Abstract: Disclosed is a system and method for transmitting and receiving hybrid automatic repeat request (HARQ) buffer capability information in a broadband wireless access communication system. According to the system and method, a mobile station detects its own HARQ buffer capacity, and transmits a message including information about the detected HARQ buffer capability to a base station. The base station receives the message and determines the amount of a transmission signal to be allocated to the mobile station based on the HARQ buffer capability, so that it is possible to operate a HARQ scheme in accordance with the HARQ buffer capability of the mobile station.

Abstract: A method for controlling a sleep mode operation by a Mobile Station (MS) in a communication system. The MS includes transitioning to an awake state in a listening interval of the sleep mode; performing any one of a first operation, a second operation and a third operation in the awake state; and after any one operation is performed, transitioning to a sleep state upon detecting that there is no data to transmit to the BS and there is no data to be received from the BS. The first operation is a process of receiving data from the BS, the second operation is a process of transmitting data to the BS, and the third operation is a process of receiving data from the BS and receiving data from the BS.

Abstract: A system is provided for transmitting/receiving downlink resource allocation information in a communication system. In the system, a base station generates first information including downlink resource allocation information necessary for supporting a first mode supported by the base station, generates second information including length information of the first information, and transmits the first information and the second information. A mobile station notifies the base station of a second mode supported by the mobile station, receives, after the notification, the first information and the second information from the base station, and skips without decoding as much downlink resource allocation information as a length corresponding to the length information without decoding, if the first mode is different from the second mode.

Abstract: A system is provided for transmitting/receiving downlink resource allocation information in a communication system. In the system, a base station generates first information including downlink resource allocation information necessary for supporting a first mode supported by the base station, generates second information including length information of the first information, and transmits the first information and the second information. A mobile station notifies the base station of a second mode supported by the mobile station, receives, after the notification, the first information and the second information from the base station, and skips without decoding as much downlink resource allocation information as a length corresponding to the length information without decoding, if the first mode is different from the second mode.

Abstract: Disclosed is a method for selecting transport formats corresponding to transport channels in a wideband code division multiple access mobile communication system.

Abstract: Disclosed are methods for transmitting/receiving a traffic indication message in a wireless communication system. In the wireless communication system, a base station (BS) groups a plurality of sleep mode IDs, and broadcasts a traffic indication message that includes first bitmap information indicating whether traffic corresponding to respective the sleep mode ID groups exists as well as second bitmap information indicating whether traffic indicators with respect to the respective sleep mode IDs that belong to the sleep mode ID groups exists. A mobile subscriber station (MS) which is allocated with any one of the plurality of sleep mode IDs, determines whether the traffic occurs in the sleep mode ID group to which the MS itself belongs using the first bitmap information if the MS receives the traffic indication message, and checks the traffic indicator of the terminal itself using the second bitmap information if the traffic occurs in the sleep mode ID group to which the MS belongs.

Abstract: Disclosed is a system and a method for provisioning service flows in broadband wireless access communication. In a broadband wireless access communication system, if a base station receives a registration request message from a mobile station, and if the base station inserts information about service flows to be provisioned by a base station into a registration response message and transmits the registration response message to the mobile station after the registration request message is received, the mobile station determines if the mobile station transits into a normal operation mode corresponding to the information and exactly recognizes a time point at which the mobile station goes into the normal operation mode.

Abstract: A method for improving the data processing speed in a mobile communication system employing a High Speed Downlink Packet Access (HSDPA) is provided. A data unit for the HSDPA services is produced by inserting a header padding field into a header of the data unit, and transmitting the produced data unit.

Abstract: An apparatus and method for processing handover in a wireless communication system are provided. The method includes selecting a cell for handover when a HandOver (HO) drop occurs, identifying if information for communicating with a serving BS is stored, transmitting a message ranging request signal to the serving BS, identifying provision or non-provision of a service from the serving BS comprised in a response signal to the message ranging request signal, and transmitting/receiving a signal with the serving BS.

Abstract: Disclosed is a system and a method for provisioning service flows in broadband wireless access communication. In a broadband wireless access communication system, if a base station receives a registration request message from a mobile station, and if the base station inserts information about service flows to be provisioned by a base station into a registration response message and transmits the registration response message to the mobile station after the registration request message is received, the mobile station determines if the mobile station transits into a normal operation mode corresponding to the information and exactly recognizes a time point at which the mobile station goes into the normal operation mode.

Abstract: An apparatus and method for estimating UpLink (UL) transmission timing in a Mobile Station (MS) of a wireless communication system are provided. The method includes tracking DL timing by using a DL preamble signal received for each frame; estimating a time offset between a previous frame and a current frame by using the DL timing tracked for each frame; and estimating the UL transmission timing by using the estimated time offset.

