Abstract: A microwave beam-forming antenna may include: a main reflector installed on one surface of an antenna body; an array feed horn installed on a center portion of the main reflector; a sub-reflector disposed to be spaced apart from the array feed horn on the main reflector; and a plurality of waveguide feeds respectively connected to a plurality of horn antennas arranged in the array feed horn.

Abstract: An operation method of a receiving device may comprise: receiving a periodic band-limited signal from a transmitting device; determining whether a carrier frequency of the periodic band-limited signal satisfies a constraint; converting the periodic band-limited signal into a digital high-frequency band signal by sampling the periodic band-limited signal at an extraction rate equal to or less than a Nyquist extraction rate when the carrier frequency satisfies the constraint; down-converting the digital high-frequency band signal into a digital baseband signal; rearranging samples of a plurality of periods of the digital baseband signal into one period; and generating a reconstructed signal by performing low-pass filtering with a bandwidth of the periodic band-limited signal on the digital baseband signal in which the samples are rearranged.

Abstract: A direct current-to-direct current (DC-DC) converter providing multiple operation modes includes a buck power stage configured to lower an input voltage, a boost power stage configured to increase the input voltage, and a multi-mode controller configured to control the buck power stage and the boost power stage, wherein the multi-mode controller is configured to generate a signal to control the buck power stage and the boost power stage according to the input voltage and an output voltage, and control the buck power stage and the boost power stage using the signal.

Abstract: An operation method of a receiving device may comprise: receiving a periodic band-limited signal from a transmitting device; determining whether a carrier frequency of the periodic band-limited signal satisfies a constraint; converting the periodic band-limited signal into a digital high-frequency band signal by sampling the periodic band-limited signal at an extraction rate equal to or less than a Nyquist extraction rate when the carrier frequency satisfies the constraint; down-converting the digital high-frequency band signal into a digital baseband signal; rearranging samples of a plurality of periods of the digital baseband signal into one period; and generating a reconstructed signal by performing low-pass filtering with a bandwidth of the periodic band-limited signal on the digital baseband signal in which the samples are rearranged.

Abstract: A direct current-to-direct current (DC-DC) converter providing multiple operation modes includes a buck power stage configured to lower an input voltage, a boost power stage configured to increase the input voltage, and a multi-mode controller configured to control the buck power stage and the boost power stage, wherein the multi-mode controller is configured to generate a signal to control the buck power stage and the boost power stage according to the input voltage and an output voltage, and control the buck power stage and the boost power stage using the signal.

Abstract: A communication method and apparatuses performing the same. The communication method includes arranging first subcarriers of a first frequency domain and second subcarriers of a second frequency domain based on a mirror point and performing communication based on an orthogonal frequency-division multiplexing (OFDM) communication scheme using at least one of the first subcarriers and the second subcarriers.

Abstract: A terminal for performing device-to-device (D2D) communication, according to an embodiment of the present invention, includes an antenna configured to transmit/receive an uplink channel signal and a downlink channel signal, a duplexer configured to separate a transmission/reception signal of the antenna into the uplink channel signal and the downlink channel signal, a switch configured to switch the uplink channel signal in a time division duplex (TDD) scheme so as to separate the uplink channel signal into an uplink transmission block and a first reception block, and a second reception block configured to convert the downlink channel signal provided from the duplexer into a baseband.

Abstract: Provided is a dual-polarized dipole antenna. The dual-polarized dipole antenna includes a substrate etched as first and second microstrip lines and provided in a cube, first to fourth feeding lines etched as third microstrip lines and disposed in a square type in a vertical direction to the substrate, and first to fourth radiation patches disposed in a square type in the vertical direction to the first to fourth feeding unit, wherein the first to fourth feeding units are respectively disposed on adjacent pairs of the first to fourth radiation patches. According to the present invention, a miniature dual-polarized dipole antenna having a wide bandwidth, high isolation characteristics, and a high gain can be provided.

Abstract: Provided is a transceiver.

Abstract: An error calibrating apparatus of an array antenna system according to an exemplary embodiment of the present invention is an error calibrating apparatus of an array transmitting antenna system having a plurality of array antennas and includes a calibrating signal generator which generates an error calibrating signal as a single frequency signal, in an area which does not interfere with a passband of a transmitted signal; an array RF transmitter which upwardly converts the transmitted signal into an RF band to transmit the signal to the plurality of array antennas; an error calibration estimator which correlates the error calibrating signal and the receiving single frequency signal received by passing through the array RF transmitter to estimate a transfer function of the array RF transmitter and extract a filter coefficient using the estimated transfer function; and a complex filter which calibrates an error of the transmitted signal by applying the filter coefficient to output the corrected transmitted sign

Abstract: A signal receiving device for measuring a characteristic of a wireless communication channel is provided. The signal receiving device includes an analog signal processor, an analog-digital converter, and a digital signal processor. The analog signal processor generates a band-limited signal by decreasing an intensity of a signal having an image frequency in a correlation operation result signal being a result of correlation operation, and generates an intermediate frequency signal by transforming the band-limited signal. The analog-digital converter converts the intermediate frequency signal into a digital signal.

