Patents by Inventor In Kyeong Choi
In Kyeong Choi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 8121208Abstract: The present invention relates to a multi-input multi-output (MIMO) system for enhancing transmission performance. The MIMO system uses space-time encoding and transmit antenna selection methods, and includes a transmitter (100) and a receiver (200). The transmitter (100) includes N transmit antennas (130-1, 130-4) that are more than M transmit antennas (130-1, 130-3) used for transmitting a signal to space channel, selects the M transmit antennas (130-1, 130-3) among the N transmit antennas (130-3 130-4), and transmits symbol by space-time encoding the symbol. The receiver (200) includes M receive antenna (120-1, 210-2) for receiving a signal from the space channel, detects an information symbol by using the signal received through the receive antenna (210-1, 210-2), generates transmit antenna selection information for selecting M transmit antennas (130-1, 130-3) among transmit antennas (i30-1, . . . 7130-4) with reference to a channel estimate, and returns the information to the transmitter.Type: GrantFiled: August 10, 2005Date of Patent: February 21, 2012Assignees: Electronics and Telecommunications Research Institute, Industry-Academic Cooperation Foundation, Yonsei UniversityInventors: Young-Seog Song, Seong-Rag Kim, In-Kyeong Choi, Choong-Il Yeh, Seung-Joon Lee, Hyoung-Soo Lim, Kwang-Jae Lim, Yu-Ro Lee, Jong-Ee Oh, Dong-Seung Kwon, Seung-Ku Hwang, Chung-Yong Lee, Myeong-Cheol Shin
-
Patent number: 8107514Abstract: A receiver according to an exemplary embodiment of the present invention receives a transmitted signal, converts the signal to a predetermined symbol, and estimates channel information including a channel gain of a channel of the transmitted signal. In addition, the receiver generates an intermediate processing value for decoding the signal based on the estimated channel information and the symbol, and normalizes the intermediate processing value to the channel gain to generate a reference value. The generated reference value is used for a soft-decision value for decoding the signal. In addition, when the signal is decoded by using a hard-decision value, a constellation point value that is closest to the reference values is generated and set as the hard-decision value.Type: GrantFiled: December 9, 2005Date of Patent: January 31, 2012Assignees: Samsung Electronics Co., Ltd., Electronics and Telecommunications Research Institute, KT Corporation, SK Telecom Co., Ltd, KTFreetel Co., Ltd., Hanaro Telecom, Inc.Inventors: Seung-Joon Lee, Dong-Seung Kwon, Seong-Rag Kim, In-Kyeong Choi
-
Patent number: 8077792Abstract: In a method for allocating transmission power in a communication system including multiple antennas, a plurality of subcarriers are grouped by a plurality of groups, and each group includes at least one subcarrier. A transmission power weight and an antenna transmission vector are calculated for each group by using channel information, a transmission power for each group of each antenna is calculated by using the transmission power weight and the antenna transmission vector for each group, and transmission signals are transmitted through the multiple antennas after determining which signals need to be transmitted from the multiple antennas by using the transmission power.Type: GrantFiled: December 11, 2006Date of Patent: December 13, 2011Assignees: Samsung Electronics Co., Ltd, Electronics and Telecommunications Research Institute, KT Corporation, SK Telecom Co., Ltd, Hanaro Telecom, Inc.Inventors: Yu-Ro Lee, In-Kyeong Choi, Dong-Seung Kwon
-
Publication number: 20110206156Abstract: A method for transmitting, by a transmitting terminal, data to a receiving terminal in a wireless communication system includes: generating a first detection field including symbols modulated by using a BPSK data tone; generating a second detection field including symbols modulated such that an even numbered subcarrier and an odd numbered subcarrier have a phase difference of 90 degrees; generating a data packet including the first detection field, the second detection field, and the data; and transmitting the data packet.Type: ApplicationFiled: February 23, 2011Publication date: August 25, 2011Applicant: Electronics and Telecommunications Research InstituteInventors: Il-Gu LEE, In-Kyeong CHOI, Yu-Ro LEE, Jong-Ee OH, Eun-Young CHOI, Sok-Kyu LEE
