Abstract: A terminal receives a map scheduling interval that is set to be greater than a multicast and broadcast service map transmission cycle by a base station from the base station, and receives a multicast and broadcast service map from the base station according to the received map scheduling interval.

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: A communication method of a source device according to an embodiment includes detecting a status of a first link directly connected from the source device to a destination device or a status of a second link connected from the source device to the destination device via a relay device, selecting any one of the first link and the second link based on a result of the detection, and transmitting data using the selected link.

Abstract: Provided is a communication method of a coordinator, the method including: receiving a relay search request frame for requesting a search for at least one relay station between a destination station and a source station; and transmitting, in response to the relay search request frame, a relay search response frame including a list of the at least one relay station so that the source station selects a target relay station from the at least one relay station.

Abstract: A portable apparatus including: a Radio Frequency (RF) unit to control a frequency of a signal to be measured, to broadcast the signal to be measured through multiple transmission antennas, to control a frequency of a received signal, and to send the received signal to the baseband unit, the received signal being received through multiple receiving antennas; and a baseband unit to generate and transmit, to the RF unit, the signal to be measured, to measure wireless channels for each of the multiple transmission antennas and wireless channels for each of the multiple receiving antennas based on the received signal output from the RF unit, to calculate a correlation for each of the multiple transmission antennas, and to calculate a correlation for each of the multiple receiving antennas based on the wireless channels for each of the multiple transmission and receiving antennas.

Abstract: Disclosed are an apparatus and method of determining an optimal cyclic delay value. The method of determining the optimal cyclic delay value includes determining a Signal-to-Interference and Noise Ratio (SINR) function depending on a diversity order; determining a channel estimation error variance function; and determining an SINR being required for a system according to the SINR function and the channel estimation error variance function.

Abstract: The present invention relates to a multi-antenna radio channel measurement system and method which generates a Time Division Duplex (TDD) timing signal and measures a two-way radio channel.

Abstract: Provided is a communication method of a coordinator in a wireless networks system that uses a reservation-based media access control (MAC). The communication method includes receiving, from a source device, a frame that requests a reservation resource for a relay device, to enable a frame that the source device transmits to a destination device to be relayed via the relay device, and allocating the reservation resource for the relay device, in response to the request.

Abstract: Provided is an apparatus for allocating a sequence to a synchronization channel for a node identification (ID), the apparatus including: a base node sequence generator to generate a base sequence that is a sequence for a node ID of a base node; a relay node sequence generator to generate a relay sequence that is a sequence for a node ID of a relay node by transforming the base sequence; a baseband signal generator to generate a baseband signal by mapping the base sequence or the relay sequence to a frequency domain and a time domain; and a transmitter to transmit the baseband signal.

Abstract: The present invention provides a wireless communication method used for transmitting and receiving a relay in a wireless local area network system. The wireless local area network system according to an embodiment of the present invention relates to a wireless communication method of setting a relay link through a relay and setting a transmission time point at which a data frame is transmitted in a source device by recognizing a propagation delay between devices, and the like when an operation mode of the set relay corresponds to a cooperating mode.

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: 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: Provided is a technology for extending a guard interval for individual user equipment in an OFDMA system. The transmitting apparatus includes: a guard interval extension processor for generating symbols with a guard interval extended by copying a part of a current symbol and pasting the copied part to a last part of a previous symbol; a Fourier Transform (FT) processor for receiving the processed symbols from the guard interval extension processor and performing an FT process on the received processed symbols; an Inverse Fast Fourier Transform (IFFT) processor for performing an IFFT process on the FT processed symbols from the FT processor; a mapping processor for mapping outputs of the FT processor to input points of the IFFT processor to load the FT processed frequency-domain data on corresponding sub-carriers; and a cyclic prefix inserter for inserting a cyclic prefix code to output of the IFFT processor.

Abstract: A method for clock synchronization between higher layers using synchronization information provided from lower layers in multi-clock communication system in which the higher layers and the lower layers use heterogeneous clocks is provided.

Abstract: Disclosed are a base station, a relay station, and a terminal according to a method for designing a cellular system for improving resource usage efficiency by reducing interference between relay stations and interference between the base station and the relay station. The relay station gets control signals that terminals served by the base station transmit, and registers terminals, levels of the control signals of which are bigger than a predetermined value, to a list of the interference terminals. The relay station checks an interference resource through resource allocation information of the base station, checks an available resource corresponding to a resource except the interference resource among a resource allocated by the base station, and allocates some of the available resource to the terminal.

Abstract: Disclosed is a cooperative relay station that relays between a base station and a mobile station when retransmitting a signal. Also, disclosed is a base station that receives a signal from a mobile station in mutual cooperation with the cooperative relay station. After the cooperative relay station receives and decodes a signal that the mobile station transmits to the base station or a service relay station, if an error of the decoded signal does not exist, it stores the received signal. If an error occurs when the base station decodes the signal that the mobile station transmits, the base station requests retransmission for the signal with the error to the cooperative relay station. If the cooperative relay station gets a request of retransmission, it transmits the signal that the base station requests to the base station.

Abstract: An apparatus for and method of transmitting and/or receiving a signal by using signaling point rotation in mutually cooperative relaying are provided.

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: Disclosed is a technique related to a method and apparatus for generating a preamble and a data frame for wireless communication, and to a synchronization estimation method using the preamble. According to the technique, a method for generating a frame for wireless communication is disclosed, wherein the method comprises: a step of generating a modified sequence using a first base sequence for synchronization estimation; and a step of allocating the first base sequence and the modified sequence to the frequency domain of a first timeslot to generate a preamble. The modified sequence includes a complex conjugated sequence of the first base sequence or a sequence having a code different from that of the first base sequence.

Abstract: A method and apparatus of accessing a channel in a wireless local area network is provided. A destination station receives a request to send (RTS) frame to allocate a network allocation vector from a source station over a first bandwidth and transmits a clear to send (CTS) frame over a second bandwidth to the source station in response to the RTS frame. The second bandwidth is dynamically determined when a first parameter has a predetermined value.