Abstract: The inventive concept relates to a system supplying a constant current direct current power to serial loads connected in series with one another. The inventive concept is constituted by a constant current source power supply unit outputting a predetermined direct current, a load connection unit having the same rated current characteristic as the constant current source, a load connection unit having a rated current characteristic smaller than the constant current source, a load connection unit having a rated current characteristic greater than the constant current source, a load connection unit having a rated current characteristic greater or smaller than the constant current source and a circuit controlling or protecting them.

Abstract: The inventive concept relates to a system supplying a constant current direct current power to serial loads connected in series with one another. The inventive concept is constituted by a constant current source power supply unit outputting a predetermined direct current, a load connection unit having the same rated current characteristic as the constant current source, a load connection unit having a rated current characteristic smaller than the constant current source, a load connection unit having a rated current characteristic greater than the constant current source, a load connection unit having a rated current characteristic greater or smaller than the constant current source and a circuit controlling or protecting them.

Abstract: Provided is a high power efficiency optical-wireless transmitter capable of solving problems of low power efficiency, signal distortion due to non-linearity of output, large number of connection terminals, and non-uniformity of optical power intensities of optical sources. The high power efficiency optical wireless transmitter includes: an amplitude-to-array coder converting an amplitude of an electric signal input from a baseband modulator into optical source control signals so as to generate an optical output power corresponding to the electric signal; optical source driver groups driving optical sources based on the optical source control signals of the amplitude-to-array coder; and MMRS (modified mixed radix system) or MMRR (modified mixed radix system with Redundancy) optical source group driven by the optical source driver groups to generate various optical power intensities.

Abstract: A power generation system is provided. The power generation system includes a plurality of power generators, an output combiner, and a power controller. The power generators are configured to add a perturbation signal to each output. The output combiner is configured to combine the output powers of the power generators. The power controller is configured to cross-correlate the sum power of the perturbation signals of the power generators and the perturbation signals of the power generators and control the output powers of the power generators according to the cross-correlation result.

Abstract: An RF device is provided. The RF device includes a vibratile carbon nanotube having a nanotube natural frequency (f0), a negative electrode fixed to a first end of the carbon nanotube, a vibratile tuning electrode having a variable resonance frequency and facing a second end of the carbon nanotube, and a positive electrode electrically connected to a first end of the tuning electrode. A second end of the tuning electrode is adjacent to the second end of the carbon nanotube, and the carbon nanotube vibrates at a carrier frequency according to an external electromagnetic wave having the carrier frequency, and the tuning electrode having variable resonance frequency characteristics amplifies distance variation between the second end of the carbon nanotube and the second end of the tuning electrode to increase an electron emission sensitivity according to field emission.

Abstract: Wired/wireless optical signal modulation and demodulation apparatuses and methods using an intensity modulation/direct detection method and an orthogonal frequency division multiplexing (OFDM) method are provided. A unipolar OFDM symbol frame is generated by determining the polarity of each of a plurality of sub-frames of a bipolar OFDM symbol frame which comprises both a plurality of positive pulses and a plurality of negative pulses, inverting the polarity of the sub-frames which are determined to be negative, delaying one of the positive sub-frame and a positive sub-frame obtained through the inversion by the duration of the sub-frames, and multiplexing the result of the delaying and whichever of the positive sub-frame and the positive sub-frame obtained through the inversion is not the result of the delaying. The unipolar OFDM symbol frame can guarantee high power amplification efficiency and high transmission power efficiency, and is robust against a multi-path channel environment.

Abstract: Provided are a buried capacitor, a method of manufacturing the same, and a method of changing a capacitance thereof. The buried capacitor includes an upper electrode including at least one first hole, a lower electrode including at least one second hole, and a dielectric interposed between the upper electrode and the lower electrode.

Abstract: An RF device is provided. The RF device includes a vibratile carbon nanotube having a nanotube natural frequency (f0), a negative electrode fixed to a first end of the carbon nanotube, a vibratile tuning electrode having a variable resonance frequency and facing a second end of the carbon nanotube, and a positive electrode electrically connected to a first end of the tuning electrode. A second end of the tuning electrode is adjacent to the second end of the carbon nanotube, and the carbon nanotube vibrates at a carrier frequency according to an external electromagnetic wave having the carrier frequency, and the tuning electrode having variable resonance frequency characteristics amplifies distance variation between the second end of the carbon nanotube and the second end of the tuning electrode to increase an electron emission sensitivity according to field emission.

