Electronics and Telecommunications Research Institute

In Bok Yom

Man Seok Uhm

Seong Mo Moon

Chang Soo Kwak

Hong Yeol Lee

Changsoo Kwak

Youn Sub Noh

Dong Hwan Shin

In Kwon Ju

So Hyeun Yun

Jin Cheol Jeong

So-hyeun Yun

Hongyeol Lee

Ho Jin Lee

Seong-Pal Lee

Byoung Hak Kim

Dong Pil Chang

Jun Han Lim

Moon-Que Lee

Jang Sup Choi

Jang-sup Choi

Moon Que Lee

Keun Kwan Ryu

Provided is a FET resistive frequency mixing device having improved RF-LO and IF-LO isolations. The frequency mixing device includes: a field effect transistor (FET), a local oscillation matching circuit connected to a gate of the FET to transfer a local oscillation signal to the gate of the FET, a gate biasing circuit connected to the gate of the FET, a radio frequency (RF) matching circuit having a first terminal connected to a drain side of the FET and a second terminal serving as a RF terminal to receive or output a RF signal, an intermediate frequency (IF) matching circuit having a first terminal connected to the drain side of the FET and a second terminal serving as an IF terminal to receive or output an IF signal, and a series resonance circuit providing a path from the drain of the FET to ground for the local oscillation signal.

Frequency mixing device

Disclosed is a multimode microwave filter including a resonator in which a cavity is formed to generate a resonant mode and a plurality of irises formed on a side surface of the resonator, in which the cavity of the resonator has a rhombus-shaped cross section.

Multimode microwave filter

Provided is a microwave filter system having a feedback structure. The microwave filter system may include an input hybrid coupler configured to output first output signals having a phase difference with respect to an input signal; filters disposed to be in parallel with an output end of the input hybrid coupler, and configured to filter the first output signals; and an output hybrid coupler configured to output second output signals having a phase difference with respect to each of signals filtered through the filters. An output signal of the output hybrid coupler is applied to an input end of the input hybrid coupler along a feedback path.

Microwave filter system including feedback structure

A tunable filter device that changes a central frequency and a bandwidth is provided. The tunable filter device may include a body forming a cavity together with a cover, a resonator attached to or integrally formed on a lower surface of the cavity, a frequency-tuning element including a head and a shaft, the shaft passed through the cover and inserted in the resonator, and a cam disposed on the head to contact the head, wherein an insertion length of the shaft is controlled by the cam.

Variable high frequency filter device and assembly

The present invention relates to a dual reflector antenna with a hybrid subreflector, and more particularly, to a dual reflector antenna with a subreflector having a structure in which an ellipse and a hyperbola are combined. An exemplary embodiment of the present invention provides a dual reflector antenna including: a main reflector; and a hybrid subreflector which faces the main reflector and has a first structure and a second structure which are combined therein.

Dual reflector antenna with hybrid subreflector

Disclosed is a low phase shift voltage variable attenuator. The low phase shift voltage variable attenuator may include: a first directional coupler including a first input terminal in which a signal is input, a first isolation terminal connected to a ground power source through a termination resistor, a first coupling terminal, and a first through terminal; a second directional coupler including a second input terminal through which an attenuated signal, which is the attenuated input input signal, is output, a second isolation terminal connected to a ground power source through a termination resistor, a second coupling terminal, and a second through terminal; and a signal attenuating unit connected to the first coupling terminal, the first through terminal, the second coupling terminal, and the second through terminal, and configured to attenuate a signal transmitted through the first directional coupler to transmit the attenuated signal to the second directional coupler.

Low phase shift voltage variable attenuator

Provided is an antenna apparatus which employs a small number of antenna devices and is intended to obtain a desired pattern without adjusting amplitude level and phase of each antenna device. The antenna apparatus includes a first ridge horn antenna, and a second ridge horn antenna spaced apart from the first ridge horn antenna by a determined distance. Here, a multi-beam pattern is generated using a third-order mode beam pattern of a synthetic beam obtained by synthesizing beams respectively radiated from the first and second ridge horn antennas. Accordingly, the antenna apparatus can be simplified, and a desired multi-beam pattern can be obtained without adjusting signal level and phase of each antenna device. Also, by employing the ridge horn antennas as array devices, the antenna apparatus can be used in a wide frequency band.

