Abstract: A reliable multicast data retransmission method by grouping wireless terminals in a wireless communication environment and performing multicast data retransmission for a particular group of wireless terminals that needs multicast data retransmission, thereby providing reliable multicast data retransmission and improving the efficiency of a network. The multicast data retransmission method includes grouping wireless terminals based on distances between an access point and the wireless terminals and the amplitudes of signals output from the wireless terminals, selecting a repeater, which is to retransmit multicast packets, from each group and arranging the order in which repeaters retransmit multicast packets, creating a multicast packet train header indicating characteristics of each of the multicast packets, multicasting the created multicast packet train header. The multicast packets are retransmitted in the arranged order.

Abstract: A method for generating packet-based transmission control parameters includes (a) receiving class information of an audio-video (AV) application and characteristic information of an AV packet, from the AV application, (b) receiving status information of a wireless channel and buffer storage time information of the AV packet, from a medium access control (MAC) layer, and (c) generating and outputting the packet-based transmission control parameters on the basis of the received information. In addition, a selective retransmission method includes (a) transmitting packets of an MPEG-2 frame in real-time, (b) checking for any transmission error after the transmission, and (c) if any transmission error is generated, retransmitting only packets of an I-frame. Therefore, it is possible to efficiently support AV service in wireless communication by dynamically controlling transmission control parameters according to a buffer status and by reflecting the characteristics of the AV frames.

Abstract: A data transceiver and a data reception method for reducing power consumption in a mobile communication system are provided. The data transceiver includes a transmitter which transmits a plurality of data frames during a predetermined transmission period; and a receiver which receives data frames in the predetermined transmission period, if the transmission period is allowed and monitors with minimal operation power whether data transmission is in progress or completed in the transmission period, if the transmission period is not allowed.

Abstract: Disclosed is a method for detecting a hidden station in a specific station constituting a wireless communication network that includes receiving a frame after a lapse of an idle state interval longer than a predetermined waiting time; determining that there is a hidden station, if a size of the received frame is equal to a size of an Acknowledge (ACK) frame; and determining that there is no hidden station, if the size of the received frame is not equal to the size of the ACK frame.

Abstract: An apparatus is provided for allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period and an uplink period allocated to each station (STA), and at least one sub PSMP frame indicating an allocated downlink period for at least one of a retransmission of downlink data and a transmission of an ACK indicating successful receipt of uplink data. After exchanging data with the AP in the downlink and uplink periods indicated by the PSMP frame, an STA receives the each sub PSMP frame, and performs at least one of a reception of the retransmitted downlink data and a reception of the ACK in the downlink period indicated by the each sub MAP frame.

Abstract: A method is provided for efficiently allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period provided to each station (STA) and a minimum amount of an uplink period allocated to each STA, and at least one sub PSMP frame indicating an uplink period additionally provided for an STA that transmitted a resource request message for remaining queued data in the uplink period indicated by the PSMP frame. If the uplink period indicated by the PSMP frame is insufficient to transmit the queued data, the STA transmits a data unit including a part of the queued data and a resource request message for the remaining queued data in the uplink period. After transmitting the resource request message, the STA receives the sub PSMP frame after the full period indicated by the sub PSMP frame, and transmits the remaining queued data to the AP in the uplink period indicted by the sub PSMP frame.

Abstract: An apparatus is provided for efficiently allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period provided to each station (STA) and a minimum amount of an uplink period allocated to each STA, and at least one sub PSMP frame indicating an uplink period additionally provided for an STA that transmitted a resource request message for remaining queued data in the uplink period indicated by the PSMP frame. If the uplink period indicated by the PSMP frame is insufficient to transmit the queued data, the STA transmits a data unit including a part of the queued data and a resource request message for the remaining queued data in the uplink period. After transmitting the resource request message, the STA receives the sub PSMP frame after the full period indicated by the sub PSMP frame, and transmits the remaining queued data to the AP in the uplink period indicted by the sub PSMP frame.

Abstract: A method is provided for allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period and an uplink period allocated to each station (STA), and at least one sub PSMP frame indicating an allocated downlink period for at least one of a retransmission of downlink data and a transmission of an ACK indicating successful receipt of uplink data. After exchanging data with the. AP in the downlink and uplink periods indicated by the PSMP frame, an STA receives the each sub PSMP frame, and performs at least one of a reception of the retransmitted downlink data and a reception of the ACK in the downlink period indicated by the each sub MAP frame.

Abstract: A system is provided for allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period and an uplink period allocated to each station (STA), and at least one sub PSMP frame indicating an allocated downlink period for at least one of a retransmission of downlink data and a transmission of an ACK indicating successful receipt of uplink data. After exchanging data with the AP in the downlink and uplink periods indicated by the PSMP frame, an STA receives the each sub PSMP frame, and performs at least one of a reception of the retransmitted downlink data and a reception of the ACK in the downlink period indicated by the each sub MAP frame.

Abstract: A system is provided for efficiently allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period provided to each station (STA) and a minimum amount of an uplink period allocated to each STA, and at least one sub PSMP frame indicating an uplink period additionally provided for an STA that transmitted a resource request message for remaining queued data in the uplink period indicated by the PSMP frame. If the uplink period indicated by the PSMP frame is insufficient to transmit the queued data, the STA transmits a data unit including a part of the queued data and a resource request message for the remaining queued data in the uplink period. After transmitting the resource request message, the STA receives the sub PSMP frame after the full period indicated by the sub PSMP frame, and transmits the remaining queued data to the AP in the uplink period indicted by the sub PSMP frame.