Abstract: Provided are a multi-aperture optical detector that can address structural problems such as a complex signal wiring in array type optical detectors, and a need for a plurality of low noise amplifiers, signal to noise ratio detectors, etc., and an optical signal detecting circuit including the multi-aperture optical detector. The multi-aperture optical detector includes transmission lines having two output terminals; and a plurality of unit optical detectors which respectively have random polarities through the transmission lines and are connected in parallel, and optical signals from each of the unit optical detectors are added and output through the two output terminals. The multi-aperture optical detector has a high operation band width and can detect optical signals with a high sensitivity by connecting a plurality of unit optical detectors that respectively have a low optical detecting sensitivity and are physically compact and small.

Abstract: Provided is a high power efficiency optical-wireless transmitter capable of solving problems of low power efficiency, signal distortion due to non-linearity of output, large number of connection terminals, and non-uniformity of optical power intensities of optical sources. The high power efficiency optical wireless transmitter includes: an amplitude-to-array coder converting an amplitude of an electric signal input from a baseband modulator into optical source control signals so as to generate an optical output power corresponding to the electric signal; optical source driver groups driving optical sources based on the optical source control signals of the amplitude-to-array coder; and MMRS (modified mixed radix system) or MMRR (modified mixed radix system with Redundancy) optical source group driven by the optical source driver groups to generate various optical power intensities.

Abstract: Provided is a radio frequency transceiver. The radio frequency transceiver includes: a receiving unit for converting a radio frequency signal received by an antenna into an intermediate signal based on an intermediate local signal; a transmitting unit for converting an intermediate signal into a radio frequency signal based on a radio frequency local signal; and a local signal generating unit for generating the intermediate local signal and the radio frequency local signal.

Abstract: An ultra wide band (UWB)-based wireless bridge converts wired serial data into a UWB signal with a quality of service, transmits it wirelessly, and inverts the UWB signal into wired serial data. The UWB-based wireless bridge includes: a physical layer processing portion; a protocol converting block; a UWB signal transceiving portion; and a control portion.

Abstract: Provided are an Internet protocol tuner that can classify Internet packets transmitted through the Internet into broadcasting packets and communication packets based on channel selecting information and extract transport stream from the broadcasting packets, and a method therefor. The Internet protocol tuner of the present research includes: a network interface unit for receiving an Internet packet; a packet classifying unit for classifying the Internet packets received; a transport stream extracting unit for extracting transport stream from the broadcasting packet; a transport stream transmitting unit for transmitting the transport stream; a transport stream receiving unit for receiving the transport stream from the decoding unit; a controller interface unit for receiving control information including channel selecting information from an external controller; and a tuning control unit for controlling the packet classifying unit, and controlling the transport stream extracting unit.

Abstract: Provided is an ultra wide band (UWB)-based wireless bridge that converts wired serial data into a UWB signal with a quality of service, transmits it wirelessly, inverts the UWB signal into wired serial data. The UWB-based wireless bridge includes: a physical layer processing means; the protocol converting means; the UWB signal transceiving means; and a controlling means.

Abstract: Provided is a radio frequency transceiver. The radio frequency transceiver includes: a receiving unit for converting a radio frequency signal received by an antenna into an intermediate signal based on an intermediate local signal; a transmitting unit for converting an intermediate signal into a radio frequency signal based on a radio frequency local signal; and a local signal generating unit for generating the intermediate local signal and the radio frequency local signal.

Abstract: Disclosed herein is an apparatus and method for scheduling packets using a credit based round robin in a high-speed communication network in which packets are transmitted to and received from a plurality of connections having respective speeds of service. The scheduling apparatus includes a packet pool for storing input packets; a token queue for storing tokens each having a connection identifier (ID) of an input packet stored in said packet pool, the round number (RN) of the connection, and a credit value (CV) for service; and a connection management unit for transmitting the input packets to said packet pool, reading the packets stored in said packet pool, generating the tokens each having a connection identifier (ID) of an input packet stored in said packet pool, the round number (RN) of the connection, and a credit value (CV) for service and transmitting them to said token queue, and servicing the packets of said packet pool designated by the token stored in said token queue.

Abstract: Provided is a radio frequency transceiver. The radio frequency transceiver includes: a receiving unit for converting a radio frequency signal received by an antenna into an intermediate signal based on an intermediate local signal; a transmitting unit for converting an intermediate signal into a radio frequency signal based on a radio frequency local signal; and a local signal generating unit for generating the intermediate local signal and the radio frequency local signal.