Kabushiki Kaisha Toshiba

Tatsunori Hashimoto

Hiroyuki Kayano

Fumihiko Aiga

Mutsuki Yamazaki

Hiroyuki Fuke

Yoshiaki Terashima

Noritsugu Shiokawa

Tamio Kawaguchi

The present invention provides a filter circuit that can achieve both sharp bandpass characteristics and high power handling capability. The filter circuit includes: an input terminal that has a signal input; a four-port device that divides input signals; a band stop filter that has the center frequency of the input signals within the stopband, and causes the out-of-stopband signals among the input signals to pass; two bandstop resonators circuits that cause the signals passing through the band stop filters to pass, and reflect the signals; open ends that are connected in parallel to the two bandstop resonators circuits; and an output terminal that outputs the signals reflected by the band stop filters and the bandstop resonators circuits and combined at the four-port device.

Filter circuit and radio communication device

In resonant elementstoconstituting a resonant circuit, an uncontrolled cross coupling which exists between two resonant elements is controlled by using a coupling elementwhich 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.

Resonant circuit, filter circuit, and antenna device

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 fand an attenuation pole at a frequency of fa; 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 fand an attenuation pole at a frequency of fa. The following relationships (1) to (5) are satisfied: (1) f&#x3c;f; (2) f&#x3c;fa; (3) fa&#x3c;f; (4) f&#x2212;fa&#x3c;(f&#x2212;f)/2; and (5) fa&#x2212;f&#x3c;(f&#x2212;f)/2. The second branching characteristic exhibits &#x2212;20 dB or less at the frequency of faand the first branching characteristic exhibits &#x2212;20 dB or less at the frequency of fa

Multiplexer and wireless receiver

A superconductor filter comprises a plurality of resonance elements arranged between input-output lines formed on a substrate. Metal conductor sections serving to inhibit the spatial coupling between the adjacent resonance elements are arranged between prescribed resonance elements, and a prescribed resonance element is coupled with another resonance element by a coupling transmission line. It follows that each resonance element is coupled with another resonance element by the direct coupling via the coupling transmission line or by the spatial coupling via the space.

Superconductor filter

A band pass filter which is configured by a microstrip line, or a strip line is provided. The band pass filter has a first half wavelength resonator which resonates at a center frequency of a pass band, a second half wavelength resonator which resonates at the center frequency of the pass band, and a transmission line through which the first half wavelength resonator is wire-coupled to the second half wavelength resonator. A strong coupling can be stably realized without causing deviation of the resonance frequencies of resonators.

Band pass filter having resonators connected by off-set wire couplings

A filter circuit includes a plurality of resonators connected in parallel and each having loaded Q deviation equal to allowable deviation of a group delay, a divider to divide an input signal to the resonators, a combiner to combine output signals of the resonators, and an opposite phase unit for making signals passing two resonators of the resonators an approximately opposite phase in an output of the combiner, the two resonators having resonance frequencies adjacent to each other, respectively.

Filter circuit

A filter circuit has a complex block and exciting portions. The complex block has: a first block end resonator; a first resonator that is coupled to the first block end resonator; a second resonator that is coupled to the first resonator; a third resonator that is coupled to the second resonator; a fourth resonator that is coupled to the third resonator; and a second block end resonator that is coupled to the fourth resonator. Couplings between the first block end resonator and the second block end resonator, between the first resonator and the fourth resonator, and between the second resonator and the third resonator are in phase. The complex block and the exciting portions are single-path-coupled.

A band pass filter configured by a planar structure circuit, includes resonators of distribution constant circuit type, transmission line paths coupling the resonators and excitation lines arranged at input/output sides. The transmission line path is provided with line path portions coupling the resonators or the resonator and the excitation line. The line path portion have a length which is (1+2m)/4-fold (m: natural number) of a wavelength corresponding to a center frequency of the frequency band, and each coupling part between the resonators and the line portion has a length substantially determined as a &#xbc; wavelength.

Band pass filter

There is disclosed a half-wavelength (&#x3bb;/2) resonator which is constituted of a micro strip line or a strip line and in which line pattern portions are disposed symmetrically with respect to a reference line, connected to each other to form an L shape, and formed in an open loop shape so as to have open ends. For one pair of line pattern portions having the open ends, base portions connected to adjacent line pattern portions are disposed in the vicinity of the reference line, and the open ends are extended in opposite directions so that the ends are disposed apart from the reference line.

Resonator and filter

A high frequency filter having steep skirt characteristics using a sapphire R-plane substrate. The filter comprises a substrate having first and second faces. The first face is a sapphire R-plane. A grounded conductive layer is formed on the second face of the substrate. A pair of input/output terminals is formed on the first face. In embodiments, hairpin-shaped resonating portions are formed between the pair of input/output terminals. Each of the resonating portions has at least one long side. Each long side of the resonating portions makes an angle of &psgr; with <11-20> direction of a sapphire substrate. The angle &psgr; satisfies relations 0&deg;&lE;&psgr;&lE;30&deg;. In embodiments, the resonating portions are asymetric, J-shaped, or rectangular with an opening.

Growing community of inventors

Yokohama, Japan

Tatsunori Hashimoto