Abstract: There is provided a method for estimating a position of a mobile node in a wireless sensor network. The method includes estimating a frequency offset between anchor nodes and estimating a difference between times when ranging frames from a mobile node are received by two anchor node, without use of a separate synchronization unit, such as a network synchronized clock supply unit that supplies a network synchronized clock via a cable, in a wireless sensor network, unlike a conventional method of estimating Time of Flight (TOF) using Two-Way Ranging (TWR) and Symmetric Double Sided-TWR (SDS-TWR) schemes. The estimated receiving time difference is directly applied to a Time Difference Of Arrival (TDOA) algorithm in order to estimate the position of the mobile node.

Abstract: The present invention relates to a method of estimating the position of a mobile node in a wireless sensor network using a passive mode OWR method. The method includes: estimating frequency offsets of anchor nodes and a mobile node; allowing the anchor nodes to sequentially transmit ranging frames; allowing the mobile node to receive the ranging frames and to estimate the difference between the reception times of signals from two anchor nodes; and applying the estimated difference between the reception times of the signals to time difference of arrival (TDOA) to estimate the position of the mobile node. According to the above-mentioned structure of the present invention, a plurality of mobile nodes can estimate their positions with a minimum number of ranging frame transmissions, without using a separate network synchronization unit. In addition, it is possible to easily construct a wireless sensor network for position recognition, and rapidly and accurately perform distance estimate using an OWR method.

Abstract: A LAN/USB bridge apparatus is provided. The LAN/USB bridge apparatus includes a wireless LAN/USB signal processor and a controller. The wireless LAN/USB signal processor receives a wireless LAN signal transmitted from a wireless LAN access point performing a bridging function between a wired LAN and a wireless LAN, transforms the received wireless LAN signal a UWB (ultra wide band) signal, and transmits the UWB signal to at least one of wireless USB apparatuses. The wireless LAN/USB signal processor also receives a UWB signal transmitted from the wireless USB apparatuses, inverse-transforms the received UWB signal to the wireless LAN signal, and transmits the wireless LAN signal to the wireless LAN access point. The controller controls and manages operations of the LAN/USB signal processor.

Abstract: An apparatus and method for context awareness by detecting intentions of a user in the ubiquitous environment using context information which is created by analyzing real world data collected from sensors are provided. The apparatus is configured of a sensor platform, a context-aware agent and a service provider. The sensor platform collects data of real world and transmits the collected data to the context-aware agent. The context-aware agent integrates the data of real world from the sensor platform, and stores and manages context information according to the integrated data. The service provider automatically controls objects to perform necessary operations to provide a predetermined intelligent services according to the context information received from the context-aware agent.

Abstract: Provided is a real-time wireless communication method for guaranteeing quality of service in a wireless personal area network (WPAN). When real-time data transmitted in a time slot of a current superframe has an error, a terminal, which was designated as a coordinator from among a plurality of terminals in a WPAN, allocates a time slot for retransmitting the real-time data to a next superframe and retransmits the real-time data in the allocated time slot of the next superframe. Therefore, quality of a real-time communication service in a WPAN can be guaranteed.

Abstract: Disclosed herein are a method for balancing the quality of a wireless communication channel wherein the quality of the wireless communication channel can be more accurately estimated and adjusted on the basis of the combination of observation results of the number of data frames failed to be transmitted in the past and a received signal strength (RSS), and reliability of data transmission over the channel can thus be increased, and a wireless communication apparatus using the same.

Abstract: An apparatus of managing sensing information for a sensor based home network and a method thereof are disclosed. The apparatus includes a sensor network to collect sensing information from multifunctional sensor nodes, a sensing information processing and managing unit for deciding the optimized context information through controlling and managing the collected sensing information according to all of the context information and providing services suitable to user's intention and environment. Therefore, the apparatus prevents collision and minimizes the interference generated between sensing information.

Abstract: A wireless resource allocation apparatus and method which maintain quality of service (QoS) in a wireless communication network are provided. The wireless resource allocation method includes calculating the number of medium access slots (MAS) to be allocated to at least one of a plurality of divided zones of at least one superframe, designating a reference location for MAS allocation to divided zones out of the plurality of divided zones of the superframe based on the calculated number of medium access slots, and allocating the medium access slots to the divided zones based on the designated reference location. Accordingly, more uniform service intervals can be supported, and thus efficient MAS resource allocation can be performed to satisfy media access control (MAC) based QoS requirements.

Abstract: Provided is a method for reserving a propagation time by estimating a channel environment in a wireless personal area network. The method includes the steps of: a) measuring a propagation range to the reception station upon starting data transaction with the reception station; b) measuring an average Strength Signal (ARSS) for determining a final transfer speed upon checking a transfer speed corresponding to the propagation range to the measured reception station based on a pre-defined table; c) determining a final transfer speed based on the transfer speed corresponding to the propagation range to the reception station according to a result that the measured ARSS is compared with Upper Bound RSS (URRS) and Lower Bound RSS (LRRS); and d) reserving a next propagation time according to the determined final transfer speed.

Abstract: Provided is an orthogonal frequency division multiplexing (OFDM) apparatus using a 3-dimensional (3D) signal constellation. The apparatus performs 2D inverse fast Fourier transform on a set of 3D subchannel signals that is mapped by a signal constellation including signal points distributed on the surface of a 3D sphere.

