Denso Corporation

Nippon Soken, Inc.

Nippondenso Co., Ltd.

Seishin Mikami

Masao Kodera

Katsuhiro Ohara

Toru Yamazaki

Kunihiko Sasaki

Shiro Koide

Masaaki Hisada

Ichiro Shigetomi

Shinji Fukui

Junshi Utsu

Akihiko Hayashi

Jyunshi Utsu

Yuji Yoshida

Junsi Utsu

A small antenna includes: a first element having a pair of conductors with a power feeding point; and a second element as a conductor arranged to sandwich a dielectric body. A part of the first and second elements has an inductance shape. A first resonance mode with a same current direction of the first element as the second element has a first resonant frequency. A second resonance mode with an opposite current direction of the first element to the second element has a second resonant frequency. A length from each power feeding point to the inductance shape is determined to hold the first resonant frequency within a range from a frequency slightly higher than the second resonant frequency to a high anti-resonant frequency of the second resonance mode, or a range from a frequency slightly lower than the second resonant frequency to a low anti-resonant frequency of the resonance mode.

Small antenna and calculation apparatus

A deformed folded dipole antenna includes: a feed-side parallel part; a non-feed side parallel part arranged to be parallel to the feed-side parallel part; and a pair of short circuit portions respectively connecting to both ends of the feed-side parallel part and both ends of the non-feed side parallel part. The non-feed side parallel part includes: a pair of opposite sides that are arranged to be opposite from each other; and a connecting side that connects one ends of the pair of opposite sides together. The feed-side parallel part includes a first L-shaped portion and a second L-shaped portion. At least one of the feed-side parallel part and the non-feed side parallel part has one portion arranged with an inward protruding part, which protrudes inwardly.

Deformed folded dipole antenna

An antenna is integrated with a solar battery. The antenna has a radiation-element portion arranged above the solar battery. The radiation-element portion is made of metallic wire rods and formed in a net-like fashion.

Antenna integrated with solar battery

In a U-shaped deformed folded dipole antenna, a first parallel section having a feeding point includes first and second L-shape sections, and a second parallel section without a feeding point includes first and second opposing side portions and a connecting side portion coupling ends of the first and second opposing side portions. Portions of the first and second L-shape sections arranged in parallel with the first and second opposing side portions have a width W. Portions of the first and second L-shape sections arranged in parallel with the connecting side portion have a width W. The first and second opposing side portions have a width W. The connecting side portion has a width W. An impedance of the deformed folded dipole antenna is controlled by setting the width Wto be larger than the widths W, W, and W

Deformed folded dipole antenna, method of controlling impedance of the same, and antenna device including the same

A vehicle-mounted antenna system includes a combined antenna apparatus that has a GPS antenna and a short-range wireless communication antenna. The GPS antenna is directional in a vertical direction and the short-range wireless communication antenna is directional in a horizontal direction. The combined antenna apparatus is mounted below an instrument panel of the vehicle by a mounting bracket in such a manner that the short-range wireless communication antenna is directional in the horizontal direction toward an interior of a vehicle. This approach ensures adequate performance of the short-range wireless communication antenna and standardizes a manner in which the short-range wireless communication antenna is mounted to the vehicle.

Vehicle-mounted antenna system

A planar antenna has a radiating element and a ground plate. A body of a vehicle has an internal edge that is formed by making a hole in the body. The planar antenna is located in the hole so that an imaginary plane of the internal edge is located between the radiating element and the ground plate. In such a structure, electric lines of force perpendicularly pass through the body beside the planar antenna. As a result, electric fields are maintained in the vertical direction even if the planar antenna is mounted on the vehicle. This maintains a horizontal directivity of the planar antenna.

Antenna apparatus and method for mounting antenna

An antenna device includes a ground plane, a first radiation element, and a second radiation element that is entirely disposed within the first radiation element. Of the first radiation element, a portion from a first end portion to a first bending portion electromagnetically couples with, of the second radiation element, a portion from a first end portion to a first bending portion. Further, of the first radiation element, a portion from a second end portion to a second bending portion electromagnetically couples with, of the second radiation element, a portion from a second end portion to a second bending portion. This structure enables the second radiation element to be resonant with the first radiation element.

