Abstract: 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 100, by electrically connecting a bias line 11 to a high-frequency circuit 10 using blind via holes 106 and 107, it is possible to limit the route that has a possibility of producing resonance only to the bias line connecting the ends 106a and 107a of the blind via holes 106 and 107 to the bias line 11. By adjusting the route length from the end 106a to the end 107a, it is possible to prevent production of resonance in the vicinity of the operating frequency.

Abstract: Provided is a quadrature demodulator capable of appropriately correct an amplitude error and a quadrature error even with respect to a pulse-modulated signal. In the quadrature demodulator 100, in order to compensate an amplitude error and a quadrature error, the phase adjuster 112 is provided in the local oscillation unit 110, and the quadrature detection error detector 131 and the quadrature detection error compensator 132 are provided in the signal processing unit 130. The quadrature detection unit 120 outputs two sets of I and Q-components of an RF signal using two LO signals that have been phase-shifted by the phase adjuster 112. In the quadrature detection error detector 131, an amplitude error and a quadrature error are calculated using the two sets of I and Q-components. The quadrature detection error compensator 132 compensates a received signal using the amplitude error and the quadrature error.

Abstract: 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 110, a signal switch 141 is switched so that the noise signal generated by the operation of a first switch 111 passes through a signal delaying device 142. The signal switch 141 is switched so that the noise signal generated by the operation of a second switch 112 passes through a signal delaying device 143. Furthermore, the signal switch 141 is switched so that a baseband pulse signal obtained when the first switch 111 and the second switch 112 are operated at the same time passes through a signal delaying device 144. In a signal synthesizer 145, synthesizing is carried out so that the noise signals mixed in pulse signals are cancelled out.

Abstract: 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 (152) is output to a signal processing section (102) through a board-to-board connector (103) after passing through a delay circuit (153). Still further, a control signal is output to a switching circuit (151) from a control signal generating section (162) through the board-to-board connector (103). The delay circuit (153) increases a time lag from when the control signal passes through the board-to-board connector (103) until when the baseband signal passes through the board-to-board connector (103) by applying a predetermined delay time to the baseband signal. Thereby, the baseband signal receives no interference from the control signal.

Abstract: 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 110, a signal switch 141 is switched so that the noise signal generated by the operation of a first switch 111 passes through a signal delaying device 142. The signal switch 141 is switched so that the noise signal generated by the operation of a second switch 112 passes through a signal delaying device 143. Furthermore, the signal switch 141 is switched so that a baseband pulse signal obtained when the first switch 111 and the second switch 112 are operated at the same time passes through a signal delaying device 144. In a signal synthesizer 145, synthesizing is carried out so that the noise signals mixed in pulse signals are cancelled out.

Abstract: 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 100, by electrically connecting a bias line 11 to a high-frequency circuit 10 using blind via holes 106 and 107, it is possible to limit the route that has a possibility of producing resonance only to the bias line connecting the ends 106a and 107a of the blind via holes 106 and 107 to the bias line 11. By adjusting the route length from the end 106a to the end 107a, it is possible to prevent production of resonance in the vicinity of the operating frequency.

Abstract: 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 (152) is output to a signal processing section (102) through a board-to-board connector (103) after passing through a delay circuit (153). Still further, a control signal is output to a switching circuit (151) from a control signal generating section (162) through the board-to-board connector (103). The delay circuit (153) increases a time lag from when the control signal passes through the board-to-board connector (103) until when the baseband signal passes through the board-to-board connector (103) by applying a predetermined delay time to the baseband signal. Thereby, the baseband signal receives no interference from the control signal.

Abstract: 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.

Abstract: 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.

Abstract: A radar device transmits an electric wave whose band is spread by a PN code, receives a reflected wave of the electric wave from an object 10, detects correlation between a received signal and a PN code which is delayed, and thereby detects the object. A receiving part 18 connects three receiving antennas 16a.about.16c sequentially one by one, thereby to receive a reflected wave from an object. The three receiving antennas are arranged having their directions so staggered that their antenna beam patterns partly overlap with each other. A correlation detection circuit 19 detects such a slide width that a value of correlation between a received signal received by each of the antennas and the PN code exceeds a predetermined threshold. An operation part 12 obtains an azimuth of an object based on the detected slide width and beam pattern characteristics of the antennas.