Abstract: An apparatus and method for generating an RS SCH in a wireless communication system are provided, in which a base station checks a BS SCH sequence and a mask sequence, and generates an RS SCH sequence by XOR-operating the BS SCH sequence and the mask sequence.

Abstract: A method is provided for transmitting/receiving data in a communication system. The method includes measuring, by a Mobile Station (MS), states of channels which are allocated in a scheme prearranged with a Base Station (BS), and encoding measured channel state information in a scheme corresponding to an allocation scheme of the allocated channels; and configuring a message including the encoded channel state information, and transmitting the configured message to the BS.

Abstract: A frame configuration method and apparatus for sending data via an RS in a broadband wireless communication system are provided. In the reception mode, the RS monitors reception of data in an (n?1)th frame from an MS and reception of data in an nth frame from a BS. The RS classifies the data received from the MS and the data received from the BS as combinable data to be sent in combination or as non-combinable data to be sent separately, and stores the classified data distinguishably. When the RS transitions to a transmission mode, it determines whether to XOR-operate or mask the stored data. If the stored data can be masked, the RS XOR-operates the stored data and sends the masked data to the BS and the MS.

Abstract: Apparatus and method for performing Automatic Retransmission reQuest (ARQ) in a wireless relay communication system are provided, which include performing ARQ with the base station (BS), transmitting data successfully received from the BS to mobile station (MS), and retransmitting corresponding data to the MS when a retransmission indication message is received from the BS. Since the relay station (RS) relays only the errorless data to the receiver, the reliability of the data received at the receiver can be enhanced. The load on the RS can be reduced because the transmitter controls the ARQ.

Abstract: A system for performing cell acquisition in a frequency overlay communication system having a first frequency band and a second frequency band including the first frequency band. A base station (BS) generates a reference signal used for identifying a cell using a specific sequence in a predetermined frequency band, and transmits the reference signal. A mobile station (MS) receives the reference signal to determine whether the BS uses the first frequency band or the second frequency band, determines a reference signal having a maximum correlation value through correlation calculation with at least one predefined sequence, and detects a BS identifier (ID) corresponding to the determined reference signal.

Abstract: A system and method for transmitting downlink schedule in a WiMax/WiBro relay system is proposed in present invention. In present invention, the task of transmitting the schedule is dispersed from the BS to both of the BS and RS so that several RS may transmit the schedule items simultaneously and therefore the resource of the system is saved.

Abstract: A method for transmitting a signal by a transmitter in a frequency overlay communication system. The method includes generating y first signal groups by shuffling input information data with a length yN on an N-by-N grouping basis according to a first shuffling scheme; generating y second signal groups by performing N-point IFFT on each of the first signal groups; generating y third signal groups by multiplying each of the second signal groups by preset values; generating N fourth signal groups by de-shuffling the third signal groups on a y-by-y grouping basis according to a de-shuffling scheme; generating N fifth signal groups by performing y-point IDFT on each of the fourth signal groups; generating y sixth signal groups by shuffling the fifth signal groups according to a second shuffling scheme, and serial-converting the sixth signal groups; and performing a transmission RF process on the serial-converted signal and transmitting the RF-processed signal to a receiver.

Abstract: An apparatus and operation method of a Base Station (BS) for allocating a radio resource in a Cognitive Radio (CR) wireless communication system includes, when a licensed system is activated, determining whether each of User Terminals (UTs) located in a cell satisfies Quality of Service (QoS). If all of the UTs satisfy the QoS, a binary message indicating ‘on’ is broadcasted to neighbor BSs. If at least one of the UTs does not satisfy the QoS, a binary message indicating ‘off’ is broadcasted to the neighbor BSs, and when the binary message indicating ‘off’ is received from at least one of the neighbor BSs, the binary message indicating ‘off’ is broadcasted to the UTs.

Abstract: An apparatus and a method for transmitting a Coexistence Beacon Protocol (CBP) packet in a Cognitive Radio (CR) wireless communication system are provided. In the method for transmitting CBP packet in a transmitter that operates in a scalable Orthogonal Frequency Division Multiple Access (OFDMA) mode, a priority is given to each channel of one or more channels based at least partly upon channel use statuses of two or more neighbor Wireless Regional Area Networks (WRANs). Whether a Quality of Service (QoS) for CBP packet transmission for each channel is met is sequentially determined according to the respective priority. A channel having a highest priority is selected from the one or more channels meeting the QoS as a channel for CBP packet transmission. A CBP packet is transmitted via the selected channel.

