Abstract: A calibration system of a phased array antenna is disclosed, including an antenna device comprising the phased array antenna, a measurement device configured to measure outputted signals from each radiating element arrayed in the phased array antenna to generate measured value data, and an analysis device configured to analyze the measured value data to generate and transmit analysis data to the antenna device, wherein the antenna device is configured to determine a phase offset to be applied to each radiating element based on the analysis data.

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: A monolithic microwave integrated circuit (MIMIC) for a phased array antenna system, and a phased array antenna system including the MIMIC are provided. The MIMIC includes a first amplifier including a first input terminal and a first output terminal, a second amplifier including a second input terminal and a second output terminal, a first switch connectable to the first input terminal and the second output terminal, and a second switch connectable to the first output terminal and the second input terminal.

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: Provided is a digital attenuation apparatus using a fine tuning function of an attenuation value, which includes: a plurality of digital attenuators connected in series; and an integrated attenuator finely attenuating the attenuation value when output values of the plurality of digital attenuators are input.

Abstract: A digital serial-to-parallel converter capable of minimizing a malfunction of a circuit by more stably performing an operation of a D flip flop in implementing a GaAs MMIC digital serial-to-parallel converter and a GaAs MMIC using the same are disclosed. The digital serial-to-parallel converter includes: a converter configured to convert a received clock signal, serial data, and load signal of TTL into a DCFL signal; a plurality of D flip flops configured to transmit the serial data received through the converter to a D flip flop of a next stage by the clock signal received through the converter and output the serial data of the D flip flop of the next stage by the load signal received through the converter; and a plurality of buffers configured to receive the serial data from the plurality of D flip flops to generate and output complementary signals.

Abstract: A digital serial-to-parallel converter capable of minimizing a malfunction of a circuit by more stably performing an operation of a D flip flop in implementing a GaAs MMIC digital serial-to-parallel converter and a GaAs MMIC using the same are disclosed. The digital serial-to-parallel converter includes: a converter configured to convert a received clock signal, serial data, and load signal of TTL into a DCFL signal; a plurality of D flip flops configured to transmit the serial data received through the converter to a D flip flop of a next stage by the clock signal received through the converter and output the serial data of the D flip flop of the next stage by the load signal received through the converter; and a plurality of buffers configured to receive the serial data from the plurality of D flip flops to generate and output complementary signals.

Abstract: Provided is a bias circuit. The bias circuit includes: a first resistor connected between a ground terminal and a first node; a first bias transistor having a drain connected to the first node and a source connected to a second node; a second bias transistor having a drain connected to the second node and a source connected to a negative voltage terminal; a third bias transistor having a drain connected to the ground terminal and a source connected to a third node; and a second resistor connected between the third node and the negative voltage terminal, wherein a gate of the first bias transistor is connected to the second node; a gate of the second bias transistor is connected to the negative voltage terminal; a gate of the third bias transistor is connected to the first node; and a gate bias voltage signal is outputted through the third node.

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: A frequency mixing apparatus includes a local oscillator, a signal distributor, a first frequency mixer and a second frequency mixer and a combiner. The signal distributor divides a signal generated from the local oscillator into two signals having a phase difference and outputs the two signals. The first frequency mixer has a first input port through which one of the two signals outputted through the signal distributor is inputted and a second input port connected to an RF signal. The a second frequency mixer has a first input port through which one of the two signals outputted through the signal distributor and a second input port is connected to a termination signal. The combiner combines signals respectively outputted from the first and second frequency mixers.

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 power amplifier used in a transmitter of a communication system. The power amplifier may include a power amplifier module to amplify power of a transmitting signal, an energy converter module to receive thermal energy generated by the power amplifier module and to convert the received thermal energy into electric energy, and a direct current (DC)-DC converter module to produce DC power using the electric energy generated by the energy converter module and to supply the produced DC power to the power amplifier module.

Abstract: Provided is a marchand balun device. The marchand balun device includes: a first line connected between a balanced terminal and a ground terminal; a second line disposed horizontally parallel to the first line and forming a parallel capacitance jointly with the first line; and a coupled line disposed vertically parallel to the first and second lines and forming a vertical capacitance jointly with one of the first and second lines.

Abstract: A multi-function MMIC operated by a switch using an amplifier is disclosed. A switch may be configured by connecting an input or an output of a plurality of amplifiers, and an insertion loss may be reduced by selecting a transmission mode or a reception mode of an MMIC using the switch. A noise characteristic, a power characteristic, and a gain characteristic may also be improved.

Abstract: A frequency mixing apparatus includes a local oscillator, a signal distributor, a first frequency mixer and a second frequency mixer and a combiner. The signal distributor divides a signal generated from the local oscillator into two signals having a phase difference and outputs the two signals. The first frequency mixer has a first input port through which one of the two signals outputted through the signal distributor is inputted and a second input port connected to an RF signal. The a second frequency mixer has a first input port through which one of the two signals outputted through the signal distributor and a second input port is connected to a termination signal. The combiner combines signals respectively outputted from the first and second frequency mixers.

Abstract: A multi-function MMIC operated by a switch using an amplifier is disclosed. A switch may be configured by connecting an input or an output of a plurality of amplifiers, and an insertion loss may be reduced by selecting a transmission mode or a reception mode of an MMIC using the switch. A noise characteristic, a power characteristic, and a gain characteristic may also be improved.

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.