Abstract: A ranging method of an access terminal comprising receiving and analyzing UL-MAP/DL-MAP; selecting a given uplink sub-channel number and a symbol number from the UL_MAP when a ranging event is generated; requesting a ranging process by transmitting a CDMA code; receiving a ranging response message broadcasted from the access point; extracting a CDMA code, a sub-channel number, and a symbol number from the received ranging response message, comparing the extracted result and the stored ranging parameters, and adjusting transmission power, timing, and frequency offset on the basis of the extracted result or discarding the ranging response message; and terminating a ranging response message receipt operation.

Abstract: A recording medium having an internal data structure for uplink data transmission based on QoS in a mobile terminal of an OFDMA/TDMA-based high-speed portable Internet system, the internal data structure comprising a connection identifier index indicating a predetermined connection of the mobile terminal; a service class index indicating QoS classes of uplink data; a control channel index indicating a type of a control channel for transmission of a management message of the mobile terminal; an access type index indicating a type of access for a bandwidth request of the mobile terminal; a user packet list having IP packets linked to each other through a linked list; a management message list having the management messages linked to each other through a linked list; and a bandwidth request list having informative elements that are linked to each other for the bandwidth request through a linked list.

Abstract: A ranging method of an access terminal comprising receiving and analyzing UL-MAP/DL-MAP; selecting a given uplink sub-channel number and a symbol number from the UL_MAP when a ranging event is generated; requesting a ranging process by transmitting a CDMA code; receiving a ranging response message broadcasted from the access point; extracting a CDMA code, a sub-channel number, and a symbol number from the received ranging response message, comparing the extracted result and the stored ranging parameters, and adjusting transmission power, timing, and frequency offset on the basis of the extracted result or discarding the ranging response message; and terminating a ranging response message receipt operation.

Abstract: A recording medium having an internal data structure for uplink data transmission based on QoS in a mobile terminal of an OFDMA/TDMA-based high-speed portable Internet system, the internal data structure comprising a connection identifier index indicating a predetermined connection of the mobile terminal; a service class index indicating QoS classes of uplink data; a control channel index indicating a type of a control channel for transmission of a management message of the mobile terminal; an access type index indicating a type of access for a bandwidth request of the mobile terminal; a user packet list having IP packets linked to each other through a linked list; a management message list having the management messages linked to each other through a linked list; and a bandwidth request list having informative elements that are linked to each other for the bandwidth request through a linked list.

Abstract: The advantage of the present invention is to provide a sleep mode driving method for reducing power consumption of a portable terminal in a portable Internet system, and to provide the method for the portable terminal to shift into a sleep mode or an awake mode without loss of transmitting and receiving traffic. The portable terminal transmits a sleep mode request message SLP-REQ to the base station, and receives a sleep mode response message SLP-RSP from the base station, so that it can shift to the sleep mode. The portable terminal receives a traffic indication message TRF-IND from the base station during the sleep mode, and shifts to the awake mode. The portable terminal transmits a wake up information message WKUP-INF informing of a normal operation state, and receives downlink traffic from the base station.

Abstract: A handover reestablishment method capable of effectively re-accessing the serving base station when the mobile terminal fails ranging while moving to the target cell and performs ranging through the handover process, or when the direction of the mobile terminal is changed and thus, the mobile terminal enters into the serving area, is provided. The method includes receiving a handover request message from the mobile terminal; waiting without canceling a connection to the mobile terminal when receiving the handover request message; and performing a reconnection with the mobile terminal when receiving a handover reconnection message from the mobile terminal.

Abstract: In order for a mobile station to manage association of a base station, it is determined whether the base station satisfies Carrier to Interference Noise Ratio (CINR) condition of the mobile station. In addition, a moving probability value of the mobile station into a base station that satisfies the condition is compared with a reference threshold value, and the base station is managed as one of an active set and a semi-active set. Herein, the moving probability value indicates a probability, which is obtained based on a previous moving path of the mobile station into the base station.

Abstract: A channel scanning apparatus in a portable Internet system establishes a radio link with each of neighboring access points without disconnecting a wireless link with a serving access point and collects radio channel state information of each of the respective neighboring access points. That is, apart from a RF signal processing unit that processes a radio signal from the serving access point, the channel scanning apparatus includes a dedicated scanning processing unit for processing a radio signal of a neighboring access point and measuring radio channel state information of the neighboring access point from the radio signals received by the dedicated scanning processing unit, and collects radio channel state information of the respective neighboring access points. In such a way, communication with the serving access point is not disconnected, and therefore the access terminal and the serving access point do not need to buffer traffic data.