Abstract: A method for forwarding direct message in partial function OFDMA relay system is proposed in present invention. In present invention, the operations like forwarding and reflecting are fixed for the PFRS. Therefore, the BS performs scheduling according to the fixed operations so as to make the PFRS actually has the function of direct message forwarding.

Abstract: An operating method and apparatus of a Customer Premise Equipment (CPE) in a Cognitive Radio (CR) wireless communication system and a base station in the CR wireless communications system are provided. The method includes, when receiving a beacon message from a Primary User (PU), transmitting a mode change request message including a signal strength from the PU and a channel number interfering with the PU to a base station, when receiving a mode change reply message from the base station, determining whether a partial Frequency Division Duplex (FDD) scheme is applied, and, when the partial FDD scheme is applied, communicating by receiving a downlink burst in a Time Division Duplex (TDD) channel indicated by the mode change reply message and transmitting an uplink burst in an FDD channel indicated by the mode change reply message.

Abstract: A method and apparatus for sychronizing a Quiet Period (QP) in a Cognitive Radio (CR) system includes receiving QP information based on a channel N from at least one neighbor BS. The method further includes determining whether the channel N is an in-band channel. If the channel N is the in-band channel, QP scheduling is performed according to the received QP information based on the channel N.

Abstract: A frequency resource operating apparatus and method for transmitting and receiving data at a different hopping pattern speed according to a CSI in a BWA communication system are provided. In a method of transmitting and receiving data using CSI in a mobile communication system, a BS sets the CSI of an MS to an initial CSI and sends data to the MS according to the initial CSI. The MS sends a downlink CSI to the BS. The BS groups the MS based on the downlink CSI and sends data to the MS according to a hopping pattern for the group of the MS among hopping patterns preset for predetermined groups.

Abstract: An apparatus and method for retransmitting data using an RS in a multi-hop network are provided. When retransmitting data in a BS, the BS transmits data and activates a timer therefor. The BS monitors receipt of a response message for the data until the timer expires. The BS receives the response message and, if it is a Non-Acknowledgement (NACK), determines whether an RS has successfully received the data with a BSN associated with the NACK. If the RS has not successfully received the data, the BS retransmits the data. If the RS has successfully received the data, the BS determines a retransmission entity. If the retransmission entity is the RS, the BS transmits a control message commanding retransmission to the RS, and if the retransmission entity is the BS, the BS retransmits the data.

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: A base station includes an apparatus and a method for exchanging frequency channel resources between base stations in a Cognitive Radio (CR) based communication system. A requesting Base Station (BS), which requests channel exchange a neighboring BS, receives a channel advertisement message from a neighboring BS and sends a channel exchange request message to the neighboring BS. The channel exchange request message includes at least one of a neighbor BS Identifier (ID), a requesting BS ID, channel information for the channel exchange at the requesting BS, and channel information exchangeable at the neighboring BS. The requesting BS receives a channel exchange response message from the neighboring BS in response to the channel exchange request message, determines whether to execute a channel exchange process to the neighboring BS based on information in the received channel exchange response message, and sends a channel exchange reply message indicative of the determination result.

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: An operating method of a source Base Station (BS) for inter-frame sharing in a Cognitive Radio (CR) system includes generating a first random number for a frame contention; requesting the frame contention to one or more destination BSs by carrying the first random number; receiving responses for the frame contention request from the one or more destination BSs; and when positive responses for the frame contention request are received from all of the one or more destination BSs, occupying one or more requested contention frames.

Abstract: A method and apparatus for switching operational modes in a Cognitive Radio (CR) system are provided. A method for switching between a normal operation mode and a coexistence operation mode in a CR system includes occupying at least one channel in the normal operation mode, when there is no channel to be occupied, selecting at least one channel for the coexistence operation mode, and occupying available frames among frames of the selected at least one channel in the coexistence operation mode.

Abstract: A frame structure, a method, and an apparatus for inter-frame resource sharing in a Cognitive Ratio (CR) communication system are provided. An apparatus for sharing a channel in an environment where a plurality of CR communication systems coexist, constitutes a Superframe Control Header (SCH), in one superframe, that includes a frame allocation MAP for frame information allocated to a Base Station (BS), with respect to each BS, and transmits and receives the SCH at the start frame of the frames allocated to the BSs.