Fujitsu Ten Limited

Fujitsu Corporation

Other

Osamu Isaji

Kanako Honda

Tamio Saito

Tetsuo Seki

Teruhisa Ninomiya

Kazuo Shirakawa

Naofumi Okubo

Naofumi Ohkubo

Yoshihiro Kawasaki

Hiroshi Kurihara

Hiroshi Suzuki

Yoji Ohashi

Nobukazu Shima

Masayoshi Shono

Hideki Kajioka

Norihiko Hatanaka

A radar apparatus includes a transmission section, a delay device, a reception section, a switch control section, a switching frequency detection section, and a relative distance calculation section. The transmission section transmits a signal wave, which is spectrum spread by using a spread code. The delay device gives delay to the spread code. The reception section receives a wave reflected by an object and spectrum despreads the reflected wave with using the delayed spread code to output a despread signal. The switch control section switches at a switching frequency an operation of at least one of the transmission section, the reception section, and the delay device. The switching frequency detection section detects the switching frequency from the despread signal. The relative distance calculation section calculates a distance to the object based on a detection result provided by the switching frequency detection section and an amount of the delay.

Radar apparatus

Provide an on-vehicle radar device that performs transmission control of a monitoring signal, following fixed rules, so that interference with other radar devices can be avoided with certainty. An on-vehicle radar device comprises a transceiver which transmits/receives a monitoring signal at a specified frequency band and transmits a priority order signal at a frequency within the above-mentioned frequency band, and a controller which switches the signals transmitted by the transceiver. The transceiver receives a priority order signal of another radar device, and when interference with the signal of the other radar device is detected, the controller, based on the priority order of that other device and on the priority order of the device itself, shifts, by a specified frequency amount, the frequency band of the monitoring signal transmitted by the transceiver.

On-vehicle radar device and on-vehicle radar device control system

Disclosed is a DBF radar apparatus comprising: an antenna for radiating a transmit signal; a plurality of antennas for receiving the transmit signal reflected from an object; a first selector switch section for sequentially selecting output terminals of the plurality of antennas one at a time for connection to an input terminal by performing switching with a first period; a first downconverting section for downconverting, by using a portion of the transmit signal, a received signal input from each antenna; a low-frequency cut-off filter connected to an output of the first downconverting section; a second selector switch section for connecting an output of the low-frequency cut-off filter to a sequentially selected one of a plurality of A/D converters; and a digital signal processing section for receiving outputs of the plurality of A/D converters, and for applying prescribed processing to the outputs to detect the distance to the object or the relative velocity with respect to the object, wherein, when each antenna is connected to the input terminal, the first selector switch performs on-off control with a second period shorter than the first period.

The invention is directed to reducing the number of high-frequency components in a phase monopulse radar. A received signal selected by alternately selecting two antennas by a first switch is amplified by a receiver amplifier and mixed in a mixer with a portion of a transmitter signal. Each beat signal output from the mixer is distributed via a second switch to a selected one of two processing systems.

The search/detection apparatus modulates a carrier signal by a modulation signal, generates a probe signal for detecting the location of a target, and receives the probe signal reflected by the target as an echo signal. Then, the search/detection apparatus detects the existence of an interference signal other than the echo signal from the received signal and modifies the parameter of the modulation signal and/or carrier signal.

Search/detection apparatus

In a radar apparatus constructed to perform switching between a plurality of receiving antennas by using a switch, the effect of noise induced by the antenna switching is eliminated. A situation where there is no echo signal from a target is created, for example, by turning off a transmitter amplifier, and the Fourier transformed result obtained at this time is taken as a correction value and stored in a memory. During radar operation, the effect of the noise induced by the antenna switching can be eliminated by subtracting the correction value from the Fourier transformed result.

The present invention relates to a radar apparatus that uses a plurality of transmitting/receiving antennas A-Aand receives a reflected wave, of a transmitted wave, reflected from a target. By utilizing the property that the path of the transmitted wave from an antenna Aand its reflected wave and the path of the transmitted wave from the next selected antenna Aand its reflected wave share the same spatial system, and therefore that both received signals have the same characteristics in terms of frequency and phase, a judgment is made as to whether there exists any difference between the receiving characteristics of the antennas, and the received signal is corrected in accordance with the result of the judgment. It is also possible to judge the presence or absence of a change in the characteristic of each antenna, and apply a correction accordingly, even during the normal operation of the apparatus.

