Samsung Electronics Co., Ltd.

Korea University

Korea University Research and Business Foundation

Seoul National University

Bionano Health Guard Research Center

Sun Gi Kim

Hyo Hyun Choi

Jeong Geun Kim

Eui Jik Kim

Jin Ho Kim

Choong Seon Hong

Tae Shik Shon

Sun Shin An

Lynn Choi

Bum Jin Kim

Jehyok Ryu

Sae Young Ahn

Sang Hoon Lee

Jwa Min Nam

Jeong Sik In

Ju Wook Jang

Vu Thuy Dan Nguyen

Van Ca Phan

Jae Kyun Jung

Woo Kyung Sung

A communication method and apparatus using a virtual sink node in a wireless sensor network, in which location information about a destination node is acquired by a source node. If the location of the destination node is out of a transmission range of the source node, data including the location information about the destination node are transmitted from the source node to one of nodes adjacent to the source node, where the one node is typically closest to the destination node. The data are transmitted from the one node to another one of nodes adjacent to the one node, where another node is closest to the destination node, until the destination node is located within a transmission range of the one node. If the destination node is located within the transmission range of the one node, the data are transmitted from the one node to the destination node.

Communication method and apparatus using virtual sink node in wireless sensor network

A mobility management system and method is provided for efficiently support mobility to an IPv6 based LoWpan. The mobility management method for Internet Protocol version 6 (IPv6) based personal area network (PAN) moving with a mobile router according to the present invention includes detecting, at a mobile terminal, movement of the mobile router; determining whether the movement is an intra-network movement or an inter-network movement, transmitting, when the movement is an intra-network movement, a neighbor discovery request message to a gateway of a currently attached network and receiving a neighbor discovery response message containing a temporary address transmitted by the gateway in response to the neighbor discovery request message. When the movement is an inter-network movement, the gateway receives the binding acknowledgement message from a home agent and establishes a bidirectional tunnel with the home agent.

Mobility management system and method for internet protocol based low power wireless network

A method and apparatus for a sensor network having a plurality of reference nodes and a sensor node that enables the sensor node to compute a relative position through transmission range control and position mapping. In transmission range control, each reference node sends location information signals to the sensor node while varying transmission power. In position mapping, the sensor node forms a grid of vertical and horizontal lines corresponding to a square area defined by the neighboring reference nodes, extracts coordinates of intersections in the grid belonging to a shared region between areas covered by location information signals of various transmit power levels from the neighboring reference nodes, and sets the position of the sensor node to the middle points of the extracted coordinates. Each reference node sends a location information signal when a random backoff time expires after reception of a location information request signal.

Method and system for locating sensor node in sensor network using transmit power control

A method and system for transmitting data from a base station to a mobile station in a wireless communication system using a multiple hop relay scheme is In a multi-hop system having a plurality of nodes, performing bidirectional data transmission between the nodes comprises: grouping the plurality of nodes into a first node group to a fourth node group, and assigning data transmission intervals to the grouped node groups at each frame, the data transmission intervals dividing each frame in time; receiving, by a second group node, data from an upper group node at a first frame and, at the same time, receiving, by a third group node, data from a lower group node; and transmitting by the second group node data to the upper group node at a second frame and, at the same time, transmitting by the third group node data to the lower group node.

Method for transmitting data in a relay system and system therefor

A method for performing communication in the wireless sensor network is disclosed. The upper node transmits a beacon message to the lower nodes, wherein the beacon message distinguishes an indirect transmission interval, in which the upper node transmits downlink data to the plurality of lower nodes, from a direct transmission interval adjacent to the indirect transmission interval, in which the upper node receives uplink data from the plurality of lower nodes. The lower nodes determine the indirect transmission interval and the direct transmission interval from the received beacon message. The downlink data is transmitted from the upper node to the lower nodes in the indirect transmission interval. The uplink data is transmitted from the lower nodes to the upper node in the direct transmission interval. When communication is performed between the upper node and the lower nodes, the data can be efficiently transmitted from the upper node to the lower nodes.

Wireless sensor network and method for performing communication therein

A packet transmission method for a WPAN that for alleviating traffic concentration in an active period and improving network throughput by controlling packet transmission timing in the active period. A packet transmission method for a wireless personal area network including a coordinator operating with a specific duty cycle and a plurality of devices includes determining, when a packet is generated, whether there is another packet waiting to be sent; determining, if there is no other packet waiting to be sent, whether the network is in an inactive period; setting, when network is in an inactive period, a backoff time; and sending the packet when the backoff time has expired. The packet transmission method controls an initial backoff value adaptively to a duty cycle of the network.

Packet transmission method for wireless personal area network

A mobility header compression method and system for an IPv6-based LoWPAN is provided for supporting IPv6 mobility to the IPv6-based LoWPAN checks a packet carrying data and a first and a second headers containing transmission information about the data to determine whether the second header contains a compressed Internet Protocol version 6 (IPv6) information. When the second header contains a compressed IPv6 information, ands followed by a mobility header, a mobility support-indicative field of the first header is set to indicate that the second header is followed by the mobility header and the rest of the fields of the second header are compressed except for the mobility header-indicative field. A mobility information-indicative field of the mobility header is set to indicate inclusion of mobility information; and the rest of the fields of the mobility header are compressed except for the mobility information-indicative field.

Mobility header compression method and system for internet protocol-based low power wireless network

A communication terminal and method is provided for improving channel utilization efficiency in a wireless sensor network using contention-based channel access mechanism is disclosed. The communication method according to the present invention comprises initializing, when a packet transmission is required, a contention window to a size; resetting, when a channel is assessed to be busy, the size of the contention window in a hybrid expansion mode; and attempting, when the channel is assessed to be idle, the packet transmission through the channel.

Terminal and method for wireless sensor network for determining contention windows in contention-based channel access

A communication method and apparatus is disclosed that uses a received signal strength indicator (RSSI). In a sensor network including a plurality of nodes, a first node of the plurality of nodes receives a signal transmitted from a second node of the plurality of nodes, at least once. The first node also manages a link state with the second node according to the RSSI of the received signal. Therefore, the first node can receive signals from the plurality of nodes and then predict whether the second node moves. The first node can also predict a link state after the second node is moved so that communication can be performed through a link in a good state. Accordingly, the communication quality and the network performance of a network are enhanced.

Communication method and apparatus using received signal strength indicator in wireless sensor network

A wireless sensor network and data transmission method thereof provides for improving channel access efficiency and energy saving effect by using inventive carrier sensing mechanism. The data transmission method includes assessing a channel after initializing, when a packet to be transmitted is generated, a number of carrier sensing attempts (Ns) and a backoff value (W); determining, when the channel availability is assessed to be idle, whether W reaches 0; transmitting the packet if W reaches 0; and reassessing, if W does not reach 0, the channel after a duration corresponding W/(Ns-1) slot.

Network device and data transmission method thereof in wireless sensor network

For a sensor network having reference nodes and sensor nodes, A method and apparatus using a distance determining algorithm for a sensor network having reference nodes and sensor nodes. A distance determining algorithm is executed to determine an adequate distance between reference nodes within a preset error range, and a position location table is created. A sensor node sends a location information request to reference nodes, receives the position location table and location information from the reference nodes, and computes the coordinates of its position. Alternatively, without requesting transmission of the position location table, the sensor node may receive calculated coordinates of its position directly from a reference node.

Growing community of inventors

Seoul, South Korea

Sun Gi Kim