Abstract: Disclosed are the design and implementation of a CSI feedback channel in a multi-carrier wireless communication system. An apparatus and a method for channel state feedback using arithmetic coding are provided to ensure efficiency and reliability of a system by transmitting the CSI while compressing the CSI with a predetermined compression rate selected depending on a channel state. The apparatus for CSI feedback in a wireless communication system performing channel estimation at a transmitter or a receiver by using a communication channel includes a transmitter terminal transmitting a signal for CSI measurement by using the communication channel, and a receiver terminal receiving the signal from the transmitter terminal, checking a channel state based on the received signal, and transmitting the signal to the transmitter terminal after compressing the signal according to the channel state.

Abstract: Disclosed is a device and procedure for coding a block low density parity check (LDPC) code having a variable length. The a device and procedure includes receiving an information word; and coding the information word into a block LDPC code based on one of a first parity check matrix and a second parity check matrix depending on a length to be applied when generating the information word into the block LDPC code.

Abstract: A hybrid forwarding apparatus and method for cooperative relaying in an OFDM network are provided. In a hybrid forwarding apparatus in a relay terminal, a forwarding scheme selector selects a forwarding scheme for transmission. An amplify and forward (AF) block amplifies data received from the forwarding scheme selector, if an AF scheme is selected. A decode and forward (DF) block decodes and encodes data received from the forwarding scheme selector, if a DF scheme is selected. A multiplexer provides the output data of the AF block and the DF block to an OFDM modulator.

Abstract: An apparatus and method is disclosed for frequency reuse to avoid interference between a Relay Station (RS) and a Mobile Station (MS) in a multi-hop relay system. The method includes measuring a preamble signal strength of a serving RS, measuring a preamble signal strength of a neighboring RS, and computing a preamble signal strength ratio using the preamble signal strength of the serving RS and the preamble signal strength of the neighboring RS.

Abstract: Disclosed is a method and apparatus for completely recovering received data with high reliability using LDPC codes without short-sized cycles in a digital communication system using an error-correcting code. The method includes performing exponent conversion of a predetermined number of exponent matrixes stored in advance in a memory so as to generate new exponent matrixes based on the exponent conversion, and generating new LDPC codes using the new exponent matrixes.

Abstract: A frame communication apparatus and method for a broadband wireless communication system are provided that employ a transmitter. In the transmitter, a control channel generating unit generates burst allocation information including a receiver identification (ID) with respect to a transmission packet, a burst generating unit constructs data burst by adding a header including a traffic ID to the transmission packet, and a transmitting unit transmits the burst allocation information and the data burst. An existing connection ID (CID) is subdivided into a user ID (UID) and a traffic ID (TID). The UID and the TID are recorded in a map channel message and a medium access control (MAC) header, respectively. Accordingly, an amount of information contained in a downlink map (DL-MAP) and uplink map (UL-MAP), and an amount of the MAC header of a data packet can be reduced.

Abstract: A method and apparatus is provided to improve an error correction capability for transmitted information, thereby reducing bit error rate and block error rate, and improving the reliability. The method and apparatus can generate error correcting codes having a good minimum distance characteristic, and which can achieve soft decision decoding and reduce the quantity of calculations for the decoding by using an IFHT decoder. Also, the method and apparatus can perform decoding while improving the error correcting capability of particular bits.

Abstract: A frequency overlay communication system that includes a first communication system for performing communication using a first frequency band being a preset bandwidth; and a second communication system for performing communication using a second frequency band being a second preset bandwidth, wherein the second frequency band includes the first frequency band.

Abstract: Disclosed are an apparatus and a method for generating a preamble sequence in an orthogonal frequency division multiplexing communication system including a reference base station and a plurality of non-reference base stations and employing m sub-carriers in a frequency domain. A reference preamble sequence having a length equal to n is generated and mapped on a one-to-one basis with n sub-carriers of the m sub-carriers. A final preamble sequence equivalent to the reference preamble sequence is generated when the base station is a reference base station, or a phase of the reference preamble sequence is shifted by a predetermined phase in order to generate a phase-shifted final preamble sequence when the base station is a non-reference base station, thereby minimizing interference between neighbor base stations.

Abstract: An optical communication apparatus includes an optical signal transmitting unit to output an optical signal; an optical signal receiving unit to receive an optical signal; a retro-reflector to retro-reflect the received optical signal in a direction opposite to an incident angle of the received optical signal; and a control unit to direct the retro-reflector to receive the optical signal and to retro-reflect a response signal, which includes the received optical signal and data to be transmitted, in response to the received optical signal.

