Abstract: Provided are a system and method of transmitting an Aggregated Media Access Control (MAC) Protocol Data Unit (A-MPDU) in a Wireless Local Area Network (WLAN) system. A MAC layer divides service data transferred from an upper layer into a plurality of MPDUs, forms a single transmission frame including the sequentially arranged MPDUs, delimiter information for distinguishing each of the MPDUs, and ACK request information for requesting for a reception result of the MPDUs, and transmits the formed transmission frame to a recipient. Accordingly, service coverage is extended, and a transmission delay is minimized, resulting in improved service efficiency.

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: A beamforming method and apparatus for using a rate splitting scheme in a multi-cell multi-antenna system, are provided. The multi-cell multi-antenna system determines transmission and reception beamforming vectors, thereby being divided into a plurality of pairs of single input and single output (SISO) interference channels. A rate splitting scheme may be applied to each of the plurality of pairs.

Abstract: A communication system performs an uplink communication and a downlink communication using respective radio resources that at least partially overlap each other in both time and frequency, which may cause interference to occur in at least one downlink terminal due to at least one uplink terminal. The at least one uplink terminal and the at least one downlink terminal may process the interference according to a rate split scheme, an interference control scheme, and the like. Interference occurring between at least one transmit antenna and at least one receive antenna of a base station may be processed according to an echo cancellation scheme and the like.

Abstract: Provided are a communication apparatus that may generate a precoding matrix including precoding vectors to cancel or align interference existing in a plurality of terminal devices based on location of the terminal devices, and a terminal device that may estimate a channel formed between the terminal device and the communication apparatus to cancel or align interference signals.

Abstract: A power saving apparatus and a method in a wireless communication system are provided. An Access Point (AP) buffers transmission frames for sleep-mode stations in a sleep-mode buffer. Upon wakeup from a sleep mode, a station sends a first control information frame indicating wakeup to the access point. The access point sends a second control information frame including a requested transmission length in response to the first control information frame to the station. The station generates a third control information frame, aggregates the third control information frame and user data frames to a first protocol data unit, and sends it to the AP. Then the AP generates a fourth control information frame, aggregates the fourth control information frame and buffered frames to a second protocol data unit, and sends it to the station.

Abstract: A terminal apparatus for forwarding/sharing a data service is provided. The terminal apparatus for forwarding/sharing the data service includes a service receiver to receive the data service from a service provision apparatus; a connector to perform a connection with a corresponding terminal; and a service forwarding unit to forward the data service to the corresponding terminal via the connection with the corresponding terminal.

Abstract: A terminal location estimation method in a wireless communication system in which an access point (AP) provides an access service to a plurality of terminals includes defining a plurality of beam spaces around the AP through space multiplexing; scheduling the beam spaces according to a predetermined pattern; simultaneously forming a beam in at least one beam space; and detecting the existence and location of a terminal according to whether a response message in response to the formed beam is received. Accordingly, an AP forms beams in a predetermined scheduling pattern, and each of the terminals detecting the beams registers its location by informing the AP that each of the terminals exists in a relevant beam area, and thus, a location of each of the terminals can be estimated without using a complex DOA algorithm.

Abstract: A small cell communication system may reduce interference occurring in a macro terminal through beamforming, even when using the same frequency resources as used by a macro communication system. For example, the small cell communication system may use a larger amount of radio resources than the macro communication system for transmission of feedback information in an uplink. For example, the small cell communication system may use a codebook having a larger size than a size of a codebook used by the macro communication system.

Abstract: A method and apparatus controls power consumption of stations having a hierarchical structure when the stations transmit and receive a wireless signal to and from one another on a CSMA/CA wireless LAN. The controlling involves extracting information on frame transmission speed and transmission period information on first and second layers of the hierarchical structure from the wireless signal; determining a power-controlled period for each of the first and second layers based on the extracted information; and reducing the power consumption of the first and second layers by switching a current mode of the first and second layers to a predetermined mode for the power-controlled period if a reception address included in the extracted information is not identical to an address of the station.

