Abstract: A method of and apparatus for operating a Coexistence Beacon Protocol (CBP) packet transmitter in a Cognitive Radio (CR)-based wireless communication system is provided. The method includes, identifying a Self-Coexistence Window (SCW) regular pattern of neighbor Wireless Regional Area Networks (WRANs), if vacant SCW slots are not periodically occurring, selecting a WRAN as a contender among the neighbor WRANs, performing a contention for transmitting the CBP packet with the contender within SCW slots that are occupied by the WRAN, and configuring an SCW usage pattern so that an SCW usage period of the CBP packet sender is double that of an SCW usage period of the contender when winning in the contention.

Abstract: A method of operating a Data Base (DB) server for storing spectrum condition information on a licensed system in a Cognitive Radio (CR)-based wireless communication system and a CR-based wireless communication system are provided. The method includes determining changes in the spectrum condition information on the licensed system, recalculating maximum Equivalent Isotropically Radiated Power (EIRP) allowed for each channel of CR-based devices registered in a list, and transmitting information regarding the recalculated maximum allowed EIRP.

Abstract: Provided are an apparatus and a method for transmitting a CBP packet for communication information sharing between base stations in a CR-based wireless communication system. In the method, a CBP packet including a CBP identifier is transmitted to a base station of adjacent cells via one SCW slot. A CBP identifier list for successfully received CBP packets is received from the base station of the adjacent cells. When the CBP identifier is included in the CBP identifier list, the SCW slot is occupied.

Abstract: An apparatus and a method for selecting a candidate channel to change an operating channel so as to minimize effect of interference in a wireless communication system using a Cognitive Radio (CR) function are provided. The method includes confirming an operating channel of at least one neighbor cell and candidate channel set to a third group by the neighbor cell; setting a candidate channel used as the operating channel of the neighbor cell among at least one candidate channels changeable to the operating channel, to a third group of lowest priority; setting candidate channels set to the third group of the neighbor cell among candidate channels not set to the third group, to a second group; and setting candidate channels set to neither the second group nor the third group, to a first group of highest priority.

Abstract: A wireless communication system based on a Cognitive Radio (CR) is provided. A method includes checking channels unused by a licensed system through a spectrum sensing; selecting one of the channels unused by the licensed system as a control channel based on a channel quality per channel; and transmitting control information to terminals within a cell over the control channel.

Abstract: An apparatus and method for transmitting Coexistence Beacon Protocol (CBP) in a cognitive radio system are provided. The apparatus includes a detector, a controller, and a transmitter. The detector scans channels on which neighboring Base Stations (BSs) operate through a plurality of directional antennas. The controller links the plurality of directional antennas with BSs, respectively. The transmitter receives a CBP packet through the directional antenna linked with the BS, and transmits the received CBP packet to at least one or more other BSs linked with at least one or more other directional antennas.

Abstract: A wireless communication system using multiple channels is provided. An apparatus includes an allocator for, when bursts are allocated to an Accessing Terminal (AT) which utilizes a plurality of channels at the same time, allocating the same amount of the bursts to each channel in use; a generator for, when a map message to be transmitted in a primary channel of the AT is generated, generating the map message which comprises allocation information of the bursts allocated to the AT; and a transmitter for transmitting the map message in the primary channel of the AT.

Abstract: A method and apparatus for channel management in a Cognitive Radio (CR) system supporting multiple channels are provided. The method includes generating a candidate channel set from an available channel list, configuring a backup channel set by combining at least one candidate channel, and updating the backup channel set when a channel change event occurs. Accordingly, the multiple channels can be effectively used in CR communication.

Abstract: A method and apparatus for estimating a geo-location of a terminal in a wireless communication system are provided. In a method of operating a terminal for providing geo-location information in a cognitive ratio (CR) system, the method includes obtaining first ranging information and transmitting a first ranging code to a base station (BS) in a network entry process; receiving an allocated second ranging resource from the BS; and transmitting a second ranging code.

Abstract: Provided is an apparatus and method for controlling power in a cognitive radio wireless communication system, the method comprising: performing channel scheduling and the first power control for at least one terminal; checking whether the at least one terminal exist within constraint area, and determining whether the at least one terminal within constraint area cause interference to incumbent system; and performing the secondary power control so that an allocating power may be less than the maximum tolerable interference.

Abstract: A signal detection apparatus and method in a Multiple Input Multiple Output (MIMO) wireless communication system are provided. The apparatus includes a receiver for receiving training symbol vectors and a data signal vector from a transmitting end through a plurality of receive (Rx) antennas and a detector for expanding the training symbol vectors into second- or higher-order polynomials, for generating a weighting parameter vector for multivariate polynomial expansion of the data signal vector by using the polynomials expanded from the training symbol vectors and thereafter for expanding the data signal vector into a second- or higher-order multivariate polynomial using the weighting parameter vector, and for detecting Transmit (Tx) values of the data signal vector from the multivariate polynomial. Therefore, signal detection performance in a Multiple Input Multiple Output (MIMO) wireless communication system resembles that of a non-linear scheme while complexity resembles that of a linear scheme.

