Abstract: An antenna includes a first arm whose one end is connected to a feeding unit, a second arm whose one end is connected to the first arm at a position that is away from the one end of the first arm and whose other end is connected to ground, and a variable impedance unit whose impedance is variable, provided between the ground and the other end of the first arm.

Abstract: The present invention relates to a tag-use antenna allowing a miniaturization while maintaining a constant minimal change of a communication distance. The tag-use antenna has a feed part of a folded dipole antenna of a size of 53 mm long and 7 mm wide being connected to, and equipped with, an LSI chip of Rc=500 ohms and Cc=1.4 pF and is covered with plastic resin 13 of the dielectric constant ?r=3 and thickness of t=0.75 mm on both sides of the antenna. The dipole part of 1 mm wire path width of the tag-use antenna is formed in a rectangular spiral by being bent inward from both ends at bending parts at four places. The entire length of the dipole antenna when extending the four bending parts straight is featured so as to be shorter than one half of a resonance wavelength of the antenna. An inductance part is formed in the neighborhood of the center of the dipole antenna, and placed in the middle of the dipole antenna, which is formed in said rectangular spiral, of the dipole antenna.

Abstract: An RFID tag includes a dielectric member, an antenna pattern formed on and around a surface of the dielectric member, and an IC chip that is electrically connected to the antenna pattern by means of two chip pads.

Abstract: An RF tag includes a first transmission line which is connected to a grounding conductor and forms an electric closed loop to constitute a dipole antenna. A power supply circuit is connected between a branch point on the first transmission line and the grounding conductor. A second transmission line is connected to the branch point and arranged in parallel with the power supply circuit to constitute an inductor.

Abstract: A tag device that performs high-quality radio communication without radio wave radiation or receiving characteristics being deteriorated near a person's body and without hindering communication by another IC tag. A main loop section sends and receives radio waves. The main loop section is a metal foil and has the shape of a long thin loop. The area of the main loop section is smaller than the area of a dielectric substrate. The main loop section covers part of surfaces of the dielectric substrate and part of sides of the dielectric substrate so as to put the dielectric substrate inside the loop. The main loop section is mounted in a horizontal direction of the dielectric substrate. Each of capacitive load sections is a metal foil and has a load corresponding to a capacitance component.

Abstract: A tag antenna is composed of a dielectric spacer, and an antenna pattern which is formed on one of surfaces of the spacer and has a size smaller than one half of a wavelength at an operating frequency, and in which a slit pattern suitable for the resistance and the capacitive components of a chip to be mounted is formed.

Abstract: An electromagnetic field simulation apparatus disclosed herein replaces a predetermined region in printed circuit board CAD data to be subjected to electromagnetic field simulation with measurement data measured by a near-field measurement device and generates new printed circuit board CAD data. Subsequently, regarding a measurement data portion in the new printed circuit board CAD data generated by the data generating unit, the electromagnetic field simulation apparatus generates analysis model data by setting, as a wave source, an electric field or a magnetic field measured by the near-field measurement device. Then, the electromagnetic field simulation apparatus executes electromagnetic field simulation with respect to the analysis model data having a set wave source.

Abstract: A loop antenna includes a dielectric substrate taking a cuboid form, and a loop part composed of a metal that covers two pairs of facing surfaces of the dielectric substrate. The loop part is formed by leaving a blank portion at the center of one surface of the pair of facing surfaces having a wider area. In the blank portion, a feeding point to an LSI chip and a capacitance part connected to the loop part in parallel to the feeding point are formed. The capacitance part is provided to compensate for an internal capacitance of the LSI chip so that a small LSI chip matches the antenna. A convex part having a length is arranged with a gap within a corresponding concave part to form a large capacitance.

Abstract: There is provided an antenna for tuning a resonant frequency. The antenna includes a first and a second arms connected to the antenna feeding portion at a common end thereof. The second arm has each of the plurality of branches including a switch for selecting a length of an electrical loop formed by the second arm and an end of a ground plane, each of the switches is connected to the ground plane. A first resonant frequency performed by the first arm is higher than a second resonant frequency by the second arm when each of the switches is open, and the first resonant frequency is lower than a third resonant frequency by the second arm when one of the switches is selected to connect the second arm and the ground plane so that the length of the electrical loop is maximum.