Abstract: A method is provided for efficiently allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period provided to each station (STA) and a minimum amount of an uplink period allocated to each STA, and at least one sub PSMP frame indicating an uplink period additionally provided for an STA that transmitted a resource request message for remaining queued data in the uplink period indicated by the PSMP frame. If the uplink period indicated by the PSMP frame is insufficient to transmit the queued data, the STA transmits a data unit including a part of the queued data and a resource request message for the remaining queued data in the uplink period. After transmitting the resource request message, the STA receives the sub PSMP frame after the full period indicated by the sub PSMP frame, and transmits the remaining queued data to the AP in the uplink period indicted by the sub PSMP frame.

Abstract: A system is provided for efficiently allocating a transmission period in a WLAN system. An access point (AP) transmits a PSMP message providing a downlink period and an uplink period provided to each station (STA), and at least one sub PSMP frame indicating a period of at least one of a downlink and an uplink for an STA requiring additional resource allocation. After exchanging data with the AP in the downlink and uplink periods provided by the PSMP frame, if there is a need for additional resource allocation, the STA receives the at least one sub PSMP frame and exchanges data with the AP in the period provided by the each sub PSMP frame.

Abstract: A method is provided for efficiently allocating a transmission period in a WLAN system. An access point (AP) transmits a PSMP message providing a downlink period and an uplink period provided to each station (STA), and at least one sub PSMP frame indicating a period of at least one of a downlink and an uplink for an STA requiring additional resource allocation. After exchanging data with the AP in the downlink and uplink periods provided by the PSMP frame, if there is a need for additional resource allocation, the STA receives the at least one sub PSMP frame and exchanges data with the AP in the period provided by the each sub PSMP frame.

Abstract: An apparatus is provided for allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period and an uplink period allocated to each station (STA), and at least one sub PSMP frame indicating an allocated downlink period for at least one of a retransmission of downlink data and a transmission of an ACK indicating successful receipt of uplink data. After exchanging data with the AP in the downlink and uplink periods indicated by the PSMP frame, an STA receives the each sub PSMP frame, and performs at least one of a reception of the retransmitted downlink data and a reception of the ACK in the downlink period indicated by the each sub MAP frame.

Abstract: An apparatus is provided for efficiently allocating a transmission period in a WLAN system. An access point (AP) transmits a PSMP message providing a downlink period and an uplink period provided to each station (STA), and at least one sub PSMP frame indicating a period of at least one of a downlink and an uplink for an STA requiring additional resource allocation. After exchanging data with the AP in the downlink and uplink periods provided by the PSMP frame, if there is a need for additional resource allocation, the STA receives the at least one sub PSMP frame and exchanges data with the AP in the period provided by the each sub PSMP frame.

Abstract: A method is provided for efficiently allocating a transmission period in a WLAN system. An access point (AP) transmits a PSMP message providing a downlink period and an uplink period provided to each station (STA), and at least one sub PSMP frame indicating a period of at least one of a downlink and an uplink for an STA requiring additional resource allocation. After exchanging data with the AP in the downlink and uplink periods provided by the PSMP frame, if there is a need for additional resource allocation, the STA receives the at least one sub PSMP frame and exchanges data with the AP in the period provided by the each sub PSMP frame.

Abstract: An apparatus is provided for efficiently allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period provided to each station (STA) and a minimum amount of an uplink period allocated to each STA, and at least one sub PSMP frame indicating an uplink period additionally provided for an STA that transmitted a resource request message for remaining queued data in the uplink period indicated by the PSMP frame. If the uplink period indicated by the PSMP frame is insufficient to transmit the queued data, the STA transmits a data unit including a part of the queued data and a resource request message for the remaining queued data in the uplink period. After transmitting the resource request message, the STA receives the sub PSMP frame after the full period indicated by the sub PSMP frame, and transmits the remaining queued data to the AP in the uplink period indicted by the sub PSMP frame.

Abstract: An apparatus and method is provided for efficiently allocating a transmission period in a WLAN system. An access point (AP) transmits a PSMP message providing a downlink period and an uplink period provided to each station (STA), and at least one sub PSMP frame indicating a period of at least one of a downlink and an uplink for an STA requiring additional resource allocation. After exchanging data with the AP in the downlink and uplink periods provided by the PSMP frame, if there is a need for additional resource allocation, the STA receives the at least one sub PSMP frame and exchanges data with the AP in the period provided by the each sub PSMP frame.

Abstract: A method is provided for allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period and an uplink period allocated to each station (STA), and at least one sub PSMP frame indicating an allocated downlink period for at least one of a retransmission of downlink data and a transmission of an ACK indicating successful receipt of uplink data. After exchanging data with the AP in the downlink and uplink periods indicated by the PSMP frame, an STA receives the each sub PSMP frame, and performs at least one of a reception of the retransmitted downlink data and a reception of the ACK in the downlink period indicated by the each sub MAP frame.

Abstract: Disclosed is a method and an apparatus for self-calibrating direct current (DC) offset and imbalance between orthogonal signals, which may occur in a mobile transceiver. In the apparatus, a transmitter of a mobile terminal functions as a signal generator, and a receiver of the mobile terminal functions as a response characteristic detector. Further, a baseband processor applies test signals to the transmitter, receives the test signals returning from the receiver, and compensates the imbalance and DC offset for the transmitter side and the receiver side by using the test signals.