Samsung Electronics Co., Ltd.

Seoul National University

University System of Maryland

Tsinghua University

Korea Advanced Institute of Science and Technology

Korea University Industrial Academic Collaboration Foundation

Kyung-Hun Jang

Young-Soo Kim

Hyo-Sun Hwang

Dong-jun Lee

Jong-Ae Park

Jung-Hoon Suh

Jin-Bong Chang

Chang-Woo Seo

Jin-Youn Cho

Sunghyun Choi

In-Sun Lee

Sung-hyun Choi

Min-Ho Shin

William Albert Arbaugh

Arunesh Mishra

Tae-Jin Lee

Youngsoo Kim

Sung-Jea Ko

Zhigang Cao

Choong-hun Lee

Yongxing Zhou

Yung-Soo Kim

Jongseok Kim

Dong-Ho Cho

Ki-Ho Lee

Ok-Seon Lee

Dong-Jun Lee

Jianjun Li

Jong-Ho Park

Sung-Geun Jin

Sang-Hyun Woo

Jong-ho Park

Heun-Chul Lee

Pil-Yong Hwang

Sung-Hyun Choi

Yong-Xing Zhou

Tae-Soo Kwon

In-Kyu Lee

Jun-Seok Park

Ae-Ri Lim

Seongkwan Kim

Kwang-Hun Han

Yoong-Soo Kim

Hye-Soo Kim

Chun-su Park

Hyun-II Kang

Ki-Hyun Pyun

Alexey Sidelnikov

Gang-Youl Yu

Jin-bong Chang

Junfeng Jiang

Pingyi Fan

Pinyi Fan

Shufu Mao

Jin-Bong Cahng

Hyun-Ki Ahn

Duck-Yong Yang

Kyung-Ho Hwang

Sung-Hyun Seoul Nat Univ Ind Foundation Choi

An apparatus and method for transmitting packets in a communication system. The packet transmission method for the communication system includes the steps of a) receiving Quality of Service (QoS) information and data rate information from an upper layer, b) receiving channel status information of wireless stations from a lower layer, and c) creating an aggregation packet according to the received information, and transmitting the created aggregation packet to a Media Access Control (MAC) layer.

Apparatus and method for transmitting packets in a communication system

In the data transmission method, a MAC layer receives data from an upper layer, classifies the data according to destination addresses and traffic identifiers, aggregates the data by destination address and traffic identifier as a first transmission unit, aggregates the first transmission units having the identical destination address as a second transmission unit, and transmits the second transmission units having different destination addresses in a single frame. The data transmission method allows packets transferred from the upper layer to be hierarchically aggregated by DAs and TIDs and then packaged into a data unit for each destination such that it is possible to transmit the data at an optimal data rate for each destination terminal.

Data transmission method using packet aggregation

A method for minimizing handoff latencies when a handoff is performed in a wireless network. An access point (AP) or base station associated to a current wireless station (STA) allows information required for a reassociation to the STA to be propagated to handoff-capable neighboring APs or base stations. When the STA moves, a neighboring AP or base station performs the reassociation to the STA on the basis of context. When a handoff procedure is performed, the time taken to receive context of a corresponding STA is reduced, such that a fast handoff can be implemented.

Method for performing handoff in wireless network

The present invention relates to a power saving in a wireless local area network including a plurality of access points providing at least one mobile station in each access point cell boundary with access service, the mobile station transits between an active mode and an idle mode. The power saving method includes grouping the access points into at least one paging group with a paging group boundary; determining if the a mobile station is in the idle mode in which the mobile station switches between an awake state and a doze state every predetermined time interval, or the active mode in which the mobile station is in the awake mode; and if the mobile station is in the idle mode enabling an idle handoff which occurs only when the mobile station crosses the paging group boundary. In the present invention, the handoff occurs when the mobile terminal crosses the paging group boundary but not the access point cell in the idle mode, resulting in reduction of power consumption.

Power saving method for mobile terminal in wireless local area network

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.

Method for detecting hidden station in a wireless communication network and system therefor

A wireless communication system including transmitters for determining a transmission rate for an associated receiver according to channel state information fed back from associated receivers, and transmitting packets at the determined transmission rate. In a communication method, a transmitter groups packets to be transmitted to the receivers according to transmission rates, and generates frames configured by packets with an identical transmission rate. The transmitter aggregates frames with different transmission rates into one transmission burst, and sends the transmission burst. The data communication method based on packet aggregation can efficiently manage resources by determining transmission rates for reception stations (STAs) on the basis of feedback channel state information in a transmission STA, aggregating packets to be transmitted to the reception STAs to form a packet group, and transmitting packet groups with different transmission rates using one multi-rate aggregation (MRA) burst.

Data communication method based on multi-receiver aggregation

Disclosed is a receiver for configuring a Block Acknowledgement (BA) frame in a wireless communication system for acknowledgement of a data transmission from a transmitter. The receiver receives a Block Acknowledgement Request (BAR) frame in the data transmission from the transmitter and determines an overall size of a bitmap for the BA frame from the BAR frame to acknowledge the data transmission. The receiver configures the BA frame of the response to include the bitmap having the determined overall size, and transmits the configured BA frame to the transmitter. The bitmap of the BA frame includes bits representing reception results of packets of the data transmission received from the transmitter.

Apparatus for reporting reception result of packets in mobile communication system

Disclosed is a method for configuring a bitmap in a mobile communication system employing a block ACK scheme, which faithfully performs its intrinsic function of acknowledging a reception result, and yet can reduce transmission delay and the overall system load due to retransmission in the case where packet loss is relatively less important than transmission delay time, such as in the case of voice communication. To this end, a recipient compares a PER of a received packet signal with a threshold value. If the PER is higher than the threshold value, the recipient operates in the block ACK scheme, and if the PER is lower than the threshold value, the recipient determines a bitmap configuration scheme on the assumption that an erroneous frame has been successfully received. Also, using the determined bitmap configuration scheme, the recipient transmits a reception result for each received packet.

Method for reporting reception result of packets in mobile communication system

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.

Apparatus and method for selecting antenna in an orthogonalized spatial multiplexing system

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.

Method for allocating transmission period in a wireless communication system

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.

Method of transmitting aggregated MAC MPDUs in WLAN system and system therefor

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.

Method for sharing hybrid resources in a wireless independent network, a station for the method, and a data format for the method and the station

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.

Power saving apparatus and method in a wireless communication system

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.

Method of estimating location of terminal in switched-beamforming based wireless communication system

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Suwon-si, South Korea

Kyung-Hun Jang