Abstract: A method and a device for determining transmission power in a multi-antenna communication system are provided. The method for determining transmission power includes calculating the power consumption of a transmission device, calculating the capacity of the transmission device, and determining transmission power for maximizing the energy efficiency of the transmission device by using the power consumption and the capacity thereof.

Abstract: Disclosed herein are an apparatus and a method for separating polysilicon from a carbon chuck. The apparatus carries out induction-heating by applying a high-frequency current on a carbon chuck with polysilicon adhering thereto (a polysilicon-carbon chuck) retrieved from a chamber for synthesizing polysilicon, to thereby selectively heat the carbon chuck.

Abstract: The present invention relates to a polysilicon filament manufacturing device, and more specifically, to a polysilicon filament binding device for manufacturing a polysilicon filament having a desired length by connecting polysilicon fragments cut from damage, etc. The present invention provides a polysilicon filament binding device comprising: a body part having a barrel-shape; a guide part provided inside the body part, guiding incoming polysilicon fragments; and a main light source for heating the binding surfaces of the polysilicon fragments.

Abstract: The present disclosure relates to a polysilicon preparation apparatus for preventing ground fault current and having an excellent effect of removing silicon dust. The polysilicon preparation apparatus includes a chamber comprising a housing with an opened lower portion and a base plate coupled to the lower portion of the housing, and a ceramic particle layer on an upper surface of the base plate, for preventing silicon dusts generated during a process from directly contacting the base plate and to be removed together with silicon dusts after the process.

Abstract: A transmitter configured to support a multimode and a multiband, using radio frequency (RF) digital-to-analog converters (DACs), includes a first RF DAC configured to transmit a first signal in a first frequency band, and a second RF DAC configured to transmit a second signal in a second frequency band different from the first frequency band. The transmitter further includes an impedance controller configured to adjust impedance of one of the first RF DAC and the second RF DAC operating in an impedance matching mode to adjust a frequency range of another one of the first RF DAC and the second RF DAC operating in a data transmission mode.

Abstract: An antenna and a communication system with the antenna are provided. The antenna may include a first layer including a plurality of folded stubs, a second layer including a pattern of the folded stubs, and a third layer connected to ground is disposed between the first layer and the second layer.

Abstract: A central control apparatus and method thereof include a traffic demand receiving unit, a traffic demand calculating unit, a base station efficiency calculating unit, and a base station management unit. The traffic demand receiving unit is configured to receive a required traffic demand and a current location of each of terminals. The traffic demand calculating unit is configured to calculate traffic of each of base stations to which a terminal is unassigned. The base station efficiency calculating unit is configured to calculate an energy efficiency of each of the base stations. The base station management unit configured to verify a base station with an optimum energy efficiency, to activate the base station with the optimum energy efficiency, and to assign the terminals of a corresponding region to the base station with the optimum energy efficiency.

Abstract: A method of determining a number of antennas, includes calculating a power used by a transmitting device. The method further includes calculating a channel capacity of the transmitting device. The method further includes determining a number of antennas of the transmitting device to be used based on the power and the channel capacity.

Abstract: A method for determining a transmission power in a multi-input multi-output (MIMO) system based on a cooperative transmission is provided. The method includes setting a power constraint condition of a transmitter and target quality information of a receiver. The method further includes determining the transmission power to be allocated to the transmitter to transmit the data to the receiver based on the power constraint condition and the target quality information.

Abstract: Provided is a method and device for increasing energy efficiency by adaptively performing clipping with respect to an input signal. The method may adaptively determine a clipping ratio (CR) based on a modulation method of the communication device and perform clipping based on the determined CR.

Abstract: Methods and apparatus for reducing a peak-to-average power ratio (PAPR) of an orthogonal frequency division multiplexing (OFDM) signal in an MIMO-OFDM communication system is provided, in which the method for reducing the PAPR of the OFDM signal may identify interference generated in an MIMO communication system, and adjust a clipping ratio (CR) for an effect of a clipping distortion to be less than an effect of interference.

Abstract: A method for determining a transmission power in a multi-input multi-output (MIMO) system based on a cooperative transmission is provided. The method includes setting a power constraint condition of a transmitter and target quality information of a receiver. The method further includes determining the transmission power to be allocated to the transmitter to transmit the data to the receiver based on the power constraint condition and the target quality information.

Abstract: A method for determining a transmission power in a multi-input multi-output (MIMO) system based on a cooperative transmission is provided. The method includes setting a power constraint condition of a transmitter and target quality information of a receiver. The method further includes determining the transmission power to be allocated to the transmitter to transmit the data to the receiver based on the power constraint condition and the target quality information.

Abstract: A system for saving energy through control of a sleep mode, and a method of operating the system are provided. The energy-saving system may enable a proxy device to maintain a minimum basic setup necessary for a communication when a host device enters a sleep mode, and may omit an operation performed based on the basic setup when the host device switches to a communication mode, thereby enabling a smooth switch between the sleep mode and the communication mode.

Abstract: A method and a device for determining transmission power in a multi-antenna communication system are provided. The method for determining transmission power includes calculating the power consumption of a transmission device, calculating the capacity of the transmission device, and determining transmission power for maximizing the energy efficiency of the transmission device by using the power consumption and the capacity thereof.

Abstract: A method and apparatus for user scheduling in a multi-user multiple input multiple output (MIMO) communication system are provided. The method includes identifying a user group comprising user terminals. The method further includes comparing power consumptions based on the user group. The method further includes scheduling the user terminals based on the comparing.

Abstract: Methods and apparatus for reducing a peak-to-average power ratio (PAPR) of an orthogonal frequency division multiplexing (OFDM) signal in an MIMO-OFDM communication system is provided, in which the method for reducing the PAPR of the OFDM signal may identify interference generated in an MIMO communication system, and adjust a clipping ratio (CR) for an effect of a clipping distortion to be less than an effect of interference.

Abstract: A transmitter configured to support a multimode and a multiband, using radio frequency (RF) digital-to-analog converters (DACs), includes a first RF DAC configured to transmit a first signal in a first frequency band, and a second RF DAC configured to transmit a second signal in a second frequency band different from the first frequency band. The transmitter further includes an impedance controller configured to adjust impedance of one of the first RF DAC and the second RF DAC operating in an impedance matching mode to adjust a frequency range of another one of the first RF DAC and the second RF DAC operating in a data transmission mode.

Abstract: A central control apparatus and method thereof include a traffic demand receiving unit, a traffic demand calculating unit, a base station efficiency calculating unit, and a base station management unit. The traffic demand receiving unit is configured to receive a required traffic demand and a current location of each of terminals. The traffic demand calculating unit is configured to calculate traffic of each of base stations to which a terminal is unassigned. The base station efficiency calculating unit is configured to calculate an energy efficiency of each of the base stations. The base station management unit configured to verify a base station with an optimum energy efficiency, to activate the base station with the optimum energy efficiency, and to assign the terminals of a corresponding region to the base station with the optimum energy efficiency.

Abstract: An antenna and a communication system with the antenna are provided. The antenna may include a first layer including a plurality of folded stubs, a second layer including a pattern of the folded stubs, and a third layer connected to ground is disposed between the first layer and the second layer.