Abstract: The present disclosure relates to a liquid level measurement method and a liquid level measurement device using a fiber optic sensor. The device according to the present disclosure includes a fiber optic sensing unit configured to detect displacement of a metal rod fixed in a liquid storage tank according to inflow and outflow of a liquid into and from the liquid storage tank and a liquid level meter configured to measure a liquid level in the liquid storage tank using the displacement.

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 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: 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.

Abstract: Provided is an antenna apparatus which employs a small number of antenna devices and is intended to obtain a desired pattern without adjusting current 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 predetermined 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 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 deployable reflectarray antenna includes a plurality of reflectarray antenna panels each having one edge connected to be folded and unfolded. Each reflectarray antenna panel includes a membrane having reflecting elements and a support frame. The support frame includes outer frames surrounding edges of the membrane, and a plurality of reinforcing members disposed in a vertical direction between the outer frames in a length direction.

Abstract: Provided is a shockless separation device for a space application configured to fix a deployment part to a satellite while launching the satellite, and shocklessly separate the deployment part from the satellite when the satellite enters its orbit in space. The shockless separation device includes a fastening projection, a fastening recess part and a heating part. The fastening projection part is provided in the deployment part. The fastening recess part is provided in the satellite, and formed of a shape-memory alloy such that the fastening projection part is inserted into the fastening recess part to be fixed before heating, and when the fastening recess part is heated to a transformation temperature or more, the inside of the fastening recess part is recovered to be expanded to separate the fastening projection. The heating part is controlled to heat the fastening recess part when the satellite enters its orbit in space.

Abstract: A 7 pole resonator filter including a dual mode resonator and a triple mode resonator may include a first dual mode resonator including independent adjusting portions adjusting each frequency according to two resonant modes, and having at least one conductive surface, a triple mode resonator including independent adjusting portions adjusting each frequency according to three resonant modes separate from the two resonant modes, and having at least one conductive surface, a first connecting portion electrically connecting the first dual mode and the triple mode resonators, a second dual mode resonator including independent adjusting portions adjusting each frequency according to two resonant modes separate from the two resonant modes and the three resonant modes, and having at least one conductive surface, and a second connecting portion electrically connecting the triple mode resonator and the second dual mode resonator. The three dual mode resonators have similar shapes.

Abstract: A cable network antenna and a manufacturing method thereof are provided. The cable network antenna maintains correct positions of nodes at which a plurality of cables intersect, using a circumferential truss that minimizes transformation of a reflecting surface. Accordingly, accuracy of the reflection surface is achieved.

Abstract: Provided is a structure for reducing an acoustic load. The structure includes a tape structure. The tape structure includes an attachment part configured to be attached to a substrate, and an off-position part spaced apart from the substrate and having at least one ventilation hole. Therefore, owing to the resilience of the attachment part and shock-absorbing ability of an air layer formed between the off-position part and the substrate, an acoustic load can be reduced. In addition, since air can flow through the ventilation hole, the attachment part of the tape structure may be not separated by variations of air pressure.