Patent application number | Description | Published |
20080224870 | APPARATUS AND METHOD FOR MANAGING POWER OF RFID TAG - An apparatus and method for managing power of a radio frequency identification (RFID) tag are provided. It is possible for the apparatus for managing the power of the RFID tag to effectively reduce power consumption of the RFID tag by measuring the power strength of a radio frequency (RF) signal received from an RFID reader and adjusting a level of transmission power based on the measured power strength of the signal. | 09-18-2008 |
20080224873 | APPARATUS AND METHOD FOR DETECTING WAKE-UP BURST OF ACTIVE RFID TAG - An apparatus and method for detecting a wake-up burst of an active RFID tag are provided. The apparatus and method, for detecting the wake-up burst of the active RFID tag, are capable of reducing power consumption of the RFID tag by enabling the RFID tag when a RFID reader starts to communicate. | 09-18-2008 |
20080267121 | NODE DEVICE AND METHOD FOR BEACON SCHEDULING IN AD-HOC NETWORK AND DATA TRANSMITTING METHOD THEREOF - Provided are a device of a node and method for beacon scheduling in an ad-hoc network and a data transmitting method thereof, which reduce power consumptions of nodes in an ad-hoc network when data communications between the nodes occur frequently. A beacon transmitting node checks its residual power. If the residual power is lower than a predetermined level, the beacon transmitting node notifies a plan to change its beacon cycle to other nodes. Thereafter, the beacon transmitting node increases the beacon cycle and transmits a beacon at the increased beacon cycles. Consequently, the beacon transmitting node can change its beacon cycle dynamically according to its power condition. Thus, the life span of the node can be increased. Therefore, it is possible to reduce an overhead of reconstructing a sensor network. | 10-30-2008 |
20090058612 | METHOD AND APPARATUS FOR AVOIDING COLLISION BETWEEN EACH OF RADIO FREQUENCY IDENTIFICATION READERS - Provided are a method and an apparatus for avoiding a collision between each of radio frequency identification (RFID) readers. The method and the apparatus divide the RFID readers into first RFID readers and second RFID readers according to a maximum output level, and set first frequency channels for the first RFID readers and second frequency channels for the second RFID readers, set frequency channel disposition information for each of the first RFID readers, generate a channel holding signal in each of the first frequency channels, and if a frequency channel usage request or a frequency channel return request is received from one of the first RFID readers, stop generating or generate the channel holding signal in a frequency channel related to the frequency channel usage or return request. In this manner, the collision between each of the RFID readers is avoided by preventing the second RFID readers from using the first frequency channels for the first RFID readers. Also, the method and the apparatus can efficiently manage frequency channels by controlling a ratio of the number of the first frequency channels to be used by the first RFID readers and the number of the second frequency channels to be used by the second RFID readers, according to usage frequency. | 03-05-2009 |
20090058613 | METHOD AND APPARATUS FOR COMMUNICATION BETWEEN READERS HAVING DUAL SENSITIVITY MODES - Provided is a method for communication with between readers having dual sensitivity modes for avoiding conflict between readers arising from interference each other when simultaneously used in a limited space. The method for communication between a tag and a reader using dual sensitivity modes for avoiding conflict between the reader and the tag includes: initializing the reader to a normal sensitivity mode; temporarily selecting a frequency channel by the reader; checking whether or not a different reader uses the selected frequency channel; repeatedly selecting another frequency channel if the other readers occupy the selected frequency channel; switching to a reduced sensitivity mode if the other readers do not occupy the selected frequency channel; and communicating with the tag by the reader in the reduced sensitivity mode. | 03-05-2009 |
20090103437 | Method of transmitting/receiving data in sensor network for reducing overhearing of sensor nodes - Provided is a method of transmitting/receiving data in a sensor node for reducing overhearing of sensor nodes, and a sensor network which implements the method. A sender node having transmission data from among a plurality of nodes which perform a low power listening (LPL) operation in an asynchronous manner at predetermined time intervals, generates a long preamble including short preambles, each having information including a destination address of the transmission data, a remainder of the long preamble, and a length of the transmission data, and sequentially transmits the second preamble and the transmission data. A receiver node from among the plurality of nodes determines whether a valid signal is sensed during an active state in the LPL operation. If it is determined that the valid signal is sensed, the receiver node receives the short preamble transmitted from the sender node. The receiver node determines a duration time of a deactivated state of the receiver node based on the received first preamble, thereby reducing overhearing in the sensor network. | 04-23-2009 |
