摘要:
A method for transmitting data at a high rate in a wireless LAN is provided. A wireless access point requests reliable node information from a wireless terminal having a transfer rate equal to or less than a predetermined transfer rate if data to be transmitted to the terminal occurs. The terminal produces a frame containing information related to reliable nodes that can communicate with the terminal and information of greatest transfer rates between the reliable nodes and the terminal, and transmits the frame to the access point. The access point selects an optimal relay node from the reliable nodes, based on the greatest transfer rates between the reliable nodes and the access point and transfer rates between the reliable nodes and the terminal, and determines if a relay gain exists when using the optimal node. If the relay gain exists, the access point performs relay transmission to the terminal; otherwise, it performs direct transmission to it.
摘要:
A method for transmitting data at a high rate in a wireless LAN is provided. A wireless access point requests reliable node information from a wireless terminal having a transfer rate equal to or less than a predetermined transfer rate if data to be transmitted to the terminal occurs. The terminal produces a frame containing information related to reliable nodes that can communicate with the terminal and information of greatest transfer rates between the reliable nodes and the terminal, and transmits the frame to the access point. The access point selects an optimal relay node from the reliable nodes, based on the greatest transfer rates between the reliable nodes and the access point and transfer rates between the reliable nodes and the terminal, and determines if a relay gain exists when using the optimal node. If the relay gain exists, the access point performs relay transmission to the terminal; otherwise, it performs direct transmission to it.
摘要:
Local communication system in wireless communication system includes a main wireless terminal negotiating with each of the peripheral wireless terminals during a time period for which a frame will be transmitted, generating a schedule map including negotiated time information and a transmission sequence of each of the peripheral wireless terminals, and transmitting the generated schedule map to all peripheral wireless terminals; and the peripheral wireless terminals storing the schedule map received from the main wireless terminal, and performing communication with the main wireless terminal according to the sequence determined in the schedule map for the negotiated time period.
摘要:
A Medium Access Control (MAC) apparatus and method for use in a channel overlay network of a wireless access system. The wireless access system, which is based on a multi-carrier, includes a plurality of physical modules for receiving signals from a plurality of terminals, a plurality of MAC (Medium Access Control) modules for processing the signals received via the physical modules while being classified according to predetermined traffic classes, and a controller connected to the MAC modules for integratedly managing the MAC modules. The MAC apparatus includes an additional MAC module used for a control channel and a plurality of MAC modules for supporting various QoS traffic data according to individual classes, thereby improving scheduling complexity in a MAC layer.
摘要:
A handoff method is provided in a communication network including a plurality of fixed nodes attached to a router connected to at least one external network, and at least one mobile node associated with a current fixed node. The method detects movement of a mobile node; prepares a handoff of the mobile node from a current fixed node to potential fixed nodes upon detecting movement of the mobile node; decides whether to handoff to one of the potential fixed nodes as a target fixed node; and performs the handoff from the current fixed node to the target fixed node. The handoff method enables the mobile station to quickly move its association from one access point to another by minimizing a probe delay which is a primary contributor to handoff delay.
摘要:
Local communication system in wireless communication system includes a main wireless terminal negotiating with each of the peripheral wireless terminals during a time period for which a frame will be transmitted, generating a schedule map including negotiated time information and a transmission sequence of each of the peripheral wireless terminals, and transmitting the generated schedule map to all peripheral wireless terminals; and the peripheral wireless terminals storing the schedule map received from the main wireless terminal, and performing communication with the main wireless terminal according to the sequence determined in the schedule map for the negotiated time period.
摘要:
A handoff method is provided in a communication network including a plurality of fixed nodes attached to a router connected to at least one external network, and at least one mobile node associated with a current fixed node. The method detects movement of a mobile node; prepares a handoff of the mobile node from a current fixed node to potential fixed nodes upon detecting movement of the mobile node; decides whether to handoff to one of the potential fixed nodes as a target fixed node; and performs the handoff from the current fixed node to the target fixed node. The handoff method enables the mobile station to quickly move its association from one access point to another by minimizing a probe delay which is a primary contributor to handoff delay.
摘要:
A Medium Access Control (MAC) apparatus and method for use in a channel overlay network of a wireless access system. The wireless access system, which is based on a multi-carrier, includes a plurality of physical modules for receiving signals from a plurality of terminals, a plurality of MAC (Medium Access Control) modules for processing the signals received via the physical modules while being classified according to predetermined traffic classes, and a controller connected to the MAC modules for integratedly managing the MAC modules. The MAC apparatus includes an additional MAC module used for a control channel and a plurality of MAC modules for supporting various QoS traffic data according to individual classes, thereby improving scheduling complexity in a MAC layer.
摘要:
Provided is a coding/decoding apparatus for an orthogonal frequency division multiple access (OFDMA) communication system that takes multiple users into consideration and uses block coding/decoding scheme. In the apparatus, a mapper determines paths through which information of users will be provided, according to states of sub-channels allocated to the users. A coding/decoding unit parallel-processes the information of the users through the paths selectively connected by the mapper. The coding/decoding unit includes coders/decoders having performance lower than the maximum processing performance determined taking into account a size of a processing block and the number of sub-channels.
摘要:
A method for selecting an antenna in an orthogonalized spatial multiplexing system. Upon receipt of at least one symbol from a transmitter via multiple receive antennas, a receiver decodes each of the received symbols; determines a rotation angle between the received symbols, and selects an optimal subset of transmit antennas using a distance between vectors of the decoded symbols; generates feedback information including the determined rotation angle and the selected optimal subset, and transmits the generated feedback information to the transmitter. Upon receipt of the feedback information, the transmitter beam-forms an antenna corresponding to the optimal subset depending on the received feedback information, and transmits a data symbol to the receiver. The receiver detects each of data symbols received from the transmitter.