Abstract: An omnidirectional antenna is provided. The omnidirectional antenna includes a spiral antenna including a substrate, at least one upper antenna pattern formed on the substrate, and at least one lower antenna pattern formed under the substrate and connected to the upper antenna pattern; and a monopole antenna that supports the spiral antenna and that is connected to the spiral antenna. Therefore, by forming an omnidirectional antenna in a spiral antenna having an upper antenna pattern and a lower antenna pattern at an upper surface and a lower surface, respectively, of a substrate, three-dimensional current flow is available and thus omnidirectional radiation characteristics may be exhibited.

Abstract: An apparatus for wireless identification receives position information on recognition objects searched by a radar from the radar and identifies recognition objects within a communication area of antennas using signals responding to wireless frequency signals which are transmitted while changing beam directions of the antennas, for the recognition objects searched by the radar.

Abstract: An omnidirectional antenna is provided. The omnidirectional antenna includes a spiral antenna including a substrate, at least one upper antenna pattern formed on the substrate, and at least one lower antenna pattern formed under the substrate and connected to the upper antenna pattern; and a monopole antenna that supports the spiral antenna and that is connected to the spiral antenna. Therefore, by forming an omnidirectional antenna in a spiral antenna having an upper antenna pattern and a lower antenna pattern at an upper surface and a lower surface, respectively, of a substrate, three-dimensional current flow is available and thus omnidirectional radiation characteristics may be exhibited.

Abstract: A wireless communication method using a control channel between wireless communication devices including: exchanging profile information between a node and intermediate relay nodes therearound so as to allow the node to transmit/receive data to/from a destination node; determining, by the node, a first intermediate relay node using the profile information and determining a wireless communication mode with the first intermediate relay node; and transmitting/receiving data between the node and the first intermediate relay node by the determined wireless communication mode is provided.

Abstract: In a direction control antenna, a plurality of impedance elements are connected between a ground body and a radiator, a plurality of switches are connected between each impedance element and the ground body, and on/off of a plurality of switches is controlled according to a control instruction from the outside. In this case, by the turned-on switch, a radiation direction and a radiation form are determined according to short circuit positions of the radiator that is short-circuited to the ground body and the number of short circuit positions.

Abstract: A wireless communication method using a control channel between wireless communication devices including: exchanging profile information between a node and intermediate relay nodes therearound so as to allow the node to transmit/receive data to/from a destination node; determining, by the node, a first intermediate relay node using the profile information and determining a wireless communication mode with the first intermediate relay node; and transmitting/receiving data between the node and the first intermediate relay node by the determined wireless communication mode is provided.

Abstract: Provided are an apparatus and method for controlling a radiation direction. The apparatus includes parasitic elements disposed in proximity to the antenna, wherein each of the parasitic elements comprises an antenna; a first portion that is inclined with respect to a prepared ground surface at a first angle and a second portion that is inclined with respect to the first portion at a second angle; a lumped element having a variable reactance, which is disposed on each of the first and second portions; and a determination unit controlling the reactance of the lumped element so as to determine the radiation direction of the antenna. By using the apparatus and the method, the antenna has various radiation directions.

Abstract: Provided are an apparatus and method for controlling a radiation direction. The apparatus includes parasitic elements disposed in proximity to the antenna, wherein each of the parasitic elements comprises an antenna; a first portion that is inclined with respect to a prepared ground surface at a first angle and a second portion that is inclined with respect to the first portion at a second angle; a lumped element having a variable reactance, which is disposed on each of the first and second portions; and a determination unit controlling the reactance of the lumped element so as to determine the radiation direction of the antenna. By using the apparatus and the method, the antenna has various radiation directions.

Abstract: Provided are an impedance matching device of a sensor node and an impedance matching method of a sensor node. The impedance matching device comprises: a variable impedance matching unit disposed between a transmission unit, which is used for modulating a received signal to a radio frequency (RF) signal and outputting the RF signal, and an antenna and including a plurality of impedance matching circuits which have different impedance values from each other; a signal intensity measuring unit which measures the intensity of an output signal that is output through the variable impedance matching unit; and a control unit which controls one of the impedance matching circuits of the variable impedance matching unit to have an impedance value that maximizes the intensity of the output signal.

Abstract: A radiation patch having a shape of linearly-tapered rectangle for a planar inverted F antenna is disclosed. The planar inverted F antenna having a radiation patch includes: a ground unit for grounding a radiation patch; a short unit for shorting the radiation patch; a feeding unit for supplying an electric power to the radiation patch; and a radiation patch for radiating electric power from the feeding unit, wherein the radiation patch having a shape of linearly tapered rectangle and a length and width of tapered sides of radiation patch is determined according to a resonate frequency. As mentioned above, the present invention can be easier to be designed and provide wider bandwidth by providing a linearly tapered rectangle shape of radiation patch in a planar inverted F antenna.

Abstract: A radiation patch having a shape of linearly-tapered rectangle for a planar inverted F antenna is disclosed. The planar inverted F antenna having a radiation patch includes: a ground unit for grounding a radiation patch; a short unit for shorting the radiation patch; a feeding unit for supplying an electric power to the radiation patch; and a radiation patch for radiating electric power from the feeding unit, wherein the radiation patch having a shape of linearly tapered rectangle and a length and width of tapered sides of radiation patch is determined according to a resonate frequency. As mentioned above, the present invention can be easier to be designed and provide wider bandwidth by providing a linearly tapered rectangle shape of radiation patch in a planar inverted F antenna.