With Plural Receiver Frequency Band Separation Patents (Class 342/111)
  • Patent number: 10386482
    Abstract: A method, system and computer program product for tracking movement of an object, such as a hand. Speakers of a device to be controlled transmit frequency modulated continuous wave (FMCW) audio signals. These signals are reflected by the object and received by the microphones at the controlled device. The received and transmitted audio signals are mixed. A fast Fourier transform (FFT) is then performed on the mixed audio signals. One or more peak frequencies in the frequency domain of the FFT mixed audio signals are selected and used to estimate the distance between the object and the speakers of the controlled device. Furthermore, the velocity of the object is estimated. The coordinates of the object are then computed using the estimated distance between the object and the speakers and microphones of the controlled device and the estimated velocity of the object.
    Type: Grant
    Filed: January 24, 2017
    Date of Patent: August 20, 2019
    Assignee: Board of Regents, The University of Texas System
    Inventors: Lili Qiu, Sangki Yun
  • Patent number: 9991908
    Abstract: A blind source separation (BSS) system comprises means for gathering wideband signal power spectral information without using special Fourier transform hardware/software systems and without using extremely large signal memories. The method involves taking the combined energy output of a large set of BSS filters that are operating under a blind source separation algorithm that looks for signals of interest, along with instantaneous filter characteristics such as center frequency, bandwidth and spectral response, and records a weighted spread energy into a frequency- and time-based histogram. This information can then be used to compare against the BSS signal output and signal energy which does not correspond to existing signal output is added to additional BSS signal output. This system can operate in real time, but uses long-term averaging to enhance signal detection.
    Type: Grant
    Filed: September 21, 2016
    Date of Patent: June 5, 2018
    Assignee: The Boeing Company
    Inventor: Gary A. Ray
  • Patent number: 9581682
    Abstract: Disclosed herein is a frequency modulated continuous wave (FMCW) radar device, including: a continuous wave (CW) signal generator configured to generate a transmit (Tx) CW signal; a radio frequency (RF) transmitter configured to transmit the generated Tx CW signal as an RF signal through a Tx antenna; an RF receiver configured to receive a CW signal which is reflected and returned from a forward object after the Tx CW signal is transmitted; a target detector configured to extract speed and angle using a frequency difference between the Tx CW signal and the reflected CW signal, and detect an approaching target; and a detection controller configured to control the RF transmitter to transmit the Tx CW signal as a signal having a triangular waveform in a time-frequency graph and to additionally transmit the Tx CW signal as a signal having a crossbar waveform at a predetermined frequency for a predetermined time, and extract speed and angle from the reflected CW signal having a crossbar waveform so as to detect th
    Type: Grant
    Filed: July 3, 2014
    Date of Patent: February 28, 2017
    Assignee: MANDO CORPORATION
    Inventors: Seong Hee Jeong, Jae Eun Lee
  • Patent number: 9322696
    Abstract: Provided is an apparatus for measuring a level of molten metal which has a simple structure and is highly robust against a change in level at a local portion of the surface of molten metal. The apparatus for measuring a level of molten metal according to a first aspect of the present invention is an apparatus which measures a level of molten metal in a mold. The apparatus includes an omnidirectional transmitting antenna; an omnidirectional receiving antenna; and a signal processor. The apparatus measures the level of molten metal in the mold using electromagnetic wave in ultra-high frequency range emitted into the mold by the omnidirectional transmitting antenna.
    Type: Grant
    Filed: December 9, 2013
    Date of Patent: April 26, 2016
    Assignee: NIRECO CORPORATION
    Inventors: Koichi Matsumoto, Yasumasa Kato
  • Patent number: 8731123
    Abstract: A demultiplexing device that includes frequency-conversion and reception low-pass-filter units that perform a frequency converting process and a low-pass filtering process for causing a signal to pass through a desired band, perform downsampling to reduce a sampling rate to half of a data rate of an input signal, and output the signal, reception channel-filter units that waveform-shape a signal with a desired frequency characteristic and output the waveform-shaped signal. The demultiplexing device also includes a filter-bank control unit that generates a clock control signal for supplying a clock to frequency-conversion and reception low-pass-filter units and reception channel-filter units corresponding to signal passage bands, based on channel information, and a reception-clock supply unit that supplies a clock to frequency-conversion and reception low-pass-filter units and reception channel-filter units corresponding to signal passage bands, based on the clock control signal.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: May 20, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventor: Akinori Fujimura
  • Patent number: 8648746
    Abstract: A network analyzer includes an n-port network with two ports for measuring wave parameters of a measurement object. Each port has a feed for a radio-frequency signal from a signal source. Signal components of the radio-frequency signal fed into the respective port are reflected at the measurement object and the signal components of one or more radio-frequency signals fed into at least one other port are transmitted through the measurement object to the respective port are measured as wave parameters. The two ports are supplied with different radio-frequency signals, wherein frequencies or frequency bands are offset with respect to one another by a frequency offset. Reflected and transmitted signal components of the radio-frequency signals are measured at the same time at the two ports.
