Electronics and Telecommunications Research Institute

Korea Telecom

Eg Co., Ltd.

Jin Woo Hahn

Sang Seok Lee

Tae Goo Choy

Dong Suk Jun

Dong Young Kim

Hong Yeol Lee

Yark Yeon Kim

Duk Jun Kim

Gee Pyeong Han

Dong-Young Kim

Kyoung Suk Ko

A dictionary coupler using a non-radiative dielectric waveguide is disclosed. Particularly, a millimeter wave band non-radiative dielectric waveguide directional coupler using a multiple-hole structure in which two parallel NRD waveguides located between upper and lower conductive plates and a conductive plate having a multiple-hole structure is inserted between two NRD waveguides to couple electric and magnetic waves of an electric field component or a magnetic field component is provided.

Directional coupler using non-radiative dielectric waveguide

A S/N enhancer using the magnetostatic wave signal. The S/N enhancer comprises a balun coupler for dividing an input signal into a first and second signals having the same power, the second signal having the phase difference of 180 degree with respect to the first signal; a saturation magnetostatic wave filter for receiving the first signal output from the balun coupler, converting that into a magnetostatic wave signal, and oppositely converting the magnetostatic wave signal, wherein the power of the magnetostatic wave signal is saturated if the first signal has the power of equal to and more than that of a noise signal; a delay line having the linearity to transmit the second signal output from the balun coupler; and a power synthesizer for synthesizing the respective signals output from the saturation magnetostatic wave filter and the delay line.

S/N enhancer

The present research provides a high-density magnetic ceramic composition for microwave application and a preparation method thereof. The magnetic ceramic composition of this research includes Yttrium iron garnet (YIG, YFeO) as its basic element and a little amount of additional element, silicon oxide (SiO), which is expressed as: YFeO+x SiO(0.05&#x2266;x&#x2266;5 mol %). The magnetic ceramic composition is prepared by measuring proper amounts of ferric oxide (FeO), yttrium oxide (YO) and SiO, mixing them, calcining the mixture, and molding and sintering them. Since the magnetic ceramic composition of the present research has very little magnetic loss, it can be used in components for communication in a microwave band, usefully.

YIG magnetic ceramic composition for microwave application and preparation method thereof

A S/N enhancer using the magnetostatic wave signal. The S/N enhancer comprises a balun coupler for dividing an input signal into a first and second signals having the same power, the second signal having the phase difference of 180 degree with respect to the first signal; a saturation magnetostatic wave filter for receiving the first signal output from said balun coupler, converting that into a magnetostatic wave signal, and oppositely converting the magnetostatic wave signal, wherein the power of the magnetostatic wave signal is saturated if the first signal has the power of equal to and more than that of a noise signal; a linear magnetostatic wave filter for receiving the second signal from said balun coupler, converting that into a magnetostatic wave signal, and oppositely converting the magnetostatic wave signal, wherein the received second signal is converted into the magnetostatic wave signal having an energy linear to the power of the input signal; and a power synthesizer for synthesizing the respective signals output from said saturation magnetostatic wave filter and said linear magnetostatic wave filter.

MgAl2O4-system dielectric ceramic composition and method for fabricating dielectric ceramic using the same

A dielectric ceramic composition for a microwave device including MgTiO.sub.3 and CaTiO.sub.3 as a main component and a Li.sub.2 CO.sub.3 as a sub-component is provided. The composition being expressed as follows: (94MgTiO.sub.3 -6CaTiO.sub.3)+xLi.sub.2 CO.sub.3 (mol %), where 0.2.ltoreq.x.ltoreq.0.8 (mol %). Therefore, it is capable of increasing a quality factor and decreasing a sintering temperature by adding a new component and effectively reproducing the above-described dielectric characteristic.

Dielectric ceramic composition of microwave MGTIO.sub.3 CATIO.sub.3

A microwave dielectric ceramic composition is fabricated by adding one selected from a material containing Ba and a material containing Sr or a mixture of a material containing Ba and a material containing Sr to a composition formed of 25.about.43 wt % of TiO.sub.2, 39-57 wt % of ZrO.sub.2, and 7-28 wt % of SnO.sub.2 as an additive, wherein the additive is added by 0.2.about.8.0 wt % based on the total amount of the composition, and is capable of implementing a high dielectric constant and quality factor by sintering at a temperature of 1250.about.1400.degree. C.

Growing community of inventors

Daejon-Shi, South Korea

Jin Woo Hahn