Samsung Electronics Co., Ltd.

Postech Academy-industry Foundation

Lg Electronics Inc.

Electronics and Telecommunications Research Institute

Eun Ae Lee

Joon Ho Cho

Minuk Kim

Jubum Kim

Ki Jun Kim

Hyun Kyu Chung

Kijun Lee

Myungkyu Lee

Sunghye Cho

Kyomin Sohn

Juyul Lee

Chan-Hong Kim

Myung Don Kim

Yeo-Hun Yun

Yeo Hun Yun

Jeong Ho Yeo

Min Uk Kim

Jinup Kim

Ju Bum Kim

A memory device may include counters respectively corresponding to rows and each configured to count a number of accesses to a corresponding row, a refresh control circuit, a queue, and first flags respectively corresponding to the rows. The refresh control circuit may change a second flag set in a refresh period every refresh period, and determine whether to put an incoming row address into the queue based on a count value of a counter corresponding to a target row indicated by the incoming row address among the counters, a first flag value of a first flag corresponding to the target row among the first flags, and a second flag value of the second flag set in a current refresh period.

Memory device and refresh method thereof

Disclosed are an apparatus and a method for estimating a parameter of a multi path signal. The apparatus for estimating a parameter of a multi path signal includes: a plurality of pre-processing units configured to pre-process respective reception signals received through a plurality of antennas; a plurality of parameter converting units configured to approximate a parameter set of the respective pre-processed reception signals to have a sparse characteristic in a Doppler frequency and angle of arrival domain; and a parameter estimating unit configured to estimate an angle of arrival for a plurality of reception signals in each frequency region of the Doppler frequency and angle of arrival domain.

Apparatus and method for estimating parameter of multi path signal

A transmission and reception method and apparatus for reducing a PAPR in an orthogonal frequency division multiplexing (OFDM) system are provided. A transmission method includes performing constellation rotation with respect to L input data symbols, performing L-point DFT spreading and circular extension on the constellation-rotated L data symbols to be K symbols, performing frequency domain (FD) windowing processing by multiplying the K circular-extended data symbols by a circular filter coefficient, and transmitting the processed data symbols.

Transmission and reception method and apparatus for reducing peak to average power ratio in orthogonal frequency division multiplexing system

A method of transmitting a signal based on multi-stream CPDMA may include: allocating a plurality of data symbols to each of a plurality of data streams based on a frequency hopping pattern; applying a DFT function and a M-times repetition function to the data symbol allocated to the each of the plurality of data streams; applying a spectral weighting vector to the each of the plurality of data streams applying the DFT function and the M-times repetition function; and generating the signal based on the multi-stream CPDMA by performing an IDFT function and a cyclic prefix adding procedure with respect to the plurality of data streams to which the spectral weighting vector is applied, in which the spectral weighting vector is a vector for determining a frequency band in which the each of the plurality of data streams is used.

Method and apparatus of transmitting data based on frequency hopping

Growing community of inventors

Daegu, South Korea

Eun Ae Lee