20090103564 | Method and apparatus for controlling media access in sensor network - Provided are a method and apparatus for controlling media access in a sensor network and a method of managing traffic information. Since traffic information is exchanged between nodes and data is transmitted by using a dynamic long preamble according to receiver nodes, data transmission efficiency can be improved, energy consumed to transmit the long preamble can be reduced, and data transmission delay can be reduced as well. | 04-23-2009 |
20090109929 | MEDIA ACCESS METHOD PERFORMED BY READER IN DENSE READER ENVIRONMENT - Provided are a media access method and a reader for performing the media access method in a dense reader environment. The media access method divides an air time between the reader and a tag into a plurality of time slots, and operates in each of the plurality of time slots by using a listen before talking (LBT) technique. The plurality of time slots form a frame. Thus, the media access method can control the reader by performing channel scheduling between each of a plurality of readers and can efficiently recognize tags. | 04-30-2009 |
20090122733 | Coordinator in wireless sensor network and method of operating the coordinator - Provided are a coordinator in a wireless sensor network (WSN) which can improve transmission performance and prevent data loss, and a method of operating the coordinator. The method includes: scanning a transmitted beacon and storing information on a channel included in the beacon; when it is determined that a home channel communicating with a parent node is in an inactive mode on the basis of the information on the channel, in synchronization with the activation of another channel of the same hierarchical level as that of the home channel, activating a home channel communicating with a child node and communicating with the child node; and communicating with the child node through an auxiliary channel that has a frequency band different from those of the home channel communicating with the child node and home channels of other nodes and is always in an active mode. | 05-14-2009 |
20090122778 | APPARATUS AND METHOD FOR ASSIGNING TIME SLOT FOR TRANSMITTING BEACON IN WIRELESS SENSOR NETWORK - A method and an apparatus for assigning a time slot for transmitting a beacon in a wireless sensor network operated in a beacon mode are provided. In the method and apparatus for assigning a time slot according to the present invention, the total time slots assigned to the network are divided into N blocks and a node to which a time slot is exclusively assigned, among nodes to which a specific node is capable of directly and wirelessly transmitting, is selected as a parent node, the network is divided into two or more regions centering the parent node, a block having the time slot assigned to the parent node and adjacent blocks, among the N blocks, are respectively assigned to the regions, a time slot having been yet unassigned, among the time slots belonging to the block assigned to the region to which the specific node belongs among the divided regions, is assigned as the time slot of the specific node. | 05-14-2009 |
20090136833 | CASE FILM FOR POUCH TYPE LITHIUM PRIMARY BATTERY - Provided is a case film for a pouch type lithium primary battery which is suitable for application in a film type lithium primary battery. The case film for a pouch type lithium primary battery includes a flexible multilayer film in which a first polymer film, a second polymer film, a metal film, and a third polymer film are sequentially stacked. The first polymer film is formed of a hydrocarbon compound substituted or non-substituted with a halogen atom. The second polymer film is formed of an amorphous or low crystalline polymer having a crystallinity of 0 to 20%. The third polymer film is formed of a crystalline polymer having a crystallinity of 40 to 100%. | 05-28-2009 |
20090141667 | METHOD FOR ROUTING MESSAGE IN WIRELESS NETWORK BASED ON RELAY PROBABILITY - Provided is a method for routing a message in a wireless network based on relay probability. The method allows dynamic delivery of a message by calculating the relay probability of each node for message transmission, measuring the strength of a beacon signal received from a destination node, and determining a node that will relay a message based on the relay probability and the strength of beacon signal. | 06-04-2009 |
20090141741 | METHOD AND APPARATUS FOR CONNECTING SENSOR NETWORK TO HETEROGENEOUS NETWORK - Provided are a method and apparatus for connecting a sensor network to a heterogeneous network, in which an external network connected to the sensor network functions as a virtual personal area network (PAN) so that the same PAN address system is used between the sensor network and the external network by using a concept of a ‘virtual PAN’. According to the method and apparatus for connecting the sensor network to the heterogeneous network, a node of the sensor network can efficiently communicate with a node of the external network including the heterogeneous network by assigning the virtual PAN address to the node of the external network including the heterogeneous network without inserting any additional layer into the node of the sensor network. | 06-04-2009 |