    Type: Grant
    Filed: February 25, 2010
    Date of Patent: February 11, 2014
    Assignee: Siemens Aktiengesellschaft
    Inventors: Florian Poprawa, Andreas Schicht, Claus Seisenberger, Andreas Ziroff
  • Patent number: 8427361
    Abstract: The radar apparatus includes a target candidate detecting means for detecting a peak frequency at which the intensity of the power spectrum of a beat signal peaks as a target candidate, a road shape recognizing means to sequentially connect, along a predetermined direction, the target candidates detected to be stationary and present within a reference distance from one of the target candidates set as a reference target candidate for one or more measurement cycles and recognize an area formed by the sequentially connected target candidates as an edge of the road, a cruise environment estimating means to determine whether the cruise environment is a closed space or an open space based on the power spectrum, and a reference distance correcting means to shorten the reference distance when the cruise environment is determined to be a closed space.
    Type: Grant
    Filed: September 6, 2011
    Date of Patent: April 23, 2013
    Assignee: Denso Corporation
    Inventor: Koichi Sato
  • Patent number: 8305256
    Abstract: A radar system achieves unambiguous target range at a given PRI, in conjunction with unambiguous Doppler, by transmitting CW-LFM pulses and then separating the return signal into subpulses, without requiring any modifications to the transmit waveform. The CW-LFM pulses may be contiguous. The return signals are bandpass-filtered to generate the subpulses, and downconverted to a common frequency such as baseband. Each downconverted subpulse is matched-filtered to the FM slope, and the resulting matched-filtered subpulses are time-aligned. The time-aligned subpulses are Doppler-filtered to determine target velocity.
    Type: Grant
    Filed: February 9, 2010
    Date of Patent: November 6, 2012
    Assignee: Lockheed Martin Corporation
    Inventors: Arul Manickam, Gregory P. Fonder
  • Patent number: 8238472
    Abstract: One or more carrier signals in a multiple-carrier UE transmitter are frequency-adjusted to account for an estimated error in the separation frequency between the transmitted carrier signals. The adjustment is applied when generating the UL signals for the respective carrier frequencies in digital baseband of the UE. In one embodiment, one or more of the modulators that apply the carrier separation frequency additionally apply a frequency correction. In another embodiment, first mixers apply the carrier separation frequency to each different carrier signal. One or more carrier signal paths include a second mixer applying a frequency correction to the carrier signal. The RF modulation frequency may also be adjusted to partially compensate for the estimated carrier separation frequency error.
    Type: Grant
    Filed: April 7, 2009
    Date of Patent: August 7, 2012
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Oskar Drugge, Anders Wallén
  • Patent number: 8179303
    Abstract: A signal processing apparatus for a radar transceiver, which receives a reflected signal generated by a target object in response to a frequency modulated transmission signal, and generates a beat signal having a frequency difference between the transmission signal and a reception signal, includes: an azimuth angle detection unit that detects an azimuth angle of the target object on the basis of a peak signal in a frequency spectrum of the beat signal; a peak signal extraction unit that prioritizes extraction of a peak signal corresponding to a predetermined azimuth angle range and a predetermined relative distance range of the target object; and a target object detection unit that detects the target object from the extracted peak signal.
    Type: Grant
    Filed: August 5, 2009
    Date of Patent: May 15, 2012
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masayuki Kishida, Hisateru Asanuma, Tomoya Kawasaki
  • Patent number: 7893868
    Abstract: A radar device is mounted on a vehicle, for detecting an object, and includes: a transmitting unit for transmitting an electromagnetic wave as a transmitter signal; a receiving unit for receiving a reflected signal that is reflected from the object as a receiver signal; a signal processing unit for measuring a distance and a relative velocity between the vehicle and the object on the basis of a beat signal that is obtained by the transmitter signal and the receiver signal; and an interference detecting unit for detecting the interference signal from another radar device or a communication device on the basis of a signal intensity of the frequency range that is not used for measuring the distance to the object and the relative velocity of the object.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: February 22, 2011
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenichi Akita, Kado Nakagawa
  • Patent number: 7884756
    Abstract: A radar apparatus measures an azimuth angle with a calculation device that performs super-resolution angle measuring processing in which relative speeds and relative distances among target objects are calculated, when two azimuth angles are obtained for a given target object that has been detected, the calculation device performs an other-signal detection processing in which, among other detected target objects, a target object is searched whose azimuth angle is the same as one of the two azimuth angles and whose beat frequency upon frequency-increasing modification or frequency-decreasing modification is the same as that of the given target object; and when, through the other-signal detection processing, another target object that satisfies the condition is detected, the calculation device eliminates one of two azimuth angles of the detected given target object, which is equal to the azimuth angle of said another target object detected through the other-signal detection processing.
