Abstract: An antenna according to the present invention includes a dielectric layer 102 with an upper surface and a lower surface, a signal line strip 101 provided on the upper surface of the dielectric layer 102, and a grounding conductor portion 104 provided on the lower surface of the dielectric layer 102. The surface of the grounding conductor portion 104 includes a plurality of planar areas, each of which has a size that is shorter than the wavelength of an electromagnetic wave to transmit or receive. A distance from a virtual reference plane to each planar area is adjusted on an area-by-area basis. Thus, an antenna, which can change various antenna parameters such as radiation directivity, gain and efficiency dynamically and adaptively according to incessantly changing propagation environment of radio wave, is provided.

Abstract: A slot antenna according to the present invention includes: a ground conductor 12 provided on a rear face side of a dielectric substrate 101, the ground conductor having a finite area; a slot 14 which recesses into the ground conductor 12, beginning from an open-end point on a side edge of the ground conductor 12; and a feed line 261 for supplying a high-frequency signal to the slot 14, the feed line 261 intersecting the slot 14. At a first point near the slot, the feed line 261 branches into a group of branch lines including at least two branch lines, such that at least two branch lines in the group of branch lines are connected to each other at a second point near the slot to form at least one loop line 209. A maximum value of a loop length of each loop line 209 is prescribed to be less than 1×effective wavelength at an upper limit frequency of an operating band of the slot antenna.

Abstract: Inside a multilayer dielectric substrate, there are a spiral-shaped first slot set in a part of a first ground conductor layer and a spiral-shaped second slot in a part of a second ground conductor layer put on the front surface of the multilayer dielectric substrate, the first slot and the second slot are opposite in a spiral winding direction and the first slot and the second slot overlap with each other as viewed from the top face, so that a resonance phenomenon can be produced at a frequency lower than a resonance frequency of a resonator with a conventional structure.

Abstract: In a radio-frequency device in which a dielectric layer, a first conductive layer and a second conductive layer are stacked one on another, the second conductive layer is including a plurality of conductive elements which are arrayed periodically and independently of one another at a specified array pitch, and a plurality of connecting elements for electrically connecting a plurality of mutually neighboring ones of the conductive elements to each other. The connection by the connecting elements is selectively made, thus making it possible to control radiation directivity of an electromagnetic field formed by the first and second conductive layers.

Abstract: A differential transmission line according to the present invention includes: a substrate 101; a ground conductor layer 105 formed on a rear side of the substrate 101; and a first signal conductor 102a and a second signal conductor 102b disposed in parallel to each other on a front side of the substrate 101. The first signal conductor 102a and the ground conductor layer 105 compose a first transmission line, whereas the second signal conductor 102b and the ground conductor layer 105 compose a second transmission line. The first transmission line and the second transmission line compose a differential transmission line 102c. The differential transmission line 102c includes a curved region 104a, with a straight region 104b being connected to each end of the curved region 104a.

Abstract: A differential transmission line according to the present invention includes: a substrate 101; a ground conductor layer 105 formed on a rear side of the substrate 101; and a first signal conductor 102a and a second signal conductor 102b disposed in parallel to each other on a front side of the substrate 101. The first signal conductor 102a and the ground conductor layer 105 compose a first transmission line, whereas the second signal conductor 102b and the ground conductor layer 105 compose a second transmission line. The first transmission line and the second transmission line compose a differential transmission line 102c. The differential transmission line 102c includes a curved region 104a, with a straight region 104b being connected to each end of the curved region 104a.

Abstract: A transmission line apparatus includes: a substrate 101 with a ground conductor plane; and first and second signal strips 102a, 102b supported on the substrate 101 in parallel with each other. The apparatus further includes at least one additional capacitance element 301 that connects the first and second signal strips 102a, 102b together. The element 301 includes: a first additional conductor 303 spaced from the first signal strip 102a; a second additional conductor 305 spaced from the second signal strip 102b; and a third additional conductor 307 connected to the first and second additional conductors 303, 305 at respective points. When measured in a signal transmission direction, the smallest width W3a of the third additional conductor 307 is shorter than the length L1 or L2 of the first or second additional conductor 303 or 305. And the additional capacitance element 301 has a resonant frequency that is higher than the frequency of a signal being transmitted.

Abstract: A high-frequency circuit is formed on a multilayered dielectric substrate having at least two conductive circuit layers. The high-frequency circuit includes: a first spiral conductive strip formed in the first conductive circuit layer, the first spiral conductive strip having at least one turn; and a second spiral conductive strip formed in a second conductive circuit layer which is different from the first conductive circuit layer, the second spiral conductive strip having at least one turn and not being in electrical conduction with the first spiral conductive strip. The first spiral conductive strip and the second spiral conductive strip, located at different levels, overlap each other. The first spiral conductive strip has a rotating direction opposite to a rotating direction of the second spiral conductive strip.

Abstract: An RF circuit component according to the present invention includes a waveguide 1 and at least one resonator 2, which is arranged inside the waveguide 1. The resonator 2 includes at least one patterned conductor layer, which is parallel to a plane that crosses an H plane, and resonates at a lower frequency than a cutoff frequency, which is defined by the internal dielectric constant, shape and size of the waveguide 1, thereby letting an electromagnetic wave, having a lower frequency than the cutoff frequency, pass through the inside of the waveguide 1.

Abstract: One transmission line includes a first signal conductor which is placed on one surface of a substrate formed from a dielectric or semiconductor and which is formed so as to be curved toward a first rotational direction within the surface, and a second signal conductor which is formed so as to be curved toward a second rotational direction opposite to the first rotational direction and which is placed in the surface so as to be electrically connected in series to the first signal conductor, wherein a transmission-direction reversal portion in which a signal is transmitted along a direction reversed with respect to a signal transmission direction of the transmission line as a whole is formed so as to include at least part of the first signal conductor and part of the second signal conductor. Such a transmission line is capable of obtaining a suppression effect of unwanted radiation intensity.