20090146833 | Coordinator, gateway, and transmission method for IPv6 in wireless sensor network - Provided are a coordinator, a gateway, and a transmission method for applying IPv6 in a wireless sensor network (WSN). Dual addressing of a link local address using a short address used in the WSN and a global unicast address using an extended unique identifier (EUI) of a node makes it possible to support mobility of the WSN and communicate data with an external network. | 06-11-2009 |
20090147699 | METHOD OF SUPPORTING NODE PORTABILITY IN SENSOR NETWORK - Provided is a method of supporting node portability in a sensor network, wherein data transmission to a portable node can be guaranteed since even when the portable node is assigned with a different address by being associated with another network, the newly assigned address is transmitted to a parent node or a sink node that was previously associated with the portable node. | 06-11-2009 |
20090147715 | ENERGY SAVING METHOD IN WIRELESS NETWORK - Provided is a method of minimizing power consumed by each node in a wireless network when communicating with neighboring nodes. | 06-11-2009 |
20090147725 | CROSS-LAYER ROUTING METHOD IN WIRELESS SENSOR NETWORK - Provided is a cross-layer routing method in a wireless sensor network including: locating a destination node which is a final destination of data by a source node which generates the data; and determining an optimal relay node among one or more neighboring nodes using their position information for each hop and forwarding the data from the source node to the destination node through the determined relay nodes. Therefore, an effective and stable routing which reduces overheads of additional control messages used for stable data forwarding and reduces collisions in a shared channel by using wireless link layer characteristics can be implemented. | 06-11-2009 |
20090147760 | Method and apparatus for routing in wireless sensor network - Provided are a method and apparatus for efficiently performing routing in a wireless sensor network having a tree-hierarchical structure, the method and apparatus reducing the number of hops required for transmitting data. According to the method and apparatus, a node is determined as a proximal node from among nodes within range of a wireless signal of a transmission node, wherein the node is a node having the smallest difference from among differences between each of address values of the nodes within the range and an address value of a target node, and data is directly transmitted from the transmission node to the proximal node. | 06-11-2009 |
20090150699 | SLEEP SCHEDULING METHOD BASED ON MOVING DIRECTIONS OF TARGET IN SENSOR NETWORK - Provided is a sleep scheduling method based on directions of a target in a sensor network. A track subregion is set as an oval shape that is in proportion to a probability of the target moving in certain directions so as to track the target, and sleep patterns of sensor nodes in the tracking subregion are scheduled in consideration of a probability of the target moving in certain directions. As such, the energy efficiency of each sensor node in the sensor network can be improved. | 06-11-2009 |
20090154407 | Method of performing routing and allocating resources in wireless sensor network - Provided is a method of performing a routing and allocating a resource in a wireless sensor network. The method includes electing one or more cluster heads, each representing each of one or more clusters comprised of a plurality of sensor nodes, selecting a routing path between the cluster heads and the plurality of sensor nodes, selecting a frame length based on elements and distribution methods of the wireless sensor network and the routing path, forming a time slot resource allocation table for communication between the cluster heads, and exchanging the time slot resource allocation table between the cluster heads separated by one hop. The present invention can enhance the reliability of the wireless sensor network and QoS by effectively performing routing and allocating resources in such a manner that various data requirements can be satisfied. | 06-18-2009 |
20090154482 | ROUTING METHOD IN SENSOR NETWORK - Provided is a routing method capable of expanding a conventional tree routing to perform the efficient and safe key management in a sensor network environment that requires the symmetric key based key management. Each sensor node transmits a Route Reverse message to a sink node to set a reverse tree routing path. Therefore, it is possible to provide efficient and safe key management mechanism and communication environment by providing a bidirectional communication between a sink node and sensor nodes through an expanded tree routing such that a user is provided with a safe sensor network. | 06-18-2009 |
