Abstract: A system and method for performing a handover operation in a broadband wireless access (BWA) communication system. The BWA communication system includes a serving BS (Base Station), (Subscriber Station), and a plurality of neighbor BSs adjacent to the serving BS. The SS handover method upon receiving a handover request from the SS in the BWA communication system includes the steps of: a) receiving from the serving BS information of the plurality of neighbor BSs; b) measuring CINRs (Carrier to Interference and Noise Ratios) of pilot signals transferred from the neighbor BSs upon receipt of the neighbor BSs information; c) transmitting to the serving BS a handover request signal along with pilot signal CINR information of the neighbor BSs; d) upon receipt of the handover request signal, receiving from the serving BS information of a handover enable target BS contained in the neighbor BSs; and e) performing a handover function from the serving BS to the target BS.

Abstract: An apparatus and method for controlling a reverse data rate in a mobile station. The method including determining a bit of a multi-bit control channel information based on at least two of a current data rate, transmission power, and an amount of data stored in a buffer of the mobile station; and transmitting the multi-bit control channel information to a base station. The bit of the multi-bit control channel information is determined based on whether the mobile station has power available to transmit at a higher reverse data rate.

Abstract: An apparatus in a Base station (BS) and an apparatus in a Mobile Station (MS) are provided for allocating and requesting, respectively, uplink resources in a wireless communication system. The apparatus in the MS includes a transmitter for sending, to a base station, a predetermined Channel Quality Information CHannel (CQICH) codeword over a pre-allocated CQICH in a silence period, when an uplink bandwidth for an extended real-time Polling Service (ertPS) is not allocated to the mobile station, to inform the base station that the mobile station has data to send; and a receiver for receiving, from the base station, information related to an uplink bandwidth supporting a maximum rate allocated by the base station, in response to the CQICH codeword.

Abstract: An apparatus and method for controlling a reverse data rate in a mobile station. The method including determining a bit of a multi-bit control channel information based on at least two of a current data rate, transmission power, and an amount of data stored in a buffer of the mobile station; and transmitting the multi-bit control channel information to a base station. The bit of the multi-bit control channel information is determined based on whether the mobile station has power available to transmit at a higher reverse data rate.

Abstract: An apparatus and method for controlling a reverse data rate in a mobile station. The method includes determining whether the mobile station has sufficient power to transmit at an increased data rate compared to a current data rate, and transmitting a determination result to a base station.

Abstract: A Mobile Subscriber Station (MSS) and an active Base Station (BS) for measuring/reporting a channel quality in a broadband wireless access communication system. The MSS includes a receiver for receiving, from an active BS, channel quality measurement information for the MSS to measure channel qualities of the active BS and a plurality of neighbor BSs, and channel quality report information defining a report mode for the MSS to report measured channel qualities of the active BS and the plurality of neighbor BSs, a processor for measuring the channel qualities of the active BS and the plurality of neighbor BSs according to the channel quality measurement information, and a transmitter for reporting the measured channel qualities of the active BS and the plurality of neighbor BSs to the active BS according to the channel quality report information.

Abstract: A method for requesting allocation of a Channel Quality Information Channel (CQICH) by a Mobile Station (MS) in a communication system. The method includes switching, by the MS, from a serving anchor Base Station (BS) to a target anchor BS, detecting an absence of a CQICH allocated from the target anchor BS, and transmitting, from the MS to the target anchor BS, a CQICH allocation request. The CQICH allocation request includes a CQICH allocation request header including a basic Connection IDentifier (CID) of the MS and a Header Check Sequence (HCS) for the CQICH allocation request header.

Abstract: Methods and apparatus are provided for performing a handover by a serving base station in a communication system. A handover request message is received from a mobile station. A first handover response message is transmitted to the mobile station. The first handover response message includes a list of at least one neighbor base station. A handover indication message including a value of a handover indication type field is received. The value is determined by the mobile station from among at least two values individually indicating at least one of a handover cancel and the handover rejection. The value representing the handover cancel indicates that the mobile station intends to cancel a handover procedure, and the value representing the handover rejection indicates that the mobile station intends to reject performing handover with any of the at least one neighbor base stations in the list.

Abstract: The present invention relates to a method for performing a ranging operation according to the priority order in a mobile communication system using a BWA (Broadcast Wireless Access) scheme. The method according to the invention for performing a range operation by a subscriber terminal in a mobile communication system using the BWA (Broadcast Wireless Access) scheme comprises steps of: receiving backoff domains having the start and end values of the backoff corresponding to each ranging operation, the backoff domains being determined from a base station according to the priority order of the ranging operations between the base station and subscriber terminals; performing a ranging operation and, if it is determined that the step of performing the ranging operation fails, selecting backoff domains among the received backoff domains according to the priority order of the performed ranging operations; and, re-performing the ranging operation according to the selected backoff domains.

Abstract: An apparatus in a Base station (BS) and an apparatus in a Mobile Station (MS) are provided for allocating and requesting, respectively, uplink resources in a wireless communication system.

