347 results about "Radar beam" patented technology

An example radar system for a vehicle comprises a radar antenna, operable to produce a radar beam, and a lens assembly including at least one active lens, the radar beam passing through the lens assembly. The radar beam has a field of view that is adjustable using the active lens. In some examples, the active lens comprises a metamaterial, the metamaterial having an adjustable property such as an adjustable negative index, the field of view being adjustable using the adjustable property of the metamaterial.

An airborne radar system is disclosed. The airborne radar system comprises a radar antenna, radar circuitry coupled to the radar antenna, and a runway database comprising runway location information. The airborne radar system also comprises a processing device retrieving from the runway database, runway location information for a runway being approached by an aircraft, based on the location of the aircraft, and directing a radar beam defined by a polygon which represents the runway and which is derived from the runway information, the processing device determining whether there are any obstacles on the runway.

A CW radar (10) is used to detect motion of objects (22) behind a wall (20) by projecting a radar beam through the wall and by measuring the returns from the objects behind the wall, with a change in the phase difference between the transmitted and received CW signals providing an indication of motion behind the wall and thus the presence of an individual.

An improved system is provided for aiming a shotgun-based or other countermeasure system so as to be able to countermeasure incoming rockets or projectiles. In one embodiment a shotgun aimed and controlled by the subject system projects a pattern of pellets to intercept a rocket-propelled grenade or incoming projectile. The fire control system uses a CW two-tone monopulse radar to derive range and angle of arrival within 150 milliseconds, with range and angle of arrival measurements having approximately twice the accuracy of prior CW two-tone monopulse radars. The improvement derives from using all of the information in the returned radar beams and is the result of the recognition that one can use the Sum and Difference signals to assemble a two-by-two Rank One matrix that permits using singular value decomposition techniques to generate range and angle of arrival matrices in which all available information is used and in which noise is eliminated.

A radar microchip for short range detection with phased array radar uses phase shifters along with an antenna array to steer the transmitted and received radar beams along orthogonal axes to achieve a 3D scan. Individual phase shifters connected to antenna cells that transmit and receive the radar beams steer the radar along two orthogonal axes by controlling the phase of the radar. The radar then detects where the two beams overlap. The antenna cells are further aligned along these orthogonal axes. An isolation barrier between the phase shifters of the transmitted and received signals reduces cross coupling on the radar microchip.

A radar detection process includes computing a derivative of an FFT output signal to detect an object within a specified detection zone. In one embodiment, a zero crossing in the second derivative of the FFT output signal indicates the presence of an object. The range of the object is determined as a function of the frequency at which the zero crossing occurs. Also described is a detection table containing indicators of the presence or absence of an object within a respective radar beam and processing cycle. At least two such indicators are combined in order to detect the presence of an object within the detection zone.

The invention relates to a method for detecting the passage by a vehicle of a determined point for monitoring on a road, wherein from a remotely situated location a radar beam is transmitted continuously to the point for monitoring, reflections from the transmitted radar beam are received at the remotely situated location, and it is determined from the received reflections that the vehicle is passing the point for monitoring. The radar beam can herein be transmitted at an acute angle to the travel direction of the passing vehicle. The detection can be used to activate a red-light camera, to measure the speed of the vehicle or measure the traffic intensity, without sensors, for instance induction loops, having to be arranged in the road for this purpose. The invention further relates to a system for performing this method.

In the on-vehicle radar apparatus of the present invention, the vertical scanning width of the radar beam is narrowed, before the horizontal scanning, thereby avoiding unnecessary data processing and improving the data processing efficiently. Further, the SIN ratio of the target detection signal is increased, thereby stabilizing the distance detection and its accuracy. The vertical scanning antenna is a single travelling wave excitation antenna (TWEA) constructed by a plurality of antenna elements. At the same time, the horizontal scanning antenna is a multi-channel antenna wherein a plurality of TWEAs is assigned to a plurality of horizontal directions. The horizontal scanning angle is arbitrarily widened by increasing the number of TWEAs.

