Nihon Dempa Kogyo Co., Ltd.

Saga University

Other

Harada Kogyo Kabushiki Kaisha

Masayoshi Aikawa

Takayuki Tanaka

Fumio Asamura

Takeo Oita

Kenji Kawahata

Yoshimi Egashira

Eisuke Nishiyama

Katsuaki Sakamoto

Shigeru Egashira

Kazuhisa Yoshiki

Akihide Sakitani

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 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 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 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 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 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.

High-frequency oscillator

A planar circuit has a substrate, a planar circuit conductor disposed on a first main surface of the substrate, a ground conductor disposed on a second main surface of the substrate for creating a high frequency resonator based on an electromagnetic wave field in cooperation with the planar circuit conductor, and a circuit element disposed on an opening formed in at least one of the planar circuit conductor and ground conductor to electronically control the electromagnetic wave field. The circuit element may be a variable reactance element such as a varactor diode, or a switching element. The circuit element can variably control the electromagnetic wave field which defines the resonator, so that the resonator can be controlled, for example, to resonate at a variable frequency.

Planar circuit

A tri-band antenna including an center conducting an inner pipe surrounding the center conductor, an outer pipe surrounding the inner pipe and Teflon provided between the inner and outer pipes.

Growing community of inventors

Saga, Japan

Takayuki Tanaka