    Type: Grant
    Filed: February 25, 2009
    Date of Patent: February 8, 2011
    Assignee: Mitsubishi Electric Corporation
    Inventor: Koichi Kai
  • Patent number: 7782245
    Abstract: A scanning radar system suitable for detecting and monitoring ground-based targets includes a frequency generator, a frequency scanning antenna, and a receiver arranged to process signals received from a target so as to identify a Doppler frequency associated with the target. The frequency generator generates sets of signals, each set having a different characteristic frequency, and includes a digital synthesiser arranged to modulate a continuous wave signal of a given characteristic frequency by a sequence of modulation patterns to generate one set of signals. The frequency scanning antenna cooperates with the frequency generator to transceive radiation over a region having an angular extent dependent on the generated frequencies.
    Type: Grant
    Filed: July 15, 2009
    Date of Patent: August 24, 2010
    Assignee: Plextek Limited
    Inventors: Graham Pearson, Steve Greendale, David Spreadbury
  • Patent number: 7755536
    Abstract: The present invention is a method of finding range and velocity of a target in a radar system using a time scale factor. Specifically, sending at least one signal from at least one transmitter to a target. A return signal is then received from the target at each transmitter and the elapsed time is recorded. The range to the target and velocity of the target are calculated based on a time scale factor of the recorded elapsed times. These values are appropriately output to the user.
    Type: Grant
    Filed: February 6, 2007
    Date of Patent: July 13, 2010
    Assignee: The United States of America as represented by the Director, National Security Agency
    Inventors: Douglas J. Nelson, David C. Smith
  • Patent number: 7755535
    Abstract: A radar system comprising at least two spatially separated antenna units, each comprising one antenna. Each antenna unit comprising a signal generator connected to an antenna constitutes a transmitting antenna unit, and each antenna comprising a receiver connected to an antenna constitutes a receiving antenna. At least one receiving antenna unit is arranged for receiving at least one reflected signal, comprising signals transmitted from at least one transmitting antenna unit, having been reflected from at least one object, where the number of antenna units exceeds two. A processing unit is arranged to perform a correlation calculation, comparing at least one received signal with a set of mathematically manipulated copies. From said set, there is only one match for each reflected signal. The present invention also relates to corresponding methods.
    Type: Grant
    Filed: February 9, 2006
    Date of Patent: July 13, 2010
    Assignee: Telefonaktiebolaget LM Ericsson (Pub)
    Inventor: Kent Falk
  • Patent number: 7567202
    Abstract: Embodiments of the invention are concerned with a radar system, and relates specifically to scanning radar systems that are suitable for detecting and monitoring ground-based targets.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: July 28, 2009
    Assignee: Plextek Limited
    Inventors: Graham Pearson, Steve Greendale, David Spreadbury
  • Patent number: 7504990
    Abstract: 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 a
    Type: Grant
    Filed: January 14, 2005
    Date of Patent: March 17, 2009
    Assignee: Fujitsu Ten Limited
    Inventor: Osamu Isaji
  • Patent number: 7495604
    Abstract: A sampled beat signal is cut out into two or more short time data in a time direction concerning each antenna component. From a frequency spectrum of the short time data, an interference element frequency of an interference wave is detected. From the interference element frequency of the interference wave, two or more candidates of the frequency before aliasing of the interference wave are produced, and phase correction is executed on each candidate. Digital Beamforming is executed on the corrected frequency so as to extract maximum peaks of the power of an azimuth direction, and the frequency candidate showing the maximum peak power is selected and the arrival azimuth of the interference element is estimated. A filter for suppressing the interference element is applied on the short time data from the estimated arrival azimuth of the interference element so as to suppress the interference element.
    Type: Grant
    Filed: February 20, 2007
    Date of Patent: February 24, 2009
    Assignee: Denso Corporation
    Inventors: Chiharu Yamano, Kazuma Natsume, Yuu Watanabe, Mai Sakamoto
  • Patent number: 7489266
    Abstract: A radar system comprises: a plurality of reception antennas; a transmission wave generating device; a transmission antenna; a mixer; an A/D converter; a storage device which stores the digitized beat signals in association with each of the reception antennas; a Fourier transformation device which Fourier transforms the stored beat signals; a digital beam forming device which generates beam signals at predetermined pitch angles based on the Fourier transformed signals; an orientation detecting device which detects an orientation of the object using the generated beam signals; a distance detecting device which detects a distance to the object using the generated beam signals; and a signal separation processing device which performs separation processing of the beat signals based on the detected orientation and distance of the object, using the beat signals associated with each of the reception antennas, which are Fourier transformed by the Fourier transformation device.
