Few hundred within 3m of reader

Data Storage Up to 128 Kb or read/ write & search

128 bytes of read/write

Passive RFID Tags

EXAMPLE: “Traditional” tags used in retail security applications

Tag contains antenna and a small data chip

Tag is powered by the electromagnetic field generated in doorways, reflecting back a weak signal containing data

Active Tags

EXAMPLE: military; transportation assets

Battery Powered tagsGreater range – 100mMore information – KbytesCan integrate sensors

○ Temperature, GPS

More expensive Shorter life span

What Constitutes an What Constitutes an RFID System?RFID System?

One or more RF tags

Two or more antennas

One or more interrogators

One or more host computers

Appropriate software

TagInsert

Antenna Reader

Firmware

Customer’sMIS

Host

ApplicationSoftware API

TCP/IP

Power

~

Asset

Asset/Tag

RFID System RFID System ComponentsComponents(block diagram)(block diagram)

RFID OperationRFID OperationSequence of CommunicationSequence of Communication• Host Manages Reader(s) and Issues Commands• Reader and tag communicate via RF signal• Carrier signal generated by the reader (upon request

from the host application)• Carrier signal sent out through the antennas• Carrier signal hits tag(s)• Tag receives and modifies carrier signal

– “sends back” modulated signal (Passive Backscatter - FCC and ITU refer to as “field disturbance device”)

• Antennas receive the modulated signal and send them to the Reader

• Reader decodes the data– Results returned to the host application

RFID OperationsRFID Operations

What is RFID? -- The What is RFID? -- The TagsTags

Tags can be read-only or read-write Tag memory can be factory or field programmed,

partitionable, and optionally permanently locked Bytes left unlocked can be

rewritten over more than100,000 times

What is RFID? -- The What is RFID? -- The ReadersReaders

Readers (interrogators) can be at a fixed point such asEntrance/exitPoint of saleWarehouse

Readers can also be mobile -- tethered, hand-held, or wireless

RFID Readers Readers

Contains electronics, Tx, Rx and controlConnected to antenna(s)

○ mostly external

Energise tags (passive tags)Commands tags (wake up active tags,

enables management of the tag population)

Receive tag replies

RFID Readers

Host CPUApplicationDo something with the tag informationPotential to generate massive amounts of

dataOnce installed it costs virtually NOTHING to

read a tag!Real time data => real time decisionsOHIO (Zero Human Involvement

Operations)** Term defined by John Greaves, CHEP International

RFID System BasicsRFID System Basics

• How far?

• How fast?

• How many?

• How much?

• Attached to and surround by what?

How far, how fast, how How far, how fast, how much, how many, much, how many, attached to what?attached to what?

Frequency Regulation Range Data Speed Comments

125-150 kHz Basically unregulated Å 10 cm LowAnimal identificationand factory datacollection systems

13.56 MHzISM band, differingpower levels and dutycycle

< 1mLow tomoderate

Popular frequency forI.C. Cards (SmartCards)

433 MHzNon-specific ShortRange Devices (SRD),Location Systems

1 Š 100 m ModerateAsset tracking for U.S.DoD (Pallets)

860-930 MHz

ISM band (Region 2);increasing use inother regions,differing power levelsand duty cycle

2 Š 5 mModerate tohigh

EAN.UCC GTAG,MH10.8.4 (RTI),AIAG B-11 (Tires)

2450 MHzISM band, differingpower levels and dutycycle

1 Š 2 m HighIEEE 802.11b,Bluetooth, CT,AIAG B-11

Status Today

Issue #1: RFID Mandate Madness But will suppliers make the right choices?

Status Today

Issue #2: Lack of worldwide tag, reader, data standards Companies may later have to scrap choices

○ EPCglobal trying to solve○ China a wild card

Status Today

Issue #3: Tag costs too high Goal is 5¢ tag; can’t afford

$2 tag on 99¢ item Biggest limit on widespread

business use

Status Today

Issue #4: Lack of Software What to do with all that data?

Problem: “Petabytes” Answer: “Middleware”

Status Today

Issue #5: Privacy concerns Item level tagging Tagging people

“Mark of the Beast”

Urban legend

“Andrew Jackson’s Exploding Eyeball”

Urban legend

ApplicationsApplications

Portal Portal ApplicationsApplications

Bill of LadingMaterial Tracking

Portal ApplicationsPortal Applications

Limited number items at forklift speeds8’ X 10’ doorwaysElectronic receipt & dispatchWrong destination alertElectronic markingPallet/container item tracking

Conveyor / Assembly Conveyor / Assembly LineLine

Read / Write OperationsHigher Accuracy than Bar Code

Hand Held Application Hand Held Application CategoriesCategories

Wireless Batch

Fixed Station

Shipping ValidationShipping Validation

Tote/Box/Unit Level Inventory

Intelligent LabelsIntelligent Labels

The HazMat LabelThe HazMat LabelSHIP TO: SHIP FROM:

COMMANDING OFFICER DDSP SUSQUEHANNA, PA 15230

CHEMICAL SUPPLIER CHEMICAL COMPANY INSTITUTE, WV 23456

TCN:

NSN:

CAGE:

MSDS #:

GTIN:

HCC:

AHRIST DATA:

AWHGEAA$0F00090XX

5310011987585

AWHGE 00098756100013CHEM WT:

ABCDE 10000A1

HazMat Smart HazMat Smart LabelLabel Low power > long range 1024 bit memory Read/write/lock on 8 bits Advanced protocol

Efficient multi-id Lock data permanently 12 ms/8 byte read 25ms/byte write Group select Broadcast write 40 tags/second Anti-collision

The Future

"Imagine an Internet of things, where everyday objects, rooms, and machines are connected to one another and to the larger digital world.”

- Business 2.0

RFID Journal rfidjournal.com

InformationWeek informationweek.com

RFID Weblog rfid-weblog.com

Don’t Forget! “RFID in the Supply Chain”

19 November 2004 Martin Center