Abstract: The present invention relates to a transmitter and a transmission method in communication system using three Tx antennas in order to maximize STFBC coding gain. An input symbol sequence is transmitted through a plurality of Tx antennas in a predetermined method.

Abstract: A resource allocation method in a multiuser-multiple-input multiple-output/orthogonal frequency division multiple access (MIMO/OFDMA) system. In the multiuser-MIMO/OFDMA system feedback information is received from terminals. A channel gain and a transmission rate for each user are determined using the feedback information. An average channel gain for each user is computed according to the channel gain. The average number of bits for each user is determined according to the average channel gain. The number of subchannels for each user is computed according to the average number of bits for each user. At least one subchannel is allocated to each user according to the number of subchannels for each user. A modulation scheme for each of the at least one subchannel is determined. The resource allocation method adaptively allocates subchannels and bits according to channel environment, thereby considerably improving frequency use efficiency as well as a power gain.

Abstract: An Apparatus and a method for interference cancellation in a wireless communication system are provided. When a resource of an Interference Cancellation (IC) zone is allocated to a terminal traveling in a service coverage, resource allocation information relating to an IC zone of neighbor cells is gathered. Resource allocation information is generated relating to the resource allocated to the terminal comprising resource allocation information of the IC zone of the neighbor cells. The resource allocation information relating to the resource allocated to the terminal is transmitted to the terminal. Accordingly, when the interference is present, the interference cancellation is carried out to reduce the load on the terminal and enhance the reception performance.

Abstract: Provided is a transmitter apparatus in a MIMO wireless communication system. The transmitter apparatus includes a controller and a space-time encoder. The controller generates a space-time encoding code according to a multiplexing order, the number of transmitter antennas, and the number of receiver antennas. The space-time encoder space-time-encodes a TX signal using the generated space-time-encoding code.

Abstract: Apparatus and method for allocating a Channel Quality Information CHannel (CQICH) in a wireless communication system are provided. The method includes determining CQICH patterns required for users using information of one or more users to which CQICH resources are to be allocated, and selecting a CQICH pattern block, including all of the determined CQICH patterns, from among a plurality of pre-generated CQICH pattern blocks; and allocating CQICH sub-blocks corresponding to the users' required CQICH patterns using resource layout information of the CQICH sub-blocks corresponding to the CQICH patterns of the selected CQICH pattern block, and transmitting CQICH allocation information to a Mobile Station (MS).

Abstract: An apparatus and method for renewal-based resource allocation in a Broadband Wireless Access (BWA) system are provided. A Base Station (BS) allocates resources to a Mobile Station (MS) by resource allocation information. It is determined whether the MS requires continuous resource allocation or whether the MS does not have transmission data temporarily, when a resource allocation duration for downlink resources allocated to the MS has expired. One of resource allocation termination, resource allocation renewal, and temporary resource lending to another MS is performed according to the determination. Information for updating the resource allocation information is transmitted to the MS.

Abstract: Provided is an apparatus and method for resource allocation for multicast data in a broadband wireless access system. In the method, multicast packets are scheduled. Thereafter, a resource allocation message for the scheduled multicast packets divided into a second multicast resource allocation message including information of a user group using a multicast ID and a first multicast resource allocation message including information transmitted in common to users of the user group, and the corresponding message including changed information is transmitted for a change of information. Therefore, it is possible to reduce a waste of resource that is due to the duplicate transmission of some fields of resource allocation information about multicast data.

Abstract: A method for performing ranging by a mobile station in a communication system. The method includes transmitting a ranging sequence to a relay station; receiving an added signal of a reference sequence of the relay station and the ranging sequence, from the relay station; performing a correlation operation on each of the ranging sequence and the reference sequence in the added signal; estimating a time difference between the ranging sequence and the reference sequence depending on the correlation operation; and transmitting the signal to the relay station taking the time difference into account.

Abstract: Provided are a relaying method and system in a communication system having a BS, a MS for communicating with the BS, and an RS for relaying signals between the BS and the MS, in which the RS receives a first pilot sequence from the BS, replaces the first pilot sequence with a second pilot sequence, and transmits the second pilot sequence to the MS. Here, a partial cross correlation between the first and second pilot sequences is always ‘0’.

Abstract: A method and system for selecting an RS in an MS in a communication system are provided, in which the MS measures channel qualities between the MS and at least two RSs, and selects an RS for relaying signals between the MS and a BS from among the at least two RSs according to the channel quality measurements.

Abstract: A relaying method and system in a communication system having a Base Station (BS), a Mobile Station (MS) for communicating with the BS, and a Relay Station (RS) for relaying signals between the BS and the MS are provided. In the relaying method and system, the BS generates a BS pilot sequence and transmits the generated BS pilot sequence to the RS. wherein a partial cross correlation between the BS pilot sequence and an RS pilot sequence, being the BS pilot sequence relayed by the RS is always ‘0’. Accordingly, system capacity is more efficiently utilized.

