Electronics and Telecommunications Research Institute

Other

Korea Advanced Institute of Science and Technology

Seong Rag Kim

Hyun Kyu Chung

Jeong Goo Lee

Junyoung Nam

In-Kyeong Choi

Seuck Ho Won

Young Wha Kim

Jung-Im Kim

Yong Hoon Lee

Hun Soon Lee

In Kyeong Choi

Sugbong Kang

Nam Jin Park

Young-Hoon Kim

Sung Ho Cho

Kapseok Chang

Young-Ho Jung

Keun Young Kim

Hee Soo Lee

Jun Young Nam

Jinho Choi

Young Ho Jung

Seung Chul Hong

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.

Base station and terminal for distributed array massive multiple-input and multiple-output (MIMO) communication antenna system

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.

Method and apparatus for transmitting/receiving signal in distributed-array massive MIMO system

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.

Apparatus for providing multimedia services and method thereof

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.

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.

Layered transmission apparatus and method, reception apparatus and reception method

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.

Symbol timing synchronization obtaining method and apparatus robust to frequency offset in cell search of wireless communication system

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.

Receiver and reception method for layered modulation

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.

Accelerated turbo transceiver and method for MIMO system

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.

Iterative estimator and method of channel and noise variance for multiple input multiple output orthogonal frequency division multiplexing system

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.

Cooperation communication method and system using feedback signal

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.

Iterative receiver and iterative decoder

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.

Intercell interference mitigation apparatus and method

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.

Data transmission apparatus for DS/CDMA system equipped with MIMO antenna system

A method for parallel type interference cancellation in a CDMA receiver, wherein minimum processing delay time is required while ensuring performance of an interference cancellation device, and space for embedding hardware for implementing the method can be reduced. The method for parallel type interference cancellation in a CDMA receiver, comprising: (a) when an over sample position of a received signal reaches the end of a symbol of a user, completing temporary detecting and recovering the symbol of the user; (b) generating a residual signal by using the recovered signal of the user and received signal state; and (c) detecting symbol information by obtaining an interference cancelled signal by adding the residual signal to the recovered signal of the user.

Method for parallel type interference cancellation in code division multiple access receiver

The present invention relates to a receiver applicable to a code division multiple access system having multiple transfer rates. In a CDMA system, when performing a de-spreading process to extract information from received data in which various terminal signals or multiple path signals are asynchronously mixed, interference between a plurality of users or paths tends to occur. The present invention proposes an interference canceller for effectively canceling the interference between the users or paths. For this, the present invention implements a parallel interference canceller for estimating in parallel interference signals from asynchronously received signals and canceling the estimated interference signals from the received signals. In the present invention, when implementing a parallel interference canceller for asynchronously received signals, as bit information of the received signals is not aligned in the same time frame, the following conditions are considered. First, the accuracy of interference cancellation is maintained. Second, the time delay of signal processing is minimized to minimize the time delay of the entire system. In the present invention, in order to achieve these objects, reproduction of interference signals and the subtraction operation are optimized based on the arrival points and end points based of the fastest signal and the latest signal among the asynchronously received signals.

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Daejeon, South Korea

Seong Rag Kim