A heating element for an inside surface of a front-end module / bumper for a motor vehicle. The heating element is operatively connected to a radar transmitting / receiving unit. The heating element comprises a heating film formed of a polymer, an array of conductor strips integrated into the heating film, and an electronic control element that controls the conductor strips. The array of conductor strips is divided into an inner region through which a radar beam from the radar transmitting / receiving unit is transmitted, and an outer region through which the radar beam is not transmitted. The conductor strips in the inner region are inclined by angles of about 45° to about 90° relative to a polarization plane of the radar beam. The conductor strips in the outer region are arranged in a meandering pattern.

The invention relates to a method and device with which a vehicle traveling through a radar cone is classified by means of length criteria. The length criteria are formed by the difference of the driven distance that the vehicle covers, during which it reflects the radar beam, and the passage distance of the vehicle through the radar cone, which gives a more or less precise measurement for the vehicle length according to the accuracy of the determined passage distance. For determining the passage distance, range values are derived from the radar signals.

A radome for a radar sensor that includes a first and second section. Each section is formed of layers that have an electrical thickness substantially equal to an integer multiple of a guided half-wavelengths of the radar beam. Each of the sections are configured such that, at a location spaced apart from the radome, a first phase angle of the first portion of the radar beam differs from a second phase angle of the second portion of the radar beam by an amount substantially corresponding to an integer number of three hundred sixty degrees (360°) of phase angle shift.

The invention discloses a microwave over-the-horizon radar echo chart calculating method, which comprises the following steps: 1) determination of relevant parameters, target parameters and environment parameters of a microwave over-the-horizon radar; 2) prediction of characteristic parameters of an evaporation waveguide and measurement of characteristic parameters of a surface waveguide; 3) calculation of an atmosphere waveguide or atmosphere refraction propagation sea surface glancing angle; 4) calculation of an atmosphere waveguide or atmosphere refraction propagation factor; 5) calculation of a sea clutter and target echo power diagram; and 6) simulation of a dynamic radar echo chart. The disclosed microwave over-the-horizon radar echo chart calculating method takes influence, formed under ocean hydrological conditions, of atmospheric duct propagation on sea surface echoes and target echoes into full consideration under the actual microwave over-the-horizon radar working environment, provides an actual radar beam sea surface grazing angle calculating method under the atmospheric refraction or atmospheric duct condition on the basis of radar system parameters and marine hydrometeorological parameters, and with relevant sea clutter models being combined, can effectively predicate and estimate the sea surface echo power.

An imaging apparatus has transmitter illuminating a selected surface with a radar beam footprint, and processor for profiling / processing the radar returns so as to derive attitude information in real time about a number of predefined axes associated with the radar which depends upon the relative dispositions of the radar, the selected surface and upon the radar beam footprint characteristics.A plurality of transmit beams image the surface and the processing arrangement has the capability of determining roll, pitch and / or yaw pointing data associated with the radar, such pointing data being determined by derivation of the attitude information and by selective input of terrain elevation data so as to take account of variations in the radar viewing geometry with terrain elevation.This provides a low cost advantage over known radar designs, and retains utility for many applications, for example spaceborne and airborne applications.

The invention belongs to the technical field of frequency distribution array (FDA) radars and discloses a method for utilizing a frequency distribution array (FDA) radar to estimate an object distance and an azimuthal angle. The method comprises the steps of dividing transmitting array elements of the radar into a first transmitting subarray and a second transmitting subarray with equal array element numbers, generating transmitting signals of the two transmitting subarrays, and estimating the azimuthal angle of the distance of an object. According to the method, the distance dependence characteristics of FDA radar beam can be effectively utilized to perform joint estimation on the azimuthal angle of the distance of the object, and the coupled problem which occurs when the FDA radar is utilized to estimate the distance and the azimuthal angle of the object is solved.

An improved system is provided for aiming a shotgun-based or other countermeasure system so as to be able to countermeasure incoming rockets or projectiles. In one embodiment a shotgun aimed and controlled by the subject system projects a pattern of pellets to intercept a rocket-propelled grenade or incoming projectile. The fire control system uses a CW two-tone monopulse radar to derive range and angle of arrival within 150 milliseconds, with range and angle of arrival measurements having approximately twice the accuracy of prior CW two-tone monopulse radars. The improvement derives from using all of the information in the returned radar beams and is the result of the recognition that one can use the Sum and Difference signals to assemble a two-by-two Rank One matrix that permits using singular value decomposition techniques to generate range and angle of arrival matrices in which all available information is used and in which noise is eliminated.

