Abstract: An antenna device includes: a substrate; a radiating electrode formed on the substrate, a ground electrode formed on the substrate and disposed opposite the radiating electrode, a feed line as a distributed constant transmission line connected via a feed point to the radiating electrode, at least one impedance matching element for impedance-matching the radiating electrode at a prescribed signal frequency by being connected in parallel with the radiating electrode to the feed line at a position a prescribed distance away from the feed point, and a switch, interposed between the at least one impedance matching element and the feed line, for connecting or disconnecting the at least one impedance matching element to or from the feed line in accordance with a prescribed control signal.

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: An RFID tag having a tag antenna and an LSI chip, comprising: a power-supply pattern on which the LSI chip is mounted; a patch antenna that functions as the tag antenna; and a high-frequency connection section that makes a high-frequency connection between the power-supply pattern and the patch antenna. The high-frequency connection section is formed, for example, by forming a slot in the patch antenna, layering one end of a small dipole antenna that functions as the power-supply pattern over the slot so that it crosses over the slot, and supplying power from the small dipole antenna to the patch antenna.

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: There is provided an antenna device that includes a substrate, a slot provided in the substrate so that the slot includes a cut opening that is close to an edge of the substrate and the slot includes a crooked portion, a conductor section configured to include a slit in an area of the substrate, the area being sandwiched by the slot in the crooked portion, and an antenna that is placed close to the conductor section and is side by side with a surface of the substrate.

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: 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: An antenna device includes a feed element being of a length that allows resonance in a specified frequency band, a distributed constant feed line grounded at one end and coupled at another end to the feed element to form a feeding point, a reactive element grounded at one end and coupled at another end to a position a specified distance from the feeding point of the feed line, a first switch disposed between the feed line and the reactive element and used to select whether the feed line and the reactive element are coupled or uncoupled, a parasitic element disposed adjacent to the feed element and being of a length that allows resonance in a frequency band different from the frequency band in which the feed element resonates, and a second switch used to select whether the parasitic element is grounded.

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: An RF tag is disclosed that includes an antenna and an integrated circuit connected to the antenna. The antenna includes a first radiating element, a second radiating element, a feeding part connected in series between the first and second radiating elements, and an impedance control part connected parallel to the feeding part. An auxiliary radiating element connected to one or both of the first and second radiating elements is used for radio communication with the integrated circuit before completion of the RF tag, and is not used for radio communication after the completion of the RF tag.

Abstract: An RFID tag that has a tag antenna and a tag LSI comprising: a power-supply element in which the tag LSI is mounted on a power-supply section; a plurality of patch antennas that function as tag antennas and sizes differs; and a high-frequency coupling section that couples the power-supply element with each of the patch antennas by high-frequency coupling.

Abstract: An RFID tag having a tag antenna and an LSI chip, comprising: a power-supply pattern on which the LSI chip is mounted; a patch antenna that functions as the tag antenna; and a high-frequency connection section that makes a high-frequency connection between the power-supply pattern and the patch antenna. The high-frequency connection section is formed, for example, by forming a slot in the patch antenna, layering one end of a small dipole antenna that functions as the power-supply pattern over the slot so that it crosses over the slot, and supplying power from the smalI dipole antenna to the patch antenna.

Abstract: An antenna device includes an antenna element having an external form shaped into a substantially rectangular-shaped planar spiral coil and a switch provided to the antenna element.

Abstract: An RFID tag having a tag antenna and an LSI chip, comprising: a power-supply pattern on which the LSI chip is mounted; a patch antenna that functions as the tag antenna; and a high-frequency connection section that makes a high-frequency connection between the power-supply pattern and the patch antenna. The high-frequency connection section is formed, for example, by forming a slot in the patch antenna, layering one end of a small dipole antenna that functions as the power-supply pattern over the slot so that it crosses over the slot, and supplying power from the small dipole antenna to the patch antenna.

Abstract: A crossed dual tag includes two tags each of which comprises, on one plane, a dipole antenna formed with conductors, a feeding part to which an IC chip is connected at the center of the dipole antenna, and a loop-shaped inductance part that is formed between the dipoles of the dipole antenna and connected to the dipoles of the dipole antenna in parallel with respect to the feeding part. The two tags are crossed at right angles, and stacked to contact as closely as possible so that the loops of the inductance parts overlap as wide as possible. A reader/writer of an RFID system sequentially switches the surface of a circular polarized wave of a wireless signal between forward and backward directions, and reads information written to a user memory area from the tag that responds more strongly.

Abstract: An antenna apparatus, including: a substrate; an antenna element which is arranged on the substrate and transmits or receives a radio signal; a feed point which is connected to the antenna element and feeds a current or a voltage to the antenna element; and a wiring pattern, one end of which is connected to a ground pattern formed on a portion of the substrate, wherein two or more sets of the antenna element, the feed point, and the wiring pattern is included if the antenna element, the feed point, and the wiring pattern form one set.

Abstract: An RFID tag that has a tag antenna and a tag LSI comprising: a power-supply element in which the tag LSI is mounted on a power-supply section; a plurality of patch antennas that function as tag antennas and sizes differs; and a high-frequency coupling section that couples the power-supply element with each of the patch antennas by high-frequency coupling.

Abstract: An antenna device includes: a substrate; a radiating electrode formed on the substrate, a ground electrode formed on the substrate and disposed opposite the radiating electrode, a feed line as a distributed constant transmission line connected via a feed point to the radiating electrode, at least one impedance matching element for impedance-matching the radiating electrode at a prescribed signal frequency by being connected in parallel with the radiating electrode to the feed line at a position a prescribed distance away from the feed point, and a switch, interposed between the at least one impedance matching element and the feed line, for connecting or disconnecting the at least one impedance matching element to or from the feed line in accordance with a prescribed control signal.

Abstract: An antenna apparatus including: a first and second antenna elements which transmit or receive radio signal; a ground pattern; and a wiring pattern which is provided on a line segment connecting the first and second antenna elements, and directly connected to the ground pattern, wherein a circumventing path is formed by the wiring pattern and a part of the ground pattern.

Abstract: An antenna apparatus includes an antenna linear element including a linear conductor provided with a first end and a second end, a ground conductor connected to the linear conductor at the second end, a transmission line connected to the linear conductor at the first end, and a matching circuit including a first impedance adjustment element connected to the transmission line at an end on an opposite side to the end of transmission line connected to the linear conductor and a second impedance adjustment element which is connected to the first impedance adjustment element on an opposite side to the end of the first impedance adjustment element connected to the transmission line and an end of which on an opposite side to the end connected to the first impedance adjustment element is grounded, a connection part between the first impedance adjustment element and second impedance adjustment element receiving a power feed.