20090154485 | Apparatus and method for controlling multi-channel access - Provided is an apparatus and method for controlling multi-channel access in USN-based MAC. The multi-channel access control apparatus includes a channel scanner, a control channel preoccupier, and an available channel exchanger. The channel scanner scans at least one or more available channels among the N data channels in a Tx sensor node. The control channel preoccupier preoccupies, in the Tx sensor node, the control channel through control channel sensing and back-off and broadcasts a preamble on the control channel periodically. The available channel exchanger detects, in an Rx sensor node, the available channels available to the Tx sensor node on the basis of the received preamble, selects a channel available to the Rx sensor node among the detected available channels, and transmits information about the selected channel to the Tx sensor node. | 06-18-2009 |
20090156158 | SUPER REGENERATIVE RECEIVER AND METHOD OF SAVING POWER OF THE SAME - A low power super regenerative receiver and a method of reducing the power consumption of the low power super regenerative receiver are provided. The super regenerative receiver includes: an oscillator having a start-up time period starting oscillation that varies according to an existence of an input signal; and a power controller supplying power within the start-up time period of the oscillator. | 06-18-2009 |
20090161553 | APPARATUS FOR ANALYZING UBIQUITOUS SENSOR NETWORK PROTOCOL - An apparatus for analyzing a USN protocol includes a packet analyzer and a protocol analyzer. The packet analyzer collects packets communicated between USN sensor nodes through at least one or more channels. The protocol analyzer processes/displays the collected packets using an XML schema defined according to the USN protocol. Thus, the USN protocol analyzing apparatus can decode/encode packets collected through a plurality of channels. | 06-25-2009 |
20090161637 | COMMUNICATION APPARATUS AND METHOD IN WIRELESS SENSOR NETWORK - Provided are a communication method and apparatus of a wireless sensor network which uses at least one channel and has a tree structure. The method includes: generating windows, where a beacon interval is divided, according to each channel; selecting a window, which is not assigned to nodes that exist within a predetermined range from a certain node, from among the generated windows; and the certain node communicating with a child node of the certain node by using a channel to which the selected window belongs during a time corresponding to the selected window. | 06-25-2009 |
20090262689 | METHOD AND APPARATUS FOR ALLOCATING RESOURCES TO A NODE IN AD-HOC NETWORK - A method of allocating resources to a node in an ad-hoc network includes storing a basic frame structure including a predetermined number of time slots, in which time slots to be used by the node in the ad-hoc network are arranged at predetermined positions, determining a start time slot among the predetermined number of time slots included in the basic frame structure based on a path sequence number that is a number related to a position of the node on a routing path, and determining a frame structure including the predetermined number of time slots from the start time slot in the basic frame structure that circulates as a communications frame structure for communications of the node. | 10-22-2009 |
20100017511 | METHOD OF CONSTRUCTING TREE NETWORK - Provided is a method of constructing a tree network which includes a first node. The method comprises: (a) the first node determining if there is a child node and requesting a parent node to allow the first node to withdraw if there is no child node; (b) selecting a child node based on remaining amounts of battery power of each child node if there are child nodes of the first node; (c) exchanging positions of the first node and the selected child node and requesting the parent node to allow the first node to withdraw if the child node selected in operation (b) does not have child nodes; and (d) repeating operations (b) and (c) if the child node selected in operation (b) has child nodes. The present invention solves the problem of decreasing lifetimes of upper nodes that consume more battery power than lower nodes due to more traffic transmission and reception. | 01-21-2010 |
20100027449 | Transmitting apparatus, transmitting method, receiving apparatus, receiving method and channel status information updating method of sensor node based on multiple channels - Provided are a transmitting apparatus, a transmitting method, a receiving apparatus, a receiving method and a channel status information updating method of a sensor node based on multiple channels. The transmitting apparatus and method transmit a wake-up signal for switching neighbor nodes in a power-saving mode in a transmission range of the sensor node to a wake-up mode in which the neighbor nodes wait to receive a message from the sensor node through the control channel, transmit a preamble message including a list of unused available channels from among the data channels to a receiving node to which data is transmitted from among the neighbor nodes through the control channel, receive an acknowledgement message including information that indicates a channel selected from the available channels from the receiving node through the control channel, transmit a connection confirmation message for switching neighbor nodes other than the receiving node to the power-saving mode through the control channel, and transmit data to the receiving node through the selected channel. | 02-04-2010 |
