Nihon Dempa Kogyo Co., Ltd.

Other

Saga University

Masayoshi Aikawa

Fumio Asamura

Takeo Oita

Takayuki Tanaka

Eisuke Nishiyama

Kenji Kawahata

Katsuaki Sakamoto

Yoshifumi Kawamura

Kozo Egashira

A harmonic oscillator comprises a transmission line resonator in which an oscillation frequency depends on an electrical length of a transmission line and both ends of the transmission line are electrical open ends; an active element for oscillation as a negative resistance connecting to the transmission line resonator; an output line connected to a midpoint portion of the transmission line resonator; and electrical and/or physical suppressing means for suppressing a voltage displacement distribution of second harmonic among the even-order harmonics. The suppressing means is provided at a position which is at least a minimum voltage displacement portion for the second harmonic between the midpoint portion and either ends of the transmission line resonator.

Harmonic oscillator using transmission line resonator

A slot-line planar antenna has a substrate, an outer conductor disposed on one principal surface of the substrate and having an opening defined therein, an inner conductor disposed on the one principal surface of the substrate and positioned within the opening, the outer conductor and the inner conductor jointly defining a looped aperture line therebetween, and an electronic device electrically interconnecting the outer conductor and the inner conductor for controlling an electromagnetic wave field of a slot line provided by the aperture line.

Planar antenna with slot line

A push-push high frequency oscillator comprises a pair of amplifiers for oscillation, a loop-shaped microstrip line for connecting inputs of the pair of amplifiers to each other and connecting outputs of the pair of amplifiers to each other, a slot line disposed between the inputs and the outputs of the pair of amplifiers for electromagnetically coupling with the microstrip line, a nonlinear circuit for enhancing the level of harmonic components in an applied synchronization signal, a coupler circuit for electromagnetically coupling the output of the nonlinear circuit to the microstrip line, and a filter circuit disposed at the output of the nonlinear circuit. The filter circuit filters harmonic components of the synchronization signal such that the two oscillation systems are injected with the same frequency components as the fundamental wave or frequency components twice as high as the fundamental wave to increase frequency stability.

Injection locked high frequency oscillator

A planar harmonic high frequency oscillator comprises a pair of amplifiers for oscillation, a micro-strip line for connecting between inputs of the pair of amplifiers and between outputs of the amplifiers, a slot line disposed between the inputs and the outputs of the pair of the amplifiers for electromagnetically coupling with the micro-strip line, an output line connected to the micro-strip line at a position at which the micro-strip line traverses the slot line between the inputs or outputs of the pair of amplifiers, and an electronic device for connecting conductors on both sides of the slot line, and for controlling an electromagnetic wave field of the slot line in response to a control signal applied thereto. Two oscillation systems which oscillate in opposite phases with respect to the fundamental wave of oscillation are formed to generate an even-order harmonic of the fundamental wave.

Planar high frequency oscillator

A high frequency oscillator comprises a transmission line resonator having a midpoint which serves as a null potential point, a pair of active devices for oscillation respectively connected to a pair of mutually opposite-phase resonance wave points for the transmission line resonator, and a plurality of output lines each having one end connected to the transmission line resonator at a point symmetric to the midpoint, and the other end commonly connected to a connection. The pair of active devices share the resonator and oscillate in opposite phases to each other. The plurality of output lines are coupled to the transmission line resonator respectively at maximum displacement distribution points for a standing wave of an 2n-th harmonic in the transmission line resonator, where n is an integer equal to or larger than two. Even-order harmonic components of 2(n&#x2212;1)-th or lower are suppressed at the connection.

High frequency oscillator using transmission line resonator

A planar array antenna using a multi-layer substrate having an intermediate layer conductor in a laminated face comprises: four pieces of planar antenna elements disposed at each of geometrically square shaped apexes; first and second slot lines formed in the intermediate layer conductor, and intersecting each other; first to fourth microstrip lines formed along each side of geometrical squares so as to be coupled to each antenna element, and at the same time, electromagnetically coupled to first and second slot lines at both ends of these slot lines; and fifth and sixth microstrip lines, the top end sides thereof traversing the first and second slot lines, respectively, so as to be electromagnetically coupled to the first and second slot lines.

Planar array antenna

A high frequency oscillator has a substrate, a resonator circuit which is disposed on one principal surface of the substrate and consists of a closed loop-shaped slot line including an inner conductor and an outer conductor, an electric boundary point set on the slot line, a two-port negative resistance element for connecting between the inner conductor and outer conductor, and an output line electrically connected to the slot line. The electric boundary point is set by connecting, for example, a stub to the resonator circuit. The stub functions as an electrically short-circuited end or an electrically open end. A Gunn diode is preferably used for the negative resistance element, and inserted at a position of the slot line resonator circuit at which impedance matching is achieved.

