Samsung Electro-mechanics Co., Ltd.

Sungkyunkwan University

Qualcomm Incorporated

Hyundai Motor Company

Hyung Jin Choi

Se Bin Im

Tah Joon Park

Koon Shik Cho

Sang Hyun Min

Hyun Suk Lee

Jae Goon Aum

Joo Hyun Do

Jong Hyeon Park

Je Woo Kim

Jong Min Park

Je Hyuk Ryu

Jae Sik Seo

Kwang Mook Lee

Jin Yong Kang

Bon Young Koo

Kyung Mo Yang

Jung Eun Youm

U Sang Lee

Dae Sung Chang

Jung Tae Kim

Jung In Kim

Jung Soo Han

Jung Su Han

Shin Woo Kang

Kyung Doc Jang

Kyung Hoon Won

Je Woo c/o Qualcomm Incorporated Kim

A suspension fluid prepared by dispersing polyethylene oxide particles into a solvent including water and one or more types of compounds selected from the group consisting of ethylene glycol and propylene glycol, and a method for manufacturing the same. The phase-change suspension fluid can be a shear-thinning fluid showing a constant newtonian behavior in a low shear rate or low frequency region, but showing a non-newtonian behavior appearing as liquid-like suspension in a high shear rate or high frequency region due to viscosity decrease, and is capable of reversible phase changes by the vibration of a vehicle, and therefore, may provide effects of having advantages of a hydraulic bush in a low frequency region and also having advantages of a solid bush in a high frequency region.

Phase-change suspension fluid composition including polyethylene oxide particles and method for manufacturing the same

An embodiment of the present invention is a technique to process signals in a communication system. A channel impulse response (CIR) generator generates a time-domain windowed CIR from a received signal using a window function. A thresholder thresholds the time-domain windowed CIR. A compensator compensates window effect for the thresholded time-domain windowed CIR to provide an enhanced channel estimate in frequency domain.

Enhanced channel estimation for communication system receiver

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

A frequency synchronization apparatus includes: a correlating unit that obtains a first correlation value by correlating a known reference guard interval of an OFDM symbol and a reference copy interval corresponding to the reference guard interval, and obtains a second correlation value by correlating the estimate guard interval and an estimate copy interval corresponding to the estimate guard interval; a determining unit that compares the first and second correlation values to determine a first case where the first correlation value is larger by a pre-set magnification than the second correlation value, a second case where the second correlation value is larger by a pre-set magnification than the first correlation value, and a third case which is not the first case nor the second case; and a frequency offset estimating unit that estimates a frequency offset by using a correlation value corresponding to any one of the first to third.

Frequency synchronization apparatus and method in OFDM system

An apparatus and method for orthogonal frequency division multiplexing (OFDM) channel equalization are disclosed. The apparatus includes a compensation value setting unit setting a compensation value in the form of a diagonal matrix by use of a diagonal matrix of diagonal elements extracted from a channel matrix of an OFDM receiver, and a preset divergence suppression value, an initial estimation value calculation unit calculating an initial estimate value by use of a fast Fourier transform (FFT)-processed signal of the OFDM receiver and the compensation value, an equalization unit detecting a transmission signal to be processed by use of the compensation value, the channel matrix and the diagonal matrix, and a symbol decision unit determining a symbol for an adjacent signal of a transmission signal, which is to be processed among a plurality of signals output from the equalization unit, and providing the symbol-determined adjacent signal to the equalization unit.

Apparatus and method for OFDM channel equalization

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

A timing estimator of an OQPSK demodulator is provided. In the timing estimator, an A/D converter converts an analog reception signal into a digital reception signal. A differential circuit section delays the digital reception signal from the A/D converter by a preset time and obtains a phase difference between a conjugate complex number signal of the delayed digital reception signal and the digital reception signal to offset a frequency error contained in the digital reception signal. A correlation operation section performs a correlation operation between a reference symbol differentiated in the same way as a differentiation of the differential circuit section and the reception signal to obtain each correlation value. A coherent detector detects a coherent point on the basis of the correlation value from the correlation operation section.

Timing estimator in OQPSK demodulator

The invention relates to a symbol detector for detecting symbols received in a receive modem of short-range wireless personal area network of a ZigBee system (IEEE 802.15.4). An OQPSK short-range wireless communication system according to the invention acquires frequency offset in a received signal using a symbol contained in a preamble of a packet of the signal, multi-delay-differentiates the signal by a plurality of predetermined delay times, and complex-conjugates the acquired frequency offset to eliminate the frequency offset. Then, the OQPSK short-range wireless communication system according to the invention correlates the received signal with a PN sequence delay-differentiated through the same process to detect the symbols corresponding to the received signal.

Symbol detector based on frequency offset compensation in ZigBee system and symbol detecting method thereof

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Seoul, South Korea

Hyung Jin Choi