Abstract: A space-time block coding (STBC) apparatus and method for a transmitter with four Tx antennas is provided. An input symbol sequence is transmitted through the four Tx antennas in a predetermined method based on feedback information received from a receiver, thereby improving the performance of an STBC.

Abstract: An apparatus and method for implementing SDMA in a multi-user multi-antenna system are provided, in which SDMA users are selected from among total users according to channel state information of the total users, and the number of transmission streams to be allocated to each of the SDMA users is determined by a tree search method.

Abstract: An apparatus and method for transmitting/receiving a signal in a communication system with a plurality of antennas are provided. Received modulation symbols of channel coded transmission information data are generated using a space-time mapping scheme and processed to RF symbols. The RF symbols are transmitted through antennas among the plurality of antennas.

Abstract: Disclosed is a mobile communication system using a Multiple Input Multiple Output (MIMO) scheme. A transmitter of the mobile communication system, generates a unitary space-time matrix to correspond to a codeword if the codeword to be transmitted in a first time interval is input, multiplies the unitary space-time matrix by a first final transmission matrix denoting signals transmitted in a second time interval before the first time interval, thereby generating a second final transmission matrix denoting signals to be transmitted in the second time interval, and transmits signals corresponding to the second final transmission matrix through a plurality of transmit antennas in the second time interval.

Abstract: Provided is a coding/decoding apparatus for an orthogonal frequency division multiple access (OFDMA) communication system that takes multiple users into consideration and uses block coding/decoding scheme. In the apparatus, a mapper determines paths through which information of users will be provided, according to states of sub-channels allocated to the users. A coding/decoding unit parallel-processes the information of the users through the paths selectively connected by the mapper. The coding/decoding unit includes coders/decoders having performance lower than the maximum processing performance determined taking into account a size of a processing block and the number of sub-channels.

Abstract: An adaptive interference suppression receiver for a DS/CDMA system includes: input signal generators outputting a part of received signals of receiver antennas that has a coding block's transfer code; adaptive filter blocks filtering a complex signal output from the input signal generators with a tap weight updated based on a constraint MMSE criterion and estimating phase and amplitude components of a specific user channel using the filtering output signal to generate a channel-estimated signal; a signal restorer combining the channel-estimated signal and the filtering output signal and restoring an original signal; a signal selector for selecting known training data signal or the restored signal; and error generators comparing the channel-estimated signal and the filtering output signal and calculating an error between the two signals.

Abstract: A transmitter in a multiple input multiple output (MIMO) communication system is provided. The transmitter includes a multiplexer for multiplexing an input bit stream into a plurality of bit streams, and outputting the bit streams in parallel; a bit-order rearranger for reordering bits constituting the bit streams, which are output from the multiplexer in the same time period, and outputting the reordered bits as reordered bit streams; and a modulator for modulating the parallel reordered bit streams output from the bit-order rearranger according to their associated modulation schemes, and transmitting the modulated symbols via their associated antennas.

Abstract: An efficient decoding scheme of a receiver in a wireless communication system including a transmitter for encoding data into quasi-orthogonal space-time block codes (STBCs) and transmitting the STBCs through a plurality of transmit antennas using fading channels, and a receiver for receiving data through a plurality of receive antennas. In the decoding scheme, channel matched filtering is performed on M N-dimensional equivalent reception vectors {right arrow over (y)}m received through M receive antennas and N-dimensional channel matched filtered vectors {right arrow over (y)}m,mat are outputted. P L-dimensional sub-channel matched filtered vectors {right arrow over (y)}m,mati are generated from each of the N-dimensional channel matched filtered vectors {right arrow over (y)}m,mat. P L-dimensional sub-equivalent channel matched filtered vectors {right arrow over (y)}m,mati are generated using the sub-channel matched filtered vectors {right arrow over (y)}m,mati.

Abstract: A method for transmitting to one cell a frame including broadcast channels in a cellular wireless communication system in which a base station supports a plurality of physical channels corresponding to the broadcast channels. The base station generates the frame and transmits the generated frame to a mobile station. The frame includes separate broadcast channels for the respective physical channels. A position, in the frame, of a first broadcast channel for a physical channel capable of supporting a mobile station having the worst channel state is fixed in all of transmission frames. The first broadcast channel includes positional information of the remaining broadcast channels except for the first broadcast channel. The mobile station detects only an address of a broadcast channel for a physical channel allocated thereto from the first broadcast channel among broadcast channels belonging to the frame.