-
Publication number: 20110122782Abstract: The present invention relates to a method for random beam-forming based on a codebook. The method includes generating a first random variable corresponding to a Gaussian distribution; generating a second random variable corresponding to a uniform distribution; generating a plurality of beam elements by using the first variable, the second variable, spatial correlation between channels, and indexes of transmitting antennas; and forming a beam by using the plurality of beam elements.Type: ApplicationFiled: August 29, 2008Publication date: May 26, 2011Applicants: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTIT, SAMSUNG ELECTRONICS CO., LTD.Inventors: In-Kyeong Choi, Dong Seung Kwon, Ji Won Kang, Chung Yong Lee
-
Publication number: 20110096738Abstract: A MU-MIMO method of an access point in a WLAN using multi-channels and having at least one station includes: receiving index information indicating a precoding vector for a beam selected by the station and channel quality information thereof for each one of the multi-channels; generating first channel capacity information of channel combination groups using the channel quality information wherein the channel combination groups are grouped according to a predetermined channel bandwidth of the multi-channels; and allocating resources to the station from a channel combination selected from the channel combination groups according to the first channel capacity information using the index information and the channel quality information, wherein the access point and the station previously store precoding vector information for a plurality of beams for the MU-MIMO.Type: ApplicationFiled: October 22, 2010Publication date: April 28, 2011Applicant: Electronics and Telecommunications Research InstituteInventor: In-Kyeong CHOI
-
Patent number: 7920646Abstract: The present invention relates to a system for selecting a switched beam for supplying a maximum received power to a subscriber station, and a method thereof. The number of switched beams used by a base station is limited, and a weight value vector for forming the switched beam is predefined. The subscriber station uses a pilot signal for discerning transmitting antennas to estimate channel values for the respective transmitting antennas, and uses the channel values and the predefined weight value vectors to determine a switched beam for supplying a maximum signal-to-noise ratio (SNR). The subscriber station notifies the base station of an identifier of a selected beam by using a feedback channel, and the base station uses the switched beam to transmit traffic data.Type: GrantFiled: December 21, 2005Date of Patent: April 5, 2011Assignee: Samsung Electronics Co., LtdInventors: Choong-Il Yeh, Young-Seog Song, In-Kyeong Choi, Dong-Seung Kwon
-
Patent number: 7903753Abstract: A space-time code used for a transmitter to transmit a plurality of data symbols to a receiver in a MIMO system, the space-time code including a code word matrix for transmitting an amount of data symbols corresponding to a product of the number of transmit antennas and a spatial multiplexing rate during one block period, wherein a row index indicates combined signals transmitted through different transmit antennas and a column index indicates time slots that correspond to the number of transmit antennas, and wherein the number of data symbols allocated to each transmit antenna in a code block corresponds to the spatial multiplexing rate, and the data symbols are combined by different combining coefficients for each transmit antenna at every time slot, and simultaneously transmitted through different transmit antennas, and each transmit antenna transmits a different set of data symbols at every time slot.Type: GrantFiled: February 28, 2005Date of Patent: March 8, 2011Assignee: Electronics and Telecommunications Research InstituteInventors: Seung-Joon Lee, Choong-Il Yeh, Dong-Seung Kwon, Seung-Ku Hwang, Hyoung-Soo Lim, In-Kyeong Choi, Jong-Ee Oh, Kwang-Jae Lim, Seong-Rag Kim, Young-Seog Song, Yu-Ro Lee, Seong-Keun Oh, Moon-Il Lee
-
