Abstract: A reflective antenna apparatus according to an exemplary embodiment of the present invention includes a feeder which receives an electromagnetic wave from a transmitter and distributes the electromagnetic wave to the antenna apparatus; a sub reflector which has a step formed to generate an orbital angular momentum (OAM) mode electromagnetic wave; and a main reflector which has a step formed to generate the same electromagnetic wave as the OAM mode generated by the sub reflector and cancels the OAM mode electromagnetic wave generated by the sub reflector and an OAM mode electromagnetic wave generated by the main reflector to radiate the electromagnetic waves to a far field.

Abstract: A method for use with a reflectarray antenna for wireless telecommunication is described. The method involves providing a reflectarray antenna, and adjusting a phase of a scattered field of the reflectarray antenna for generating different radiation patterns for angular mode-based multiplexing. The reflectarray antenna includes a ground plane, a dielectric substrate attached on the ground plane; and a first antenna patch formed on one side of the dielectric substrate. Further, the reflectarray antenna includes a second antenna patch formed adjacent to the first antenna patch with a separation area therebetween; and a phase adjustment member disposed in the separation area. The phase of the scattered field of the antenna is adjusted by changing a DC voltage of the phase adjustment member.

Abstract: A reflective antenna apparatus according to an exemplary embodiment of the present invention includes a feeder which receives an electromagnetic wave from a transmitter and distributes the electromagnetic wave to the antenna apparatus; a sub reflector which has a step formed to generate an orbital angular momentum (OAM) mode electromagnetic wave; and a main reflector which has a step formed to generate the same electromagnetic wave as the OAM mode generated by the sub reflector and cancels the OAM mode electromagnetic wave generated by the sub reflector and an OAM mode electromagnetic wave generated by the main reflector to radiate the electromagnetic waves to a far field.

Abstract: Provided is an apparatus and method for simultaneously transmitting and receiving orbital angular momentum (OAM) modes. An apparatus for transmitting OAM modes may include a mode multiplexing apparatus, and a matrix array antenna configured to output OAM modes for electromagnetic waves based on mode signals, wherein the mode multiplexing apparatus may include hybrid couplers configured to generate a plurality of output signals having different phases and different amplitudes by mixing and distributing a plurality of input signals, and phase shifters configured to generate the mode signals by shifting the phases of the output signals.

Abstract: The disclosure provides an antenna apparatus. Disclosed is an antenna apparatus comprising a power feeding unit receiving an electromagnetic wave from a transmitter and providing the received electromagnetic wave to the antenna apparatus, a sub reflector generating an OAM (Orbital Angular Momentum) mode electromagnetic wave, and a main reflector reflecting the generated OAM mode electromagnetic wave to a far field region.

Abstract: Disclosed is a method for performing a 3D image reconstruction at a high speed and high resolution, regardless of a measurement distance. Specifically, a weight for image reconstruction is previously set, and a 3D image reconstruction algorithm is performed at a high speed, without reducing a resolution, by a parallel processing for image reconstruction, a computation of a partial region using a database based on a measurement result, and a generation of a variable pulse waveform.

Abstract: A reflectarray antenna for wireless telecommunication includes a ground plane; a dielectric substrate attached on the ground plane; and a first antenna patch formed on one side of the dielectric substrate. Further, the reflectarray antenna includes a second antenna patch formed adjacent to the first antenna patch with a separation area therebetween; and a phase adjustment member disposed in the separation area to adjust a phase of a scattered field of the antenna by the appliance of a DC voltage.

Abstract: A signal transmission and reception method includes generating a plurality of electromagnetic wave mode functions having orthogonality in a spatial domain using a plurality of input signals, synthesizing and wirelessly transmitting the generated electromagnetic wave mode functions, receiving a revolution division multiplexing electromagnetic wave having characteristics of phase rotation in directions of an azimuth angle and an elevation angle, and discriminating the electromagnetic wave mode functions through an orthogonal operation, and restoring an output signal through correction of the discriminated electromagnetic wave mode functions.

Abstract: An antenna radiation pattern measurement device that measures a radiation pattern of an AUT by using a source antenna includes a control unit, an analysis unit, and a measurement unit. The control unit controls driving of the source antenna and the AUT. The analysis unit measures an electric field value from a radio frequency (RF) signal that is transmitted from one of the source antenna and the AUT and received by the other antenna. In addition, the measurement unit controls the control unit and the analysis unit and measures a radiation pattern of the AUT by using the electric field value.

Abstract: A camera based positioner (CBP) for near-field measurement and a method therefor, and a near-field measurement system are provided. A measurement probe and an antenna under test (AUT) are automatically aligned to a position for near-field antenna measurement by recognizing a position and a rotation angle of the AUT based on an interval and an angle between neighboring laser sources represented in an image taken by emitting laser beams from at least two laser sources located with a predetermined interval and a predetermined angle.

Abstract: Disclosed is a method for performing a 3D image reconstruction at a high speed and high resolution, regardless of a measurement distance. Specifically, a weight for image reconstruction is previously set, and a 3D image reconstruction algorithm is performed at a high speed, without reducing a resolution, by a parallel processing for image reconstruction, a computation of a partial region using a database based on a measurement result, and a generation of a variable pulse waveform.