Antenna device

In an antenna unit, a radiating element and an antenna ground element are held to a dielectric member, which is primarily provided for increasing electric lines of force passing from the radiating element to the antenna ground element. The radiating element and the antenna ground element are arranged with a predetermined slant relative to a circuit board. Therefore, the number of parts or the complexity of the assembly work for the antenna unit does not increase in comparison with an antenna unit holding a radiating element with an antenna base or a bracket. Furthermore, the slant can be adjusted to any angle during the assembly work. Thus, the maximum gain angle of the directional patterns can be adjusted without increasing the size of the antenna unit.

Antenna unit

A high-frequency amplifier has a semiconductor element for amplifying a high-frequency signal, an input matching circuit connected to an input side of the semiconductor element, and an output matching circuit connected to an output side of the semiconductor element. A stabilizing circuit is connected to at least one of a signal input path between the input matching circuit and the semiconductor element, and a signal output path between the semiconductor element and the output matching circuit. The stabilizing circuit includes a first element having a first end which is short-circuited with respect to a high frequency, a parallel resonant circuit connected in series with a second end of the first element and performing parallel resonance at an operating frequency of the high-frequency amplifier, and a second element connected to a side of the parallel resonant circuit which is opposite to the first element. Values of the first element and the second element are chosen so that an admittance of the high-frequency amplifier which occurs at a frequency of possible oscillation of the high-frequency amplifier will be within a constant-conductance circle in a Smith chart which denotes a stable condition of the high-frequency amplifier.

Circuit for stabilizing RF amplifier

Series reactance elements constituted by capacitors are connected to an input side corresponding to the gate electrode of an amplifying FET and an output side corresponding to the drain electrode of the amplifying FET, respectively. Parallel variable reactance circuits are connected to the input and output sides, respectively. Each variable reactance circuit includes a FET, where the source electrodes of the FET are connected to the input and output sides through MIM capacitors, respectively. Additionally, drain electrodes of the FETs are grounded through inductive loads which are constituted by spiral inductors, respectively. The source electrodes of the FETs constituting the variable reactance circuits are grounded through choke coils, respectively. The drain electrodes of the FETs receive control bias voltages through the choke coils, respectively. In this case, each of the resistive components of the spiral inductors is set to have a value which can cancel the negative resistive component of the corresponding FET.

Variable reactance circuit for microwave or millimeter wave band and

A Doppler radar speed detecting method in which periods of a Doppler signal are measured within a predetermined sampling time, and frequency data corresponding to the thus obtained period data are obtained. Upper and lower limit values are set based on the previous Doppler frequency F(k-1). The frequency data are compared with these limit values. Frequency data within a low region lower than the lower limit value, and intermedaite region between the lower and upper limit values, and a high region higher than the upper limit value are respectively counted in accordance with the comparison. Further, for the frequency data between the lower and upper limits, an integrated value of differences between these data and the previous Doppler frequency is obtained. From these integrated value and the numbers of frequency data, the change from the previous to the present Doppler frequency is calculated. By adding this change and the previous Doppler frequency together, the present Doppler frequency is obtained.

Doppler radar speed detecting method and apparatus therefor

In a planar array antenna in which radio frequency power fed by a feeder line is radiated from a plurality of radiation elements disposed in a planar state on one surface of a dielectric substrate on the other surface of which the feeder line is disposed, the feeder line has a first feeder part and a second feeder part. The first feeder part is spaced apart by a predetermined distance from the marginal contour of one of the radiation elements in the planar direction of the dielectric substrate, while the second feeder part is located within the width of the marginal contour of another one of the radiation elements and directly beneath the latter radiation element, and the second feeder part is divided into two parts with respective ends thereof confronting each other, the power coupling coefficient between the second feeder part and said another one radiation element is selected to be larger than that between the first feeder part and said one of the radiation elements, thereby making the planar array antenna operate with high radiation efficiency and small side lobes.

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Toyota, Japan

Seishin Mikami