Abstract: According to one embodiment, a multiband filter includes a first resonator and a second resonator. The first resonator has a first capacitive component and a first inductive component. A signal of a first frequency is inputted to the first resonator. The second resonator has a second capacitive component and a second inductive component. A signal of a second frequency is inputted to the second resonator. The second frequency is different from the first frequency. A distance between a first capacitive component of the first resonator and a second capacitive component of the second resonator and a distance between a first inductive component of the first resonator and a second inductive component of the second resonator is longer than a shortest distance out of a distance between the first resonator and the second resonator. The capacitive components occur at the capacitance. The inductive components occur at the inductance.

Abstract: A superconducting antenna device of an embodiment includes an array antenna made by stacking a flat antenna having one or more antennas made of a superconducting material and a ground pattern on a low-loss dielectric substrate from a short wave band to an extremely-high frequency band, a vacuum chamber configured to accommodate the array antenna, a refrigerator configured to cool the array antenna, and a vacuum insulating window configured to pass an electromagnetic wave from a short wave band to an extremely-high frequency band in a direction of directivity of the array antenna in the vacuum chamber.

Abstract: A magnetic resonance imaging apparatus of an embodiment includes a housing, a static magnetic field source having a superconducting coil or a permanent magnet inside the housing, and a superconducting array antenna inside the housing.

Abstract: A superconducting antenna device of an embodiment includes an array antenna made by stacking a flat antenna having one or more antennas made of a superconducting material and a ground pattern on a low-loss dielectric substrate from a short wave band to an extremely-high frequency band, a vacuum chamber configured to accommodate the array antenna, a refrigerator configured to cool the array antenna, and a vacuum insulating window configured to pass an electromagnetic wave from a short wave band to an extremely-high frequency band in a direction of directivity of the array antenna in the vacuum chamber.

Abstract: A core-shell magnetic material having an excellent characteristic in a high-frequency band, in particular a GHz-band and a high environment resistance is provided. The core-shell magnetic material includes: a magnetic member in which plural core-shell magnetic particles are bound by a binder made of a first resin; and a coating layer that is made of a second resin different from the first resin, a surface of the magnetic member being covered with the coating layer. The core-shell magnetic material is characterized in that the core-shell magnetic particle includes a magnetic metallic particle and a covering layer that covers at least part of a surface of the magnetic metallic particle, the magnetic metallic particle contains at least one magnetic metal selected from a group consisting of Fe, Co, and Ni, and the covering layer is made of an oxide, a nitride, or a carbide that contains at least one magnetic metal.

Abstract: A superconducting filter device of an embodiment includes: a high-frequency filter includes a superconducting element, and a dielectric member; and a drive tool configured to adjust a distance between the superconducting element and the dielectric member. The dielectric member and the drive tool take both a connection state and a separation state.

Abstract: A filter of an embodiment includes: a microstrip-line planar filter that includes an input line, resonators, and an output line, and has a passband with a center frequency f0; a metal case housing the planar filter; and structural components that include dielectric components, the structural components arranged in the metal case at an interval in the traveling direction of electromagnetic waves from the input line to the output line or in a direction perpendicular to the wavefront of the standing waves generated by the electromagnetic waves resonating in the metal case, the interval being ? to ½ wavelength in terms of the electrical length of the center frequency f0.

Abstract: A filter according to embodiments includes n resonators, an input line, and an output line. Each of the resonators includes a first comb-like structure, a second comb-like structure, and a connection line that connect the first and the second comb-like structure. The first and second comb-like structures have a plurality of first lines and a second line that is connected to one end of the first lines. The first lines of the first and the second comb-like structures are arranged parallel to each other. The connection line has bending portions. Further, a second comb-like structure of a k-th resonator and a first comb-like structure of a (k+1)-th resonator are arranged so as to have an interlaced arrangement, and a second comb-like structure of the (k+1)-th resonator and a first comb-like structure of a (k+2)-th resonator are arranged so as to have an interlaced arrangement.

Abstract: A heat insulating transmission line includes a first waveguide with a first aperture end, a second waveguide with a second aperture end, and a reflector. The second waveguide is arranged coaxially with the first waveguide. The second aperture end faces the first aperture end through an air gap. The reflector is provided outside the air gap, and controls radiation power from the air gap. In addition, the reflector is substantially parallel to a portion of a virtual plane connecting an inner wall of the first aperture end of the first waveguide and an inner wall of the second aperture end of the second waveguide. When a mean frequency of a signal transmitting through the heat insulating transmission line is expressed as ?, a distance between the virtual surface and the reflector is not less than N×?/2?0.05? and not more than N×?/2+0.2? (N is a positive integer).

Abstract: A heat insulating transmission line includes a first waveguide with a first aperture end, a second waveguide with a second aperture end, and a reflector. The second waveguide is arranged coaxially with the first waveguide. The second aperture end faces the first aperture end through an air gap. The reflector is provided outside the air gap, and controls radiation power from the air gap. In addition, the reflector is substantially parallel to a portion of a virtual plane connecting an inner wall of the first aperture end of the first waveguide and an inner wall of the second aperture end of the second waveguide. When a mean frequency of a signal transmitting through the heat insulating transmission line is expressed as ?, a distance between the virtual surface and the reflector is not less than N×?/2?0.05? and not more than N×?/2+0.2? (N is a positive integer).

