Abstract: The present invention provides a multi-port amplifier which adopts a pair of SP4T switches and a pair of hybrid couplers in order to flexibly adjust an amplification mode. By using the proposed invention, the limited system flexibility and reconfigurability due to fixed input and output relations are overcome regardless of a component failure in a system. Moreover, signal amplification based on effective signal distribution and combination can be consistently performed according to various port configurations by different switching modes. Thus, the overall practicality of outputs comparing to the conventional multi-port amplifier can be effectively increased within an available lifespan of the system.

Abstract: Disclosed is an apparatus and a method for multiport amplification configured to amplify a signal input to a multi-input port and output the amplified signal to a multi-output port in order to normally transmit/receive a signal in a communication system. The apparatus and the method are configured to: amplify an input signal input through a multi-input port, detect a phase error and an amplitude error of the input signal, and then calculate a phase error value and an amplitude error value of the input signal; correct the phase error and the amplitude error of the input signal through the phase error value and the amplitude error value of the input signal; and then amplify the input signal of which the phase error and the amplitude error are corrected, and output the input signal to a multi-output port.

Abstract: Provided is a microwave switch including at least one semiconductor device connected to a transmission line and grounded in parallel, and at least one inductor connected in series to the transmission line. When the semiconductor device is shorted, the inductor may perform impedance matching through an interaction with the semiconductor device.

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: Provided is a directional coupler having high isolation, the directional coupler including a first directional coupler including a first main line and a first sub-line, and a second directional coupler including a second main line and a second sub-line, wherein the first directional coupler is connected to the second directional coupler in series.

Abstract: Disclosed is a low phase shift voltage variable attenuator. The low phase shift voltage variable attenuator may include: a first directional coupler including a first input terminal in which a signal is input, a first isolation terminal connected to a ground power source through a termination resistor, a first coupling terminal, and a first through terminal; a second directional coupler including a second input terminal through which an attenuated signal, which is the attenuated input input signal, is output, a second isolation terminal connected to a ground power source through a termination resistor, a second coupling terminal, and a second through terminal; and a signal attenuating unit connected to the first coupling terminal, the first through terminal, the second coupling terminal, and the second through terminal, and configured to attenuate a signal transmitted through the first directional coupler to transmit the attenuated signal to the second directional coupler.

Abstract: Provided is a radio frequency (RF) cavity filter including a tuning bolt holding member, the RF cavity filter including a top block, a bottom block to form a cavity along with the top block, a resonator disposed in the cavity, a tuning bolt to penetrate through the top block, and a tuning bolt holding member disposed to be in contact with one end of the tuning bolt to hold the tuning bolt, which may fix a position of the tuning bolt.

Abstract: Provided is an antenna apparatus which employs a small number of antenna devices and is intended to obtain a desired pattern without adjusting amplitude level and phase of each antenna device. The antenna apparatus includes a first ridge horn antenna, and a second ridge horn antenna spaced apart from the first ridge horn antenna by a determined distance. Here, a multi-beam pattern is generated using a third-order mode beam pattern of a synthetic beam obtained by synthesizing beams respectively radiated from the first and second ridge horn antennas. Accordingly, the antenna apparatus can be simplified, and a desired multi-beam pattern can be obtained without adjusting signal level and phase of each antenna device. Also, by employing the ridge horn antennas as array devices, the antenna apparatus can be used in a wide frequency band.

Abstract: A tunable filter device that changes a central frequency and a bandwidth is provided. The tunable filter device may include a body forming a cavity together with a cover, a resonator attached to or integrally formed on a lower surface of the cavity, a frequency-tuning element including a head and a shaft, the shaft passed through the cover and inserted in the resonator, and a cam disposed on the head to contact the head, wherein an insertion length of the shaft is controlled by the cam.

Abstract: Provided is a phase shifter for shifting a phase of a signal the phase shifter including an input unit to split an input signal into a plurality of signals having different phases, a connection unit to change at least one of magnitudes and phases of the plurality of signals, apply the changed plurality of signals to a plurality of loads, and receive a plurality of return signals generated when the applied signals are returned by the plurality of loads, and an output unit to generate an output signal having a predetermined phase difference from the input signal based on the return signals.