Abstract: There is a provided a system for measuring an antenna radiation pattern in a Fresnel region, including: a fixed antenna and a movable antenna located in the Fresnel region to acquire a far-field radiation pattern; a moving unit for moving upward or downward to adjust a measuring angle of the movable antenna; a rotation unit to rotate a rotation shaft horizontally; a vector network analyzing unit for outputting an radio frequency (RF) signal to one of the fixed antenna and the movable antenna as a transmission antenna, receiving the RF signal received through the other one of the fixed antenna and the movable antenna as a receiving antenna, and detecting a complex value; a control and communication unit for controlling the vector network analyzing unit and a control unit, and performing a data communication; and the control unit for providing a vertical/horizontal rotation force to the moving unit and the rotation unit under a control of the control and communication unit.

Abstract: An antenna radiation pattern measurement device that measures a radiation pattern of an AUT by using a source antenna includes a control unit, an analysis unit, and a measurement unit. The control unit controls driving of the source antenna and the AUT. The analysis unit measures an electric field value from a radio frequency (RF) signal that is transmitted from one of the source antenna and the AUT and received by the other antenna. In addition, the measurement unit controls the control unit and the analysis unit and measures a radiation pattern of the AUT by using the electric field value.

Abstract: A camera based positioner (CBP) for near-field measurement and a method therefor, and a near-field measurement system are provided. A measurement probe and an antenna under test (AUT) are automatically aligned to a position for near-field antenna measurement by recognizing a position and a rotation angle of the AUT based on an interval and an angle between neighboring laser sources represented in an image taken by emitting laser beams from at least two laser sources located with a predetermined interval and a predetermined angle.

Abstract: There is a provided a system for measuring an antenna radiation pattern in a Fresnel region, including: a fixed antenna and a movable antenna located in the Fresnel region to acquire a far-field radiation pattern; a moving unit for moving upward or downward to adjust a measuring angle of the movable antenna; a rotation unit to rotate a rotation shaft horizontally; a vector network analyzing unit for outputting an radio frequency (RF) signal to one of the fixed antenna and the movable antenna as a transmission antenna, receiving the RF signal received through the other one of the fixed antenna and the movable antenna as a receiving antenna, and detecting a complex value; a control and communication unit for controlling the vector network analyzing unit and a control unit, and performing a data communication; and the control unit for providing a vertical/horizontal rotation force to the moving unit and the rotation unit under a control of the control and communication unit.

Abstract: The present invention provides a broadband slot array antenna that can be implemented with lower cost by using a single dielectric layer and a metal layer, and makes easy to implement an active integrated antenna. The broadband slot antenna includes: a dielectric layer under which a microstrip feedline is formed; a ground formed on the dielectric layer and electromagnetically coupled with the microstrip antenna through a slot; and a reflection plane placed under the microstrip feedline in order to prevent board surface waves from being radiated and enhance antenna gain.

Abstract: A microstrip patch antenna formed by using a microelectro-mechanical system technology is included. The microstrip patch antenna includes: a substrate provided with a ground formed on a bottom surface of the substrate; a feeding line formed on a top surface of the substrate for feeding an electric power; a coupling stub formed on the top surface of the substrate and electrically connected to the feeding line; a plurality of supporting posts erected on the top surface of the substrate; and a radiating patch formed on the supporting posts, thereby forming an area of air between the radiating patch and the top surface of the substrate.

Abstract: The present invention provides a microstrip patch antenna and array antenna using dielectric superstrate in order to enhance the antenna gain by stacking radiating patches and dielectric layers. The microstrip patch antenna using a dielectric superstrate for having high gain and wide bandwidth, includes: a lower patch antenna layer having a dielectric layer and a ground plane for radiating energy by exciting current by a feedline; a upper patch antenna layer having dielectric film electromagnetically coupled by the lower radiating patch; a foam layer for distancing the upper patch antenna layer from the lower patch antenna layer; and a dielectric superstrate located by being predeteremined distant from the upper patch antenna layer.

Abstract: A microstrip patch antenna formed by using a microelectro-mechanical system technology is included. The microstrip patch antenna includes: a substrate provided with a ground formed on a bottom surface of the substrate; a feeding line formed on a top surface of the substrate for feeding an electric power; a coupling stub formed on the top surface of the substrate and electrically connected to the feeding line; a plurality of supporting posts erected on the top surface of the substrate; and a radiating patch formed on the supporting posts, thereby forming an area of air between the radiating patch and the top surface of the substrate.

Abstract: The present invention provides a broadband slot array antenna that can be implemented with lower cost by using a single dielectric layer and a metal layer, and makes easy to implement an active integrated antenna. The broadband slot antenna includes: a dielectric layer under which a microstrip feedline is formed; a ground formed on the dielectric layer and electromagnetically coupled with the microstrip antenna through a slot; and a reflection plane placed under the microstrip feedline in order to prevent board surface waves from being radiated and enhance antenna gain.