Abstract: A heat insulating transmission line includes a first waveguide with a first aperture end, a second waveguide with a second aperture end, and a reflector. The second waveguide is arranged coaxially with the first waveguide. The second aperture end faces the first aperture end through an air gap. The reflector is provided outside the air gap, and controls radiation power from the air gap. In addition, the reflector is substantially parallel to a portion of a virtual plane connecting an inner wall of the first aperture end of the first waveguide and an inner wall of the second aperture end of the second waveguide. When a mean frequency of a signal transmitting through the heat insulating transmission line is expressed as ?, a distance between the virtual surface and the reflector is not less than N×?/2?0.05? and not more than N×?/2+0.2? (N is a positive integer).

Abstract: A filter of an embodiment includes: a microstrip-line planar filter that includes an input line, resonators, and an output line, and has a passband with a center frequency f0; a metal case housing the planar filter; and structural components that include dielectric components, the structural components arranged in the metal case at an interval in the traveling direction of electromagnetic waves from the input line to the output line or in a direction perpendicular to the wavefront of the standing waves generated by the electromagnetic waves resonating in the metal case, the interval being ? to ½ wavelength in terms of the electrical length of the center frequency f0.

Abstract: The present invention provides a resonator and a filter that reduce the resonator radiation loss so as to achieve a high Q value that is inherent to a low-loss material while maintaining high power handling capability. In this manner, both high power handling capability and a high Q value can be achieved at the same time. The resonator is a microstripline structure and includes a line structure formed with resonance lines in which current standing waves are generated in a resonant state in a line, and currents in each two adjacent lines flow in the opposite directions from each other, and a connection line that connects the resonance lines at the portions having in-phase voltages among the nodes of the current standing waves of the resonance lines in the resonant state. The filter includes resonators of the same type as the above resonator.

Abstract: A core-shell magnetic material having an excellent characteristic in a high-frequency band, in particular a GHz-band and a high environment resistance is provided. The core-shell magnetic material includes: a magnetic member in which plural core-shell magnetic particles are bound by a binder made of a first resin; and a coating layer that is made of a second resin different from the first resin, a surface of the magnetic member being covered with the coating layer. The core-shell magnetic material is characterized in that the core-shell magnetic particle includes a magnetic metallic particle and a covering layer that covers at least part of a surface of the magnetic metallic particle, the magnetic metallic particle contains at least one magnetic metal selected from a group consisting of Fe, Co, and Ni, and the covering layer is made of an oxide, a nitride, or a carbide that contains at least one magnetic metal.

Abstract: There is provided with a filter circuit, including: an input terminal configured to input signals; a band stop filter configured to have a center frequency of input signals from the input terminal in a stop band and configured to reflect signals in the stop band that is included in the input signals and pass signals outside the stop band; a band pass filter configured to have a pass band including the stop band, and configured to pass signals in the pass band out of the signals having passed through the band stop filter; a synthesis circuit configured to synthesize the signals reflected on the band stop filter and the signals having passed through the band pass filter to obtain synthesis signals; and an output terminal configured to output the synthesis signals.

Abstract: According to an aspect of the present invention, there is provided a resonator including: a transmission line including a conductor line with a bent portion, wherein the conductor line has a plurality of slits formed therein, the slits being formed in an extending direction of the conductor line to pass through the bent portion, and wherein the slits are formed to have intervals that become narrower from an outer-side toward an inner-side of the bent portion.

Abstract: In resonant elements 102 to 105 constituting a resonant circuit, an uncontrolled cross coupling which exists between two resonant elements is controlled by using a coupling element 106 which is newly arranged between the resonant elements, whereby it is possible to create a state where two resonant elements are not coupled with each other or a state where the amount of the coupling is reduced, which states are difficult to be realized on a plane. As a result, it is possible to improve characteristics of a planar filter.

Abstract: A heat insulating transmission line includes a first waveguide with a first aperture end, a second waveguide with a second aperture end, and a reflector. The second waveguide is arranged coaxially with the first waveguide. The second aperture end faces the first aperture end through an air gap. The reflector is provided outside the air gap, and controls radiation power from the air gap. In addition, the reflector is substantially parallel to a portion of a virtual plane connecting an inner wall of the first aperture end of the first waveguide and an inner wall of the second aperture end of the second waveguide. When a mean frequency of a signal transmitting through the heat insulating transmission line is expressed as ?, a distance between the virtual surface and the reflector is not less than N×?/2?0.05? and not more than N×?/2+0.2? (N is a positive integer).

Abstract: The present invention provides a resonator and a filter that reduce the resonator radiation loss so as to achieve a high Q value that is inherent to a low-loss material while maintaining high power handling capability. In this manner, both high power handling capability and a high Q value can be achieved at the same time. The resonator is a microstripline structure and includes a line structure formed with resonance lines in which current standing waves are generated in a resonant state in a line, and currents in each two adjacent lines flow in the opposite directions from each other, and a connection line that connects the resonance lines at the portions having in-phase voltages among the nodes of the current standing waves of the resonance lines in the resonant state. The filter includes resonators of the same type as the above resonator.

Abstract: A multiplexer includes: a first band-pass filter for a first channel, which is formed in a microstrip line on a dielectric substrate and has a first branching characteristic having a center frequency of f1 and an attenuation pole at a frequency of fa1; and a second band-pass filter for a second channel, which is formed in a microstrip line on a dielectric substrate and has a second branching characteristic having a center frequency of f2 and an attenuation pole at a frequency of fa2. The following relationships (1) to (5) are satisfied: (1) f1<f2; (2) f1<fa1; (3) fa2<f2; (4) f2?fa1<(f2?f1)/2; and (5) fa2?f1<(f2?f1)/2. The second branching characteristic exhibits ?20 dB or less at the frequency of fa1 and the first branching characteristic exhibits ?20 dB or less at the frequency of fa2.