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. The access point is adapted to receive the analog signal of the ultra wide-bandwidth transmitted from the remote terminal and convert the received analog signal into an optical signal.
Abstract:
A connector assembly for coupling a corrosive gas supply pipe with a glass tube in an apparatus for fabricating an optical fiber preform using vapor deposition is disclosed. The connector assembly includes a first connector formed on an inner periphery thereof with a threaded portion, a second connector having a stepped surface on an inner surface and formed on an outer periphery with a threaded portion threadedly engaged with the first connector, an O-ring installed in the first connector and in close contact with the stepped surface when the second connector is threadedly engaged with the first connector, and resilient means for urging the O-ring against the stepped surface. The connector assembly consistently applies a resilient force to the O-ring functioning as a seal between the first and second connectors. For a long-running operation, even though the O-ring is cured, the fitting maintains a consistent sealing state to prevent metal material from being oxidized by the corrosive gas. As a result, fine oxidized metal particulars do not infiltrate into the gas supply pipe to prevent the optical fiber preform from deteriorating.
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:
Disclosed is a method for preparing a sheet for a sealing member of a solar cell, wherein the sheet has significantly low thermal shrinkage and high flexibility, and a superior capability of discharging bubbles during the manufacture of a solar cell module. The method for preparing a sheet for a sealing member of a solar cell according to the present invention comprises the following steps: (a) preparing a thermal adhesive resin having an olefin-based resin as a main component; (b) pulverizing the thermal adhesive resin and dispersing the resin powder; and (c) heating the thermal adhesive resin powder at a temperature lower than the melting temperature of the resin powder so as to prepare a sheet having a plurality of voids.
Abstract:
The present invention relates to an optical film comprising an aromatic based unit including 5 to 10,000 of units represented by Formula 6; a (meth)acrylate-based unit which is a copolymer of a (meth)acrylate derivative and maleimide; and a styrene-based unit which is a copolymer of a styrene derivative and maleimide, and a polarizing plate.
Abstract:
Disclosed is an Ethernet-IEEE 1394 repeater apparatus as a network transmission equipment for connecting between networks having the same or different protocols is disclosed. The apparatus includes a first protocol physical element for performing a modulation/demodulation process of a first protocol data; a second protocol physical element for performing a modulation/demodulation process of a second protocol data; an output interface for outputting the data through an output transmission, media; a first switch for switching the data input to one of the first protocol physical element and the second protocol physical element; a second switch, tuned with the first switch, for switching an output path to one of the first protocol physical element and the second protocol physical element, the output path being connected to the output interface; and a control unit for receiving a protocol information of data sent from one of the first protocol physical element and the second protocol physical element to control the first switch and the second switch based on the received protocol information, the one being selectively connected based on the current switching condition.
Abstract:
The present invention relates to an optical film comprising an aromatic based unit having chain having the hydroxy group containing portion and aromatic moiety; and a styrene-based unit comprising one or more styrene-based derivatives, and has absolute values of in-plane retardation (Rin) and thickness retardation (Rth) of 10 nm or less regardless of stretching, and a polarizing plate and an information technology apparatus including the same.
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:
A high-speed wireless LAN system is disclosed. The system includes a mobile station for transmitting/receiving data encrypted by a predetermined encryption method, communicating the data to associated access points by an ultra wide-band (UWB) communication method, and communicating an encryption key according to the encryption method to said associated access points by an optical or infra-red (IR) communication method; the plurality of access points, installed in a plurality of predetermined service areas, for relaying between the mobile station and a gateway of a remote place by communicating the data and the encryption key with the mobile station located in the corresponding service area by the UWB and the optical or IR communication methods and transmitting/receiving the data and the encryption key to/from the gateway by an optical communication method; and the gateway for providing an optical interface between an internal network and an external network, being provided with a plurality of gateway sub-modules for transmitting/receiving the data and the encryption key by communicating with the plurality of access points by the optical communication method, and transmitting a subscriber service transmitted from the external network to the corresponding access point.
Abstract:
An access point in an optical fiber-based high-speed optical wireless network is disclosed. The access point includes an antenna for receiving communication requirement signals, a switch for selectively outputting a corresponding signal according to the communication requirement signals, a bias control unit for selectively outputting bias current with variable intensity according to whether an output of the signal from the switch exists or not, on the basis of a threshold current; a bias operation unit for outputting input signals to the antenna when an input bias current is smaller than the threshold current and for outputting signals received by the antenna when an input bias current is larger than the predetermined threshold current, and a semiconductor optical amplifier for selectively performing an optical detection function of converting optical signals, which have been received through a first optical fiber from an central station, into electrical signals and sending the converted electrical signals to the bias operation unit, when a current smaller than the threshold current is input to the bias operation unit, and an optical modulation function of transmitting signals output from the bias operation unit through a second optical fiber to the central station, when a current larger than the threshold current is input to the bias operation unit.