Patent number: 7889805Abstract: A mobile station transmitting and receiving method and a corresponding mobile station transmitter and receiver of a smart antenna system for forming uplink eigenbeams of the OFDM/TDD (orthogonal frequency division multiplex/time division duplex), wherein OFDM symbols are received from a base station through a downlink via multiple antennas (250) and an FFT (fast Fourier transform) is performed on the received OFDM symbols by the FFT units (270). By means of a channel estimator (290) the channels are estimated and a beam weight generator (310) generates respective beam weights from the channels of the respective pilot tones of the respective subcarriers according to the channel estimation result. A beam weight multiplier (230) forms the uplink beam by multiplying the respective beam weights with the output of the signal repeater (220) and IFFT units (240) generate respective OFDM symbols which are transmitted via multiple antennas (250) through an uplink.Type: GrantFiled: November 10, 2004Date of Patent: February 15, 2011Assignees: Electronics and Telecommunications Research Institute, Samsung Electronics Co., Ltd., KT Corporation, SK Telecom Co., Ltd., KTFreetel Co., Ltd., Hanaro Telecom., Inc.Inventors: Seong-Rag Kim, In-Kyeong Choi, Dong-Seung Kwon, Seung-Ku Hwang
-
Patent number: 7872963Abstract: Disclosed is a MIMO-OFDM system, wherein the transmitter comprises a serial/parallel converter for converting continuously inputted symbols of the number of subcarriers to K parallel signals; a signal reproducer for reproducing K parallel signals by the number of transmit antennas L an eigenmode generator for generating eigenbeam of the reproduced signals outputted from the signal reproducer at each subcarrier, on the basis of Nf eigenbeam forming vectors which are fed back long-term and information of a best eigenbeam forming vector at each subcarrier which is fed back short-term, through the feedback device; and a plurality of inverse Fourier converters for receiving the signals outputted from the eigenmode generator and generating an OFDM symbol.Type: GrantFiled: November 25, 2004Date of Patent: January 18, 2011Assignee: Electronics and Telecommunications Research InstituteInventors: In-Kyeong Choi, Seong-Rag Kim, Dong-Seung Kwon, Jin-Ho Choi
-
Publication number: 20100322223Abstract: The present invention relates to a method of forming a random beam, and a beam forming apparatus. A quantization preprocessor and a random unitary matrix having a predetermined pattern are used to form a beam on a mobile terminal. A base station forms a beam using a codeword index of a quantization codebook received from a mobile terminal and channel quality information corresponding to the codeword index, and the mobile terminal generates the codeword index and the channel quality information using pilot signals generated by the base station. The number of pilot signals is equal to the number of transmitting antennas. Therefore, a codebook that has been known to both the mobile terminal and the base station is used, and the mobile terminal can select the codeword index for quantization, which makes it possible to selectively give diversity and thus improve the system efficiency.Type: ApplicationFiled: October 10, 2007Publication date: December 23, 2010Inventors: In-Kyeong Choi, Dong-Seung Kwon, Choong-Il Yeh, Ji-Won Kang, Chung-Yong Lee
-
Publication number: 20100310001Abstract: Disclosed is a transmitting/receiving method in a multi-user multiple-input multiple-output (MU-MIMO) channel. The transmitting method includes: performing QR decomposition on a Hermitian transpose matrix of a channel matrix to obtain a first matrix and a second matrix as a triangular matrix; obtaining a preprocessing matrix by using the first matrix; and forming an effective channel based on the preprocessing matrix by a block triangulation technique.Type: ApplicationFiled: June 24, 2008Publication date: December 9, 2010Applicants: SAMSUNG ELECTRONICS CO., LTD., Electronics and Telecommunications Research InstituteInventors: Choong il Yeh, In-Kyeong Choi, Young Seog Song, Seung Joon Lee, Byung-Jae Kwak, Ji Hyung Kim, Dong Seung Kwon, Joon Doo Kim, Ji Won Kang, Chung Yong Lee
-