Abstract: An apparatus and method for random access in a wireless communication system are provided. In the method, a random access response message is received. The random access response message is analyzed to determine a status of a random access process. A count variable value is updated according to the status. And the count variable value is compared with at least one reference value to determine a random access period. By adaptively changing the period of periodic ranging in a wireless communication system, the probability of success is increased while the waste of resources is decreased.

Abstract: Disclosed is a process for processing an MAC-hs PDU (Protocol Data Unit) in an HSDPA (High Speed Downlink Packet Access) communication system, transmitting at least one PDU (Protocol Data Unit) received over a physical (PHY) layer to an MAC (Media Access Control) layer in an HSDPA (High Speed Downlink Packet Access) communication system, includes an HS-DSCH (High Speed-Downlink Shared Channel) decoder for decoding the PDU at intervals of a first period during which the PDU is received from the PHY layer, and storing the decoded PDU in a first memory; a second memory for storing a control table containing position and number information of the PDU, and performing a reordering queue operation on the basis of the position and number information of the PDU; an HSDPA (High Speed Downlink Packet Access) controller for reading the PDU from the first memory, storing the read PDU in the second memory, monitoring the second memory during a second period which is longer than the first period, updating the number of PDUs

Abstract: A method for processing PDUs (Protocol Data Units) in a receiver, which can receive a PDU to which a TSN (Transmission Sequence Number) is allocated from a transmitter provided in an HSDPA (High-Speed Downlink Packet Access) communication system and store the received PDU in a reordering buffer. A receiver window size associated with the received PDU is set. When a sum of a TSN of the PDU at an upper edge of the receiver window and a value of the set receiver window size is larger than a value of a total TSN size where the TSN of the PDU from the transmitter is outside the receiver window, a corresponding PDU is allowed to be appropriately received if a TSN of the corresponding PDU is within a predetermined range even though the TSN of the corresponding PDU is smaller than the TSN at the upper edge of the receiver window.

Abstract: A method for controlling a sleep-mode operation in a communication system is provided, in which a Mobile Station (MS) transitions to an awake state in a listening interval of the sleep mode, performs one of a first operation, a second operation, and a third operation in the awake state, and transitions to a sleep state if the MS determines that there is no data to transmit to a BS and no data to receive from the Base Station (BS) after the one operation is performed. The first operation is for receiving data from the BS, the second operation is for transmitting data to the BS, and the third operation is receiving data from the BS and transmitting data to the BS.

Abstract: An apparatus and method for updating the location of an idle-mode MS in a communication system are provided, in which the MS transmits a ranging request message requesting location update to a BS, receives a ranging response message from the BS, determines from the ranging response message whether downlink traffic has been generated for the MS, and performs network reentry if downlink traffic has been generated for the MS, and upon receipt of the ranging request message from the MS, the BS performs a location update procedure, determines whether downlink traffic has been generated for the MS, generates the ranging response message including information indicating whether downlink traffic has been generated for the MS, and transmits the ranging response message to the MS.

Abstract: An apparatus and method for detecting channel quality in a mobile communication system are provided. The method includes detecting a channel quality of a first channel quality detection period using a reference value of a reference signal; determining whether a reference value can be measured in a second channel quality detection period being one of a plurality of channel quality detection periods following the first channel quality detection period; and detecting a channel quality of the second channel quality detection period according to the determination.

Abstract: A handover method and apparatus in a communication system are provided. The method includes an MS sending to a serving BS a bandwidth allocating request message for sending a MOB_MSHO-REQ message requesting a handover; activating a timer set to a bandwidth allocation waiting time in relation to the bandwidth allocating request message; stopping the timer upon receipt of a bandwidth allocation message from the serving BS before the timer expires; and determining to perform a handover to a target BS if the MS does not receive the bandwidth allocation message from the serving BS before the timer expires.

Abstract: An apparatus and method for performing a handover in a communication system are provided. For the handover, an MS determines whether a handover process with a serving BS runs normally. If the handover process is abnormal, the MS notifies a target BS of the abnormal handover process and the target BS performs the handover with the MS using handover information corresponding to handover information lost due to the abnormal handover process.

Abstract: In a communication system, a Base Station (BS) transmits a BS diversity set, or the BS diversity set and a BS recommended set to a Mobile Station (MS), and generates a temporary BS diversity set including BSs which are included in the BS diversity set and the BS recommended set, thereby enabling Fast Base Station Switching (FBSS) handover even though diversity set discrepancy between the BS and MS occurs.