The ones we are using have a silicon die. When the tag receives a signal it activates the die and causes a change in impedance. The Transponder detects this change and reads the difference in the reflected signal. From what I have gathered this is still considered to be passive.
Josh From: [email protected] [mailto:[email protected]] Sent: Thursday, November 20, 2003 10:42 AM To: [email protected] Subject: RE: RFID tags I think the passive, dumb RF antitheft tags are simply 915 MHz dipoles with a diode at the center. The scanners pick up a harmonic generated when a 915 MHz field is applied. Don Borowski Schweitzer Engineering Labs Pullman, WA [email protected] Sent by: owner-emc-pstc@ma To jordomo.ieee.org "Joshua Wiseman" <[email protected]> cc 11/20/03 08:33 AM [email protected] Subject RE: RFID tags Please respond to [email protected] Not for sure. But it is my understanding that the passive tags are not subject to RTTE. We need someone who knows for sure to respond. Bob Heller 3M EMC Laboratory, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 ======================================================= "Joshua Wiseman" <JWiseman@printron To: <[email protected]> ix.com> <[email protected]> cc: <[email protected]> 11/20/2003 09:52 <[email protected]> AM Subject: RE: RFID tags Bob, Do you know anything about the 915MHz passive tags? Josh From: [email protected] [mailto:[email protected]] Sent: Thursday, November 20, 2003 7:24 AM To: [email protected] Cc: [email protected]; [email protected] Subject: Re: RFID tags ======================================= ============================================= The RFID tags (active tags) are subject to the RTTE Directive and the following standards for 13.56 MHz tags: 300 330-1 (General) 300 330-2 (Radio) 301 489-3 (EMC) Bob Heller 3M EMC Laboratory, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 ======================================================= Are RFID tags (e.g., access control badges) considered to be transmitters/receivers and thus subject to the RTTE Directive? These types of tags are powered by a received signal, may receive a coded signal, and they respond with a coded signal. They are obviously very low power devices and the transmit power is far below that of their interrogator. But the nagging fact remains that they are transponders. Richard Woods Sensormatic Electronics Tyco International This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