Abstract: A Relay System (RS)-based cellular network transmission method for MT having a function of single input and single output is provided. The method includes transmitting broadcast information to all RSs and Mobile Terminals (MTs); transmitting required data to each RS in an Orthogonal Frequency Division Multiplexing (OFDM) mode; performing the operations of selection of modulation scheme, addition of CP, addition of symbols for channel estimation and selection of OFDM symbols; feeding feedback information to the Base Station (BS); transmitting a synchronization request to the BS; transmitting a synchronization acknowledgement to the RS; transmitting information to each MT belonging to the BS; transmitting information to each MT belonging to the RS; the MT belonging to the BS transmitting ACK/NACK information to the BS; the MT belonging to the RS transmitting ACK/NACK information to the BS; and the BS informing the RS of the received ACK/NACK information.

Abstract: A method for controlling a local printer connected to a PC (Personal Computer) using a portable terminal for mobile communication in a home network system. The method controls the printer serving as a local device not included in the home network system by means of the portable terminal for mobile communication serving as a home networking device. In the home network system including the portable terminal and the PC, the portable terminal is connected to the PC by means of home networking. Content within the PC is searched for and selected using the portable terminal. The portable terminal sends a print request message to the PC so that the local printer can print the selected content. In response to the print request message, the PC creates a print job and transfers the selected content to the local printer so that the local printer can print the transferred content. The portable terminal receives a result of the print job from the local printer through the PC.

Abstract: A system for transmitting/receiving resource allocation information in a wireless mobile communication system is provided. A transmission apparatus allocates a data burst in a frame, the data burst including a two-dimensional region of a time domain and a frequency domain, and transmits resource allocation information on the allocated data burst. A reception apparatus receives the resource allocation information from the transmission apparatus, and detects a region of the frame where the data burst is allocated, using the received resource allocation information. The resource allocation information includes information on a start point and an end point of the data burst. The start point indicates a point which is spaced apart from an start point of the frame by a first offset value in the time domain, and is spaced apart from the start point of the frame by a second offset value in the frequency domain.

Abstract: An apparatus and method for detecting a signal in a broadband wireless communication system are provided. In a Base Station, an offset estimator estimates frequency offsets of a signal received from each of a plurality of Mobile Stations (MSs), a channel estimator estimates a channel matrix having channel coefficients of subcarriers as elements, for each MS, a modeler models the received signals using the frequency offsets of the MSs and the channel matrices of the MSs, and a detector detects signals transmitted from the MSs using the modeled received signals.

Abstract: A method and apparatus for joint unicast using multi-user superposition coding in a wireless relay system are provided. A BS superposition-encodes first and second data messages directed to first and second MSs, respectively, scheduled at a current scheduling instant. The first and second data messages carry first and second information bit streams for the first and second MSs, respectively. The first MS has a relatively good direct link to the BS, and the second MS has a relatively bad direct link to the BS. The superposition-coded data is transmitted to the first MS and an RS connected between the BS and the first and second MSs. The RS receives the superposition-coded data from the BS, extracts the second information bit stream by decoding the superposition-coded data, and transmits a third data message carrying the second information bit stream to the first and second MSs.

Abstract: A system and method for transmitting and receiving a signal in a communication system using a relay scheme. A base station receives a first signal in a first time interval from a first mobile station which is at least one mobile station located in a third region which is a region where a first region which is a region of the base station itself overlaps with a second region which is a region of a relay station. The relay station receives a second signal in the first time interval from a second mobile station which is at least one mobile station located in a fourth region which is a region not overlapping with the first region in the second region, and receives the first signal from the first mobile station. The relay station transmits a third signal including the first signal and the second signal to the base station in a second time interval. The base station receives the third signal in the second time interval, and cancels the first signal from the third signal to detect the second signal.

Abstract: A relay wireless communication system is provided. A Relay Station (RS) includes a buffer for storing packets to be sent to at least one Mobile Station (MS); a scheduler for allocating resources to the at least one mobile station of which the packets are stored to the buffer; a generator for generating a message which comprises information about at least one mobile station of which packets are not stored to the buffer; and a communicator for sending the message to a Base Station (BS) and sending the packets stored to the buffer to the at least one mobile station allocated the resources.

Abstract: An apparatus and a method for selecting one of a plurality of relay modes in a wireless communication system are provided. The method includes checking a channel state between a Mobile Station (MS) and each of at least one Relay Station (RS), selecting the relay mode for supporting a relay service using the determined channel state between the MA and each of the at least one RS, and providing the relay service to the MS using the selected relay mode. Thus, system throughput and outage performance can be enhanced by using the appropriate relay mode based on the MS distribution or the channel condition.

Abstract: An apparatus and a method for joint power control in a wireless communication system are provided, in which customer premise equipments to be serviced are selected by scheduling, upon receipt of service requests from the customer premise equipments, the interference level of each of the selected customer premise equipments that affects an incumbent system is calculated, a total interference level affecting the incumbent system is calculated by summing the interference levels of the selected customer premise equipments, and a transmit power of the each customer premise equipment is reduced, if the total interference level is larger than a threshold.