873 results about "Radar imaging" patented technology

A Catheter Guidance Control and Imaging (CGCI) system whereby a magnetic tip attached to a surgical tool is detected, displayed and influenced positionally so as to allow diagnostic and therapeutic procedures to be performed is described. The tools that can be so equipped include catheters, guidewires, and secondary tools such as lasers and balloons. The magnetic tip performs two functions. First, it allows the position and orientation of the tip to be determined by using a radar system such as, for example, a radar range finder or radar imaging system. Incorporating the radar system allows the CGCI apparatus to detect accurately the position, orientation and rotation of the surgical tool embedded in a patient during surgery. In one embodiment, the image generated by the radar is displayed with the operating room imagery equipment such as, for example, X-ray, Fluoroscopy, Ultrasound, MRI, CAT-Scan, PET-Scan, etc. In one embodiment, the image is synchronized with the aid of fiduciary markers located by a 6-Degrees of Freedom (6-DOF) sensor. The CGCI apparatus combined with the radar and the 6-DOF sensor allows the tool tip to be pulled, pushed, turned, and forcefully held in the desired position by applying an appropriate magnetic field external to the patient's body. A virtual representation of the magnetic tip serves as an operator control. This control possesses a one-to-one positional relationship with the magnetic tip inside the patient's body. Additionally, this control provides tactile feedback to the operator's hands in the appropriate axis or axes if the magnetic tip encounters an obstacle. The output of this control combined with the magnetic tip position and orientation feedback allows a servo system to control the external magnetic field.

Methods and apparatus are presented which reduce the overall cost and increase the imaging capability for medium and long range automotive radar sensing applications through the combination of a high signal-to-noise ratio and wide dynamic range radar waveform and architecture, antenna arrangement, and a low cost packaging and interconnection method. In accordance with aspects of the present invention, one way a high signal-to-noise ratio and wide dynamic range imaging radar with reduced cost can be achieved is through the combination of a pulsed stepped-frequency-continuous-wave waveform and electrically beam-switched radar architecture, utilizing a planar package containing high-frequency integrated circuits as well as integrated high-frequency waveguide coupling ports, coupled to a multi-beam waveguide-fed twist-reflector narrow beam-width antenna. Other methods and apparatus are presented.

Method and apparatus for developing radar scene and target profiles based on Compressive Sensing concept. An outgoing radar waveform is transmitted in the direction of a radar target and the radar reflectivity profile is recovered from the received radar wave sequence using a compressible or sparse representation of the radar reflectivity profile in combination with knowledge of the outgoing wave form. In an exemplary embodiment the outgoing waveform is a pseudo noise sequence or a linear FM waveform.

A 3D imaging ladar system comprises a solid state laser and geiger-mode avalanche photodiodes utilizing a scanning imaging system in conjunction with a user interface to provide 3D spatial object information for vision augmentation for the blind. Depth and located object information is presented acoustically by: 1) generating an audio acoustic field to present depth as amplitude and the audio image as a 2D location. 2) holographic acoustical imaging for a 3D sweep of the acoustic field. 3) a 2D acoustic sweep combined with acoustic frequency information to create a 3D presentation.

A system to fuse data derived from a three dimensional imaging ladar system with information from a visible, ultraviolet, or infrared camera systems and acoustically present the information in a four or five dimensional acoustical format utilizing three dimensional acoustic position information, along with frequency, and modulation to represent color, texture, or object recognition information is also provided.

A method of radar-imaging a scene in the far-field of a one-dimensional radar array, comprises providing an array of backscatter data D(f_m, x′n) of the scene, these backscatter data being associated to a plurality of positions x′_n, n=0 . . . N−1, N>1, that are regularly spaced along an axis of the radar array. The backscatter data for each radar array position x′n are sampled in frequency domain, at different frequencies f_m, m=0 . . . M−1, M>1, defined by f_m=f_c−B/2+m−Δf, where f_c represents the center frequency, B the bandwidth and Δf the frequency step of the sampling. A radar reflectivity image 1(α_m′, β_n′) is computed in a pseudo-polar coordinate system based upon the formula (2) with formula (3) where j represents the imaginary unit, formula (A) is the baseband frequency, FFT2D denotes the 2D Fast Fourier Transform operator, α_m′, m′=0 . . . M−1, and β_n′, n′=0 . . . N−1 represent a regular grid in the pseudo-polar coordinate system, and P_max is chosen >0 depending on a predefined accuracy to be achieved. A corresponding method of radar-imaging a scene in the far-field of a two-dimensional radar array is also proposed.

A system for identifying an individual, including an imaging radar for receiving radar data pertaining to at least a portion of a skeleton of at least one individual, an imaging module for generating at least one skeletal image of the at least one individual based on the radar data, at least one database including a plurality of skeletal data pertaining to a plurality of individuals, an identification module for comparing the at least one skeletal image with the plurality of skeletal data to determine a match.

