Electronics and Telecommunications Research Institute

Korea Telecommunication Authority

Korea Telecom

Korea Telecommunication

Tae-Goo Choy

Sang-Seok Lee

Myung-Yung Jeong

Chang-Hwa Lee

Jung-Rae Park

Dong-Suk Jun

Tae-Hong Kim

Seung-Ho Ahn

Oh-Gone Chun

Sang-Ho Park

Suk-Jin Lee

Bon-Hee Koo

Meyng-Soo Kim

Ahn Seung-Ho

Hak-Seok Kim

Chun Oh-Gone

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

An improved multifiber optical connector is disclosed which concurrently transmits an optical signal and provides for optical signal transmission with a lower transmission loss. The connector includes an adapter including openings into which a plug is inserted, a pass through hole formed in a central portion of the multifiber optical connector, and engaging holes formed in portions of the multifiber optical connector, a plug, which engages the openings of the adapter, including a through hole, into which optical fibers are inserted, formed in a central portion of the plug, an engaging portion having an engaging jaw portion for connecting the plug to the adapter and formed at one end of the plug, a plug housing for receiving a body of the plug, a ferrule, which is disposed in one end of the plug, having a plurality of holes into which a core of the optical fibers are inserted to provide protection and alignment, an optical fiber alignment device inserted into the pass through hole of the adapter, for surrounding an outer portion of the ferrule disposed at one end of the plug inserted into the adapter and for aligning the optical fiber inserted into the ferrule, and an optical cable protector surrounding an outer portion of the optical cable connected for protecting against breakage of the optical cable.

Multifiber optical connector

The present invention relates to a dielectric ceramic composition for microwave which consists of BaO, Sm.sub.2 O.sub.3, TiO.sub.2 and PbO, and has a compositional formula of x(Ba.sub.1-.alpha., Pb.sub..alpha.)O-- ySm.sub.2 O.sub.3 -zTiO.sub.2, wherein 6 mol % .ltoreq.x.ltoreq.20 mol %, 6 mol %.ltoreq.y.ltoreq.20 mol %, 60 mol %.ltoreq.z.ltoreq.75 mol % and 0 mol % .ltoreq..alpha..ltoreq.0.2 mol %. Accordingly, since the dielectric ceramic composition for microwave according to the present invention has the dielectric constant more than 85, the temperature factor of the resonant frequency within .+-.5 ppm/.degree.C., and the quality factor more than 6000 in 1 GHz, it can be utilized in the filter for microwave, the dielectric for the resonator, the laminated ceramic capacitor, the dielectric for the filter for electromagnetic wave obstacle and the dielectric for capacitor. And also, since it is possible to reduce the problems to the volatilization of the plumbic oxide and the bismuth oxide, the dielectric ceramic composition for microwave according to the present invention can be made by a general manufacturing process and can reduce the use of the elements detrimental to the human body.

Dielectric ceramic composition for microwave

A multifiber optical connector for optical ribbon cable which must be essentially used in the optical line that requires a repeated connection and separation to transfer or to interrupt simultaneously optical signals with low loss by attaching to an end of the optical ribbon cable arranged in a line. In order to overcome a difficulty of production technique and to constitute a suitable net, the optical cable consists of a short circuit which must be connected for the maintenance of the optical path, in which the optical cable must be very precisely connected so as to minimize a loss. The multifiber optical connector for optical ribbon cable according to the present invention is comprised of arranging means comprising a ferrule to fix and arrange ends of both sides of multifiber optical cable for an exact connection, an arranging block for connecting section of both sides of the said ferrule to be coincided exactly and a leaf spring to act an elastic force upon the said ferrule; and connecting means comprising an adaptor, an optical cable protecting instrument and a plug in which the said arranging means are established and it connects them strongly, and which is capable of contributing to settle a period of an optical communication by early realization of a network of optical passivity in which a heart part of the optical connector, such as ferrule, arranging elements and connecting structure are embodied by using new materials and new structure and thus, commercial-viability, performance and assembling property are improved.

Multifiber optical connector for optical ribbon cable

A single core optical fiber connector is disclosed in which an optical signal transmitting line between optical fibers is maintained or short-circuited with a low power loss by utilizing a sectional contact of a single core optical fiber. An elastic deformation energy of a polymer material is utilized so as to achieve the sectional contact for minimizing the loss, and precisely machined alignment devices are utilized so as to reduce the misalignment between the optical fibers, thereby improving the assemblability and the economy. The optical fiber sections which are lightly ground on a grinding paper are contacted by using a precisely machined alignment device and by utilizing the elastic deformation energy of the elastic ferrule. This contact is maintained by a coupling between a specially designed plug and an adaptor, thereby forming a structure of an optical fiber connector and an alignment device. The ferrule, the alignment device and the coupling structure which are the critical factors for the optical fiber connector are provided in the form of a new material, a new technique and a new structure. Consequently, the economy, the performance and the assemblability are improved, thereby contributing to the early settlement of the fiber optics system.

Growing community of inventors

Daejeon, South Korea

Tae-Goo Choy