Abstract: Disclosed are a terminal and a base station for a distributed array massive multiple-input and multiple-output (MIMO) communication antenna system and an operation method thereof, wherein the terminal includes a distribution analog unit receiving a plurality of analog array receive signals based on a terminal antenna transmit signal from a virtual terminal through a plurality of distributed antenna arrays and a digital unit restoring the terminal antenna transmit signal based on the analog array receive signals and a channel parameter, and the base station includes an antenna receiving an analog receive signal based on a transmit beamforming input signal from a plurality of distributed antenna arrays, a virtual terminal restoring the transmit beamforming input signal based on an amplitude of the analog receive signal, and a terminal receive signal mapper mapping the transmit beamforming input signal to a base station transmit signal.

Abstract: An apparatus for transmitting and receiving signal and a method thereof are provided. The apparatus for transmitting signals selects at least one array of a plurality of arrays connected to the apparatus based on a spatial covariance matrix of an uplink from a terminal to the plurality of arrays, wherein the spatial covariance matrix ensures channel reciprocity at downlink from the plurality of arrays with the terminal, and forms a transmission beam to be transmitted to the terminal through the at least one selected array.

Abstract: Disclosed are a terminal and a base station for a distributed array massive multiple-input and multiple-output (MIMO) communication antenna system and an operation method thereof, wherein the terminal includes a distribution analog unit receiving a plurality of analog array receive signals based on a terminal antenna transmit signal from a virtual terminal through a plurality of distributed antenna arrays and a digital unit restoring the terminal antenna transmit signal based on the analog array receive signals and a channel parameter, and the base station includes an antenna receiving an analog receive signal based on a transmit beamforming input signal from a plurality of distributed antenna arrays, a virtual terminal restoring the transmit beamforming input signal based on an amplitude of the analog receive signal, and a terminal receive signal mapper mapping the transmit beamforming input signal to a base station transmit signal.

Abstract: An apparatus for transmitting and receiving signal and a method thereof are provided. The apparatus for transmitting signals selects at least one array of a plurality of arrays connected to the apparatus based on a spatial covariance matrix of an uplink from a terminal to the plurality of arrays, wherein the spatial covariance matrix ensures channel reciprocity at downlink from the plurality of arrays with the terminal, and forms a transmission beam to be transmitted to the terminal through the at least one selected array.

Abstract: Disclosed are a transmitter and a receiver for providing multi-layered multimedia services, and a method thereof. The transmitter for providing multimedia services includes a multiple description coding unit that performs multiple description coding (MDC) with respect to at least one source to thereby output a description sequence with respect to each of the at least one source, a description multiplexing unit that multiplexes the description sequence in units of descriptions to thereby output a single multiplexing description sequence, and a transmission code block processing unit that divides and modulates the single multiplexing description sequence to thereby generate a transmission block. Therefore, it is possible to provide high-quality multimedia services while ensuring graceful performance degradation and scalability.

Abstract: Provided are a transmitter and a receiver for providing a multi-layered multimedia service, and a method thereof. The transmitter includes: a Multiple Description Coding (MDC) unit configured to perform MDC on at least one source, and to output a description sequence for the at least one source; a Unequal Error Protection (UEP) grouping unit configured to output a UEP description sequence having a different number of description sequences constituting the description sequence according to a UEP level to which an importance level of the at least one source has been reflected; and a transmission code block processor configured to segment the UEP description sequence, to modulate each segmented UEP description sequence, and to generate a transmission block. Therefore, it is possible to ensure graceful degradation and scalability and provide a high-quality multimedia service.

Abstract: A layered transmission apparatus transmitting information regarding a plurality of layers includes: coding units coding an information bit of a corresponding layer to generate code bits; bit interleaving units bit-interleaving a corresponding code bit to generate interleaved symbols; a modulation unit classifying layers into layer groups, and modulating interleaved symbols corresponding to each of the groups to generate a modulation symbol of each of the groups; a gain control unit controlling gain of the modulation symbol of each of the groups; and an adding unit adding gain-controlled modulation symbols of the groups to generate a transmission symbol.

Abstract: Disclosed is a symbol synchronization obtaining apparatus robust to a frequency offset in a cell search of a wireless communication system. The symbol synchronization obtaining apparatus robust to a frequency offset in a cell search of a wireless communication system may include a sequence generator to generate a base sequence for obtaining the symbol synchronization, a synchronization pattern generator to generate a modified sequence based on the base sequence, and to generate a synchronization pattern by combining the modified sequence and the base sequence, a frequency mapping unit to perform mapping of transmission information to a time area and a frequency area, based on the synchronization pattern, for generating a transmission frame, and a transmitting unit to transmit the transmission frame.

Abstract: A receiver for receiving a layer-modulated signal includes: a base layer decoding unit configured to calculate a bit metric including code bit information of a base layer based on the reception signal and decode an information bit of the base layer; and at least one enhancement layer decoding unit configured to decode an information bit of an upper layer of a lower layer based on the decoding results of the lower layer, wherein the base layer decoding unit and the at least one enhancement layer decoding unit are sequentially connected according to the order of the corresponding layers.

