CA2214536A1 - Eas system with alternating on/off transmitter operation and loop antenna - Google Patents

Eas system with alternating on/off transmitter operation and loop antenna

Info

Publication number
CA2214536A1
CA2214536A1 CA002214536A CA2214536A CA2214536A1 CA 2214536 A1 CA2214536 A1 CA 2214536A1 CA 002214536 A CA002214536 A CA 002214536A CA 2214536 A CA2214536 A CA 2214536A CA 2214536 A1 CA2214536 A1 CA 2214536A1
Authority
CA
Canada
Prior art keywords
loops
eas system
alternating
loop antenna
antennas
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA002214536A
Other languages
French (fr)
Other versions
CA2214536C (en
Inventor
Frank Drucker
Sylvie R. Morin
Harry E. Watkins
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sensormatic Electronics Corp
Original Assignee
Sensormatic Electronics Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US07/967,846 external-priority patent/US5404147A/en
Application filed by Sensormatic Electronics Corp filed Critical Sensormatic Electronics Corp
Publication of CA2214536A1 publication Critical patent/CA2214536A1/en
Application granted granted Critical
Publication of CA2214536C publication Critical patent/CA2214536C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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  • Near-Field Transmission Systems (AREA)
  • Radar Systems Or Details Thereof (AREA)

Abstract

An EAS system in which a transmitter alternately drives first and second antennas with the same coded message signal in its entirety. The antennas, in turn, transmit first and second signals each containing the coded message signal into respective first and second partially overlapping parts of an interrogation zone. Also disclosed is an antenna structure comprised of a plurality of loops extending one after the other and successive ones of which are of opposite phase. One of the loops circumscribes an area which is smaller than each of the other loops to realize reduced coupling to adjacent structures.
CA002214536A 1992-10-28 1993-06-21 Eas system with alternating on/off transmitter operation and loop antenna Expired - Fee Related CA2214536C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US07/967,846 US5404147A (en) 1992-10-28 1992-10-28 EAS system loop antenna having three loops of different area
US07/967,846 1992-10-28
CA002098898A CA2098898C (en) 1992-10-28 1993-06-21 Eas system with alternating on/off transmitter operation and loop antenna

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
CA002098898A Division CA2098898C (en) 1992-10-28 1993-06-21 Eas system with alternating on/off transmitter operation and loop antenna

Publications (2)

Publication Number Publication Date
CA2214536A1 true CA2214536A1 (en) 1994-04-29
CA2214536C CA2214536C (en) 2001-04-03

Family

ID=25676304

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002214536A Expired - Fee Related CA2214536C (en) 1992-10-28 1993-06-21 Eas system with alternating on/off transmitter operation and loop antenna

Country Status (1)

Country Link
CA (1) CA2214536C (en)

Also Published As

Publication number Publication date
CA2214536C (en) 2001-04-03

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