Abstract: Disclosed are a remote control method in a remote control system including a display panel, and a terminal for remote-controlling the display panel, and the remote control system. The remote control system includes a terminal for transmitting a light signal to a point on the screen of a display panel according to user input, and a display panel for executing an operation corresponding to the light signal received point.

Abstract: Provided is an apparatus and method for transmitting/receiving data in a communication system using a structured Low Density Parity Check (LDPC) code. The transmitter performs structured LDPC coding on input information data using a structured LDPC code, parallel-converts a structured LDPC codeword generated by performing the structured LDPC coding, in units of groups having a predetermined size, and transmits data. The receiver receives a plurality of parallel data streams, serial-converts the received parallel data streams in units of groups having a predetermined size, and performs structured LDPC decoding on the data which was serial-converted group by group, using a structured LDPC code.

Abstract: A transmitter for minimizing a PAPR in OFDM communication system. The transmitter includes: a precoder for coding input symbols so that a signal rotation is generated, and generating a complex vector including the coded symbols; an encoder for performing a frequency-space mapping for the symbols generated as the complex vector according to a predetermined scheme; a random mapper for randomly mapping the symbols for which the frequency-space mapping has been performed on a frequency plane through at least one transmit antenna; an Inverse Fast Fourier Transform (IFFT) unit for performing an IFFT for the symbols for which the frequency-space mapping has been performed; and a gradient algorithm unit for receiving IFFTed signals from the IFFT unit and reducing the PAPR.

Abstract: An apparatus and method for controlling a reverse data rate in a mobile station. The method includes determining whether the mobile station has sufficient power to transmit at an increased data rate compared to a current data rate, and transmitting a determination result to a base station.

Abstract: An apparatus and a method for selecting an antenna appropriate for a data service type in a communication system employing multiple antennas. The method of performing data communication through a transceiver using multiple antennas includes determining the type of the data services contained in a received signal, selecting one of the multiple antennas with a communication quality corresponding to the type of the data services, and employing the selected antenna to perform the data communication.

Abstract: A broadband wireless communication system supporting frequency overlay is provided. Operations of a base station includes checking whether it is time to transmit a common control signal; switching positions of a first Common Control Channel and a second Common Control Channel applied to a previous transmission of the common control signal while mapping a common control signal to the first Common Control Channel and the second Common Control Channel positioned in different Frequency Assignments; and transmitting the common control signal via the first Common Control Channel and the second Common Control Channel that are switched.

Abstract: Disclosed is an apparatus and method for encoding/decoding a space time block code in a mobile communication system using a multiple input multiple output scheme. In a transmitter employing a plurality of transmit antennas in the mobile communication system, if a signal to be transmitted is input, the transmit signal is pre-encoded according to a preset coding scheme, the pre-encoded signal is space-time mapped according to a number of the transmit antennas to employ a preset space time block coding scheme, and the space-time mapped signal is transmitted through the transmit antennas by applying the preset space time block coding scheme to the space-time mapped signal.

Abstract: An apparatus and method of transceiving a bit stream, by which a video bit stream is stably transmitted by the effective use of two logic channels when communication is established by the two logic channels during transmission of the video bit stream in a communication network, is provided. In this method, a source is encoded into a bit stream using a predetermined type of coding. Then, the encoded bit stream is transmitted to each communication protocol layer, while the header of each communication protocol layer is added to a payload. The header is transmitted separately from the bit stream.

Abstract: A reverse transmission controlling method in a mobile communication system. After receiving forward information commanding a reverse data rate change on a forward channel from a base station, a mobile station increases its reverse data rate to a data rate equal to or lower than a maximum data rate if the forward information commands a reverse data rate increase, determines whether the increased data rate can be further increased for the next frame, and transmits the determination result with information representing the increased data rate to the base station.

Abstract: An apparatus and method for SFBC coding and decoding in a communication system using a plurality of (Nt) Tx antennas are provided. In a transmitter using Nt transmit antennas, a pre-coder pre-codes an input symbol sequence using a pre-coding matrix. The pre-coding matrix is produced by puncturing a unitary matrix in a predetermined method. An encoder generates a plurality of vectors by grouping the symbols of the pre-coded symbol sequence by twos, space-frequency maps each of the vectors by encoding each of the vectors in an Alamouti coding scheme, and provides each of the space-frequency mapped symbols to a predetermined OFDM modulator.