Abstract: There is provided a transceiving method of an audio signal using an UWB wireless communication scheme, including the steps of: extracting and analyzing the beacon frames to generate reserved transmission interval information previously reserved by the other UWB transmitters and/or adjacent wireless audio transmitters and information on audio source and channel; calculating an available transmission interval for each channel of audio sources by using the information on the audio source and channel of the other UWB transmitters; generating and transmitting a beacon frame based on the reserved transmission interval and the audio source and channel information; transmitting the audio signal at the reserved transmission interval by audio source and channel units; extracting and analyzing the beacon frame to generate audio source and channel information and reserved transmission interval information; and providing the audio source and channel information to the user.

Abstract: Provided is an intelligent management apparatus and method of a digital home network system.

Abstract: Provided is a combo access point (AP) device integrated with an WiMedia ultra wideband (UWB) based wireless universal serial bus (WUSB) and a wireless local area network (WLAN) AP. A combo AP device includes a wireless local area network (WLAN) AP block providing wire and wireless telecommunications interfaces, and a wireless universal serial bus (WUSB) block configured in one integral structure with the WLAN AP block and providing a ultra wideband (UWB) based wireless interface with WUSB devices using a WiMedia UWB interface mode. Configuring the combo AP device by matching the functions of the WLAN AP with the WiMedia UWB based WUSB interface can provide dual functions of the WUSB and the WLAN AP and allows personal computer users to easily access commonly shared WUSB devices.

Abstract: An apparatus and method for context awareness by detecting intentions of a user in the ubiquitous environment using context information which is created by analyzing real world data collected from sensors are provided. The apparatus is configured of a sensor platform, a context-aware agent and a service provider. The sensor platform collects data of real world and transmits the collected data to the context-aware agent. The context-aware agent integrates the data of real world from the sensor platform, and stores and manages context information according to the integrated data. The service provider automatically controls objects to perform necessary operations to provide a predetermined intelligent services according to the context information received from the context-aware agent.

Abstract: A wireless USB host apparatus supporting UWB is disclosed. The wireless USB host apparatus allocates a Media Access Slot of USB super frame to each of a plurality of wireless USB devices to transmit the real-time audio/video data as well as command data, control data and non real-time data through a single transmission channel. Also, the wireless USB host apparatus uses the ultra wide band to exchange data with the plurality of wireless USB devices to support the data transfer rate of about 53.3 to 480 Mbps, guarantees the QoS and supports transmission of the real-time audio/video data.

Abstract: An apparatus of managing sensing information for a sensor based home network and a method thereof are disclosed. The apparatus includes a sensor network to collect sensing information from multifunctional sensor nodes, a sensing information processing and managing unit for deciding the optimized context information through controlling and managing the collected sensing information according to all of the context information and providing services suitable to user's intention and environment. Therefore, the apparatus prevents collision and minimizes the interference generated between sensing information.

Abstract: Disclosed herein are a method for balancing the quality of a wireless communication channel wherein the quality of the wireless communication channel can be more accurately estimated and adjusted on the basis of the combination of observation results of the number of data frames failed to be transmitted in the past and a received signal strength (RSS), and reliability of data transmission over the channel can thus be increased, and a wireless communication apparatus using the same.

Abstract: An apparatus and method for supporting quality of services (QoS) for respective subscriber classes for an Ethernet passive optical network (E-PON) are provided. The method for supporting QoS includes specifying bandwidths and subscriber classes for respective ports for a plurality of subscriber termination systems connected to a service provider termination system; based on the bandwidth information, allocating bandwidths for respective subscriber ports of the subscriber termination systems; based on the subscriber class information, assigning IP addresses to respective subscriber of the subscriber termination systems according to subscriber class; and by using the bandwidths and IP addresses, supporting QoS according to subscriber class in transmitting and receiving data between the service provider termination system and the subscriber termination systems.

Abstract: The hands-free function provision apparatus for use in the mobile communication terminal using the ZigBee protocol includes: a mobile communication terminal for performing transmission/reception of a voice signal via a base station; a ZigBee coordinator for transmitting or receiving a predetermined display signal and a call control signal for establishing a call connection state to/from the mobile communication terminal, modulating or demodulating the predetermined display signal, the call control signal, and the voice signal using the ZigBee protocol; and a ZigBee device for performing wireless transmission/reception with the ZigBee coordinator by modulating or demodulating the predetermined display signal, the call control signal, and the voice signal using the ZigBee protocol, and visually providing the predetermined display signal.

Abstract: A multimedia data streaming server for effectively changing a transmit rate of multimedia data according to a network bandwidth that irregularly changes, and a method thereof are provided. The multimedia data streaming server includes a data storing unit, a monitoring unit, and a transmit rate controller. The data storing unit stores the multimedia data according to transmission levels, and the monitoring unit regularly monitors a network bandwidth state of a network streaming the multimedia data. The transmit rate controller increases the transmission level of the multimedia data to a default level if the network bandwidth state is getting bad while transmitting the multimedia data. Then, the transmit rate controller gradually increases or decreases the transmission level of the multimedia data from the default level gradually according to the network bandwidth state.