Antenna apparatus

A butler matrix includes at least one input coupler that is positioned at an input end of the butler matrix, receives an input signal, and divides and outputs it to a plurality of paths, and at least one output coupler that receives a signal from the input coupler and divides the signal into a plurality of paths to output it as an output signal. A separation coupler is formed in an intersecting path including an intersecting section at which transmission paths intersect among a plurality of paths through which a signal is transmitted to separate signals transmitted through different transmission paths. Further, a compensation coupler is formed in a path excluding the intersecting path to compensate a phase difference.

Butler matrix

A multiport amplifier modulates a reference quadrature phase shift keying (QPSK) signal using an input RF signal to an input hybrid network, generates a plurality of binary phase shift keying (BPSK) signals by demodulating RF signals that are amplified by a plurality of power amplifiers, detects an amplitude error and a phase error of two corresponding amplified RF signals by comparing a QPSK signal that is generated by coupling two RF signals having a phase difference of 90&#xb0; among the plurality of BPSK signals with a reference QPSK signal, and compensates the detected amplitude error and phase error.

Apparatus for calibrating amplitude and phase errors, multiport amplifier including the same, and method of amplifying the multiport amplifier

The present invention relates to an antenna system mounted on a mobile vehicle. In the present invention, a power distributor and a part of a high-frequency module that includes a frequency converter are placed in an external fixed unit that is placed outside a radome. In addition, an active cooler/cooling fin, a heater, and an air circulation fan are placed at an internal bottom plane of the antenna system, and a cooling fin and cooling fan are placed at an external bottom plane of the antenna system.

Antenna system for mobile vehicles

Provided is a line filter. The line filter includes a plurality of dielectric layers stacked one another, a plurality of line resonator each comprising transmission lines on at least two of the dielectric layers, and a tuning unit adjusting a binding amount and resonance frequency of the line resonators. Since the line filter includes at least one line resonator on at least two stacked dielectric layers, the integration can be easily realized. Further, since the line filter can be adjusted even after the line filter is manufacture, the line filter has an excellent frequency property. Since the line filter is realized on the plurality of the dielectric layers, the frequency band can be widened.

Line filter formed on dielectric layers

An ultra wideband hermetically sealed surface mount package for a microwave monolithic integrated circuit (MMIC) is provided including: an integrated circuit; a package body being mounted with the integrated circuit and comprising a plurality of first dielectrics formed in a multilayer, a first line unit mounted to a circuit substrate and is electrically connected with an external circuit, a second line unit upwardly extended from the first line unit and is electrically connected with the first line unit, a third line unit extended to the right angle from the second line unit and is electrically connected with the second line unit, and a bonding unit that electrically connects the third line unit and the mounted integrated circuit; and a package cover being formed on the package body to seal the integrated circuit and comprising a plurality of second dielectrics formed in a multilayer.

Ultra wideband hermetically sealed surface mount technology for microwave monolithic integrated circuit package

Provided is a marchand balun device. The marchand balun device includes: a first line connected between a balanced terminal and a ground terminal; a second line disposed horizontally parallel to the first line and forming a parallel capacitance jointly with the first line; and a coupled line disposed vertically parallel to the first and second lines and forming a vertical capacitance jointly with one of the first and second lines.

Marchand balun device for forming parallel and vertical capacitance

A high speed flip-flop circuit and a configuration method thereof are provided. A small number of transistors may be used to configure a flip-flop circuit, so that the flip-flop circuit may be operated at a high-speed. Additionally, an area occupied by the flip-flop circuit may be reduced, and power consumption may be reduced. Accordingly, the flip-flop circuit may be integrated together with a microwave frequency integrated circuit using a Gallium Arsenide (GaAs) compound semiconductor process.

High speed flip-flop circuit and configuration method thereof

A multi-function MMIC operated by a switch using an amplifier is disclosed. A switch may be configured by connecting an input or an output of a plurality of amplifiers, and an insertion loss may be reduced by selecting a transmission mode or a reception mode of an MMIC using the switch. A noise characteristic, a power characteristic, and a gain characteristic may also be improved.

Growing community of inventors

Daejeon, South Korea

In Bok Yom