EP 0439337 A3 19911106 - BROAD-BAND WAVE ABSORBER
Title (en)
BROAD-BAND WAVE ABSORBER
Publication
Application
Priority
- JP 1579890 A 19900125
- JP 2381890 A 19900202
- JP 15069090 A 19900608
- JP 16240390 A 19900620
Abstract (en)
[origin: EP0439337A2] The present invention relates to a broad-band wave absorber wherein plates (3) formed of a ferrite magnetic material are placed at an optimal spacing and are aligned in a lattice form in longitudinal and lateral directions on a conductive plate (2). A magnetic substance of a specific thickness tm is formed into cylindrical blocks of a height d (where d >/= tm) wherein an end surface thereof is polygonal, and the cylindrical blocks are provided with a radio-wave reflecting surface aligned in such a manner that this surface is perpendicular to the axial direction of the blocks, and the end surface of the blocks is approximately perpendicular to a direction from which radio waves are incident. The ferrite magnetic substance could also be formed into rectangular prisms of thickness 2tm, height d, and length in the longitudinal direction thereof L, with the prisms aligned at a spacing b on a radio-wave reflecting surface, the direction of the height dimension of the prisms being approximately parallel to a radio-wave incidence direction, and the surfaces thereof of the dimensions 2tm and L being perpendicular to the radio-wave incidence direction, forming a plane parallel to a magnetic field direction of incident radio waves and the dimension L, wherein the following relationships hold: L >/= d >/= 2tm 20tm >/= b >/= 2tm <IMAGE>
IPC 1-7
IPC 8 full level
H01Q 17/00 (2006.01)
CPC (source: EP)
H01Q 17/008 (2013.01)
Citation (search report)
- [X] US 4701761 A 19871020 - AFFINITO JOHN [US]
- [A] GB 776158 A 19570605 - WERNER GENEST GES FUR ISOLIERU
- [A] GB 1170420 A 19691112 - ELTRO GMBH [DE]
- [A] IEEE TRANSACTIONS ON BROADCASTING. vol. 25, no. 4, December 1979, NEW YORK US pages 143 - 146; TAKIZAWA: 'REDUCTION OF GHOST SIGNAL BY USE OF MAGNETIC ABSORBING MATERIAL ON WALLS '
Designated contracting state (EPC)
DE FR GB SE
DOCDB simple family (publication)
EP 0439337 A2 19910731; EP 0439337 A3 19911106; EP 0439337 B1 19950405; DE 69108577 D1 19950511; DE 69108577 T2 19960111; KR 0130755 B1 19980414
DOCDB simple family (application)
EP 91300505 A 19910123; DE 69108577 T 19910123; KR 910001084 A 19910123