Electronics and Telecommunications Research Institute

Korea Advanced Institute of Science and Technology

Samsung Electronics Co., Ltd.

Chul-Soon Park

In-Sang Song

Jeon-Wook Yang

Eung-Gie Oh

Inn-Yeal Oh

Chae-Jun Lee

Hong-Yi Kim

Dong-Hyun Lee

Young-hwan Kim

Kwang-Eui Pyun

Hyung-Moo Park

Sung-Tae Choi

Duck-Dong Hwang

Joong-Ho Lee

Won-Suk Choi

Sin-Chong Park

Jung-Han Choi

Jin-Hee Lee

Min-Kyu Song

Dong-Goo Kim

Hyung-Jin Yoon

Gyeong-Lyong Park

Sang-Soo Choi

Tae-Hwan Jang

Hyung-Jun Yoo

Hyung-Sup Youn

Dong-Min Kang

Ki-Chan Eun

A differential Colpitts voltage-controlled oscillator according to example embodiments includes a feedback circuit constituting a Colpitts oscillator structure, a negative resistance circuit including a first negative resistance transistor and a second negative resistance transistor cross-coupled to each other and connected to the feedback circuit, a resonance circuit including a first inductor and a variable capacitor connected to both ends of the first inductor to generate differential output signals base on outputs of the feedback circuit, and a phase noise reduction circuit coupled to the feedback circuit to remove phase noise.

Differential Colpitts voltage-controlled oscillator

A series-fed E-shaped patch antenna array has co-polarized parasitic patches to improve aperture efficiency. Each of microstrip parasitic patches is inserted between a plurality of microstrip E-shaped patch antennas. The parasitic patches are co-polarized with the E-shaped patch antennas so that the current flows in the parasitic patches and the E-shaped patch antennas have the same polarity. Additional radiation from the co-polarized microstrip parasitic patches significantly improves gain flatness, gain and aperture efficiency due to offset resonance frequency.

Series-fed E-shaped patch antenna array with co-polarized parasitic patches

A wireless communication system provides an antenna apparatus for the wireless communication system. The antenna apparatus includes a base, a plurality of Yagi-Uda antenna modules disposed in a specific arrangement, a plurality of floating metal modules correspondingly installed in upper portions of the Yagi-Uda antenna modules and selectively connected to a corresponding Yagi-Uda module among the plurality of Yagi-Uda antenna modules, a switching element for selectively switching the floating metal module and the Yagi-Uda antenna module, and a controller for controlling the Yagi-Uda antenna module to comprise a directivity in a desired direction by selectively switching the switching element.

Method and apparatus for beamforming

An antenna device in a wireless communication includes antenna wires of four sides which include three feeding points and have a loop structure and four main switches which are located among the antenna wires of the four sides, wherein the antenna device operates as a loop antenna when the antenna wires of the four sides are connected according to operations of the main switches and wherein the antenna device operates as dipole antennas when the antenna wires of the four sides are disconnected according to operations of the main switches.

Antenna structure in wireless communication system and operation method thereof

Disclosed are a beamformer and a beamforming method. The beamformer includes a plurality of dividers, each of which divides an input signal along a plurality of paths, an input switch which selects one of the dividers such that the input signal is input to the selected divider, a phase shifter which shifts phases of respective output signals from the divider, and an output switch which transmits the output signals from the phase shifter to an antenna.

Beamformer and beamforming method

This invention provides infrared sensing photodetector and a method therefor which provides a structure for effectively absorbing a light incident in a normal direction on a substrate, and a method compatible with existing processes for making integrated circuitry. An infrared sensing photodetector includes a compound semiconductor substrate of a first conductivity type, superlattice areas having implanted impurity ions of a second conductivity type opposite to the compound semiconductor substrate, each being spaced a predetermined distance each other in a selected region of the semiconductor substrate, a first collector area and a first emitter area which are formed in both end portions positioned perpendicular relative to the doped superlattice areas, a first collector electrode and a first emitter electrode formed on the first collector area and the first emitter area, respectively, a second collector area and a second emitter area which are spaced a predetermined distance in a horizontal direction on the doped superlattice area, and a second collector electrode and a second emitter electrode formed on the second collector area and the second emitter area, respectively.

Infrared photodetector with doping superlattice structure

A method for making a T-shaped gate of a field effect transistor is disclosed. The method includes the steps of sequentially depositing first and second photoresist layers on a semiconductor substrate and performing an exposure using electron beams having different energy, one of the electron beams having a first energy to lightly expose only the second photoresist layer and the other of the electron beams having a second energy to lightly expose all of the first and second layers. The invention reduces gate resistance and parasitic capacitance of the T-shaped gate.

Method for making T-gate of field effect transistor

A production method for ion-implanted MESFET having self-aligned LDD structure and T-type gate, that the reverse mesa portion is formed at a predetermined part of the channel region which the source and drain regions are formed at both side by using caps layer, the ion is injected between the source and drain regions and the channel region as the small energy and low concentration by using the reverse mesa as the mask, the source and drain regions of the low concentration is formed so that drain part has more broadly than source part, and the gate electrode and the source and drain regions of the low concentration are not contacted at the formed groove which is removed the surface of the reverse mesa portion or the reverse mesa portion.

Production method for ion-implanted MESFET having self-aligned lightly

A flat display device has a plurality of pixels and a plurality of micro light valves which correspond to each of the pixels thereof, and has a plurality of selection lines and data lines disposed in a matrix the micro light valves each comprise a data electrode to be connected with each of the data lines through a via, a selection electrode to be connected with each of the selection lines, a common electrode formed between the selection and data electrodes, a frame, and a shifting element capable of being moved in the frame by driving signals to be applied to the data and selection electrodes, so as to pass or shut off a light beam. A first driving means is connected to the respective selection lines, for supplying a predetermined selection signal for said light valves; and a second driving means is connected to the respective data lines, for supplying a predetermined data signal for said light valve.

Flat display device and method for manufacturing the same

Growing community of inventors

Daejeon, South Korea

Chul-Soon Park