Abstract: Provided is a general-purpose interface port that may interface with a sensor board including multiple types of sensor device drivers and download a sensor device driver from the sensor board, and a sensor node that may recognize a type of sensor included in the sensor board using the downloaded sensor device driver, the sensor node including a micro control unit that may process sensing data received from the sensor board, thereby providing a plug and play function between a micro control unit of a sensor node and a sensing unit including a sensor board in a Ubiquitous Sensor Network (USN) or a Wireless Sensor Network (WSN).

Abstract: Provided are a wake-up apparatus and wake-up method for a low power sensor node, and more particularly, to a wake-up apparatus and wake-up method for a low power sensor node, which can extend the battery life of the sensor node and minimize the amount of power consumed by an entire sensor network power by minimizing unnecessary power consumption of the sensor node. The wake-up apparatus for a low power sensor node includes: a wake-up signal detector receiving and detecting a wake-up signal of a sensor node; a wake-up radio frequency (RF) circuit unit filtering and amplifying the wake-up signal; and a wake-up baseband transducer detecting a wake-up address from the wake-up signal and comparing and verifying the wake-up address with a wake-up address that is provided from a server managing the sensor node.

Abstract: Provided are an apparatus and method for charging an internal battery in a wireless sensor network. A method for a slave sensor node to charge an internal battery in a sensor network includes estimating an hourly chargeable electric energy rate in a scan phase with a master sensor node, transmitting the estimated hourly chargeable electric energy rate using an association request message requesting association with the master sensor node after recognizing the master sensor node, requesting charging from the master sensor node and performing wireless charging when a power level of an internal battery requires charging, reporting the power level of the internal battery varied by the wireless charging to the master sensor node by predetermined time periods during the wireless charging, and stopping the wireless charging when the power level reported to the master sensor node reaches a predetermined power level.

Abstract: An apparatus and method for selecting antennas and nodes in a multi-input multi-output (MIMO) communication system are provided. The apparatus includes a reception unit which detects a communication initiation signal from among a plurality of received signals, a first combination unit which calculates communication capacity based on the communication initiation signal, searches for a combination of transmission antennas that can maximize the communication capacity, and performs communication using the identified combination of transmission antennas, a second combination unit which calculates an average signal-to-noise ratio (SNR) of each node based on the communication initiation signal and selects a node with a highest average SNR and performs communication using the selected node, and a selection unit which activates one of the first combination unit and the second combination unit and inactivates the other combination unit.

Abstract: 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.

Abstract: 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.

Abstract: Provided are a radio frequency identification (RFID) tag and a wake-up method thereof. The RFID tag includes: a power source that supplies a driving voltage; a continuous wave detector that receives the driving voltage from the power supply so as to detect a continuous wave in a signal received from an RFID tag reader; a command detector that selectively receives the driving voltage and detects a command in the signal; and a controller that executes the command detected by the command detector by supplying the driving voltage to the command detector if the continuous wave is detected, and stops the driving voltage from being supplied to the command detector if no command is received from the command detector for a predetermined time period.

Abstract: 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.

Abstract: Provided are an antenna apparatus for linearly polarized diversity antennas in a radio frequency identification (RFID) reader, and a method of controlling the antenna apparatus. The antenna apparatus includes: a plurality of linearly polarized diversity antennas disposed to have different directions to one another; a switching unit connecting the linearly polarized diversity antennas to the RFID reader; and a controller controlling the switching unit to selectively activate the linearly polarized diversity antennas.

Abstract: An apparatus allocates a channel used for inter-vehicle communications according to a traveling direction. The apparatus includes a traveling direction determiner for determining whether or not a traveling direction of a vehicle is changed; and a channel allocator for allocating the vehicle a previously allocated channel or a new channel based on a determined result of the traveling direction determiner. Further, a method allocates a channel used for inter-vehicle communications according to a traveling direction. The method includes the steps of determining whether or not a traveling direction of a vehicle is changed; and allocating the vehicle a previously allocated channel or a new channel based on a determined result in the above step.

Abstract: Disclosed is an asynchronous MAC based sensor node using a Wake-Up RF. The sensor node includes a main transceiver to transmit/receive data, a Wake-Up transceiver to transit a state of the sensor node; and a micro-control unit, which transmits a Wake-Up frame to at least one receiving node through the Wake-Up transceiver such that the receiving node is activated from an inactive state into an active state and transmits data to the activated receiving node through the main transceiver.

Abstract: Provided are an apparatus and method of transmitting and receiving a wake-up signal. The method of receiving a wake-up signal includes the following: operating a radio frequency (RF) receiving unit that receives a wireless signal through an antenna during an SFD detecting time, wherein the SFD detecting time is shorter than a predetermined SFD detecting time period, according to the predetermined SFD detecting time period and detecting a start of frame delimiter (SFD) to indicate that the received wireless signal is a wake-up signal to wake-up a node in a sleep mode; and detecting the wake-up signal by continuously operating the RF receiving unit when the SFD is detected. Power consumption that is used to receive the wake-up signal can be reduced.

Abstract: A large data transmission method in a sensor network based on a media access control (MAC) is provided. The method includes dividing data to be transferred into a plurality of data segments; generating a plurality of media access control (MAC) segmented data frames by including in each data segment an indication that the data is generated by segmentation and assigning a sequence number to the data segment; transmitting the generated MAC segmented data frames sequentially; receiving a MAC reception failure frame indicating reception failure for a predetermined period of time from a receiving sensor node after completing the transmitting of all the MAC segmented data frames; and retransmitting the MAC segmented data frames which correspond to at least one sequence number included in the received MAC reception failure frame. Accordingly, large data transmission times can be reduced in a MAC for a sensor network.

Abstract: Provided are a method of mediating a plurality of radio frequency (RF) transceivers, which is performed in a sink node in order to perform multi-radio interfacing between the sink node and a plurality of sensor nodes in a wireless sensor network (WSN), and a direct memory access (DMA) based data transfer method.

Abstract: A wireless sensor node is provided which is divided into functional modules on a function basis and operates the functional modules to cooperatively perform its individual functions. The wireless sensor node includes a wireless transceiver to wirelessly communicate with a control node; a primary configuration unit to set a node identification address in communication with a control node; a secondary configuration unit to use the node identification address to register with the control node and set an address for communication which is assigned by the control node; a basic power supply to supply power to modules for communication and sensor control; functional modules to perform data processing and sensor control; and a functional module activator to activate the functional modules according to a type of received data or an operation for data transmission.

Abstract: 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.

Abstract: 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.

Abstract: Provided are a method and apparatus for controlling a shared memory, and a method of accessing the shared memory. The apparatus includes a processing unit configured to process an application program, a user program unit configured to execute a program written by a user based on the application program of the processing unit, a shared memory unit connected to each of the processing unit and the user program unit through a system bus and configured to store data interchanged between the processing unit and the user program unit, and a control unit configured to relay a control signal indicating whether the system bus, by which the data is interchanged between the processing unit and the user program unit, is occupied, and control connection of each of the processing unit and the user program unit with the system bus in response to the control signal.

Abstract: 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.

Abstract: 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.