Agency for Defense Development

Other

Byung Chul Park

Jong Wan Heo

Kun Sup Kwon

Sung Jae Lee

Seung Ho Kim

Ki Min Hwang

An antenna apparatus includes: a parabolic reflector; a dielectric support pedestal; a sub-reflector connected to an upper part of the dielectric support pedestal; and a waveguide connected to a lower part of the dielectric support pedestal, wherein the parabolic reflector has a curved surface in which a ratio of a focal length to a diameter is greater than a preset value, and at least one corrugation configured to suppress a cross polarization is formed in a region of the dielectric support pedestal.

Antenna apparatus

According to the present disclosure, an antenna apparatus which includes a hollow pillar shaped waveguide extending in a first direction and at least one ridge protruding from an inner circumferential surface of the waveguide and extending in the first direction, wherein the ridge has at least one recessed groove formed in the first direction; and an antenna apparatus which includes the waveguide, the ridge and the iris structure protruding from the inner circumferential surface of the waveguide along a plane intersecting the first direction, are provided.

The embodiments generally relate to an antenna device that includes a cover having a specific shape to suppress a sidelobe of an elevation angle gain pattern which is caused by a radio-frequency (RF) device regardless of an avoidance area.

Antenna device for suppressing sidelobe

Disclosed is a method of preparing a copper electroplating layer having high adhesion to a magnesium alloy, which is advantageous because the usability of the magnesium alloy, having the highest specific strength among actually usable metals, can be increased through the development of a process of forming a uniform copper plating layer upon electroplating of the magnesium alloy. The method of preparing a copper electroplating layer having high adhesion to a magnesium alloy of this invention is characterized in that the magnesium alloy is pretreated with a plating pretreatment solution to form a film for electroplating, serving as a magnesium alloy pretreatment layer, exhibiting a uniform current distribution, which is then electroplated with copper to form the copper plating layer. According to this invention, through the pretreatment of the magnesium alloy, the adhesion of the copper plating layer to the film for electroplating formed on the magnesium alloy can be increased.

Growing community of inventors

Daejeon, South Korea

Byung Chul Park