Presentation on theme: "1 FCC RFID Workshop RFID Discussions September 7, 2004 Kevin Powell, Symbol Technologies."— Presentation transcript:
1 FCC RFID Workshop RFID Discussions September 7, 2004 Kevin Powell, Symbol Technologies
2 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
4 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
5 Readers and Antennas AR400 Reader High Performance Antenna General Purpose Antenna SR400 Reader
6 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
7 EPC-Compliant RFID Tags Plastic TagCarton Tag Glass Tag Concrete Tag Plastic Bottle Tag Generic Tag Variety of tags for different materials and applications Class 0/0+
8 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 Memory Power 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!
9 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).
10 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.
11 RFID Frequency Sources Reader Tx Reader CW Fluorescent 20- 40kHz Tag - baseband Tag – Gen2 Subcarriers Channel Edge Tag – Class 0 Subcarriers
12 Passive RFID Trends Better tag designs/protocols = lower power YearTag DistRdr pwrTag fieldRdr Rx 200010’+30dBm 600 W -45dBm 200225’+30dBm 100 W -60dBm 200450’+30dBm 25 W -75dBm 200675’+30dBm 11 W -82dBm 2008100’+30dBm 6W6W -87dBm Note – Fluorescent interference approx –60dBm
13 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
14 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.