Publication number: 20100215085Abstract: A receiver according to an exemplary embodiment of the present invention receives a transmitted signal, converts the signal to a predetermined symbol, and estimates channel information including a channel gain of a channel of the transmitted signal. In addition, the receiver generates an intermediate processing value for decoding the signal based on the estimated channel information and the symbol, and normalizes the intermediate processing value to the channel gain to generate a reference value. The generated reference value is used for a soft-decision value for decoding the signal. In addition, when the signal is decoded by using a hard-decision value, a constellation point value that is closest to the reference values is generated and set as the hard-decision value.Type: ApplicationFiled: December 9, 2005Publication date: August 26, 2010Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTEInventors: Seung-Joon Lee, Dong-Seung Kwon, Seong-Rag Kim, In-Kyeong Choi
-
Publication number: 20100189002Abstract: The present invention relates to a beamforming method and apparatus. A beamforming method for use in a base station for transmitting a plurality of streams through a plurality of antennas includes: receiving feedback information including information on a first codeword selected from a codebook including a plurality of codewords from each of a plurality of user terminals; grouping the plurality of user terminals by use of the feedback information from each user terminal; determining a user terminal to which a plurality of streams will be assigned of the plurality of user terminals, and determining a second codeword to be used for beamforming from the codebook by use of the feedback information of each user terminal and grouping information; and multiplying data to be transmitted through the plurality of steams by the second codeword and a unitary matrix.Type: ApplicationFiled: September 11, 2008Publication date: July 29, 2010Applicant: SAMSUNG ELECTRONICS CO., LTD.Inventors: In-Kyeong Choi, Dong Seung Kwon, Ji Won Kang, Chung Yong Lee
-
Method and device for optimizing codebook for quantized precoder by using steepest descent algorithm
Patent number: 7746936Abstract: In a method for optimizing a codebook including a quantized channel between a base station transmitter and a portable terminal: a) select the codebook to be optimized; b) a steepest descent algorithm is applied to respective codewords of the codebook selected in a), wherein the codewords are transformed so that a correlation between the codewords is minimized, and a function indicating the correlation between the codewords is differentiated and is multiplied by a predetermined step size and is used for a parameter for generating a new codeword in the steepest descent algorithm; c) it is determined whether the codebook including the codewords transformed in b) is optimized; and d) the codebook is stored when it is determined in c) that the codebook is optimized.Type: GrantFiled: May 2, 2007Date of Patent: June 29, 2010Assignee: Electronics and Telecommunications Research InstituteInventors: Dong-Seung Kwon, Young-Seog Song, In-Kyeong Choi, Chung-Yong Lee, Myeong-Cheol Shin, Myoung-Seog Kim, Seung-Joon Lee -
Publication number: 20100074364Abstract: The present invention relates to a precoder and a precoding method in a multi-user multi-antenna communication system. When a transmission part having a plurality of antennas transmits a plurality of signals to a receiving part having an antenna, the precoder and the precoding method using the same prevents system performance degradation caused by interference signals and efficiently reduces transmission power while changing the constellation rotary angle. When the power is controlled by using the precoder, the system performance is enhanced while not damaging the structural gain of the existing multi-user multi-antenna precoder.Type: ApplicationFiled: May 15, 2007Publication date: March 25, 2010Applicants: Electronics and Telecommunications Research Institute, Samsung Electronics Co., Ltd.Inventors: Dong-Seung Kwon, In-Kyeong Choi, Hyong-Woo Ku, Ji-Won Kang, Chung-Yong Lee
-
Patent number: 7634030Abstract: A transmission apparatus for a DS/CDMA system including a multiple-input multiple output MIMO antenna system is disclosed. The apparatus includes a transmitter for transmitting data by applying a different scramble code to each transmitted data through a plurality of transmitting antennas. The apparatus also includes a receiver for receiving the transmitted data by obtaining a diversity gain based on the maximum order of the diversity in order to effectively detect the data. The present invention achieves an excellent detection performance by receiving data with a full order of diversity, which is a multiple of the number of receiving antennas and the number of multipath, without complicated operation such as a decision feed equalizer.Type: GrantFiled: December 31, 2002Date of Patent: December 15, 2009Assignees: Electronics and Telecommunications, Research Institute - and - Korea Advanced Institute of Science and TechnologyInventors: Seong Rag Kim, Young Ho Jung, In-Kyeong Choi, Yong Hoon Lee