Abstract: A signal receiving device for measuring a characteristic of a wireless communication channel is provided. The signal receiving device includes an analog signal processor, an analog-digital converter, and a digital signal processor. The analog signal processor generates a band-limited signal by decreasing an intensity of a signal having an image frequency in a correlation operation result signal being a result of correlation operation, and generates an intermediate frequency signal by transforming the band-limited signal. The analog-digital converter converts the intermediate frequency signal into a digital signal.

Abstract: Disclosed is a front-end apparatus of an RF transceiver connected with an antenna in a wireless communication system. The front-end apparatus of an RF transceiver using radio-frequency passive elements includes: a plurality of band pass filters configured a transmission signal and a reception signal; a first circulator configured to output a first transmission signal to a second terminal and output a second reception signal input; a second circulator configured to output a second transmission signal input into the first terminal to the second terminal and output a first reception signal input into the second terminal to the third terminal; a passive directional double pole and double throw switch configured to process a route to be changed depending on directions of an input and an output; a first antenna configured to transmit the first transmission signal; and a second antenna configured to transmit the second transmission.

Abstract: Provided is a transceiver.

Abstract: A terminal for performing device-to-device (D2D) communication, according to an embodiment of the present invention, includes an antenna configured to transmit/receive an uplink channel signal and a downlink channel signal, a duplexer configured to separate a transmission/reception signal of the antenna into the uplink channel signal and the downlink channel signal, a switch configured to switch the uplink channel signal in a time division duplex (TDD) scheme so as to separate the uplink channel signal into an uplink transmission block and a first reception block, and a second reception block configured to convert the downlink channel signal provided from the duplexer into a baseband.

Abstract: Provided is a micro base station antenna including a substrate etched with first and second micro strip lines, a first inverted F antenna, a second inverted F antenna facing the first inverted F antenna, and an isolator provided between the first inverted F antenna and the second inverted F antenna. According to the present invention, a micro base station antenna that has a wide bandwidth, a high gain, and an enhanced isolation characteristic can be provided.

Abstract: Provided is a dual-polarized dipole antenna. The dual-polarized dipole antenna includes a substrate etched as first and second microstrip lines and provided in a cube, first to fourth feeding lines etched as third microstrip lines and disposed in a square type in a vertical direction to the substrate, and first to fourth radiation patches disposed in a square type in the vertical direction to the first to fourth feeding unit, wherein the first to fourth feeding units are respectively disposed on adjacent pairs of the first to fourth radiation patches. According to the present invention, a miniature dual-polarized dipole antenna having a wide bandwidth, high isolation characteristics, and a high gain can be provided.

Abstract: Disclosed is a radio-frequency front-end apparatus that can be used in wireless communication systems performing transmission/reception by using a single antenna. The radio-frequency transceiving front-end apparatus using passive elements in a wireless communication system includes: a transmitting unit's hybrid coupler configured to divide and output a transmission signal into two outputs having a phase difference of 90°; a first circulator configured to receive a first output of the hybrid coupler through a first terminal thereof and output the received first output through a second terminal thereof; a second circulator configured to receive a second output of the hybrid coupler through a first terminal thereof and output the received second output through a second terminal thereof; and an output unit's hybrid coupler configured to receive transmission signals from the second terminal of the first circulator and the second terminal of the second circulator, and combine and output the received signals.

Abstract: The present invention relates to a wireless transceiver system for supporting a dual mode that simultaneously supports the Frequency Division Duplex (FDD) method and the Time Division Duplex (TDD) method in a certain frequency band. The present system supports the FDD system conducting transmission and reception simultaneously by using different frequency bands for transmission and reception as well as the TDD system temporally alternating transmission and reception by using the common frequency band among an upper frequency band and a lower frequency band used in the FDD system as well as another frequency band adjacent thereto, thereby selectively supporting both of the two communication systems in a wireless transceiver system.

Abstract: An apparatus and method for measuring radio relay channel are provided capable of easily measuring a radio relay channel on each radio link among a base station (BS), a relay station (RS) and a mobile station (MS) and providing a reliable result of measuring the characteristics of radio relay channel by controlling transmission/reception timing based on variation in operation time among the BS, the RS and the MS.