Abstract: An access point in an optical fiber-based high-speed optical wireless network is disclosed.

Abstract: An apparatus for transmitting signals between UWB networks is disclosed, which comprises: a signal converter for converting received optical signals from another UWB network into UWB signals, transmitting the converted optical signals within a UWB network, and converting UWB signals generated from within the UWB network into optical signals; and an optical signal transmission means for directing the received optical signals the signal converter and a further UWB network.

Abstract: Encoded data are transmitted with ultra-wideband (UWB) signals and a corresponding security key is transmitted through an infrared (IR) channel, to provide a secure method for transmitting a relatively large amount of data. The received security key is used by the receiver to decode the received data.

Abstract: A wideband erbium-doped optical fiber amplifier is disposed among an optical fiber through which a first and second band-band optical signals (for example, the C-band and L-band) are transmitted and forms a first optical path and a second optical path parallel to each other. The wideband erbium-doped optical fiber amplifier comprising a first amplifying section disposed on the first optical path, including a first erbium-doped optical fiber to amplify the first-band optical signals, a filter to gain-flatten the amplified first-band optical signals, wherein a reflected portion of the first band optical signal by the filter is directed to the second optical path; and a second amplifying section disposed on the second optical path, having a second erbium-doped optical fiber to amplify received second-band optical signals, wherein the reflected first-band optical signal is used to pump the second erbium-doped optical fiber.

Abstract: An indoor local area network (LAN) system using an ultra wide-band (UWB) communication system is provided. The indoor LAN system includes at least one remote terminal including a UWB module for converting input digital data to be transmitted into an analog signal of an ultra wide-bandwidth and wirelessly transmitting the converted analog signal via an antenna of the remote terminal. The UWB module receives an analog signal of the ultra wide-bandwidth via the antenna and converts the received analog signal into a digital signal. The indoor LAN system further includes at least one access point for performing USB-based wireless communication with the remote terminal in a corresponding area.

Abstract: A passive optical network (PON) for providing a large amount of data at high speed to subscribers is provided. In particular, a PON employing a multi-carrier CDMA in which a CDMA method is applied for an upstream signal is provided. The PON employing a multi-carrier CDMA includes: optical network terminals (ONTs) for transmitting CDMA-based data using multiple carriers to an optical line terminal (OLT) and for receiving Ethernet-based data transmitted from the OLT; the OLT for transforming CDMA-based data received from the ONT into Ethernet-based data, for transmitting the Ethernet-based data to a higher network, and for transmitting Ethernet-based date to the ONTs; and an optical coupler for coupling CDMA-based optical signals transmitted from the ONTs, for transmitting the coupled optical signal to the OLT, and for distributing an Ethernet-based optical signal transmitted from the OLT to the ONTs.

Abstract: A bidirectional WDM self-healing ring network is provided and includes an outer ring network and an inner network for processing N units of optical signals and for performing a protection switching by using the outer ring network when the inner ring network suffers a link failure.

Abstract: In a method for locating the center of a fiducial mark contained in an image, a certain region covering every fiducial mark in the image is defined. A region containing each fiducial mark within the certain region is extracted. The center of the fiducial mark within the region containing each fiducial mark is located to pixel accuracy. The center of the fiducial mark within the region containing each fiducial mark is located to sub-pixel accuracy according to the pixel level locating of the center of the fiducial mark.

Abstract: Disclosed is a spatial image information method and system for rapid and efficient storage in a relation type database and retrieval and management of spatial images acquired by a combined system of a global positioning system (GPS), an inertial navigation system (INS), and an image acquisition device (i.e., CCD camera). The spatial image acquired by the GPS/INS/CCD camera combined system is combined with an exterior orientation composed of a camera position (x,y,z), accelerated velocity, slope and direction at the moment the image is acquired and an interior orientation acquired by a camera calibration, so that calculation of a specified spatial coordinate information becomes possible.

Abstract: A temperature compensation device for an optical communication device or the like is constructed so that an error value, which is the difference between the current temperature and a reference temperature, is subjected to digital processing in a temperature comparison unit. A digital error voltage value is calculated and digital PID control is performed instead of analog PID which requires electric components such as a power op-amp, a resistor (R), and a capacitor (C). According to this construction it is possible to reduce the number of electric parts. It is also possible to accept various types of temperature sensors while using only one PCB regardless of the types of temperature sensors utilized.

Abstract: There is provided an apparatus for sharing and storing mass video data in a video geographic information system, and providing a usage of spatial indices for shared and stored information, and quick search for databases, the apparatus including: a map viewer for searching and outputting spatial geographic information; a video viewer for searching and outputting video data; a mass video data share, storage and management component for communicating with the map viewer and the video viewer, sharing and storing mass video data, which is not suitable for a storage in a single database, into a plurality of databases, and managing the plurality of databases to be accessible, integrated-searchable and manageable just like a single database; and a server including a share and storage information database for actually sharing and storing video data, which is managed by the mass video data share, storage and management component, offering a search, change, and management for each shared and stored data, and allowing to

Abstract: Disclosed is a temperature controller and method for maintaining an optical-communication device at a constant temperature regardless of ambient temperature variation.

Abstract: There is provided a video geographic information system for supplying the geographic information, which is maximized in a sense of reality, in a dynamic environment without a pre-processing for camera information and video stream, the system comprising a video server to load a video stream stored in a database and to transmit out of the video server through a network; a Geo server to load camera information stored in the database if image information and video frame information are input from the outside through a network, to retrieve geographic information stored in the database, to process the retrieved geographic information corresponding to a user request of queries and analysis, and to transmit the processed geographic information out of the Geo server through a network; a video player to receive a video stream from the video server through a network, to output the video stream, and to output image information and video frame information corresponding to a user request of selection, queries, analysis for

Abstract: A memory management apparatus for use in an open geographic information system includes a plurality of layers, each layer requiring a layer component, a disk buffer management component, a memory buffer management component and a spatial index management component; a layer collection component having a plurality of layer components, each layer component containing responsibility of managing all of the spatial data included in one layer accessed thereto through a data provider component; and a total memory management component. In the system the total memory management component manages totally a memory buffer to spatial data included in one or more layers, allocates a corresponding memory if each of memory buffer management components requests a memory buffer and frees a memory of a predetermined memory buffer management component when an available memory lacks.