EP 0371562 A1 19900606 - Loop antenna device.
Title (en)
Loop antenna device.
Title (de)
Ringantennenvorrichtung.
Title (fr)
Dispositif d'antenne boucle.
Publication
Application
Priority
NL 8802914 A 19881128
Abstract (en)
A loop antenna device (10) for a two-frequency electromagnetic detection system is disclosed. The device serves to generate an electromagnetic interrogation field for detecting responders comprised by the system. The device comprises a closed loop built up of four adjoining sections having substantially equal impedances, the junction between each pair of adjoining sections together (11, 12, 13, 14) with the junction between the complementary pair of adjoining sections forming a connection port so that two connection ports (31, 33, 32, 34) are provided which in operation are available for two independent signals having different frequencies.
IPC 1-7
IPC 8 full level
H01Q 5/00 (2006.01); H01Q 5/35 (2015.01); H01Q 5/50 (2015.01); H01Q 7/00 (2006.01)
CPC (source: EP)
H01Q 1/2216 (2013.01); H01Q 5/35 (2013.01); H01Q 5/50 (2015.01); H01Q 7/00 (2013.01)
Citation (search report)
- [Y] EP 0186483 A2 19860702 - SENELCO LTD [GB]
- [X] US 4012742 A 19770315 - DEMPSEY RICHARD C
- [X] DE 2921225 A1 19801204 - BOTHFELD HELGE
- [A] GB 2071424 A 19810916 - PIONEER ELECTRONIC CORP
- [A] US 4260990 A 19810407 - LICHTBLAU GEORGE J
- [A] US 3902177 A 19750826 - MORI KENZO, et al
- [Y] PATENT ABSTRACTS OF JAPAN, vol. 1, no. 72, page 696E77, 13th juli 1977; & JP-A-52 008 754 (DENKI KOGYO) 22-01-1977.
Designated contracting state (EPC)
AT BE DE FR GB NL
DOCDB simple family (publication)
EP 0371562 A1 19900606; EP 0371562 B1 19950208; AT E118291 T1 19950215; DE 68921048 D1 19950323; DE 68921048 T2 19950601; NL 8802914 A 19900618
DOCDB simple family (application)
EP 89203011 A 19891127; AT 89203011 T 19891127; DE 68921048 T 19891127; NL 8802914 A 19881128