In an FM-CW radar system, a frequency modulating said modulating wave output from said modulating signal generator has a frequency variation skew with respect to a time axis (modulation skew), and the radar system includes a means for varying the modulation skew by controlling the modulation frequency amplitude or modulation period of the modulating signal. The radar system further includes a means for discriminating a signal component varying in response to the variation of the modulation skew, thereby discriminating a signal related to a target object from other signals. In the case of an FM-CW radar system that performs transmission and/or reception by time division ON-OFF control the radar system includes a means for discriminating a signal which, when the frequency used to perform the ON OFF control is varied, varies in response to the variation of the frequency, thereby discriminating a signal related to a target object from other signals.

FM-CW radar system

In a radar apparatus, a receiving antenna includes a plurality of antenna elements, each receiving, as a reception signal, radio waves emitted into space and reflected off a target object. An analog signal is obtained by downconverting and putting a bandwidth constraint on the reception signal, and is then converted to a digital signal. Based on the digital signal, a signal processing unit detects the bearing of the target object. The signal processing unit performs processing based on outputs of two sets of the antenna elements.

The present invention relates to a radar device for forming multi-beams in multiple channels from reflected waves of a transmitted wave by using a minimum number of antennas. The device has: antennas used for both transmission and reception A&#x2013;A; transmission/reception switching meansof each antenna; a transmitter; and a receiverfor receiving the reflected waves of the transmitted wave. The ratio of the distance between adjacent antennas Aand Ato the distance between adjacent antennas Aand Aor Aand Ais 1:2. The transmitted signal is transmitted from each of the antennas selected sequentially and the received signal is processed by DBF in a signal processing controller, wherein eleven channels can be implemented by using four antennas and a space for six antennas.

Radar device capable of scanning received reflection waves

Disclosed is a radar apparatus equipped with a function for detecting an FM-AM conversion noise peak. When the direction of radiation is swept, any peak whose level remains substantially unchanged is judged to be a peak due to FM-AM conversion noise. Further, when FM modulation is stopped, any peak appearing in a region not lower than 50 kHz is judged to be a noise peak.

Radar apparatus equipped with abnormality detection function

In an FM-CW radar system, a frequency modulating wave output from said modulating signal generator has a frequency variation skew with respect to a time axis (modulation skew), and the radar system includes a means for varying the modulation skew by controlling the modulation frequency amplitude or modulation period of the modulating signal. The radar system further includes a means for discriminating a signal component varying in response to the variation of the modulation skew, thereby discriminating a signal related to a target object from other signals. In the case of an FM-CW radar system that performs transmission and/or reception by time division ON-OFF control, the radar system includes a means for discriminating a signal which, when the frequency used to perform the ON-OFF control is varied, varies in response to the variation of the frequency, thereby discriminating a signal related to a target object from other signals.

FM-CW radar system which discriminates between signals related to a target object and signals not related to a target object

A radar apparatus for a vehicle includes a casing, a correction member, and a selection indication. The casing includes a functional portion, which performs searching, and a reference surface. The correction member includes a plurality of correction surfaces. The selection indication indicates which one of the correction surfaces and the reference surface an attachment-direction adjustor is to be placed on during an attachment operation of the radar apparatus to the vehicle.

Radar apparatus for automobile, attachment direction adjuster and attachment direction adjusting method for radar apparatus

A radar mount direction alignment device to be used for aligning the transmit/receive direction of a radar deviceD mounted on a member on which a radar device is to be mounted, such as a vehicle. The radar mount direction alignment device has receiving sections b, bfor receiving a signal emitted from the radar deviceD, and transmission sections a, afor transmitting a signal to the radar deviceD. The radar mount direction alignment device has the function of emitting, toward the radar deviceD, a signal which, upon receipt of a signal output from the radar deviceD, behaves as if having been received at and reflected from a position farther from the radar deviceD than a distance between the radar deviceD and the radar mount direction alignment device.

Growing community of inventors

Kobe, Japan

Osamu Isaji