Abstract: A reception apparatus including: a detection unit detecting extrinsic information based on a tentative symbol decision signal, a channel estimation signal, a noise variance estimation signal, and a received signal that are obtained from a previous iteration process; a Cyclic Redundancy Check (CRC) aided channel decoding unit outputting an interleaved bit or a posteriori information thereof based on the extrinsic information; a tentative symbol decision unit determining a tentative transmission symbol based on an output of the CRC aided channel decoding unit; a channel estimation unit estimating a channel based on an output of the tentative symbol decision unit; and a noise variance estimation unit estimating a noise variance based on the output of the tentative symbol decision unit and an output of the channel estimation unit is provided.

Abstract: A reception apparatus including: a detection unit detecting extrinsic information based on an output of a tentative symbol decision unit, an output of a channel estimation unit, and an output of a noise variance estimation unit that are obtained from a previous iteration process; a Cyclic Redundancy Check (CRC) aided channel decoding unit outputting an encoded and interleaved bit, or a posteriori information thereof based on the extrinsic information; the tentative symbol decision unit determining a tentative transmission symbol based on an output of the CRC aided channel decoding unit; the channel estimation unit estimating a channel based on an output of the tentative symbol decision unit or a pilot symbol; and the noise variance estimation unit estimating a noise variance or an initial noise variance based on the output of the tentative symbol decision unit and the output of the channel estimation unit is provided.

Abstract: Disclosed are a cooperation communication method and system using feedback signals. The cooperation communication method includes transmitting a packet to a base station by a terminal, determining, by the terminal, whether decoding of the transmitted packet is successfully performed using a feedback signal from the base station, and re-transmitting the packet to the base station by the terminal according to whether decoding of a packet of an adjacent terminal within a prescribed distance from the terminal is successfully performed.

Abstract: An iterative reception method and iterative receiver in a mobile communication system are provided. In order to remove inter-cell interference of a signal that is iteratively received in a multi-cell environment, a soft determination value of different cells excluding a specific cell is re-spread to be used. In addition, in order to improve reception performance of the iterative receiver that performs the interference removal by using the soft determination value, channel estimation is iteratively performed on the iteratively received signal by using a soft determination value of a previous order of the specific cell to update a channel estimation value. Accordingly, it is possible to reduce complexity of implementation and effectively remove the inter-cell interference by using the soft determination value.

Abstract: An iterative receiver and an iterative decoder are provided. The iterative receiver includes: an external decoder to decode the detected received signal; an impurity adder to add an impurity to an output signal of the external decoder; an interleaver to perform interleaving between the internal detector and the external decoder; and a de-interleaver to perform de-interleaving between the internal detector and the external decoder.

Abstract: In an iterative receiver, a signal detector estimates interference from an estimated transmitted signal, and cancels the estimated interference from a signal received through an antenna. A decoder performs channel decoding by using the interference cancelled received signal. A soft decision unit performs a soft decision process on the transmitted signal by using the channel decoded signal. A channel estimator estimates a channel by using the soft decision applied transmitted signal and the received signal. A covariance estimator estimates covariance on the sum signal of the interference and noise by using the soft decision applied transmitted signal, the received signal, and the estimated channel. A hard decision unit determines the transmitted signal by using the channel decoded signal after interference cancellation, channel decoding, estimated transmitted signal updating, channel estimation, and covariance estimation are iterated a number of times.

Abstract: There is provided an intercell interference mitigation apparatus for use in a terminal having a single reception antenna in a multi-cell downlink of an OFDMA system. The apparatus includes one or more parallel interference cancellers for canceling intercell interference by respreading soft decision values of cells other than a self cell; one or more LLR creation blocks for creating channel LLRs required for the soft decision for each of subcarriers, and producing channel soft outputs; one or more soft deciders for performing a soft decision of a self user symbol of the self cell in which interferences from other users are mitigated, and producing the soft decision values; and one or more channel estimation blocks for performing iterative channel estimation by respreading symbols of the soft decision values produced from the soft deciders.

Abstract: 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.

Abstract: A sphere decoder sets a Euclidean distance between a lattice vector obtained by using an MMSE or ZF estimate and a received signal as an initial radius, further reduces the initial radius, and searches lattices points included inside a hypersphere with the further reduced initial radius. In addition, one lattice vector having a minimum Euclidean distance is output. One dimension is selected to reduce an initial radius, and estimates in other dimensions are kept fixed, excluding the selected dimension. Then candidate lattice points are searched in the selected dimension, excluding a current estimate, such that a minimum Euclidean distance and a lattice point estimate corresponding to the minimum Euclidean distance are obtained. The initial radius is updated by the minimum Euclidean distance, and a final lattice vector is constructed by combining a lattice point estimate corresponding to the initial radius and the lattice point estimates in other dimensions.

Abstract: 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.

Abstract: A transmitter that transmits data using a multiple antenna includes a multiple description coder that generates a plurality of descriptions by performing multiple description coding of the data, and a multiple input multi output (MIMO) transmitting unit that performs channel coding of the plurality of descriptions and that transmits a description in which channel coding is performed through the multiple antenna.