Abstract: An I/Q signal generating apparatus and phase shift apparatus using the same are provided, the I/Q signal generating apparatus including: a first resonance circuit whose one end is connected to a first input terminal and whose other end is connected to a first output terminal; and a second resonance circuit whose one end is connected to the other end of the first resonance circuit or a second input terminal, and whose other end is connected to a second output terminal, wherein the first resonance circuit and the second resonance circuit each include a resistor, a capacitor connected in parallel with the resistor, and an inductor connected in a form of a cross between the resistor and the capacitor.

Abstract: Disclosed is a dual-band phase shifter in which series/parallel resonance circuits are applied to a polyphase filter to implement a phase shifter, which is a core block of a multi-channel RFIC for implementing a phased array antenna system. The dual-band phase shifter may be configured by converting a capacitor (C) of an LC circuit or a CL circuit in the RFIC into a series resonance circuit and converting an inductor (L) thereof into a parallel resonance circuit, so that a signal generator operating in one frequency band can operate in a dual-band.

Abstract: A master reference oscillator system is provided. The master reference oscillator system includes a plurality of reference oscillators and a hybrid matrix receiving signals from the plurality of reference oscillators and outputting a plurality of output signals having the same signal magnitude, wherein at least two output signals among the plurality of output signals may have a phase difference.

Abstract: Provided is a FET resistive frequency mixing device having improved RF-LO and IF-LO isolations. The frequency mixing device includes: a field effect transistor (FET), a local oscillation matching circuit connected to a gate of the FET to transfer a local oscillation signal to the gate of the FET, a gate biasing circuit connected to the gate of the FET, a radio frequency (RF) matching circuit having a first terminal connected to a drain side of the FET and a second terminal serving as a RF terminal to receive or output a RF signal, an intermediate frequency (IF) matching circuit having a first terminal connected to the drain side of the FET and a second terminal serving as an IF terminal to receive or output an IF signal, and a series resonance circuit providing a path from the drain of the FET to ground for the local oscillation signal.

Abstract: Provided is a FET resistive frequency mixing device having improved RF-LO and IF-LO isolations. The frequency mixing device includes: a field effect transistor (FET), a local oscillation matching circuit connected to a gate of the FET to transfer a local oscillation signal to the gate of the FET, a gate biasing circuit connected to the gate of the FET, a radio frequency (RF) matching circuit having a first terminal connected to a drain side of the FET and a second terminal serving as a RF terminal to receive or output a RF signal, an intermediate frequency (IF) matching circuit having a first terminal connected to the drain side of the FET and a second terminal serving as an IF terminal to receive or output an IF signal, and a series resonance circuit providing a path from the drain of the FET to ground for the local oscillation signal.

Abstract: An integrated horn antenna with an integral polarization converter, and a method of manufacturing the integrated horn antenna are disclosed. The integrated horn antenna includes a horn, and a polarizer of which at least a portion is disposed in an internal space defined by an inner wall of the horn.

Abstract: Disclosed is a radio frequency low-loss power divider/combiner and power amplifier including the same, the power divider/combiner including a waveguide and a converter configured to convert an input signal received from an input signal terminal into a plurality of output signals and output the plurality of output signals to a plurality of output signal terminals corresponding to the plurality of output signals through the waveguide, wherein the waveguide includes the converter.

Abstract: Provided is an active true time delay apparatus for delaying a time and producing a gain in a superhigh frequency band using a field effect transistor (FET) and a similar semiconductor device. The active true time delay apparatus may include a delayer configured to delay an input signal for a predetermined length of time using at least one FET element connected in a distributed amplifier structure and an outputter configured to output the delayed input signal, and the delayer is disposed on a transmission line between an inputter and the outputter.

Abstract: A transmit/receive module for radar may include a radio frequency (RF) circuit unit including an RF substrate and an RF part; and a direct current (DC) power supply circuit unit including a printed circuit board (PCB) and a DC power supply circuit part. The RF circuit unit and the DC power supply circuit unit may be disposed so that a rear surface of the RF circuit unit faces a rear surface of the DC power supply circuit unit, and may be assembled to have a separate space using at least one separation wall.