    Type: Grant
    Filed: March 28, 2006
    Date of Patent: February 10, 2009
    Assignees: Honda Elesys Co., Ltd., Honda Motor Co., Ltd.
    Inventors: Kensuke Ohtake, Manabu Hirao, Masahito Shingyoji, Hiroyuki Ando
  • Patent number: 7352320
    Abstract: An FM-CW radar includes a transmitting section, a mixing section, an A/D conversion section, a storage unit, and a signal processing section. The transmitting section transmits a continuous wave frequency-modulated with a triangular wave. The mixing section mixes the continuous wave transmitted and a reflected wave from a target, to generate a beat wave. The A/D conversion section A/D converts the beat wave into digital data. The storage unit includes a first storage section and a second storage section. The signal processing section reads data from the first storage section to process the read data. The A/D conversion section writes the digital data into the second storage section. The control section switches the first storage section and the second storage section alternately in synchronous with switching between up and down of the triangular wave.
    Type: Grant
    Filed: May 27, 2005
    Date of Patent: April 1, 2008
    Assignee: Fujitsu Ten LImited
    Inventors: Daisuke Enomoto, Yukio Ishikawa
  • Patent number: 7339518
    Abstract: An FMCW radar device executes a frequency analysis for a beat signal in a frequency increase interval and a frequency decrease interval, to obtain frequency components in a predetermined high frequency range exceeding a frequency range corresponding to a target detection frequency range within which a target object for detection should be detected. Then the FMCW radar device calculates a value related to a sum of intensities of frequency components within the high frequency range respectively for each of the frequency increase interval and the frequency decrease interval. In the case that one of the calculated integrals is larger than a threshold, the FMCW radar device determines that the FMCW radar device is interfered with by a nearby radar device.
    Type: Grant
    Filed: February 10, 2006
    Date of Patent: March 4, 2008
    Assignee: DENSO Corporation
    Inventors: Kazuma Natsume, Yuu Watanabe
  • Patent number: 7336218
    Abstract: A radar system in which a beat signal is generated by transmitting a transmission signal that is subjected to frequency modulation into a triangular wave and receiving a reflection signal from a target, the beat signal is sampled, and a window function is applied to yield a discrete frequency spectrum. When the window function is applied, a first window function having an amplitude that is gently attenuated from the center of the sampling period toward both sides thereof is applied in a lower frequency band in the frequency spectrum (at close range), and a second window function having an amplitude that is sharply attenuated from the center of the sampling period toward both sides thereof is applied in a higher frequency band in the frequency spectrum (at far range).
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: February 26, 2008
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Tetsu Nishimura, Toru Ishii
  • Publication number: 20070222670
    Abstract: A measuring apparatus for measuring a distance from an object to be measured has, a transmitting means for alternately modulating amplitudes of a first continuous wave having a first frequency and a second continuous wave having a second frequency for transmitting a transmission signal as a carrier wave using an AM signal. The AM signal is produced by an AM producing circuit for modulating the amplitudes. The transmission signal is reflected as a reflection signal by the object to be measured and received by a receiving circuit. A first distance calculating circuit calculates the distance using a phase difference between the first and second continuous waves. A second distance calculating circuit is used for demodulating the receipt signal, detecting a phase difference, and calculating a distance from the object to be measured using the detected phase difference. A determining circuit determines a final distance measurement based on the above calculations.
    Type: Application
    Filed: March 23, 2007
    Publication date: September 27, 2007
    Applicant: OMRON Corporation
    Inventors: Shinya Takenouchi, Hoshibumi Ichiyanagi, Yasuhiro Satoh
  • Patent number: 7184493
    Abstract: Disclosed is a real-time pulse sorting apparatus of a preprocessor in a pulsed radiation detection system. The apparatus, responsive to digital signals generated by a system receiver, uses the instantaneous frequency as the address input to store discrete data groups in main memory. Each data group, comprising the digital data corresponding to a single analog-to-digital converter sample point, includes the RF signal amplitude, inter-channel phase difference, instantaneous frequency as well as a unique pulse number generated by the pulse sorting apparatus. The present invention further includes a TOA memory for storing the time-of-arrival of each pulse at an address given by the pulse number. The main memory, organized in the form of a frequency-based histogram, together with the TOA memory, linked to the main memory by means of the pulse number pointer, sorts and records RF signal data with minimal processor control and intervention.
    Type: Grant
    Filed: October 15, 2002
    Date of Patent: February 27, 2007
    Assignee: Alliant Techsystems Inc.
