Abstract:
An apparatus and a method for transmitting and receiving data in a communication system prevent unnecessary operation of a receiver by informing the receiver of non-existence of data to be transmitted. An identifier expressing the transmission data change information is set up as the arbitrary value and is transmitted to the mobile terminal(205). A negative acknowledgement message is received from the mobile terminal(215). The transmission data change information set up as described If the negative acknowledgement message is received over a predetermined frequency set up in advance, non-existence of the transmission data is shown by maintaining the identifier value expressing the preset transmission data change information and transmitting the identifier value to the mobile terminal.
Abstract:
An apparatus and a method for data retransmission in a wireless communication system using a multi hop relay are provided to transmit a multi control message for ARQ(Automatic Retransmission reQuest). According to an operation method of a relay station(202,204) in a wireless communication system using multi hop relay, the error generation of data received from an upper node is checked. When a message indicating the error generation from lower nodes is received, the message for the error generation of the data and the message for the error generation from the lower nodes are transmitted to the upper node. The upper node is a base station(200) or an upper relay station. The error of the data is checked by CRC(Cyclic Redundancy Check).
Abstract:
An apparatus and a method for transmitting an asynchronous control message for data retransmission in a wireless communication system using relay are provided to perform the asynchronous data retransmission in the wireless communication system by using multi-hop relay, thereby reducing a delayed retransmission time generated in synchronous data retransmission. A BS(Base Station)(600) transmits data to a RS1(Relay Station)(610) in an i frame. The RS1 checks whether an error occurs on the data. The RS1 transmits an asynchronous NACK(Negative Acknowlegment) message for requesting data retransmission to the BS in an (i+1) frame. The BS retransmits the data transmitted from the RS1 in the i frame to the RS1 in an (i+2) frame.
Abstract:
본 발명은 통신 시스템에서, 이동 단말기가 슬립 모드로 동작하는 중에 기지국과 주기적 레인징을 수행하기 위해 어웨이크 모드로 천이하고, 상기 어웨이크 모드로 천이한 시점부터 제1설정 시간 동안 상기 주기적 레인징 수행을 위해 필요한 업링크 자원이 할당되었는지 검사하고, 상기 검사 결과 상기 업링크 자원이 할당되지 않았을 경우 상기 주기적 레인징 수행에 실패하였음으로 판단하고, 상기 업링크 자원이 할당되지 않아 주기적 레인징 수행에 실패함에 따라 상기 기지국과의 통신 상태를 비정상적인 상태로 판단한다. 주기적 레인징, 업링크 자원, 주기적 레인징 실패, 비정상 상태
Abstract:
An apparatus and a method for executing handover in a broadband wireless communication system are provided to enable MAC(Media Access Control) addresses of an MS(Mobile Station), which executes multiple FA(Frequency Allocation) communication, to respectively access different FAs of an identical cell in case the MS executes handover. An MS, which supports multi-FA communication in a broadband wireless communication system, comprises a multiple FA controller(700), a first MAC processor(710), and a second MAC processor(720). The multiple FA controller controls the MAC processors so as to perform handover to different FAs of an identical base station respectively. The MAC processors have their respective MAC addresses. In case handover is determined, the first MAC processor generates handover start information to the multi-FA controller, and accesses an FA of a base station. Under the control of the multi-FA controller, the second MAC processor determines a target for handover in order to access another FA of the base station.
Abstract:
An apparatus and a method for control message transmission in a wireless communication system using a relay are provided to reduce a waste of radio resources by transmitting only signals without errors to a base station from a relay station. A method for uplink signal retransmission in a wireless communication system using a relay includes the steps of: checking a message indicating an error of a terminal uplink signal received from a relay station when receiving the terminal uplink signal from the relay station; transmitting scheduling information about the terminal uplink signal to the relay station when the terminal uplink signal does not have the error(401); checking an error of data when receiving the data from the relay station(411); and requesting retransmission of the data to the relay station when the data has the error(417).