Abstract: Provided is a frequency mixer including: an oscillator configured to output an LO signal; a first converter configured to convert an input IF signal into different first and second IF signals; a first mixer configured to output a first RF signal in which the first IF signal is mixed with the LO signal and a first leakage signal; a second mixer configured to output a second RF signal in which the second IF signal is mixed with the LO signal and a second leakage signal; and a second converter configured to mix and attenuate the first and second leakage signals and output an RF signal in which the first and second RF signals are mixed, in order to minimize leakage power of an LO signal generated in a local oscillator in a transmitter for a communication system using a high frequency of 70 GHz or higher, such as an E-band.

Abstract: Provided is a compact RF power amplifier including: a Doherty amplifier comprising a carrier amplifier comprising a first input impedance matching unit, a first amplifier, and a first output impedance matching unit, and a peaking amplifier comprising a second input impedance matching unit, a second amplifier, and a second output impedance matching unit, in which when a power level of the first RF amplified signal reaches a predetermined power level, the peaking amplifier outputs the second RF amplified signal.

Abstract: Provided is a 3-way balun for a double balanced mixer. This research provides a 3-way balun available for a planar-type double balanced mixer and a planar-type double balanced mixer employing the same. The 3-way balun includes a first output unit for receiving and outputting an input signal of a predetermined frequency; and second and third output units connected to the first output unit and outputting signals whose phase is different by 180 from a phase of a signal of the first output unit and amplitude is a half of an amplitude of the signal outputted from the first output unit.

Abstract: Provided is a RF switch for switching a path of a RF signal using a semiconductor transistor such as a field effect transistor (FET). The RF switch includes a plurality of resonators connected to a RF transmission line, and at least one of switching elements connected in shunt or in series between the plural of resonators. The plurality of resonators resonate by interacting with the switching elements when the switching elements are shorted or open.

Abstract: An interference signal reducing apparatus of a wireless communication system divides a signal that is input through a receiving antenna into a first signal and a second signal having a magnitude larger than that of the first signal and detects a frequency and a magnitude of an interference signal from the first signal, thereby generating an interference removal signal and then adds an interference removal signal to the signal that is input through the receiving antenna and thus reduces a magnitude of the interference signal.

Abstract: Provided is a 3-way balun for a double balanced mixer. This research provides a 3-way balun available for a planar-type double balanced mixer and a planar-type double balanced mixer employing the same. The 3-way balun includes a first output unit for receiving and outputting an input signal of a predetermined frequency; and second and third output units connected to the first output unit and outputting signals whose phase is different by 180 from a phase of a signal of the first output unit and amplitude is a half of an amplitude of the signal outputted from the first output unit.

Abstract: Provided is a RF switch for switching a path of a RF signal using a semiconductor transistor such as a field effect transistor (FET). The RF switch includes a plurality of resonators connected to a RF transmission line, and at least one of switching elements connected in shunt or in series between the plural of resonators. The plurality of resonators resonate by interacting with the switching elements when the switching elements are shorted or open.

Abstract: A broadband active balun using reactive feedback and a balanced mixer using the balun are provided. The broadband active balun comprises a common gate FET having a source connected to an input terminal, a gate connected to the ground, and a drain connected to a first output terminal; a reactive impedance element having one end connected to the drain of the common gate FET and the other end connected to one of the gate and the source of the common gate FET, and a common source FET having a gate connected to the input terminal, a source connected to the ground and a drain connected to a second output terminal. Accordingly, the active balun has a small physical size and a wide frequency band.

Abstract: Provided is a digital attenuation apparatus having ultra broadband and excellent attenuation characteristics. The digital attenuation apparatus includes an input port, an output port, a first transmission line, a second transmission line, a first switching device, a third transmission line, a first resistive element, a second resistive element, a fourth transmission line, a second switching device, a fifth transmission line, and a third resistive element.

Abstract: A tuning assembly for a radio frequency is disclosed. The tuning assembly includes: a tuning screw grasping unit integrally formed with a main body of the filter, which includes a tuning screw receiving unit and a fastening member for grasping a tuning screw; and a tuning screw inserted into the filter through the tuning screw receiving unit, wherein the filter is finely tuned by inserting the tuning screw into the filter through the tuning screw receiving unit and a female screw unit formed at the filter.

Abstract: Provided is a digital attenuation apparatus having ultra broadband and excellent attenuation characteristics. The digital attenuation apparatus includes an input port, an output port, a first transmission line, a second transmission line, a first switching device, a third transmission line, a first resistive element, a second resistive element, a fourth transmission line, a second switching device, a fifth transmission line, and a third resistive element.