    Inventors: Richard Charles Pringle, Joanna S. Quan
  • Patent number: 7136013
    Abstract: In a radio wave radar system using a two-frequency CW modulation method, it is possible to detect a distance between a host vehicle and a forward vehicle and to realize a stable ACC following travel, even in a condition in which the relative speed is 0. By combining the two-frequency CW modulation method with the frequency pulse CW modulation method, that is, by using combination with the two-frequency CW method when the relative speed occurs and the frequency pulse CW method when the relative speed is close to 0, even if the relative speed is 0, the IF signal obtained from the reflected wave from the forward vehicle can be generated to detect the existence of the ACC target vehicle, so that it is possible to realize a stable ACC following travel.
    Type: Grant
    Filed: July 24, 2003
    Date of Patent: November 14, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiko Hanawa, Hiroshi Kuroda, Kazuaki Takano
  • Patent number: 7079030
    Abstract: A microwave sensor transmits a plurality of microwaves having different frequencies to a detection area and performs an object detecting operation based on reflected waves of the microwaves of an object present in the detection area. The microwave sensor includes object determining means that determines whether or not the object present in the detection area is an object to be detected, based on a moving direction of the object in the detection area.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: July 18, 2006
    Assignee: Optex Co., Ltd.
    Inventor: Masatoshi Tsuji
  • Patent number: 7034745
    Abstract: 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.
    Type: Grant
    Filed: March 3, 2004
    Date of Patent: April 25, 2006
    Assignee: Fujitsu Ten Limited
    Inventor: Osamu Isaji
  • Patent number: 7023377
    Abstract: The invention relates to remote distance measurement by means of a transmitted noise modulated probing signal (E), whereby at least one of a distance (Y(t)) and a velocity (V(t)) in relation to a signal transceiver (200) is determined. The probing of signal (E) is generated on basis of at least one first noise signal (x1(t), x2(t)). The transmitted signal (E) is presumed to be reflected to the signal transceiver (200) via at least one signal reflecting object in the form of an information carrying signal (e). This signal thus constitutes a delayed and possibly doppler shifted version of the transmitted signal (E). Moreover, according to the invention, a second noise signal (x2(t)) is added either to the probing signal (E) before it is transmitted or to the information carrying signal (e) before information pertaining to the reflecting object is derived there from.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: April 4, 2006
    Assignee: Saab AB
    Inventor: Sune Axelsson
  • Patent number: 6972710
    Abstract: In an automotive radio wave radar, a center frequency of a transmitted wave is shifted at a certain cycle, and position information of an obstacle detected at three or more center frequencies is subjected to decision by majority to determine whether detection results of the obstacle are erroneous with the occurrence of jamming. If any of the detection results is determined to be abnormal, the abnormal result is discarded. An automotive radio wave radar is realized which can correctly perform the obstacle detection even in the event of jamming without causing erroneous obstacle detection or omission of the detection.
    Type: Grant
    Filed: September 22, 2003
    Date of Patent: December 6, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Shigeaki Matsubara, Kazuaki Takano, Hiroshi Kuroda
  • Patent number: 6956521
    Abstract: A radar device includes a mixer that mixes an output of a transmit antenna 4 and an input of a receive antenna 6, an LPF 8, an A/D converter 9 that samples an output signal of the LPF 8 and subjects the sampled signal to A/D conversion, an FFT processing device 10 that subjects the converted signal to high-speed Fourier transformation, an aliasing discriminating/correcting device that discriminates a signal having a frequency component where aliasing occurs from a result by the FFT processing device 10 and corrects the signal to a signal of a normal frequency component where no aliasing occurs to obtain a distance and relative velocity data of the object, and a target object selecting device that selects necessary data from the distance and relative velocity data of the object which are obtained from the aliasing discriminating/correcting means.
    Type: Grant
    Filed: April 8, 2003
    Date of Patent: October 18, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Koichi Kai
  • Patent number: 6933878
    Abstract: A wave-form generator drives a number of microwave generating devices each operating at different frequency bands. The output of each microwave generator is connected to its own transmission channel of limited bandwidth which contains all the non-linear components necessary for transmission such as an amplifier, T/R switch, rotary joint and beam switch. These individual channels are finally combined onto a common wideband channel which contains only substantially linear components such as a single waveguide and the antenna itself. Because of the isolation between channels there is little or no opportunity for the generation of harmonics or intermodulation distortions which would otherwise occur in a transmitter capable of operating over a very wide bandwidth.
    Type: Grant
    Filed: November 20, 1985
    Date of Patent: August 23, 2005
    Assignee: Bae Systems Electronics Limited
    Inventor: Robert Bewes Molyneux-Berry
  • Patent number: 6924762
    Abstract: A radar is provided which transmits a radar wave whose frequency is so modulated as to rise, fall, and be kept constant cyclically. The radar uses beat signals produced by the radar wave and radar echoes received by two antennas to produce radar data on a target. When it is impossible to pair frequency peaks of the beat signals in a modulated frequency-rising and -falling ranges, the radar determines that the frequency peaks have arisen from different objects so that they overlap each other and uses frequency peaks of the beat signals in a constant modulated frequency range to acquire the radar data.
