Samsung Electronics Co., Ltd.

Industry-university Cooperation Foundation Sogang University

Yonsei University

Il-Whan Kim

Chung-Gu Kang

Sang-Boh Yun

Jeong-Hwan Lee

Sung-hyun Cho

Won-Hyoung Park

Jaehyuk Jang

Young-Bin Chang

Dong-seek Park

Seung-Joo Maeng

Young-Ky Kim

Young-Kwon Cho

Jae-Ho Jeon

Eun-Taek Lim

Sung-Soo Park

Sung-Soo Hwang

Jung-Min Ro

Dae-Sik Hong

Yeon-Woo Lee

Min-Seop Jeong

Seung-Young Park

Jun-haeng Cho

Soon-jin Choi

Ki-seok Chang

Yu-jin Lim

Kyeong Hur

Won-soo Kim

Kun-hyun Kim

A base station includes a center frequency setting unit, a local oscillator, a baseband processor, and an RF processor. In the event of a frequency band change, the center frequency setting unit sets a center frequency of a use frequency channel to have a predetermined offset value with respect to a center frequency before the frequency band change. The local oscillator generates an LO frequency signal according to the center frequency set by the center frequency setting unit. The baseband processor generates a downlink baseband signal. The RF processor uses the LO frequency signal to convert the downlink baseband signal into an RF signal prior to transmission.

Apparatus and method for supporting frequency rearrangement in wireless communication system

A resource allocation method in a wireless communication system for providing a communication service in a given system frequency band to access terminals (ATs) within a broad-band service area around an access point (AP) and to ATs within a narrow-band service area having a radius larger than the radius of the broad-band service area. In the resource allocation method, the system frequency band is divided into a Time Division Duplexing (TDD) interval and a Frequency Division Duplexing (FDD) interval in time, and the TDD interval and the FDD interval are defined as TDD resources and FDD resources, respectively. The TDD resources are allocated to an AT within the broad-band service area, and the FDD resources are allocated to an AT within the narrow-band service area.

Method of allocating resources using hybrid duplexing technique

A beacon scheduling method in multi-hop ad-hoc communications is provided. This method can prevent overhead in a manner that a base station (BS) transmits beacon slot information to a carrier sense multiple access (CSMA)/collision avoidance (CA) node (CN) and a gateway (GW) through contention-free time division multiple access (TDMA) communications at initial clustering, the CN and the GW performs a sequential clustering to forward the beacon slot information to a cluster head (CH), the CH aggregates joining messages from nodes and assigns non-colliding beacon slots to the nodes, and the GW uses a beacon slot frame of a beacon transmission period (BTP) used by its selected CH in a beacon reply period (BRP) as well. Accordingly, the CH does not need to separately perform the initialization to elect the beacon slot, and the GW also does not require a separate initialization to select the beacon relay slot.

Beacon scheduling method in multi-hop ad-hoc networks

An apparatus and method for reducing MAP channel overhead in a broadband wireless communication system. In a Base Station (BS), a traffic classifier classifies transmission data into a first group and a second group according to user channel information and packet sizes of the transmission data. A MAP channel configure configures a MAP channel to include information about users of the first group and positions of data for the users, information indicating whether users of the second group have succeeded in random access in a second uplink data region of a previous frame, and information about resource reservation for a current frame for the second group. A channel mapper maps the first group to a first downlink data region and maps the second group to a second downlink data region according to the MAP channel.

Apparatus and method for reducing map channel overhead in a broadband wireless communication system

A clustering method of a wireless sensor network is provided to minimize energy consumption. The clustering method includes the operations of determining a number of initial nodes within radio range of ordinary node, the ordinary nodes existing within radio range of a cluster head, and setting an ordinary node having a highest number of initial nodes among the ordinary nodes in the radio range of the cluster head, as a gateway. Because the number of usually large energy consuming cluster heads and gateways can be minimized, energy efficiency of wireless sensor network increases.

Clustering method of wireless sensor network for minimized energy consumption

A method for flooding a route request packet that is received at a node in a communication system constructed of at least three nodes including a source node that requests to establish a route and a destination node that receives the route request. One of a plurality of levels having different transmission periods is determined using a strength of a received signal of a measured packet. A transmission start point is selected at the determined level, and it is determined whether a route request packet is re-received before the selected transmission start point. The received packet is broadcast at the selected transmission start point when the packet is not re-received. The transmission start point is randomly selected within the transmission period or at the level in consideration of the number of the connected nodes.

Flooding method in ad-hoc network

A dynamic resource allocation method in an OFDMA system is provided. A base station determines if each of a plurality of SSs supports subchannel-based dynamic resource allocation. If an SS supports the subchannel-based dynamic resource allocation, the base station allocates resources to the SS on a subchannel basis. If the SS does not support the subchannel-based dynamic resource allocation, the base station allocates resources to the SS on a burst basis.

Dynamic resource allocation method for an OFDMA system

An ad-hoc network wireless communication system transmits data packets from one hop to another hop in a relay manner, and includes a transmitting node for transmitting a RTS message in order to transmit the data packets, and a receiving node, existing in a next hop of the transmitting node, for transmitting a CTS message in response to the RTS message transmitted from the transmitting node. The receiving node transmits the CTS message to another receiving node successively connected to the receiving node in response to the transmitted CTS message, and the transmitting node transmits the data packets to the receiving node in the case that the CTS message transmitted by the receiving node of the next hop is received over a predetermined number of times. The ad-hoc network wireless communication system can maximize the communication efficiency in a multi-hop network with its complexity minimized by extending a MAC protocol based on a IEEE 802.11 DCF to a reservation-based MAC in the multi-hop network.

Ad-hoc network wireless communication system and method thereof

Provided is a connection identification (CID) allocating method in a Broadband Wireless Access (BWA) communication system having a medium access control protocol data unit (MAC PDU) format with a header field including control information and a payload field including user data. The header field has a first CID field of a first length indicating a CID of a mobile subscriber station (MSS), a second CID field of a second length and indicating the CID of the MSS by being concatenated with a CID of the first CID field, and a type field indicating whether the second CID field is used. The method includes determining a CID to be allocated to a particular MSS; and if the length of the determined CID is equal to the first length, including the determined CID in the first CID field, including, in the type field, information indicating that the second CID field is not used, and transmitting the MAC PDU to the MSS.

Connection identification allocating system and method in a broadband wireless access communication system

Growing community of inventors

Incheon, South Korea

Il-Whan Kim