Electronics and Telecommunications Research Institute

Other

Korea Telecommunication Authority

Korea Telecom

Korea Telecommunication

Sang-Seok Lee

Tae-Goo Choy

Dong-Suk Jun

Chang-Hwa Lee

Jung-Rae Park

Tae-Hong Kim

Meyng-Soo Kim

Bon-Hee Koo

Dong-Young Kim

Tae-Goo Choi

Suk-Jin Lee

Oh-Gone Chun

A magnetostatic wave filter that includes a ferromagnetic substance stacked on one side of a dielectric substrate, one side of which is grounded, and the filter includes an input section having an input transfer line and an input energy transformer for causing the energy transformation between an electromagnetic wave and a magnetostatic wave, and an output section having an output energy transformer for causing the energy transformation between the electromagnetic wave and the magnetostatic wave and an output transfer line. The width of exciting lines in the input energy transformer and the output energy transformer varies in a longitudinal direction, the filter includes a shield film formed of a grounded conductive film having holes through which a magnetic thin film can pass between the input section and said output section, to prevent coupling of an electromagnetic wave.

Magnetostatic wave filter

A dielectric filter having a notch pattern includes a dielectric block, in which a ground face plated with conductive metal for all the rest portions excepting an upper face thereof and both side given portions of one side wall face connected to the upper face is formed and numerous patterns plated with the conductive metal are formed on the upper face as a non-conductive part, input electrode provided on one portion out of non-conductive portions and formed so that a signal from the outside may be inputted thereto, at least two resonators formed piercing through upper and lower faces of the dielectric block, a lower end part of which is short-circuited on a lower face as the ground face of the dielectric block, wherein two resonators are connected with each other through a pattern formed on the upper face of the dielectric block in order to resonate and wave-transfer a signal inputted through the input electrode, and output electrode provided in the rest one portion out of the non-conductive portions on one side wall face of the dielectric block, the output electrode being for outputting a signal resonated in each resonator to the outside.

Dielectric filter having notch pattern

A dielectric microwave filter includes a dielectric body, a trinity of first, second and third resonant slots, a pair of cavities for transmitting input/output signals, a pair of slits, and a trinity of first, second and third resonant holes. Each of the resonant slots (and an associated resonant hole in some embodiments) functions as a resonator having a quarter wavelength. Each of the slits modulates a coupling of electromagnetic fields among the resonant slots (and resonant holes if present). All surfaces of the dielectric microwave filter are completely covered with an electrically conducting material, except for front and top surfaces of the dielectric body. Since the resonators having a quarter wavelength may have reduced surface dimensions, the filter may accommodate associated surface input/output coupling cavities and also be more easily manufactured in a miniaturized structure. In addition, since the filter provides inductive coupling between resonators, it may better preserve a desired overall filter performance.

Dielectric microwave filter

A material for microwave band devices used by the general people and in industrial electronic apparatuses is disclosed. Particularly, a magnetic ceramic composition for use in microwave devices, a magnetic ceramics for use in microwave devices and a preparation method therefore are disclosed, in which the saturation magnetization can be easily controlled, and a low ferri-magnetic resonance half line width and an acceptable curie temperature are ensured. The magnetic ceramic composition for microwave devices includes yttrium oxide (Y.sub.2 O.sub.3), iron oxide (Fe.sub.2 O.sub.3), tin oxide (SnO.sub.2), aluminum oxide (Al.sub.2 O.sub.3) and a calcium supply source. The magnetic ceramics for the microwave devices are manufactured by carrying out a forming and a sintering after mixing: yttrium oxide, iron oxide, tin oxide, aluminum oxide and calcium carbonate (or calcium oxide) based on a formula shown below. It has a saturation magnetization of 100-1,800 G at the normal temperature, a temperature coefficient for the saturation magnetization of 0.2%/.degree.C., and a ferri-magnetic resonance half line width of less than 60 Oe, Y.sub.3-x Ca.sub.x/2 Sn.sub.x/2 Fe.sub.5-y Al.sub.y O.sub.12 where 0.1.ltoreq.x.ltoreq.1, and 0.1.ltoreq.y.ltoreq.1.5.

Magnetic ceramic composition for use in microwave devices, magnetic

A duplexer having dual coupled line characteristics is disclosed. With a small number of resonators and without using an external device such as a chip inductor or a chip capacitor, the signals of the receiving frequency can be improvingly damped. The diameters of the transmitting terminal dielectric filter resonators and the receiving terminal dielectric filter resonators are not same, but their diameters at an open terminal and at a short circuit terminal are made different from each other so as to differentiate a coupling amount at the short circuit terminal from that at the open terminal. Further, the transmitting terminal filter resonators and the receiving terminal dielectric filter resonator are provided in a form of grooves, and sizes of the grooves near the open terminal are made different from those of the grooves near the short circuit terminal so as to differentiate a coupling amount of the resonators at the short circuit terminal from those at the open terminal. The duplexer of the present invention is used in the transmission/receiving separate type filter of the mobile communication.

Duplexer having dual coupled line characteristics

The present invention relates to dielectric ceramic compositions for microwave applications consisting of BaO, PbO, Nd.sub.2 O.sub.3, CeO.sub.2, La.sub.2 O.sub.3 and TiO.sub.2 or consisting of compositions including these elements and having a composition formula (I).

Growing community of inventors

Daejeon, South Korea

Sang-Seok Lee