Abstract: Provided is a method, and an apparatus and communication system to perform the method, of detecting a victim terminal and performing an interference coordination in a multi-cell environment. The multi-cell environment may include a heterogeneous cell environment including a small cell and a macro cell. The method includes determining whether a macro terminal is located within a cell coverage of a small base station, and adjusting the cell coverage according to the determination.

Abstract: A communication system with an improved network access structure for inter-cell cooperation is provided. The communication system includes a central unit and at least one radio access unit. The at least one radio access unit may form at least one virtual cell by merging or separating cells of radio access units according to a distribution of terminals, statuses of channels, an amount of traffic, and the like.

Abstract: A roaming service method for a fast and secure wireless network is provided. In an embodiment of the present invention, an AP, which an STA associates with, transmits proactive keys needed for roaming to neighbor APs of the AP. When the STA moves to one of the neighbor APs, a reassociation is carried out between the STA and the neighbor AP using the already provided proactive key. In another embodiment of the present invention, an authentication server transmits proactive keys needed for roaming to neighbor APs to which the STA is likely to move, so that when the STA moves to one of the neighbor APs, a reassociation is carried out between the STA and the neighbor AP using the already provided proactive key.

Abstract: An apparatus and method for controlling transmission rate by determining whether a data transmission failure is caused by a channel error or a data collision in order to reduce a collision-caused rate decrease or a collision-caused rate increase delay in a WLAN. A collision-caused data transmission failure and if the number of data transmission failures reaches a predetermined threshold, data is retransmitted by means of an RTS/CTS exchange.

Abstract: A frequency band setting apparatus and method are provided. The frequency band setting apparatus may include a calculation unit and a control unit. The calculation unit may calculate a basic frequency band of each of a plurality of Access Points (APs), and the control unit may divide a frequency band, which is available to the plurality of APs, into each of the calculated basic frequency bands and a common frequency band.

Abstract: A method for managing a segment threshold includes determining whether a packet has been transmitted to a predetermined terminal, receiving from the predetermined terminal a response message indicating that the predetermined terminal has received the packet without any errors, if a packet has been transmitted to the predetermined terminal, receiving signal intensity data of a current packet transmitted from the predetermined terminal, and adjusting the segment threshold using the received signal intensity data of a current packet, if the response message has been received.

Abstract: A method and apparatus for estimating available throughput of a fixed node in a mobile node of a communication network. The communication network includes fixed nodes connected to a router connected to at least one foreign network and mobile nodes connected to the fixed nodes. A second mobile node is selected from among mobile nodes connected to a fixed node whose available throughput is estimated in a first mobile node. An idle slot interval of the second mobile node connected to the fixed node is set. A transmission probability is measured in one slot interval of the second mobile node through an average of set idle slot intervals. Transmission information of the second mobile node is acquired using the measured transmission probability. The available throughput of the fixed node is estimated using the acquired transmission information.

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: A system to cooperatively control inter-cell interference is provided. A first frequency allocated to a central area of a serving cell associated with a serving base station may be allocated to a central area of a neighboring cell associated with a neighboring base station. A second frequency allocated to an edge area of the serving cell may be allocated to an edge area of the neighboring cell. Where a terminal is located in the edge of the neighboring cell, scheduling information, channel information, and data may be exchanged between the terminal and the serving base station.

Abstract: In a system for sharing hybrid resources in an independent network, each one of a plurality of stations preferably employs a sharing authority transferring protocol that allows the network control function to be moved from station to station depending on the network traffic. Although a distributed coordination method is normally used in the network, when an individual station determines that a real-time data stream is intended for the station, an apparatus having a method and data format for the use thereof allows control to be transferred to the targeted station. This allows the targeted station to control the sharing of the wireless hybrid resources using a centralized control method in a direct mode for the duration of the real-time service transmission, thereby optimizing network efficiency. As a result of using the distributed control authority of the present invention, a station may be freely subscribe/withdraw to/from the network.