Abstract: A receiver for receiving a signal including a plurality of symbols through a multiple input multiple output (MIMO) channel, and an operation method of the receiver are provided. The receiver includes a demodulator configured to calculate, for each physical channel, Euclidean distances of one or more of the received symbols with respect to all candidate vectors included in an initial candidate vector set and to output information about the Euclidean distances. A vector set detector may select, based on the information, one of a plurality of candidate vector sets having different sizes, as a subsequent candidate vector set for calculating a log likelihood ratio (LLR) of other symbols of the plurality of symbols or an LLR with respect to a second signal received following the first signal.

Abstract: A receiver for receiving a signal including a plurality of symbols through a multiple input multiple output (MIMO) channel, and an operation method of the receiver are provided. The receiver includes a demodulator configured to calculate, for each physical channel, Euclidean distances of one or more of the received symbols with respect to all candidate vectors included in an initial candidate vector set and to output information about the Euclidean distances. A vector set detector may select, based on the information, one of a plurality of candidate vector sets having different sizes, as a subsequent candidate vector set for calculating a log likelihood ratio (LLR) of other symbols of the plurality of symbols or an LLR with respect to a second signal received following the first signal.

Abstract: A method of iterative detection and decoding by a receiver and a receiver for iterative detection and decoding. The method includes generating a channel estimated value using a received signal; storing the generated channel estimated value; generating a Log Likelihood Ratio (LLR) value using the received signal and the stored channel estimated value; and generating a decoded bit as feedback information using the LLR value, wherein the LLR value is iteratively regenerated using the generated feedback information, the stored channel estimated value, and the received signal.

Abstract: A method of iterative detection and decoding by a receiver and a receiver for iterative detection and decoding. The method includes generating a channel estimated value using a received signal; storing the generated channel estimated value; generating a Log Likelihood Ratio (LLR) value using the received signal and the stored channel estimated value; and generating a decoded bit as feedback information using the LLR value, wherein the LLR value is iteratively regenerated using the generated feedback information, the stored channel estimated value, and the received signal.

Abstract: Disclosed is a method and a radar apparatus for transmitting a transmission signal at a controlled timing in order to avoid signal interference, thereby exactly detecting a target object without misrecognition.

Abstract: A receiving method and apparatus in a Multiple-Input Multiple-Output (MIMO) communication system are provided. The method includes receiving reception signals through a plurality of reception antennas, grouping symbols corresponding to the reception signals, respectively, into a preset number of groups, and rearranging symbols of the respective groups, transforming the reception signals by applying QR decomposition to the reception signals, sequentially canceling interference due to each of total possible candidate symbols for a first symbol based on an order of the rearranged symbols in the transformed reception signals, determining a portion of the total possible candidate symbols to be a candidate symbol set for each remaining symbol, except for the first symbol, using the interference-canceled reception signal, and determining log-likelihood ratio values of the first symbol, which are to be used upon decoding the received signals, using candidate symbols for the first symbol and each remaining symbol.

Abstract: A Spatial Multiplexing Multiple Input Multiple Output (SM-MIMO) communication system, which generates Q and R matrices through QR decomposing a channel matrix in an array order corresponding to an order of transmission antennas of a signal transmission device, determines a detection order of transmission symbols included in a transmission symbol vector, QR decomposes a reception signal vector and generates the QR decomposed reception signal vector as a transformed reception signal vector, substitutes all of transmittable candidate symbols for a transmission symbol corresponding to a first detection order among the transmission symbols and sequentially removes interference in the transformed reception signal vector, detects candidate symbols of transmission symbols corresponding to a remaining detection order from the interference-removed transformed reception signal vector, combines the detected candidate symbols, detects candidate symbol vectors, and calculates Log-Likelihood Ratio values of bits included in

Abstract: An apparatus for adaptively decoding based on a channel variation at a receiver of a communication system supporting an Alamouti mode is provided. The apparatus includes a channel variation estimator for estimating the channel variation; a channel estimator for estimating a channel value of successive channel periods or a channel value of each channel period by comparing the estimated channel variation with a threshold; an Alamouti decoder for decoding a receive signal using an Alamouti method when the estimated channel variation is less than or equal to the threshold; and a Spatial Multiplexing (SM) decoder for decoding the receive signal using an SM method having a square channel matrix when the estimated channel variation is greater than the threshold.

Abstract: Detection apparatus and method for achieving performance close to a Maximum Likelihood (ML) detection having optimal performance and reducing computational complexity in a Multiple-Input Multiple-Output (MIMO) system including a plurality of transmit antennas and receive antennas are provided. The apparatus includes a hard decision part for confirming an initial hard decision value of a receive symbol vector; a candidate symbol selector for selecting candidate symbols restricted to neighbor values of the initial hard decision value; and an interference canceller for canceling interference in the selected candidate symbols and selecting a final candidate symbol from the received symbols using a result of the interference cancellation.

Abstract: A method and an apparatus for estimating a symbol timing offset in an Orthogonal Frequency Division Multiplexing (OFDM) based communication system are provided. A Carrier to Interference Ratio (CIR) of an Reference Signal (RS) is acquired using received pilot signals. The RS CIR includes power information on channel components of the RS. A CIR of a Secondary Synchronization Channel (S-SCH) is acquired using the received pilot signals. The S-SCH CIR includes power information on channel components of the S-SCH. Unnecessary channel components are suppressed from the RS CIR using the S-SCH CIR. Real channel components of the RS remain. An observation window is set having a predetermined duration for windowing the real channel components of the RS. A first arriving channel component is searched for within the observation window. A start point of data is estimated using the first arriving channel component.

