Abstract: A log-periodic dipole array antenna according to one exemplary embodiment of the present disclosure includes a dielectric substrate, a radiating element having a plurality of lines extending from a center to an outer side and symmetrically arranged on the dielectric substrate based on the center, so as to resonate in a first frequency band and a second frequency band, the plurality of lines being connected at the center or the outer side of the radiating element in an alternating manner, the lines becoming longer going from up to down of the radiating element fed according to a predetermined log-periodic ratio, and a band stopper formed on one point for connecting the lines to each other.

Abstract: A log-periodic dipole array antenna according to one exemplary embodiment of the present disclosure includes a dielectric substrate, a radiating element having a plurality of lines extending from a center to an outer side and symmetrically arranged on the dielectric substrate based on the center, so as to resonate in a first frequency band and a second frequency band, the plurality of lines being connected at the center or the outer side of the radiating element in an alternating manner, the lines becoming longer going from up to down of the radiating element fed according to a predetermined long-periodic ratio, and a band stopper formed on one point for connecting the lines to each other

Abstract: The present invention relates to a radio frequency identification (RFID) tag antenna and an RFID tag, in which a connection part where a radiator dipole and a T-junction are connected has a branch structure, so that an electric current can be induced in the T-junction and the radiator dipole by the branch structure, and the amount of the electric current induced in the radiator dipole can be adjusted to thereby control impedance of the RFID tag antenna in detail. The RFID tag antenna includes: a substrate; a radiator dipole symmetrically printed on the substrate in a form of meanders; and a T-junction formed between the symmetrical radiator dipoles, formed integrally with each end part of the symmetrical radiator dipoles and performing impedance matching between the radiator dipole and an RFID tag chip, wherein a connection part where the symmetrical radiator dipole and the T-junction are connected has a branch structure.

Abstract: A multi-band internal antenna includes a top patch defining a first loop that defines a space therein and a first opening; a stub provided within the space defined by the first loop; a bottom patch provided below the top patch and having a first section and a second section connected to a feeder part and a shorting part, respectively, the bottom patch defining a second loop and second and third openings, the second and third openings being provided on opposing sides of the second loop so that the first and second sections of the bottom patch are separated from each other; and a first connecting part and a second connecting part connecting a first portion and a second portion of the top patch, respectively, to the first section and the second section of the bottom patch to transmit a signal from the bottom patch to the top patch.

Abstract: Provided is a multi-band internal antenna of a symmetry structure having stub, in which a size of the internal antenna can be reduced by stacking loop antennas, a broadband characteristic can be obtained in a high frequency band by connecting the stub to a top patch of the antenna, and a reduced SAR and an omni-directional radiation pattern can be obtained by configuring an antenna patch in a symmetry structure.