Abstract: In a transmission line pair including a first transmission line and a second transmission line which is so placed in adjacency that a coupled line region to be coupled with the first transmission line is formed, in the coupled line region, the first transmission line includes a first signal conductor which is placed on one surface which is either a top face of a substrate formed from a dielectric or semiconductor or an inner-layer surface parallel to the top face and which has a linear shape along its transmission direction, and the second transmission line includes a second signal conductor which is placed on the one surface of the substrate and which partly includes a transmission-direction reversal region for transmitting a signal along a direction having an angle of more than 90 degrees with respect to the transmission direction within the plane of the placement, and which has a line length different from that of the first signal conductor.

Abstract: A transmission line pair has two transmission lines placed adjacent to each other in parallel to a signal transmission direction of the transmission lines as a whole. Each of the transmission lines includes a first signal conductor which is placed on one surface of a substrate formed from a dielectric or semiconductor and which is formed so as to be curved toward a first rotational direction within the surface, and a second signal conductor which is formed so as to be curved toward a second rotational direction opposite to the first rotational direction and which is placed in the surface so as to be electrically connected in series to the first signal conductor. A transmission-direction reversal portion in which a signal is transmitted along a direction reversed with respect to the signal transmission direction of the transmission lines as a whole is formed so as to include at least part of the first signal conductor and part of the second signal conductor.

Abstract: Inside a multilayer dielectric substrate, there are a spiral-shaped first slot set in a part of a first ground conductor layer and a spiral-shaped second slot in a part of a second ground conductor layer put on the front surface of the multilayer dielectric substrate, the first slot and the second slot are opposite in a spiral winding direction and the first slot and the second slot overlap with each other as viewed from the top face, so that a resonance phenomenon can be produced at a frequency lower than a resonance frequency of a resonator with a conventional structure.

Abstract: A demultiplexer receives a multiplexed signal, in which a plurality of electrical signals with mutually different frequencies are multiplexed together, and divides the multiplexed signal into the electrical signals. The demultiplexer includes at least one line for propagating the multiplexed signal and a plurality of resonators arranged along the line. The dispersion characteristic of the line has a nonlinear portion, caused by electromagnetic coupling between the line and the resonators, and the phase velocities of the electrical signals which propagate through the line change according to their frequencies.

Abstract: In a radio-frequency device in which a dielectric layer, a first conductive layer and a second conductive layer are stacked one on another, the second conductive layer is including a plurality of conductive elements which are arrayed periodically and independently of one another at a specified array pitch, and a plurality of connecting elements for electrically connecting a plurality of mutually neighboring ones of the conductive elements to each other. The connection by the connecting elements is selectively made, thus making it possible to control radiation directivity of an electromagnetic field formed by the first and second conductive layers.

Abstract: A photonic crystal device according to the present invention includes: a first dielectric substrate 104 having a first lattice structure, of which the dielectric constant changes periodically within a first plane; a second dielectric substrate 105 having a second lattice structure, of which the dielectric constant changes periodically within a second plane; and an adjustment device (pivot 303) for changing a photonic band structure, defined by the first and second lattice structures, by varying relative arrangement of the first and second lattice structures. The first and second dielectric substrates 104 and 105 are stacked one upon the other.

Abstract: An RF circuit component according to the present invention includes a waveguide 1 and at least one resonator 2, which is arranged inside the waveguide 1. The resonator 2 includes at least one patterned conductor layer, which is parallel to a plane that crosses an H plane, and resonates at a lower frequency than a cutoff frequency, which is defined by the internal dielectric constant, shape and size of the waveguide 1, thereby letting an electromagnetic wave, having a lower frequency than the cutoff frequency, pass through the inside of the waveguide 1.

Abstract: Inside a multilayer dielectric substrate (1), there are a spiral-shaped first slot (4) set in a part of a first ground conductor layer (2) and a spiral-shaped second slot (5) in a part of a second ground conductor layer (3) put on the front surface of the multilayer dielectric substrate, the first slot and the second slot are opposite in a spiral winding direction and the first slot and the second slot overlap with each other as viewed from the top face, so that a resonance phenomenon can be produced at a frequency lower than a resonance frequency of a resonator with a conventional structure.

Abstract: An antenna according to the present invention includes a dielectric layer 102 with an upper surface and a lower surface, a signal line strip 101 provided on the upper surface of the dielectric layer 102, and a grounding conductor portion 104 provided on the lower surface of the dielectric layer 102. The surface of the grounding conductor portion 104 includes a plurality of planar areas, each of which has a size that is shorter than the wavelength of an electromagnetic wave to transmit or receive. A distance from a virtual reference plane to each planar area is adjusted on an area-by-area basis. Thus, an antenna, which can change various antenna parameters such as radiation directivity, gain and efficiency dynamically and adaptively according to incessantly changing propagation environment of radio wave, is provided.

Abstract: In a mobile body discrimination apparatus having an interrogator apparatus and a plurality of transponders each capable of transmitting information to the interrogator apparatus by modulation of radio waves that are reflected from a transponder antenna, which can be attached to respective articles, store data concerning the articles, and transmit the data to the interrogator apparatus in response to a command signal transmitted while the transponder traverses a communication region of an antenna of the interrogator apparatus, each transponder is configured to begin sending such response data after a randomly determined time interval following reception of the command signal, thereby reducing the probability of data conflict when plural transponders are within the communication region.