The Furukawa Electric Co., Ltd.

Furukawa Automotive Systems Inc.

Denso Corporation

Toshihide Fukuchi

Sadao Matsushima

Kei Takahashi

Kiyoshi Inoue

Yasushi Aoyagi

Shiro Koide

Yuji Nakagawa

Yoshiyuki Ishida

Ryuji Kohno

Sadao Matushima

A high-frequency circuit board capable of easily forming a bias line whose resonance frequency is sufficiently separated from operating frequency is provided. On a high-frequency circuit board, by electrically connecting a bias lineto a high-frequency circuitusing blind via holesand, it is possible to limit the route that has a possibility of producing resonance only to the bias line connecting the endsandof the blind via holesandto the bias line. By adjusting the route length from the endto the end, it is possible to prevent production of resonance in the vicinity of the operating frequency.

High-frequency circuit board

A radar device capable of removing noise signals before digital conversion and detecting an object with high precision by a simple configuration is provided. In a transmitting RF unit, a signal switchis switched so that the noise signal generated by the operation of a first switchpasses through a signal delaying device. The signal switchis switched so that the noise signal generated by the operation of a second switchpasses through a signal delaying device. Furthermore, the signal switchis switched so that a baseband pulse signal obtained when the first switchand the second switchare operated at the same time passes through a signal delaying device. In a signal synthesizer, synthesizing is carried out so that the noise signals mixed in pulse signals are cancelled out.

Radar device

There is provided an in-vehicle pulse radar that permits to detect information on an object accurately by temporally separating a noise signal mixed into a receiving signal by applying a delay time with a simple configuration. A baseband signal down-converted by a frequency converter () is output to a signal processing section () through a board-to-board connector () after passing through a delay circuit (). Still further, a control signal is output to a switching circuit () from a control signal generating section () through the board-to-board connector (). The delay circuit () increases a time lag from when the control signal passes through the board-to-board connector () until when the baseband signal passes through the board-to-board connector () by applying a predetermined delay time to the baseband signal. Thereby, the baseband signal receives no interference from the control signal.

In-vehicle pulse radar

A low noise amplification circuit comprises a low noise amplifier and a filter coupled to the input terminal of the low noise amplifier. The low noise amplifier comprises an amplifying element and a matching input circuit coupled to the input terminal of the amplifying element. When gamma.sub.s shows a reflection factor in the case that signals flow from the input terminal of the amplifying element to the output terminal of the matching input circuit, impedance conversion for setting the gamma.sub.s at a desired value is made entirely or in part by means of setting the output impedance of the filter at the value different from that of characteristic impedance.

Low noise amplification circuit

Growing community of inventors

Tokyo, Japan

Toshihide Fukuchi