fcc rfid workshop rfid discussions september 7, 2004
DESCRIPTION
FCC RFID Workshop RFID Discussions September 7, 2004. Kevin Powell, Symbol Technologies. Pilots with eight key suppliers. Wal-Mart's RFID-Using Suppliers to Exceed 100. eWeek June 14, 2004. Convergence around the Electronic Product Code (EPC) as the standard. - PowerPoint PPT PresentationTRANSCRIPT
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FCC RFID Workshop RFID DiscussionsSeptember 7, 2004
Kevin Powell, Symbol Technologies
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RFID Market Direction
Convergence around the Electronic Product Code (EPC) as the standard
Wal-Mart's RFID-Using Suppliers to Exceed 100
Pilots with eight key suppliers
eWeek June 14, 2004
Defense Department will require its suppliers to put RFID tags on shipments by January 2005 to better manage its inventory. Aviation Week
EPC Pallet and case tagging mandates – PASSIVE tags
Defining the Gen 2 Standard
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The Goal is Asset Visibility … Everywhere!
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EPC Standards Glossary
Class 0 (available): Generation 1, protocol 0 Factory programmed ID
Class 1 (available): Generation 1, protocol 1 Write Once ID
UHF Generation 2 (future): Single Gen2 protocol Variety of memories & features First products in 2005
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Readers and Antennas
AR400 Reader
High Performance Antenna
General Purpose Antenna
SR400 Reader
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Handheld with RFID
Supports:
Same ruggedness and ergonomic as the MC-9000G
Antenna (front-mounted)and additional electronics add the ability to read and write either EPC Class 0 or Class 1 RFID tags
Integrated wireless networking
RFID 2D bar code
“all in one”
1D bar codes &
simultaneously
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EPC-Compliant RFID Tags
Plastic Tag Carton Tag
Glass TagConcrete Tag
Plastic Bottle Tag
Generic TagVariety of tags for different materials and applications Class 0/0+
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Basics - RFID System
A tag stores information and exchanges it by radio signal
Passive RFID Tag
Reader commands the tag & simultaneously listens for responses
RF modulator
MemoryPower recovery
Digital logic
Radio Signal
RFID Protocols
} Three EPC Communication Protocols for UHF
EPC Class 0 (Invented by Matrics)EPC Class 1 (Invented by Alien
Technologies)EPC Gen2 under development
RF demodulator
Oscillator
All in 10 microwatts!
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Passive RFID System Design
Passive Tag Constraints Battery-less – RF field powered ONLY, thus: Total consumed power < 10 W (10M range), and Simple demodulator (amplitude – 1bit/Hz style) Simple modulator (1 transistor – square wave out) Backscatter (modulated RCS) only Tx method
Passive Tag Results Very wide band response (effective antenna BW)
in receiver as well as backscatter(but at low levels) Confined to relatively inefficient reader modulation
encoding methods (simple tag demod).
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Passive RFID System Design
Reader Constraints Must energize tag (transmit) while in receive mode = Receive –50dBm while transmitting +30dBm Avoid noise sources
– Reader transmit & receive circuitry– Other backscatter sources, ie fluorescent lighting
Reader Results Extremely low noise design necessary to properly
receive tag signals while transmitter is on. Detect and avoid other high power RF devices. Shift receiver away from noise sources.
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RFID Frequency Sources
Reader TxReader CW
Fluorescent 20-40kHz
Tag -
baseb
and
Tag – Gen2 Subcarriers
Channel Edge
Channel Edge
Tag – Class 0 Subcarriers
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Passive RFID Trends
Better tag designs/protocols = lower power
Year Tag Dist Rdr pwr Tag field Rdr Rx
2000 10’ +30dBm 600W -45dBm
2002 25’ +30dBm 100W -60dBm
2004 50’ +30dBm 25W -75dBm
2006 75’ +30dBm 11W -82dBm
2008 100’ +30dBm 6W -87dBm
Note – Fluorescent interference approx –60dBm
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Gained Knowledge
Reader signals interfere with tag signals at thousands of feet separation.
Reader signals interfere with other reader transmissions at less than 100 feet.
80-100 dB range between Reader and Tag leads design to a separation of disparate power levels such that: Reader signals ONLY contend w/ other readers Tag signals ONLY contend with other tags
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Conclusions, Requests
As technology improves tag distances, the impact of noise (self, and fluorescent) becomes severe; the available technology is near the limit.
Technology improvement comes on the heels of the ability to remove the tag response from noise.
Request - allow readers on even channels, tag response on odd channels (or similar) as an optional channel use model.
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Thank You
Questions?
?