20100090809 | METHOD AND APPARATUS FOR TRANSMITTING SENSOR STATUS OF RADIO FREQUENCY IDENTIFICATION TAG - Provided are a method and apparatus for transmitting a sensor status of a radio frequency identification (RFID) tag. The method and apparatus transmit an RFID tag identifier (ID) together with sensor data or sensor status information to an RFID reader, thereby enabling the RFID reader to receive the sensor status information about the RFID tag without additionally communicating with the RFID tag. | 04-15-2010 |
20100110888 | METHOD OF PREVENTING DATA COLLOSIONS IN BEACON-ENABLED ZIGBEE SYSTEM HAVING TREE ROUTING SCHEME - Provided is a method of preventing a data collision that occurs when two or more child nodes simultaneously transmit data to a parent node in a ZigBee network having a tree routing scheme and operating in a beacon mode. In the ZigBee system having the tree routing scheme and operating in the beacon mode, data communication to the parent node is performed in a beacon frame of the parent node. Here, when several child nodes exist under a single parent node, the child nodes transmit data to the parent node at the moment of receiving the beacon of the parent node, so that the data collision may occur when the child nodes simultaneously transmit the data to the parent node in the beacon frame of the parent node. In the method of preventing a data collision, each of the two or more child nodes is set to wait for its guard time (delay time) when transmitting data to the parent node to induce a normal slotted carrier sense multiple access with collision avoidance (CSMA-CA) operation. Therefore, the data collision can be prevented. | 05-06-2010 |
20100118737 | METHOD AND APPARATUS FOR CONSTRUCTING SYNCHRONOUS SENSOR NETWORK - Provided are a method and apparatus for using a synchronous sensor network medium access control (MAC) protocol such as a ZigBee or IEEE 802.15.4 low-rate wireless personal area network (WPAN). Also provided are a method and apparatus for constructing a ubiquitous sensor network (USN) of which a life is increased by using power beacons and reducing the number of unnecessary control packets (beacon packets), thereby reducing an initialization time between nodes and preventing beacon collision. According to the present invention, a beacon packet channel having a large output power and a data channel of which a transmission range is restricted by reducing an output power to be less than that of the beacon packet channel, may be simultaneously used. | 05-13-2010 |
20100128706 | APPARATUS AND METHOD FOR INCREASING OPERATION TIME IN IEEE802.15.4-2006 BEACON BASED WIRELESS SENSOR NETWORK - Provided are an apparatus and method for increasing operation time in an IEEE802.15.4-2006 beacon based wireless sensor network (WSN) with respect to the same amount of power consumption used by coordinators included in a WSN, by reducing unnecessary standby power consumption required during an active period of a super frame in a beacon-enabled mode. | 05-27-2010 |
20100207736 | MOBILE RFID READER AND RFID COMMUNICATION METHOD USING SHARED SYSTEM CLOCK - The present invention relates to a mobile radio frequency identification (RFID) reader and a RFID communication method using a shared system clock. According to the present invention, clock for synchronizing the mobile RFID readers can be shared without changing hardware of a conventional RHD device. Also, since the shared clock is used, a technology for preventing a collision with the readers can be easily realized in a mobile multi-reader environment. | 08-19-2010 |
20100207737 | TDMA CONTROL METHOD USED BY RFID READER VIA MOBILE PHONE BASE STATION AND MOBILE RFID READER - A time division multiple access (TDMA) control method used by a mobile radio frequency identifier (RFID) reader through a mobile phone base station and a mobile RFID reader are provided. Each mobile RFID reader occupies a frequency channel during a time slot allocated through a mobile communication base station, thereby avoiding interference between readers. | 08-19-2010 |
20100220653 | MULTI-PATH ROUTING METHOD IN WIRELESS SENSOR NETWORK - A multi-path routing method is provided a multi-path routing method for selecting appropriate multiple paths when information sensed from a source node is transmitted to a sink node in wireless sensor networks. The source node for transmitting the sensed information first transmits a Hello message to the sink node to identify the existence and position of the sink node. The sink node receives the Hello message and then re-transmits the Hello message with respect to all the received Hello messages. Respective middle nodes accumulate distances between the middle nodes while the Hello message is transmitted to the source node through a reverse path of the Hello message, and all the middle nodes maintain a real distance from the sink node. The source node receiving all the Hello messages can rout a plurality of appropriate paths through Hop-by-hop to the sink node by providing respective weights to an energy remaining amount, an appropriate transmission radius and a real distance from the sink node. Accordingly, priorities can be provided to lifetime of the source node, average energy consumption and the shortest path by adjusting the respective weights when routing the plurality of paths. In addition, appropriate paths can be routed considering the transmission success rate of a path, and a load balancing effect can be obtained using path cost. | 09-02-2010 |