Abstract:
An apparatus and a method for supporting non-contention-based ranging in a multi-hop relay broadband wireless access communication system are provided to allow a lower node of a relay station to receive a communication service continuously. When a non-contention-based ranging interval needs to be allocated to a relay station, a base station exchanges information required for the allocation of the non-contention-based ranging interval with a corresponding upper relay station(401). The upper relay station uses the information required for allocation of the ranging interval for scheduling and configures resource allocation information according to the scheduling result(403). The relay station transmits a MAP message with the non-contention-based ranging interval information to a lower at a predetermined time point(405). The relay station obtains synchronization of the upper relay station(407) and analyzes the received MAP message to obtain the non-contention-based ranging interval information allocated thereto. The relay station transmits a ranging message through the allocated non-contention-based ranging interval(409). The relay station exchanges a message required for a network re-entry procedure with the upper relay station and the base station(411).
Abstract:
A system and a method for controlling a sleep mode operation in a communication system are provided to reduce power consumption by controlling a sleep mode operation between an MS(Mobile Station) and a BS(Base Station) by adaptively operating a neutral section. An MS enters from a listening section from a sleep section and is in standby(301). The MS receives a TRF-IND(Traffic Indication) message from a BS and decodes it(303). The MS checks whether the TRF-IND message includes its identifier(305). If the TRF-IND message includes an identifier of the MS, the MS transmits/receives data to/from the BS(309). If the TRF-IND message does not include the identifier of the MS, the MS checks an uplink buffer and checks whether it has data to be transmitted to the BS(307). If there is data to be transmitted, the MS transmits the data to the BS(309). While data transmission/reception is performed between the MS and the BS, the MS checks whether a neutral section has been terminated(311). If the neutral section has been terminated, the MS transitions to a sleep state(313).
Abstract:
An apparatus and a method for configuring an R-FCH(Relay Station Frame Control Header) in a BWA communication system which uses a multihop relay scheme are provided to determine a modulation scheme in consideration of the channel state between an RS and a BS(Base Station), variably apply the modulation scheme according to the channel state, and efficiently use resources by configuring an R-FCH containing information necessary to decode RS DL-MAP information and providing a message which indicates a MAP modulation scheme to decode the RS DL-MAP information. An RS(Relay Station)(410) executes an initial network entry procedure with a BS(411). In this case, the initial network entry procedure is executed at the first sections of a BS frame. The BS transmits a DCD message to the RS(413). Receiving the DCD(Downlink Channel Descriptor) message, the RS acquires DIUC(Downlink Interval Usage Code) information(415). The BS monitors the channel state with the RS while executing the initial network entry procedure(417). Then the BS determines a modulation scheme and an encoding scheme for RS DL-MAP information, based on a monitoring result(419). After finalizing the initial network entry procedure, the RS and the BS execute communication to provide a relay service to an MS(Mobile Station) at the second sections of the BS frame(421). The BS configures an R-FCH which will be transmitted at the very first of the second section of the DL subframe of the BS frame and transmits it to the RS(423,425). In this case, the R-FCH contains the determined RS DL-MAP encoding information. Receiving the R-FCH, the RS acquires information necessary to decode the RS DL-MAP information(427).
Abstract:
An apparatus and a method for supporting a relay service in a broadband wireless communication system by using a multi-hop relay manner are provided to transmit the transmission and reception transition time from an upper relay station to a lower relay station. Transmission and reception area information of a lower relay station is confirmed. A process for transmitting the transmission and reception mode change area information and a signal for a terminal is performed during the first period(311) of a down-link sub frame according to the resource allocation information. A process for transmitting a signal for the lower relay station is performed during the second period(313) of the down-link sub frame(310). The transmission and reception mode change area information includes time information for changing the operation of the lower relay station at the down-link sub frame and the up-link sub frame(320). The transmission and reception mode change area information also includes overhead information of the up-link and down-link sub frames.