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: August 2, 2005
    Assignee: Denso Corporation
    Inventors: Yasuyuki Miyake, Kazuma Natsume
  • Patent number: 6906661
    Abstract: In an object-detecting system using an FM-CW wave, points f1 to f4 corresponding to detection peaks of a reflected wave from a road-side object such as guardrail and points m1 and m2 corresponding to detection peaks of a reflected wave from a moving object such as a reflector of a preceding vehicle are indicated on two-dimensional coordinates along with the shape of a road ahead of a subject vehicle. Among the points f1 to f4, m1 and m2, the points f1 to f4 are determined as being provided by the reflected wave from the road-side object, and a distance from the subject vehicle to the object and a speed of the subject vehicle relative the object are calculated using the remaining points m1 and m2 excluding the points f1 to f4. Thus, only the moving object except the road-side object can be detected.
    Type: Grant
    Filed: October 10, 2003
    Date of Patent: June 14, 2005
    Assignee: Honda Motor Co., Ltd.
    Inventors: Kiichiro Sawamoto, Hiroyuki Ando
  • Publication number: 20040252047
    Abstract: A radar is provided which transmits a radar wave whose frequency is so modulated as to rise, fall, and be kept constant cyclically. The radar uses beat signals produced by the radar wave and radar echoes received by two antennas to produce radar data on a target. When it is impossible to pair frequency peaks of the beat signals in a modulated frequency-rising and -falling ranges, the radar determines that the frequency peaks have arisen from different objects so that they overlap each other and uses frequency peaks of the beat signals in a constant modulated frequency range to acquire the radar data.
    Type: Application
    Filed: May 13, 2004
    Publication date: December 16, 2004
    Inventors: Yasuyuki Miyake, Kazuma Natsume
  • Publication number: 20040227662
    Abstract: In an object-detecting system using an FM-CW wave, points f1 to f4 corresponding to detection peaks of a reflected wave from a road-side object such as guardrail and points m1 and m2 corresponding to detection peaks of a reflected wave from a moving object such as a reflector of a preceding vehicle are indicated on two-dimensional coordinates along with the shape of a road ahead of a subject vehicle. Among the points f1 to f4, m1 and m2, the points f1 to f4 are determined as being provided by the reflected wave from the road-side object, and a distance from the subject vehicle to the object and a speed of the subject vehicle relative the object are calculated using the remaining points m1 and m2 excluding the points f1 to f4. Thus, only the moving object except the road-side object can be detected.
    Type: Application
    Filed: October 10, 2003
    Publication date: November 18, 2004
    Inventors: Kiichiro Sawamoto, Hiroyuki Ando
  • Publication number: 20040189510
    Abstract: The intrusion detection system comprises a pair of narrow-beam microwave detectors exploiting Doppler effect and independently operating. A processing unit analyses the signals received by both detectors versus time and Doppler frequencies and amplitude. Analysis of such data allows detecting an actual intrusion. The processing unit also analyses the steady presence of the radio-frequency signal at each detector, to ascertain possible failures or tampering of the system.
    Type: Application
    Filed: February 11, 2004
    Publication date: September 30, 2004
    Inventors: Giovanni Negro, Rinaldo Condello
  • Patent number: 6795012
    Abstract: In a radar, a coupler extracts a part of a transmission signal as a local signal and a mixer mixes a reception signal from a circulator and the local signal so as to output an intermediate frequency signal which is the frequency difference between the transmission signal and the reception signal. An IF-amplifying circuit amplifies the intermediate frequency signal and an AD converter converts the signal to digital data. A DC-removing unit removes a DC component by subtracting the average from the data and an FFT operation unit performs fast Fourier transform so that the distance to a target and the relative velocity of the target are calculated based on a peak included in the frequency spectrum.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: September 21, 2004
    Assignee: Murata Manufacturing Co. Ltd.
    Inventors: Motoi Nakanishi, Toru Ishii, Tetsu Nishimura
  • Patent number: 6778129
    Abstract: The crossover detection method of a radar apparatus according to the present invention calculates distance/relative velocity information at a multitude of different clock times, using a beat signal; calculates predicted distance/relative velocity information indicating distance/relative velocity, respectively, of a target after a prescribed time has elapsed; calculates predicted distance/relative velocity errors by subtracting the calculated distance/relative velocity information from the calculated predicted distance/relative velocity information, respectively; calculates degree of similarity information, based on the predetermined average predicted distance/relative velocity errors and the calculated predicted distance/relative velocity errors; and determines whether there is crossover, based on the above information.