A short range millimeter wave surface imaging radar system. The system includes electronics adapted to produce millimeter wave radiation scanned over a frequency range of a few gigahertz. The scanned millimeter wave radiation is broadcast through a frequency scanned transmit antenna to produce a narrow transmit beam in a first scanned direction (such as the vertical direction) corresponding to the scanned millimeter wave frequencies. The transmit antenna is scanned to transmit beam in a second direction perpendicular to the first scanned direction (such as the horizontal or the azimuthal direction) so as to define a two-dimensional field of view. Reflected millimeter wave radiation is collected in a receive frequency scanned antenna co-located (or approximately co-located) with the transmit antenna and adapted to produce a narrow receive beam approximately co-directed in the same directions as the transmitted beam in approximately the same field of view. Computer processor equipment compares the intensity of the receive millimeter radar signals for a pre-determined set of ranges and known directions of the transmit and receive beams as a function of time to produce a radar image of at least a desired portion of the field of view. In preferred embodiment the invention is mounted on a truck and adapted as a FOD finder system to detect and locate FOD on airport surfaces.

A tissue-sensing adaptive radar method of detecting tumours in breast tissue uses microwave backscattering to detect tumours which have different electrical properties than healthy breast tissue. The method includes steps for reducing skin reflections and for constructing a three-dimensional image using synthetic focusing which shows the presence or absence of microwave reflecting tissues.

The invention provides a laser imaging radar device and a distance measurement method thereof. The laser imaging radar device and the distance measurement method thereof aims at the problem that an existing distance range gate laser imaging radar is low in distance resolution. The laser imaging radar device comprises a laser device, a laser modulation unit, an optical antenna unit, a detecting unit, a data processing unit and an image processing unit, wherein the detecting unit is composed of a counter, a gate controller and an array detector, and the data processing unit is composed of an accumulator and a correlator. According to the distance measurement method, an information loading process is carried out on laser signals with constant amplitude by using a phase code pulse amplitude modulation mode. The laser imaging radar device and the distance measurement method thereof have the advantages that the equipment and the method combine the advantages of long detecting distances of the distance ranging gate layer imaging radar and the advantage of high distance measurement resolution of the pulse phase coding mode, and meanwhile the detect of low distance measurement resolution of the distance ranging gate layer imaging radar and the detect of low imaging speed of the pulse phase coding mode are avoided.

A time-reversal imaging radar system for acquiring an image of a remote target includes an antenna array having a plurality of spaced-apart antennas, and a transceiver coupled to the antenna array for alternately transmitting a radar signal via the antenna array toward the target and for receiving target-reflected radar signals. The transceiver includes means for multiple-pass time-reversing the transmitted and received radar signals whereby coherent beam focusing is realized at both the target and at the receiver to thereby enhance the resolution of the acquired target image.

A radar imaging system for capturing an image of an object within an area of interest through at least one visual impairment. The radar imaging system comprises at least one radar array. The radar array includes a plurality of transmitter elements and a plurality of receiver elements for receiving a plurality of coded return signals from an object through the at least one visual impairment. The system further comprises at least one processor coupled to the transmitter and receiver elements, which is adapted to transmit a plurality of differently coded signals toward the object and the at least one visual impairment; decode the plurality of coded return signals received by each of the receiver elements; extract from the decoded return signals a multiplicity of captured signals for each transmitter to receiver path; focus the multiplicity of signals on all points of interest within the area of interest by aligning the multiplicity of captured signals to be co-incident from a particular point within the area of interest; and sum the aligned signals to produce an image of the object. A method for capturing an image of an object in an area of interest through at least one visual impairment is also provided.

An earth penetrating apparatus includes a cutting tool and a sensor housing. A radar unit, rate sensor unit, processor, and transmitter are provided in the sensor housing. An antenna arrangement is coupled to the radar unit and configured for transmitting and receiving electromagnetic signals in a relatively forward and/or lateral looking direction relative to a distal end of the cutting tool. The rate sensor unit may include one or both of a gyroscope and an accelerometer. The processor receives radar data from the radar unit indicative of subsurface strata and obstacles respectively located generally forward and/or lateral of the cutting tool, and receives displacement data from the rate sensor unit indicative of one or both of longitudinal and rotational displacement of the cutting tool. The transmitter is configured for transmitting one or both of the radar data and the displacement data to an aboveground location.

A three-dimensional imaging radar operating at high frequency e.g., 670 GHz, is disclosed. The active target illumination inherent in radar solves the problem of low signal power and narrow-band detection by using submillimeter heterodyne mixer receivers. A submillimeter imaging radar may use low phase-noise synthesizers and a fast chirper to generate a frequency-modulated continuous-wave (FMCW) waveform. Three-dimensional images are generated through range information derived for each pixel scanned over a target. A peak finding algorithm may be used in processing for each pixel to differentiate material layers of the target. Improved focusing is achieved through a compensation signal sampled from a point source calibration target and applied to received signals from active targets prior to FFT-based range compression to extract and display high-resolution target images. Such an imaging radar has particular application in detecting concealed weapons or contraband.

