22-1©2008 Raj JainCSE574sWashington University in St. LouisRadio Frequency Radio Frequency Identification (RFID)Identification (RFID)Raj Jain Washington University in Saint LouisSaint Louis, MO [email protected]/Video recordings of this lecture are available at:http://www.cse.wustl.edu/~jain/cse574-08/22-2©2008 Raj JainCSE574sWashington University in St. LouisOverviewOverview! What is RFID?! RFID: Applications! RFID Tags and RFID Readers! Reader-Tag Coupling! RFID Standards! Security Issues22-3©2008 Raj JainCSE574sWashington University in St. LouisWhat is RFID?What is RFID?! Radio Frequency Identification! Reader queries using RF, ID sends its ID using RF! Competes with Bar Code, Magnetic stripes, Magnetic Ink Character Recognition (MICR) on Bank Checks22-4©2008 Raj JainCSE574sWashington University in St. LouisRFID: ApplicationsRFID: Applications! Pioneered by British during World War II to identify aircrafts! 1960's US Government started using RFID on nuclear and hazardous materials! Garage door openers use RFID! Implants in human, horses, fishes, animalsAnimal ID Standards ISO 11784 and 11785 use RFID! Automatic Toll Collection! Access control, Equipment Tracking! All shipments to DoD must be RFID tagged.! Sensor+RFID can be used to monitor products inside sealed shipping containers22-5©2008 Raj JainCSE574sWashington University in St. LouisApplications (Cont)Applications (Cont)! Warranty information on RFID tags! Smart medical cabinets remind patients to take medications and call doctors if missed! Retail loss prevention! No need to unload grocery carts for checkout22-6©2008 Raj JainCSE574sWashington University in St. LouisRFID TagsRFID Tags! Tag = Antenna, Radio receiver, radio modulator, control logic, memory and a power system! Power Source:" Passive Tags: Powered by incoming RF. Smaller, cheaper, long-life. Approx range 5m." Active Tags: Battery powered. Can be read 100 ft away. More reliable reading." Semi-Passive tags: Transmit using 'Backscatter' of readers' RF power. Battery for logic. Range like passive. Reliability like active.22-7©2008 Raj JainCSE574sWashington University in St. LouisTags (Cont)Tags (Cont)! Size:" Hitachi mu-chip is 0.4 mm on a side. Designed to be embedded in paper documents. Can be read within a few cm." Verichip makes tags the size of grain of rice. Designed to be implanted in humans. Identify patients." Semi-passive RFIDs used in E-Z Pass toll collection are paperback book size. 5-year battery.! Security:" Promiscuous Tag: Can be read by any reader. Most tags." Secure Tag: Need reader authentication. Usually manual passwords.22-8©2008 Raj JainCSE574sWashington University in St. LouisTags (Cont)Tags (Cont)! Components:" Simple tags with Serial #. 96-bit block of read-only storage (ROM)." Read-write memory." Tags may have embedded sensors (tire pressure sensor)! Kill Feature: Special code causes the chip to stop responding.! Multiple tags can interfere ⇒ Need a singulation protocol ⇒ Reader interrogates one tag at a time.22-9©2008 Raj JainCSE574sWashington University in St. LouisRFID ReadersRFID Readers! Sends a pulse of radio energy and listens for tags response! Readers may be always on, e.g., toll collection system or turned on by an event, e.g., animal tracking! Postage stamps size readers for embedding in cell phonesLarger readers are size of desktop computers! Most RFID systems use License-exempt spectrum! Trend towards high-frequencyBand Frequency λ Classical Use LF 125-134.2 kHz 2,400 m HF 13.56 MHz 22 m Animal tagging and keyless entry UHF 865.5-867.6 MHz (Europe)915 MHz (USA) 950-956 MHz (Japan) 32.8 cm Smart cards, logistics, and item management ISM 2.4 GHz 12.5 cm Item Management22-10©2008 Raj JainCSE574sWashington University in St. LouisReaderReader--Tag CouplingTag Coupling! Passive tags have capacitor to store energy for replying (TDD)" Can respond on another frequency while reader is still transmitting (FDD)! Near-Field = Within a few wavelengthFar-field = Beyond a few wavelengths! Low-Frequency (large λ) system operate in near-fieldHigh-Frequency and UHF system operate in far-field1. Inductive Coupling: In near-field" Both Antennas are coils (like transformers)" Reader sends a AM/FM/PM modulated wave. " Tag responds by varying its load on the reader.22-11©2008 Raj JainCSE574sWashington University in St. LouisCoupling (Cont)Coupling (Cont)2. Back Scatter: In far-field" Reflecting the energy back. " Tag changes its reflection to respond.3. Capacitive Coupling: " Charged plates as antennas on readers and tags" Can be easily printed.Chip22-12©2008 Raj JainCSE574sWashington University in St. LouisRFID RangeRFID Range! Reading range depends upon the transmitted power, antenna gains, frequency, reader receiver sensitivity.! Affected by the environment: Metal objects (aluminum foil), Water (Wetness, salt water)22-13©2008 Raj JainCSE574sWashington University in St. LouisRFID StandardsRFID Standards! ISO/IEC JTC1/SC31/WG4 " Automatic Identification and Data Capture Techniques" ISO (International Organization for Standardization) and" IEC (International Electro-Technical Commission)" Joint Technical Committee number one, JTC 1 (ISO/IEC)" Subcommittee SC 31 ! Electronic Product Code (EPCGlobal) - Industry consortium! JTC 1/SC 17 Identification Cards and related devices! ISO TC 104 / SC 4 Identification and communication! ISO TC 23 / SC 19 Agricultural electronics! CEN TC 278 Road Transport and Traffic Telematics" Comité Européen de Normalisation(European Committee for Standardization)22-14©2008 Raj JainCSE574sWashington University in St. LouisRFID Standards (Cont)RFID Standards (Cont)! CEN TC 23/SC 3/WG 3 Transportable Gas Cylinders -Operational Requirements - Identification of cylinders and contents! ISO TC204 Transport Information and Control Systems! American National Standards Institute (ANSI) X3T6: RF Identification! European Telecommunications Standards Institute (ETSI)! ERO European Radio communications Office (ERO)! Universal Postal Union ! ASTM International (Testing Materials)22-15©2008 Raj JainCSE574sWashington University in St. LouisSecurity IssuesSecurity Issues! Unauthorized Reading: " Competitors can scan closed boxes and find out what is inside" Someone can read your RFID enabled credit card! Unathorized Writing:" Can change UPC/price of an item" Can kill a tag! Solution: Reader authentication. " Passwords can be sniffed.22-16©2008 Raj JainCSE574sWashington University in St.
View Full Document
Unlocking...