Abstract: Disclosed are a multi-beam antenna system and a method of controlling an output power thereof. An embodiment of the present invention includes a beam forming network configured to receive a plurality of signals to be a plurality of beams, to divide each of the plurality of signals to a plurality of divided signals, and to output a plurality of excited signals by adjusting and combining amplitude and phase of each of the plurality of divided signals, an MPA set having a plurality of MPAs configured to receive corresponding excited signals among the plurality of excited signals from the beam forming network and to control output powers of the received excited signals according to communication traffic, and a feed array having a plurality of feeds configured to form a multi-beam by being excited according to the amplitude and phase of the excited signals from the MPA set.

Abstract: A butler matrix includes at least one input coupler that is positioned at an input end of the butler matrix, receives an input signal, and divides and outputs it to a plurality of paths, and at least one output coupler that receives a signal from the input coupler and divides the signal into a plurality of paths to output it as an output signal. A separation coupler is formed in an intersecting path including an intersecting section at which transmission paths intersect among a plurality of paths through which a signal is transmitted to separate signals transmitted through different transmission paths. Further, a compensation coupler is formed in a path excluding the intersecting path to compensate a phase difference.

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: A butler matrix and a multi-port amplifier having the same, capable of splitting a single input signal into N-signals or combining N-signals into a single output are provided. The hybrids are provided in a predetermined disposition, the input port and the output port of the hybrids are provided in a predetermined direction and the waveguides are provided in a bended structure such that paths for connecting the hybrids have no crossing portion.

Abstract: Disclosed is a low phase shift voltage variable attenuator. The low phase shift voltage variable attenuator may include: a first directional coupler including a first input terminal in which a signal is input, a first isolation terminal connected to a ground power source through a termination resistor, a first coupling terminal, and a first through terminal; a second directional coupler including a second input terminal through which an attenuated signal, which is the attenuated input input signal, is output, a second isolation terminal connected to a ground power source through a termination resistor, a second coupling terminal, and a second through terminal; and a signal attenuating unit connected to the first coupling terminal, the first through terminal, the second coupling terminal, and the second through terminal, and configured to attenuate a signal transmitted through the first directional coupler to transmit the attenuated signal to the second directional coupler.

Abstract: Disclosed is a wide band sum & difference circuit for a monolithic microwave integrated circuit according to an exemplary embodiment of the present invention. The wide band sum & difference circuit for a monolithic microwave integrated circuit according to an exemplary embodiment of the present invention, including: a Range coupler having one terminal connected to a plurality of first ports that receive a signal and the other terminal connected to a plurality of second ports that output signals; one ?/4 line that is connected between one output terminal and one second port of the Range coupler in series; and one short stub ?/4 line that is connected with the other output terminal and the other second port of the Range coupler in parallel.

Abstract: The apparatus for receiving a wireless signal with anti-jamming includes: a wireless signal receiving unit receiving a wireless signal and including at least one antenna; and a jamming signal blocking unit disposed in front of the wireless signal receiving unit to block a jamming signal input from at least one direction and having a size or an interval from the wireless signal receiving unit determined according to at least one of an antenna pattern of the wireless signal receiving unit, a direction in which the jamming signal is input, and a level of the jamming signal. According to an exemplary embodiment of the present invention, it is possible to smoothly receive a targeted signal while blocking the jamming signal under the environment in which a general signal and the jamming signal coexist.

Abstract: Disclosed is a substrate integrated waveguide coupler. The substrate integrated waveguide coupler according to the present invention includes: a substrate; an upper conducting plate applied to an upper portion of the substrate; a lower conducting plate applied to a lower portion of the substrate; two peripheral via holes disposed parallel to each other on both sides of the substrate, respectively, and being of a pipeline type electrically connecting the upper conducting plate and the lower conducting plate to each other; and an inner via hole disposed between the two peripheral via holes, and having a center thereof separated by a preset distance and forming a short slot functioning to couple input signals.

Abstract: Disclosed is an apparatus for an antenna weightlessness deployment test. The apparatus for an antenna weightlessness deployment test includes: a pair of first direction mobile support shafts mounted in parallel at a predetermined distance; first direction mobile deployment apparatuses mounted to be supported by an air bearing so as to slidably move on the first direction mobile support shaft; a second direction mobile support shaft mounted to connect the first direction mobile deployment apparatuses with each other; and second direction mobile deployment apparatuses mounted to be supported by an air bearing so as to slidably move on the second direction mobile support shaft.