The invention discloses a scanning three-dimensional imaging laser radar based on a linear array APD detector and an imaging method. The laser radar shapes the circular Gaussian laser beams into stripe laser to be transmitted, the linear array APD detector receives the laser echo, and the receiving field of view of the linear array APD detector coincides with the far-field facula of the laser. The range data are finally obtained after the signals output by the detector are amplified and processed. The laser radar completes measurement of the whole field of view via a two-dimensional scanning mechanism. The invention greatly improves the detection efficiency without increasing the repetition frequency of the laser and can meet the application requirement for demanding imaging time.

The present invention provides a wideband signal synthesizing method based on multi transmitting and multi receiving frequency-division radar, which comprises the following steps: 1) synchronously transmitting M subband signals from M transmitting array elements of transmitting array at the transmitting side of multi transmitting and multi receiving radar; 2) receiving echo signal by N receiving array elements in the receiving array at the receiving end of multi transmitting and multi receiving radar, and obtaining N*M path of receiving signals corresponding to different frequency bands and different array elements as each receiving array element is set with M receiving channels; and 3) executing beam forming processing and matched filtering processing, obtaining M narrow-band signals, adding the frequency spectrum of M narrow-band signals for obtaining the synthesized wideband signal, wherein the final wideband signal is obtained through multiplexing the wideband signal with the reciprocal frequency spectrum window. The invention effectively overcomes the problem that side-lobe generates when a plurality of narrow bands synthesize a broadband signal. Therefore a plurality of narrow-band receiving and transmitting channels can be used for realizing high-resolution distance image according to the invention thereby greatly reducing the requirement of imaging radar to the capability of broadband device.

An imaging processing system and method. In accordance with the invention, the illustrative method includes the steps of providing a transfer function between scene excitations and voltage returns based on geometry, beam pattern and/or scan rate; ascertaining a set of scene excitations that minimize a penalty function of the transfer function; and ascertaining a set of scene intensities based on the scene excitations, and a set of optimal weights for the penalty function based on the scene reflectivities. The inventive method provides significantly enhanced image sharpening. In the illustrative embodiment, the inventive method uses an iterative convergence technique which minimizes a penalty function of the sum of square errors between the scene excitations corrupted by the radar system (i.e. the antenna pattern and processing) and the radar voltage returns. The innovation significantly enhances radar imagery by iteratively deriving a best scene solution, which reduces corruption introduced by the radar system. The novel technique for enhanced discrimination by the radar imagery is an iterative technique, which models the true scene signal corruption and derives a solution for the scene intensities, which minimizes the errors in the derived image. The novel technique finds the scene scatterer powers, which best match the original image pixel powers. The effect of the antenna pattern is taken into consideration when computing the derived image, which is matched against the original image. The constraint is implemented iteratively by adding a weighted sum of scene powers to the penalty function. The weights are adjusted at each iteration.

The invention discloses a method for obtaining mining area earth surface three-dimensional deformation fields through a single interferometric synthetic aperture radar (InSAR) interference pair. The method includes that a mining field radar sight deformation field is obtained through an InSAR technology, pixels with coherence which is lower than an unwrapping threshold value in the sight deformation field is subjected to spatial interpolation to obtain a spatial continuous deformation field, main effective radius of each pixel is calculated through mining area working face distribution and main effective angles, after mining area horizontal shifting coefficients are obtained, the mining area earth surface horizontal shifting is converted to an expression of a sinking value, an equation set is formed according to the radar imaging principle, the equation set is solved to obtain a solution of the earth surface sinking value, according to the sinking value, tilting values of east, west, south and north directions are calculated, and the deformation fields of the east, west, south and north directions are calculated according to a proportional relation among the tilting values of the east, west, south and north directions and the horizontal shifting. The method has the advantages that the restrictions that when the three-dimensional deformation field is solved by the aid of the InSAR, the requirements for data are strict, the monitoring cost is high and the like are broken, and the application space of the InSAR technology in the mining area is greatly widened.

The invention provides a treatment method for a surface target of an unmanned ship based on a laser imaging radar.The method based on the unmanned ship of the laser image radar comprises the following steps: S1, generating a three-dimensional cloud point image on the water surface around the unmanned ship by the laser imaging radar, the three-dimensional cloud point image comprises a target cloud point and a non-target cloud point;conducting dimension reduction treatment to the three-dimensional cloud point image, projecting the three-dimensional cloud point image to a two-dimensional XY-grid plane, counting the position information and height information of each grid, S2, cutting the target cloud point and non-target point cloud, S3,clustering the target point cloud obtained after being cut, extracting the position information of each target, forming the target sample set, extracting multi-dimensional eigenvector collected by the target sample; S4, training the target sample set,obtaining the obtained identifying function, and identifying the target point cloud by the identifying function. The treatment method provided in the invention can detect and identify the target of the water surface around the unmanned ship accurately.