Abstract: Provided is a device and method for scheduling uplink resources in a wireless communication system supporting VoIP. When its data rate is decreased, an MS notifies a BS of the rate decreased. When increasing its data rate, the MS requests resource allocation to the BS by transmitting a BR header or a CQICH codeword. Compared to the conventional ertPS in which the BS periodically allocates uplink resources to the MS irrespective of the state of the MS, the BS does not allocate uplink resources when the MS transitions form a talk-spurt period to a silence period. Therefore, resources consumption arising from unnecessary bandwidth allocation is reduced.

Abstract: Methods and apparatus are provided for performing a handover by a serving base station in a communication system. A handover request message is received from a mobile station. A first handover response message is transmitted to the mobile station. The first handover response message includes a list of at least one neighbor base station. A handover indication message including a value of a handover indication type field is received. The value is determined by the mobile station from among at least two values individually indicating at least one of a handover cancel and the handover rejection. The value representing the handover cancel indicates that the mobile station intends to cancel a handover procedure, and the value representing the handover rejection indicates that the mobile station intends to reject performing handover with any of the at least one neighbor base stations in the list.

Abstract: Disclosed is a system and a method for controlling a handover of a mobile subscriber station in a broadband wireless access communication system. When serving base station determines to perform a handover of the mobile subscriber station, neighbor base stations to which the mobile subscriber station can be handed over, from among neighbor base stations of the mobile subscriber station, are determined based on a service quality level of service being currently provided to the mobile subscriber station. A handover request signal containing information related to the determined neighbor base station to which the mobile subscriber station can be handed over is transmitted to the mobile subscriber station.

Abstract: Disclosed is a method for enabling a mobile station existing in a serving cell area to perform a handover procedure in a broadband mobile communication system including the mobile station, a serving base station providing a service to the mobile station, and one or more target base stations containing at least one target cell area overlapping with the serving cell area occupied by the serving base station. The method includes transmitting a handover request message from the mobile station to the serving base station when it is detected that a performance of a handover is necessary; and transmitting a handover indication message containing handover cancel information to the serving base station when the mobile station determines a cancel of the handover while the mobile station is being handed over to one or more target base stations by the serving base station.

Abstract: Disclosed is a system and a method for controlling a handover of a mobile subscriber station in a broadband wireless access communication system. When serving base station determines to perform a handover of the mobile subscriber station, neighbor base stations to which the mobile subscriber station can be handed over, from among neighbor base stations of the mobile subscriber station, are determined based on a service quality level of service being currently provided to the mobile subscriber station. A handover request signal containing information related to the determined neighbor base station to which the mobile subscriber station can be handed over is transmitted to the mobile subscriber station.

Abstract: Disclosed is a system and a method for controlling a handover of a mobile subscriber station in a broadband wireless access communication system. When serving base station determines to perform a handover of the mobile subscriber station, neighbor base stations to which the mobile subscriber station can be handed over, from among neighbor base stations of the mobile subscriber station, are determined based on a service quality level of service being currently provided to the mobile subscriber station. A handover request signal containing information related to the determined neighbor base station to which the mobile subscriber station can be handed over is transmitted to the mobile subscriber station.

Abstract: A Mobile Subscriber Station (MSS) and an active Base Station (BS) for measuring/reporting a channel quality in a broadband wireless access communication system. The MSS includes a receiver for receiving, from an active BS, channel quality measurement information for the MSS to measure channel qualities of the active BS and a plurality of neighbor BSs, and channel quality report information defining a report mode for the MSS to report measured channel qualities of the active BS and the plurality of neighbor BSs, a processor for measuring the channel qualities of the active BS and the plurality of neighbor BSs according to the channel quality measurement information, and a transmitter for reporting the measured channel qualities of the active BS and the plurality of neighbor BSs to the active BS according to the channel quality report information.

Abstract: A method for measuring/reporting a channel quality in a broadband wireless access communication system. The method for reporting channel qualities of active BS and neighbor BSs measured by an MSS to the active BS when the MSS exists in a specific area covered by the active BS and neighbor BSs in a communication system includes receiving channel quality report information indicative of channel periods of the channel qualities from the active BS, and receiving channel quality measurement information associated with individual channel qualities of the neighbor BSs and the active BS from the active BS: measuring SINRs of the neighbor BSs and the active BS according to the channel quality measurement information; and reporting the measured SINRs of the neighbor BSs and the active BS to the active BS.

Abstract: A broadband wireless access (BWA) communication system includes a mobile subscriber station (MSS), a serving base station (BS) with which the MSS performs communication, and a plurality of neighbor BSs. The serving BS transmits, to the MSS, a handover request message including information on at least one recommended BS to which the MSS can perform a handover, among the neighbor BSs, and indication information indicating a fast handover, and transmits, to each of the recommended BSs, a handover confirm message indicating that the MSS will perform the fast handover.

Abstract: A method for measuring/reporting a channel quality in a broadband wireless access communication system. The method for reporting channel qualities of active BS and neighbor BSs measured by an MSS to the active BS when the MSS exists in a specific area covered by the active BS and neighbor BSs in a communication system includes the steps of: a) receiving channel quality report information indicative of channel periods of the channel qualities from the active BS, and receiving channel quality measurement information associated with individual channel qualities of the neighbor BSs and the active BS from the active BS; b) measuring SINRs of the neighbor BSs and the active BS according to the channel quality measurement information; and c) reporting the measured SINRs of the neighbor BSs and the active BS to the active BS.