Samsung Electro-mechanics Co., Ltd.

Sungkyunkwan University

Jae Goon Aum

Hyun Suk Lee

Hyung Jin Choi

Tah Joon Park

Tae Kyung Lee

Chang Hyun Lim

Hyun Jun Kim

Won Jae Han

Sang Heon Han

Je Hyuk Ryu

Jeong Hoon Ryou

Chan Hee Park

Jung Eun Youm

Se Bin Im

Dong Hoe Kim

Jung Tae Kim

Hyun Min Hwang

Kyung Hoon Won

Jung Soo Han

A bulk acoustic resonator filter includes a series part including at least one series acoustic resonator electrically connected between a first and second radio frequency ports; and shunt acoustic resonators electrically connected to each other in series between a first node of the series part and a first ground port, wherein each of the shunt acoustic resonators comprises a resonance portion including a first electrode, a piezoelectric layer, and a second electrode; and an overlap region in which the first electrode, the piezoelectric layer, and the second electrode overlap, the overlap region has an aspect ratio equal to a ratio between a longest length of the overlap region in an extension direction of a longest side of the overlap region and a longest length of the overlap region in a direction perpendicular to the extension direction, and the aspect ratios of the shunt acoustic resonators include different aspect ratios.

Bulk acoustic resonator filter and bulk acoustic resonator package

A bulk-acoustic wave (BAVV) resonator is provided. The BAW includes a substrate, a first electrode disposed on the substrate, a piezoelectric layer disposed to cover at least a portion of the first electrode, and a second electrode disposed to cover at least a portion of the piezoelectric layer, wherein the piezoelectric layer includes an intermediate layer, a first layer disposed above the intermediate layer and a second layer disposed below the intermediate layer, the first layer and the second layer are symmetrical in relation to a plane through which a central line of the intermediate layer passes in a thickness direction, and a thickness of the intermediate layer is greater than a thickness of each of the first and second layers.

Bulk-acoustic wave resonator

A bulk acoustic resonator filter includes: a series bulk acoustic resonator electrically connected, in series, between first and second ports through which a radio frequency (RF) signal passes; a second shunt bulk acoustic resonator, electrically shunt connected between the series bulk acoustic resonator and a ground and having a resonance frequency lower than that of the series bulk acoustic resonator; and a first shunt bulk acoustic resonator electrically connected to the second shunt bulk acoustic resonator in series and having a resonance frequency higher than that of the second shunt bulk acoustic resonator. One or both of the series bulk acoustic resonator and the first shunt bulk acoustic resonator includes a first electrode disposed above a substrate; a piezoelectric layer disposed on the first electrode; a second electrode disposed on the piezoelectric layer; and a trench formed in an upper surface or above the second electrode and recessed downwardly.

Bulk acoustic resonator filter

There are provided a touchscreen device and a method of driving the same. The touchscreen device includes: a panel unit including a plurality of first electrodes extending in a first direction and a plurality of second electrodes extending in a second direction; and a control unit applying predetermined driving signals to at least one first electrode among first electrodes arranged sequentially from a first thereof and to at least one first electrode among first electrodes arranged sequentially from a last thereof, and detecting a change in capacitance from at least one of the first electrodes among electrodes disposed in a central portion, to thereby determine a touch.

Touchscreen device and method of driving the same

A sampling frequency offset estimation apparatus of an orthogonal frequency division multiplexing (OFDM) system includes a first differential operation unit performing complex conjugate multiplication of scattered pilots of complex symbols subjected to a fast Fourier transform (FFT) in an OFDM receiver, an interpolation unit repeating an operation of obtaining a median complex symbol between two consecutive symbols among complex symbols having first phase difference information from the first differential operation unit by a predetermined number, a second differential operation unit performing complex conjugate multiplication of two consecutive median complex symbols among median complex symbols from the interpolation unit, and a sampling frequency offset estimation unit estimating sampling frequency offset using complex symbols having second phase difference information from the second differential operation unit.

Sampling frequency offset estimation apparatus and method of OFDM system

Provided is an apparatus for estimating a delay spread of a multi-path fading channel in an Orthogonal Frequency Division Multiplexing (OFDM) system. The apparatus is applied to an OFDM receiver including a channel equalization unit compensating channel distortion by estimating channel distortion at pilot locations with respect to output signals of an FFT unit.

Apparatus and method for estimating delay spread of multi-path fading channel in OFDM system

Growing community of inventors

Gyunggi-do, South Korea

Jae Goon Aum