Abstract: Disclosed is a method and a radar apparatus for transmitting a transmission signal at a controlled timing in order to avoid signal interference, thereby exactly detecting a target object without misrecognition.

Abstract: Disclosed is a method and a radar apparatus for transmitting a transmission signal through a changing transmission frequency band in order to avoid signal interference, thereby exactly detecting a target object without misrecognition.

Abstract: A Spatial Multiplexing Multiple Input Multiple Output (SM-MIMO) communication system, which generates a Q matrix and an R matrix through QR decomposing a channel matrix in an array order corresponding to an order of transmission antennas of a signal transmission device, determines a detection order of transmission symbols included in a transmission symbol vector, QR decomposes a reception signal vector and generates the QR decomposed reception signal vector as a transformed reception signal vector, substitutes all of transmittable candidate symbols for a transmission symbol corresponding to a first detection order among the transmission symbols and sequentially removes interference in the transformed reception signal vector, detects candidate symbols of transmission symbols corresponding to a remaining detection order from the interference-removed transformed reception signal vector, combines the detected candidate symbols, detects candidate symbol vectors, and calculates Log-Likelihood Ratio values of bits i

Abstract: A radar apparatus, an antenna apparatus, and a data acquisition method are provided, which can reduce the size of a radar apparatus as well as maintaining angular resolution.

Abstract: A receiving method and apparatus in a Multiple-Input Multiple-Output (MIMO) communication system are provided. The method includes receiving reception signals through a plurality of reception antennas, grouping symbols corresponding to the reception signals, respectively, into a preset number of groups, and rearranging symbols of the respective groups, transforming the reception signals by applying QR decomposition to the reception signals, sequentially canceling interference due to each of total possible candidate symbols for a first symbol based on an order of the rearranged symbols in the transformed reception signals, determining a portion of the total possible candidate symbols to be a candidate symbol set for each remaining symbol, except for the first symbol, using the interference-canceled reception signal, and determining log-likelihood ratio values of the first symbol, which are to be used upon decoding the received signals, using candidate symbols for the first symbol and each remaining symbol.

Abstract: A method and an apparatus for estimating a symbol timing offset in an Orthogonal Frequency Division Multiplexing (OFDM) based communication system are provided. A Carrier to Interference Ratio (CIR) of an Reference Signal (RS) is acquired using received pilot signals. The RS CIR includes power information on channel components of the RS. A CIR of a Secondary Synchronization Channel (S-SCH) is acquired using the received pilot signals. The S-SCH CIR includes power information on channel components of the S-SCH. Unnecessary channel components are suppressed from the RS CIR using the S-SCH CIR. Real channel components of the RS remain. An observation window is set having a predetermined duration for windowing the real channel components of the RS. A first arriving channel component is searched for within the observation window. A start point of data is estimated using the first arriving channel component.

Abstract: Detection apparatus and method for achieving performance close to a Maximum Likelihood (ML) detection having optimal performance and reducing computational complexity in a Multiple-Input Multiple-Output (MIMO) system including a plurality of transmit antennas and receive antennas are provided. The apparatus includes a hard decision part for confirming an initial hard decision value of a receive symbol vector; a candidate symbol selector for selecting candidate symbols restricted to neighbor values of the initial hard decision value; and an interference canceller for canceling interference in the selected candidate symbols and selecting a final candidate symbol from the received symbols using a result of the interference cancellation.

Abstract: An apparatus for adaptively decoding based on a channel variation at a receiver of a communication system supporting an Alamouti mode is provided. The apparatus includes a channel variation estimator for estimating the channel variation; a channel estimator for estimating a channel value of successive channel periods or a channel value of each channel period by comparing the estimated channel variation with a threshold; an Alamouti decoder for decoding a receive signal using an Alamouti method when the estimated channel variation is less than or equal to the threshold; and a Spatial Multiplexing (SM) decoder for decoding the receive signal using an SM method having a square channel matrix when the estimated channel variation is greater than the threshold.

Abstract: An apparatus and method for transmitting data on a plurality of frequency sub-channels for a plurality of successive symbol periods through a plurality of transmit antennas in an OFDM system. In the data transmitting apparatus, an S/P converter converts information symbols received from a data source to an information symbol vector, a coder generates at least one code symbol vector using the information symbol vector in at least one symbol period, an IFFT unit generates at least as many transmission signal vectors as twice the number of code symbol vectors generated in the coder for the one symbol period, a plurality of P/S converters each convert the transmission signal vectors to a transmission signal stream, and a guard interval inserter inserts a guard interval into each of the transmission signal streams received from the P/S converters.

Abstract: An apparatus and method for transmitting data on a plurality of frequency sub-channels for a plurality of successive symbol periods through a plurality of transmit antennas in an OFDM system. In the data transmitting apparatus, an S/P converter converts information symbols received from a data source to an information symbol vector, a coder generates at least one code symbol vector using the information symbol vector in at least one symbol period, an IFFT unit generates at least as many transmission signal vectors as twice the number of code symbol vectors generated in the coder for the one symbol period, a plurality of P/S converters each convert the transmission signal vectors to a transmission signal stream, and a guard interval inserter inserts a guard interval into each of the transmission signal streams received from the P/S converters.