    Type: Grant
    Filed: March 31, 2003
    Date of Patent: August 17, 2004
    Assignee: Fujitsu Limited
    Inventors: Satoshi Ishii, Yoshikazu Dooi, Masayuki Kishida
  • Publication number: 20040150550
    Abstract: An FM-CW radar apparatus capable of detecting a stationary object, in particular, an overbridge, located above the road ahead in a simple manner uses a traveling wave antenna as a transmitting antenna, and includes a means for varying, in upward and downward directions the projection angle of a combined beam pattern of a transmitted wave radiated from the traveling wave antenna, and an overbridge is detected by varying the projection angle of the combined beam pattern in the upward direction using the varying means. Further, a phase shifter for varying the projection angle of the beam pattern in upward/downward directions by controlling the phase of the radio wave to be transmitted or received is provided on either a transmitting antenna or a receiving antenna or on a transmitting/receiving antenna, and an overbridge is detected by controlling the phase shifter and varying the projection angle of the beam pattern in the upward direction.
    Type: Application
    Filed: January 20, 2004
    Publication date: August 5, 2004
    Inventors: Masayoshi Shouno, Masaki Hitotsuya
  • Publication number: 20040150552
    Abstract: A method for processing pulsed-Doppler radar signals to detect a target includes transmitting radar signals from a radar system according to a predetermined frequency technique including signals having frequency diversity, receiving signals within a frequency band, including a target return signal having a frequency indicative of the velocity of the target, and transforming the target return signal using a Fourier Transform having a variable frequency scale.
    Type: Application
    Filed: January 30, 2003
    Publication date: August 5, 2004
    Inventors: Peter F. Barbella, Tamara L. Franz, Barbara E. Pauplis
  • Publication number: 20040140927
    Abstract: In a method for determination of the length of objects in traffic, especially passenger cars, trucks, buses, motorbikes, bicycles and pedestrians, radar signals are transmitted by a vehicle, the radar signals are reflected by an object being measured, the reflected radar signals are received in the vehicle, the frequency spectra of the reflected radar signals are evaluated, and the reflection peaks contained in the frequency spectra are determined. Length measurement, by means of known radar sensors, from a vehicle is made possible by the fact that the width of the reflection peaks is determined, and that the length of the object being measured is determined by means of the determined width.
    Type: Application
    Filed: December 12, 2003
    Publication date: July 22, 2004
    Inventors: Marc-Michael Meinecke, Ralph Mende, Marc Behrens
  • Publication number: 20040125011
    Abstract: Provided is a radar apparatus capable of continuously and stably making a detection of a target even if a reflected wave from a target already detected falls into obscurity due to the presence of low-frequency noises or reflected waves from other targets. An estimated value of information on a target to be obtained when the target is detected in the present cycle are acquired from the target detected in a previous cycle. When a peak compatible with the estimated value is detected in only one of a frequency-rising section and a frequency falling section of a radar wave, if the frequency of the non-detected peak pertains a low-frequency noise domain or if a side-by-side travel flag is set with respect to the target detected in the previous cycle, the non-detected peak is considered as buried by low-frequency noises or peaks of other targets, and a peak pair corresponding to the detected target is extrapolated.
    Type: Application
    Filed: December 18, 2003
    Publication date: July 1, 2004
    Applicant: DENSO CORPORATION
    Inventors: Hiroaki Kumon, Yukimasa Tamatsu
  • Patent number: 6756933
    Abstract: A radar system and a characteristic adjustment method for the radar system are provided, in which a control voltage waveform of a voltage controlled oscillator for frequency-modulating a sending signal can be set in a short time without increasing the required amount of memory. In adjusting time-varying characteristics of a voltage signal for frequency modulation on a voltage controlled oscillator determining a sending frequency, the time-varying characteristics of the voltage signal for frequency modulation are adjusted to optimize a form of a protrusion in signal intensity included in a frequency spectrum of a beat signal.
    Type: Grant
    Filed: November 21, 2002
    Date of Patent: June 29, 2004
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Toru Ishii, Motoi Nakanishi, Tetsu Nishimura
  • Publication number: 20040108952
    Abstract: A signal from CW radar is received, and the received power detected by the CW radar's swinging in all directions is averaged in each direction. Then, the maximum value and the minimum value of the received power are detected for each direction, and the difference between the maximum value and the minimum value is computed. An average power value of obtained power is also computed. On a 2-dimensional plane on which the difference between the maximum value and the minimum value and the average power value are used for coordinate axes, slice processing is performed using a threshold indicated by a line graph or a curve.