20100241655 | APPARATUS FOR AND METHOD OF TRANSMITTING SENSING DATA OF SENSOR NODE FOR PROACTIVE DATA FILTERING IN WIRELESS SENSOR NETWORK - An apparatus for and a method of transmitting sensing data of a sensor node for proactive data filtering in a wireless sensor network are provided. In the apparatus and method, a request query of sensing data and timer parameters are received, local sensing data sensed in the sensor node in response to the received request query are detected, a driving time of a timer applying the timer parameters based on the request query is set, and the local sensing data are transmitted when the local sensing data do not overlap sensing data of a neighboring sensor node within a wireless reception range of the sensor node by overhearing the sensing data of the neighboring sensor node during the set driving time of the timer. Thus, since a data transferring path is selected considering the remaining energy of the node, the energy exhaustion of the node is distributed, thereby improve the lifespan of the network. | 09-23-2010 |
20100265889 | METHOD FOR RECOGNIZING POSITIONS OF A PLURALITY OF NODES WHICH CONSIST WIRELESS SENSOR NETWORK - A method for recognizing positions of a plurality of nodes which constitute a wireless sensor network is provided, the method comprises generating sub-maps which represent the relative position to neighbor nodes by taking each of the plurality of nodes as a reference; selecting a sub-map which takes a node with the highest connectivity as a reference from among the plurality of nodes; selecting a sub-map which takes a node with the highest connectivity as a reference, except for the node which becomes a reference of the selected sub-map among the nodes which are included in the selected sub-map; integrating the selected sub-maps into one map by matching the same nodes among the nodes which are commonly included in the selected sub-maps; and thereafter correcting positions of nodes which are included in the integrated map to real positions, whereby integrating order of the sub-map is adjusted using an information of the connectivity of the nodes, and the positions of the nodes which constitute the wireless sensor network is constituted are correctly recognized by correcting the position of the nodes. | 10-21-2010 |
20100278163 | METHOD OF DELIVERING DATA IN WIRELESS PRESONAL AREA NETWORK - Provided is a method of delivering data in a wireless personal area network. One of nodes forming the wireless personal area network broadcasts data including the address and the sequence number of one node to a plurality of other nodes, and broadcasts one of the data and other data to the other nodes depending on whether the data is received from the other nodes within a predetermined time. Accordingly, all the nodes on the network can receive data reliably and simultaneously power consumption is reduced, and thus the life of the network is extended. | 11-04-2010 |
20100306351 | METHOD AND APPARATUS FOR DOMAIN NAME AUTOCONFIGURATION IN IP-BASED WIRELESS SENSOR NETWORK - A method and apparatus for domain name autoconfiguration in an IP-based wireless sensor network is provided. The method includes: receiving sensor node information including position information for representing an installed position of a sensor node, a type of data to be provided by the sensor node, and an internet address of the sensor node; searching for area information including an administrative address corresponding to the position information of the sensor node; generating a domain name of the sensor node based on a type of the sensed data and the found area information; and binding the generated domain name with an internet address of the sensor node and registering the bound result in a domain name server. | 12-02-2010 |
20100308972 | COMMUNICATION METHOD FOR RADIO FREQUENCY IDENTIFICATION - Provided is a communication method for radio frequency identification (RFID). In order to transmit a command message with respect to an RFID tag, an RFID reader generates a command message comprising a command code indicating a type of command to be delivered to the RFID tag, a response format having one or more bits for indicating a type of additional data to be added to a response message to be received from the RFID tag, and an identifier identifying the RFID tag; and transmits the command message to the RFID tag, thereby allowing the RFID tag to immediately transmit the additional data via the response message in response to the command message. | 12-09-2010 |
