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: 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: 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: 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: 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: A high-frequency circuit is formed on a multilayered dielectric substrate 1 having at least two conductive circuit layers. The high-frequency circuit includes: a first spiral conductive strip 4 formed in the first conductive circuit layer, the first spiral conductive strip having at least one turn; and a second spiral conductive strip 5 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.