    Type: Application
    Filed: November 20, 2003
    Publication date: June 10, 2004
    Applicant: FUJITSU LIMITED
    Inventors: Satoshi Ishii, Yoshikazu Dooi, Sadanori Matsui
  • Publication number: 20040066322
    Abstract: An in-vehicle pulse radar device includes: an oscillator that generates an electromagnetic wave; a transmission amplifier that transmits the electromagnetic wave generated by the oscillator toward a target substance; an antenna that receives the reception electromagnetic wave reflected by the target substance to output data; reception amplifiers; a reception antenna; an A/D converter; and a signal processing device that pre-sums data which is sampled on the basis of the data from the A/D converter for each of distance gates, subjects the pre-summed data which is a result of the pre-summing process to an FFT process, and obtains a distance between a subject vehicle and the target substance and a relative speed therebetween in accordance with the spectrum frequency and the amplitude information which are a result of the FFT process.
    Type: Application
    Filed: May 8, 2003
    Publication date: April 8, 2004
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventor: Naohisa Uehara
  • Publication number: 20040066331
    Abstract: The invention concerns a passive radar receiver for a received orthogonal frequency division multiplex-type signal consisting of symbol frames each emitted on coded orthogonal carriers. After formatting the received signals into digital symbols (S1 S1), a filtering circuit (2) eliminates by subtraction or using a covariance matrix, in the symbol signal at least unwanted signals with null Doppler effect so as to apply a filtered signal (X′) including essentially signals backscattered by mobile targets to a Doppler-distance correlator (4).
    Type: Application
    Filed: July 30, 2003
    Publication date: April 8, 2004
    Inventor: Dominique Poullin
  • Publication number: 20040051660
    Abstract: A radar device includes a mixer that mixes an output of a transmit antenna 4 and an input of a receive antenna 6, an LPF 8, an A/D converter 9 that samples an output signal of the LPF 8 and subjects the sampled signal to A/D conversion, an FFT processing device 10 that subjects the converted signal to high-speed Fourier transformation, an aliasing discriminating/correcting device that discriminates a signal having a frequency component where aliasing occurs from a result by the FFT processing device 10 and corrects the signal to a signal of a normal frequency component where no aliasing occurs to obtain a distance and relative velocity data of the object, and a target object selecting device that selects necessary data from the distance and relative velocity data of the object which are obtained from the aliasing discriminating/correcting means.
    Type: Application
    Filed: April 8, 2003
    Publication date: March 18, 2004
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventor: Koichi Kai
  • Patent number: 6703967
    Abstract: From a transmitter (18) and a transmission antenna (10), a first frequency signal having a fixed frequency is transmitted for a predetermined time or more, a second frequency signal having a certain frequency difference from the first frequency signal is transmitted for a predetermined time or more, and a third frequency signal having a frequency difference twice the frequency distance from the first frequency signal is transmitted for a predetermined time or more. Reflected waves from objects under measurement at the respective transmission frequencies are supplied to a reception antenna (11), a mixer (12), an analog circuit unit (13), an A/D converter (14), an FFT (15) and a signal processing unit (16).
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: March 9, 2004
    Assignee: Hitachi Ltd.
    Inventors: Hiroshi Kuroda, Kazuaki Takano, Mitsuru Nakamura
  • Patent number: 6703966
    Abstract: To measure the absolute speed of a body 100 moving relative to the ground 33 using an onboard speed sensor 1, a radar wave is transmitted towards the ground by an antenna with a wide aperture angle. The wave reflected by a reflecting obstacle on the ground and the transmitted wave are mixed and the frequency content of the low frequency signal obtained is determined. The speed of the moving object and the height of the transmitter and receiver antennas above the ground can then be measured by adjusting a theoretical curve to the time-varying evolution of the Doppler frequency corresponding to the reflecting obstacle.
    Type: Grant
    Filed: August 2, 2002
    Date of Patent: March 9, 2004
    Inventors: Céline Corbrion, Jacques Lewiner, Thierry Ditchi, Eric Carreel
  • Publication number: 20040041727
    Abstract: The crossover detection method of a radar apparatus according to the present invention calculates distance/relative velocity information at a multitude of different clock times, using a beat signal; calculates predicted distance/relative velocity information indicating distance/relative velocity, respectively, of a target after a prescribed time has elapsed; calculates predicted distance/relative velocity errors by subtracting the calculated distance/relative velocity information from the calculated predicted distance/relative velocity information, respectively; calculates degree of similarity information, based on the predetermined average predicted distance/relative velocity errors and the calculated predicted distance/relative velocity errors; and determines whether there is crossover, based on the above information.
    Type: Application
    Filed: March 31, 2003
    Publication date: March 4, 2004
    Applicants: FUJITSU LIMITED, FUJITSU TEN LIMITED
    Inventors: Satoshi Ishii, Yoshikazu Dooi, Masayuki Kishida