Slot line based high frequency oscillator using two-port element

A planar array antenna comprises a powered antenna element and an adjacent passive element which are microstrip-line type ones and disposed on one principal surface of a dielectric substrate; and a feeding system for feeding high frequency power to the powered antenna element. The powered antenna element and a passive element disposed ahead of the powered antenna element constitute a powered element pair, and the adjacent passive element and a passive antenna element disposed ahead of the adjacent passive element constitute a passive element pair. The passive element pair is disposed so that it adjoins said powered element pair in an electric field direction or a magnetic field direction of radio wave emitted from the powered antenna element.

Microstrip line type planar array antenna

A multielement planar antenna has a substrate, a plurality of antenna element pairs disposed on a first main surface of said substrate, each of the antenna element pairs including first and second antenna elements each made of a circuit conductor, a metal conductor disposed on a second main surface of the substrate, and a slot line defined in the metal conductor. Each of the antenna element pairs has a microstrip line interconnecting the first and second antenna elements. The slot line crosses the microstrip lines and is electromagnetically coupled to the microstrip lines for feeding the first and second antenna elements. The slot line is fed at its central area by a microstrip line or a coplanar line.

Multielement planar antenna

A high frequency oscillator has a substrate made of, for example, a dielectric material, a resonator circuit disposed on one principal surface of the substrate and formed of a finite-length coplanar line having a signal line and a ground conductor arranged along the signal line on both sides thereof, a negative resistance element for connecting between the signal line and the ground conductor, and an output line routed on the other principal surface of the substrate and electromagnetically coupled to the resonator circuit through the substrate. A Gunn diode is preferably used for the negative resistance element, and is connected, for example, in a substantially central region of the signal line. The output line preferably forms a microstrip line structure together with the ground conductor.

Coplanar line based high frequency oscillator

A two-element slot line array antenna comprises a substrate having a first and a second main surface, a conductor disposed on the first main surface, a slot line formed in the conductor, and a pair of slot line antenna elements formed in the conductor. The slot line has one end side electromagnetically coupled to the pair of antenna elements, and the other end side serving as a feed end. The pair of antenna elements is arranged in parallel with an electric field plane or a magnetic field plane formed by the slot line. The pair of antenna elements and the slot line are arranged in mirror symmetry with respect to a magnetic field plane or electric field plane which starts at the feed end, so that the pair of antenna elements is excited in phase.

Two-element and multi-element planar array antennas

A high frequency oscillator suitable for implementing a push-push oscillator, a push-pull oscillator, and a four-phase push-push oscillator comprises a transmission line resonator, two active devices for oscillation connected to two resonant wave points, respectively, located on the transmission line resonator in an opposite phase relationship to each other, and a combiner line connected to an electric symmetric point of the transmission line resonator. The respective active devices constitute two oscillation systems, respectively, which share the transmission line resonator as a high frequency resonator. The combiner line combines outputs from the respective oscillation systems to generate a high frequency output.

A high-frequency filter for use in a superhigh frequency band such as of microwaves and millimeter waves has a substrate, a metal conductor disposed on a first main surface of the substrate, a resonator comprising a transmission line of a coplanar structure which is made of the metal conductor, and input and output lines disposed on a second main surface of the substrate transversely across the resonator and electromagnetically coupled to the resonator. The resonator may be a coplanar line resonator (coplanar waveguide resonator) or a slot line resonator. The high-frequency filter has a steep attenuating gradient in filter characteristics. The high-frequency filter may be combined with variable-reactance devices such as variable-capacitance diodes for electronically controlling the filter characteristics.

High-frequency filter

A multi-element planar array antenna has a substrate made of a dielectric material or the like; a planar conductor formed on a first principal surface of the substrate; a first and a second slot line formed in the conductor and intersecting each other; a first and a second microstrip line formed on a second principal surface of the substrate, and traversing the first slot line respectively at positions corresponding to both end sides of the first slot line; a third and a fourth microstrip line formed on the second principal surface, and traversing the second slot line respectively at positions corresponding to both end sides of the second slot line; and four slot line antenna elements formed on the first principal surface respectively in intersection regions between both end sides of the first and second microstrip lines and both end sides of the third and fourth microstrip lines.

Multi-element planar array antenna

A high-frequency oscillator includes: a substrate composed of a dielectric material; a first transmission line of coplanar structure which is arranged on one principal surface of the substrate; an amplifier having an input terminal and an output terminal and which is inserted into the first transmission line such that the input terminal and output terminal connect to the first transmission line; and a second transmission line which is provided on the other principal surface of the substrate, which electromagnetically couples with the first transmission line, and which constitutes a feedback circuit with respect to the amplifier. The first transmission line is typically a coplanar line of finite length, and the second transmission line is typically a microstrip line.

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Saga, Japan

Masayoshi Aikawa