Abstract: A metal pipe includes a slot having a predetermined length in a longitudinal direction of the metal pipe and a wireless tag that is placed inside the metal pipe and includes a power feeding unit to feed electric power to the slot and an IC chip connected to the power feeding unit, thereby functioning as an antenna of the wireless tag. The metal pipe is thus managed by the wireless tag.

Abstract: A computer readable storage medium storing an electromagnetic field simulation program that causes a computer to execute receiving data defining, in virtual space, a shape of a conductor and an insulator included in a conductive layer and a dielectric layer of a printed circuit board; setting a plurality of cells in the virtual space by arranging nodes of the cells on a boundary between the conductive layer and the dielectric layer in a thickness direction of the printed circuit board and by arranging nodes of the cells at regular intervals in a plane parallel to the printed circuit board; giving, to each of the cells, an electric constant of a medium occupying an area of each of the cells; and determining a change over time in a an electromagnetic field strength in each of the cells.

Abstract: An antenna device includes a substrate, a pair of antenna elements formed on a face of the substrate and which is arranged so as to be axisymmetrical with respect to a symmetrical axis, and a ground section formed on the face of the substrate on which the pair of antenna elements is formed and which is arranged proximal to the pair of antenna elements, wherein the ground section is arranged so as to be axisymmetrical with respect to the symmetrical axis, and the ground section includes a first pair of slit sections notched from an end section and extending in one direction of the symmetrical axis.

Abstract: A wireless frequency tag includes a loop-shaped antenna pattern that is electrically connected to a chip connecting section, and a conducting member that electrically couples a part of the antenna pattern.

Abstract: A metal-resistant radio frequency tag that has a broader band pass band (frequency versus communication range) characteristic compared to conventional techniques is achieved. For this purpose, the radio frequency tag according to the present invention includes a first resonator pattern, the first resonator pattern including a chip connecting section to which a chip is to be connected, and an inductance section that is capable of adjusting an impedance matching with the chip; and a second resonator pattern that is fed through electromagnetic induction coupling via the inductance section.

Abstract: A tag patch antenna includes: a slit formed in the vicinity of an edge of an antenna pattern along a part of the edge; and a feeding point to which a tag LSI is connected and which is formed by cutting an intermediate portion of the part of the edge separated by the slit from a body of the antenna pattern by a width of the slit.

Abstract: The wireless tag includes an antenna conductor; a first power-supply conductor which is electromagnetic-inductively coupled with the antenna conductor; and a second power-supply conductor which is loop-shaped and which is electrically coupled with the first power-supply conductor.

Abstract: A loop antenna includes a dielectric substrate taking a cuboid form, and a loop part composed of a metal that covers two pairs of facing surfaces of the dielectric substrate. The loop part is formed by leaving a blank portion at the center of one surface of the pair of facing surfaces having a wider area. In the blank portion, a feeding point to an LSI chip and a capacitance part connected to the loop part in parallel to the feeding point are formed. The capacitance part is provided to compensate for an internal capacitance of the LSI chip so that a small LSI chip matches the antenna. A convex part having a length is arranged with a gap within a corresponding concave part to form a large capacitance.

Abstract: The simulating device and method that evaluates the intensity of radio waves including estimating a received power of a radio wave reaching an antenna of a radio tag having an IC chip connected with the antenna, calculating an impedance matching coefficient to use for matching an impedance of the antenna of the radio tag with an impedance of the IC chip of the radio tag, and adjusting the received power estimated with the use of the impedance matching coefficient calculated.

Abstract: A tag antenna which, within a limited area, resonates with an RFID LSI chip having a capacitance component, and an RFID tag on which such a tag antenna is mounted, and which has an antenna and an LSI chip connected in parallel to the antenna are disclosed; the antenna has a feed terminal connected to the LSI chip, a loop antenna connected to the feed terminal, and a bypass conducting path which bypasses the loop of the loop antenna.

Abstract: A dipole part of a length shorter than half of an antenna resonance wavelength is placed so as to be rolled and enables a feeding part 11 to feed a chip. An inductance part 12 for adjusting the inductance of the antenna is provided so as to sandwich the feeding part 11. The inductance 12 is provided using an empty space of the inside of the rolled dipole part. By providing the inductance part 12, the inductance of the antenna can be adjusted so as to resonate at a predetermined frequency with the capacitance of the chip connected to the feeding part 11. At this time, although the radiation resistance of the antenna becomes extremely large according to calculations, it is actually almost the same as the resistance of the chip due to loss, and the power received by the antenna can be provided to the chip.