20100314452 | APPARATUS AND METHOD OF GENERATING WAKE-UP SIGNAL IN BATTERY-POWERED PASSIVE TAG - An apparatus and method of generating a wake-up signal from a passive tag with a battery is provided. According to the present invention, since a wake-up signal is generated by a signal received from a Radio Frequency Identification (RFID) reader, battery life can be extended. That is, a wake-up signal can be generated for the battery to be operated according to a signal from the RFID reader so that the battery included in the tag can be controlled from the RFID reader, thereby controlling the amount of battery power consumed. Therefore, the battery life and the life of the tag including the battery can be increased. | 12-16-2010 |
20110006824 | WAKE-UP RECEIVER AND WAKE-UP METHOD USING DUTY CYCLING AND POWER OFF TECHNIQUE - Provided is a low-power wake-up receiver that is sensitive to electric waves, by which power consumed by a radio frequency (RF) transceiver of a sensor node in a ubiquitous sensor network (USN) is minimized. A wake-up receiver waking up a main transceiver includes a duty cycle signal generation unit controlling a duty cycle of a duty cycle signal; a burst signal detection unit receiving an input signal including a burst signal and a data signal based on the duty cycle signal, amplifying the input signal, and, if the amplified input signal is the burst signal, outputting a control signal; and a data signal detection unit re-amplifying the amplified input signal based on the control signal, and, if the re-amplified input signal is the data signal, outputting a wake-up signal. Power supplied to the duty cycle signal generation unit is interrupted based on the control signal and power is re-supplied to the duty cycle signal generation unit based on the wake-up signal. | 01-13-2011 |
20110116414 | APPARATUS AND METHOD FOR COMMUNICATION IN WIRELESS SENSOR NETWORK - Provided are a bridge system, a network management server, and communication methods at the bridge system and the network management server for efficient communication in a wireless sensor network (WSN). The communication method at the network management server includes communicating with bridge systems connected with a plurality of radio frequency (RF) regions within a personal area network (PAN) composed of sensor nodes using the same wireless channel, in which radio signals of the sensor nodes within the PAN reach the bridge systems, searching for a new channel to be used and an alternative bridge system which is to perform a channel change into the new channel based on information about the bridge systems upon receipt of an association failure report message from an error bridge system which is reported of an association failure from the RF region from among the bridge systems, sending a channel change request message to the found alternative bridge system, and adjusting channel information for the found alternative bridge system to the new channel and replacing information about sensor nodes connected to the found alternative bridge system with information about sensor nodes that are newly connected with the found alternative bridge system through the new channel. | 05-19-2011 |
20110131320 | APPARATUS AND METHOD OF DYNAMICALLY MANAGING SENSOR MODULE ON SENSOR NODE IN WIRELESS SENSOR NETWORK - Provided is an apparatus and method of dynamically managing a sensor module on a sensor node in a wireless sensor network. The apparatus includes an update unit, a request unit, and a transmission unit. If a change occurs in sensor data corresponding to each sensor node stored in a sensor information storage server, the update unit receives the sensor data from the sensor information storage server, and transmits the received sensor data to the corresponding sensor node. The request unit requests the sensor data from the sensor information storage server upon receipt of a sensor data request message from the sensor node. The transmission unit receives the requested sensor data from the sensor information storage server and transmits the received sensor data to the sensor node. | 06-02-2011 |
20110164573 | METHOD AND APPARATUS FOR ASSIGNING CHANNEL IN AD-HOC NETWORK - The present invention provides a method and apparatus for assigning a channel in an ad-hoc network, which can minimize beacon collision in the ad-hoc network and prevent channel overlapping or collision, and thus a channel can be efficiently assigned. The method of assigning a channel including: obtaining join order information which is information on the order in which a first node has been joined to a second node, which is a parent node, and level information of the second node in an ad-hoc network; determining a reference value for setting a channel that is to be assigned to the first node based on an address value of the first node, which is determined based on the join order information and the level information, a level value of the first node, a channel value of the second node, which is determined based on the level information, and the join order information; and determining a channel value of the first node by dividing the reference value by the maximum number of usable channels in the ad-hoc network. | 07-07-2011 |