-
Publication number: 20090067513Abstract: A mobile station transmitting and receiving method and a corresponding mobile station transmitter and receiver of a smart antenna system for forming uplink eigenbeams of the OFDM/TDD (orthogonal frequency division multiplex/time division duplex), wherein OFDM symbols are received from a base station through a downlink via multiple antennas (250) and an FFT (fast Fourier transform) is performed on the received OFDM symbols by the FFT units (270). By means of a channel estimator (290) the channels are estimated and a beam weight generator (310) generates respective beam weights from the channels of the respective pilot tones of the respective subcarriers according to the channel estimation result. A beam weight multiplier (230) forms the uplink beam by multiplying the respective beam weights with the output of the signal repeater (220) and IFFT units (240) generate respective OFDM symbols which are transmitted via multiple antennas (250) through an uplink.Type: ApplicationFiled: November 10, 2004Publication date: March 12, 2009Inventors: Seong-Rag Kim, In-Kyeong Choi, Dong-Seung Kwon, Seung-Ku Hwang
-
Publication number: 20080240276Abstract: The present invention relates to a multi-input multi-output (MIMO) system for enhancing transmission performance. The MIMO system uses space-time encoding and transmit antenna selection methods, and includes a transmitter (100) and a receiver (200). The transmitter (100) includes N transmit antennas (130-1, 130-4) that are more than M tansrni antennas (130-1, 130-3) used for transmitting a signal to space channel, selects the M transmit antennas (130-1, 130-3) among the N transmit antennas (130-3 130-4), and transmits symbol by space-time encoding the symbol. The receiver (200) includes M receive antenna (120-1, 210-2) for receiving a signal from the space channel, detects an information symbol by using the signal received through the receive antenna (210-1, 210-2), generates transmit antenna selection information for selecting M transmit antennas (130-1, 130-3) among transmit antennas (i30-1, . . . 7130-4) with reference to a channel estimate, and returns the information to the transmitter.Type: ApplicationFiled: August 10, 2005Publication date: October 2, 2008Applicants: ELECTRONICS AND TELECOMMUNICATIONS RESERCH INSTITUTE, INDUSTRY-ACADEMIC COOPERATION FOUNDATION, YONSEI UNIVERSITYInventors: Young-Seog Song, Seong-Rag Kim, In-Kyeong Choi, Choong-ll Yeh, Seung-Joon Lee, Hyoung-Soo Lim, Kwang-Jae Lim, Yu-Ro Lee, Jong-Ee Oh, Dong-Seung Kwon, Seung-Ku Hwang, Chung-Yong Lee, Myeong-Cheol Shin
-
Publication number: 20080225975Abstract: A space-time code used for a transmitter to transmit a plurality of data symbols to a receiver in a MIMO system, the space-time code including a code word matrix for transmitting an amount of data symbols corresponding to a product of the number of transmit antennas and a spatial multiplexing rate during one block period, wherein a row index indicates combined signals transmitted through different transmit antennas and a column index indicates time slots that correspond to the number of transmit antennas, and wherein the number of data symbols allocated to each transmit antenna in a code block corresponds to the spatial multiplexing rate, and the data symbols are combined by different combining coefficients for each transmit antenna at every time slot, and simultaneously transmitted through different transmit antennas, and each transmit antenna transmits a different set of data symbols at every time slot.Type: ApplicationFiled: February 28, 2005Publication date: September 18, 2008Applicants: Electronics and Telecommunications Research Institute, Ajou University Industry Cooperation FoundationInventors: Seung-Joon Lee, Choong-Il Yeh, Dong-Seung Kwon, Seung-Ku Hwang, Hyoung-Soo Lim, In-Kyeong Choi, Jong-Ee Oh, Kwang-Jae Lim, Seong-Rag Kim, Young-Seog Song, Yu-Ro Lee, Seong-Keun Oh, Moon-Ii Lee