A road surface detection apparatus capable of detecting an upward / downward displacement in radar axis when detecting a road surface by projecting a radar beam. The apparatus projects a radar beam signal onto the road surface on which the radar-equipped vehicle is traveling, and receives a signal containing a reflected signal of the radar beam signal. Then, the apparatus compares the level of the road surface reflected signal contained in the received signal with a predetermined reference level and, if the result of the comparison lies outside a predefined range, then the apparatus determines that the axis defining the projection direction of the radar beam signal is displaced.

A radar detection process includes computing a derivative of an FFT output signal to detect an object within a specified detection zone. In one embodiment, a zero crossing in the second derivative of the FFT output signal indicates the presence of an object. The range of the object is determined as a function of the frequency at which the zero crossing occurs. Also described is a detection table containing indicators of the presence or absence of an object within a respective radar beam and processing cycle. At least two such indicators are combined in order to detect the presence of an object within the detection zone and with changing range gates in each of the antenna beams the coverage of the detection zone can be varied.

A method and apparatus for electronically steering a RADAR beam across an array of feed horns by moving the phase center of the beam to different origination points on the array—each origination point being the phase center of a feed horn pair. Variations include polarized beams, polarized feed horns, dual-beam systems, dual direction steering, diagonal steering, and cross-polarized wire grids to control beamwidth.

An imaging apparatus 6 has means for illuminating a selected surface with a radar beam footprint, and means for profiling / processing the resultant radar returns in an efficient and logical fashion such as to derive radar attitude information in real time about a number of predefined axes associated with the radar which depends upon the relative dispositions of the radar and the selected surface and upon the radar beam footprint characteristics. Advantageously, a plurality of transmit beams 10,11,12 are used to image the surface and the processing arrangement has the capability of determining roll, pitch and / or yaw pointing data associated with the radar, such pointing data being determined by derivation of the attitude information and by selective input of terrain elevation data so as to take account of variations in the radar viewing geometry with terrain elevation. The inventive radar bears a definite low cost advantage over known radar designs, and retains utility for many applications, for example spaceborne and airborne applications.

The process is used for suppressing the effect of signals that are received or sent via side lobes of an antenna (PA; HA) of an amplitude or phase monopulse radar device, in which for the purpose of position measurement of a first and, if need be, a second target (T1, T2) detected by the radar beam, three illumination functions Je(Lx), Jk(Lx) and Js(Lx) for the antenna (PA; HA) are provided for each measurement axis, as well as antenna functions Fe(X), Fk(X), and Fs(X) resulting from them. The first, second, and third illumination functions Je(Lx); Jk(Lx), and Js(Lx) are selected in this connection so that a quotient function Qe(X)=Fe(X) / Fs(X) or Qk(X)=Fk(X) / Fs(X), which is linearly or quadratically dependent on the target direction, is produced by normalizing the first and the second antenna functions Fe(X); Fk(X) with the third antenna function Fs(X). The power of this quotient is compared with at least one threshold value the or thk that is selected in accordance with the magnitude of the main antenna lobe, and when the threshold value the or thk is exceeded, the effect of the received signal is suppressed. In a preferred embodiment of the invention, the provision is made that the zero points of the antenna functions Fe(X), Fk(X), and Fs(X) are shifted slightly in relation to one another.

One embodiment of the present invention relates to a radar transmitter comprised within a single integrated chip substrate, which is capable of continuous beam steering of a transmitted radar beam as well as an option to change the physical position of the origin of the transmit radar beam. The radar transmitter has a signal generator that generates an RF signal. The RF signal is provided to a plurality of independent transmission chains, which contain independently operated vector modulators configured to introduce an individual phase adjustment to the high frequency input signal to generate separate RF output signals. A control unit is configured to selectively activate a subset of (e.g., two or more) the independent transmission chains. By activating the subset of independent transmission chains to generate RF output signals with separate phases, a beam steering functionality is enabled. Furthermore, the subset defines a changeable position of the transmitted radar beam.

A reflected energy detecting device includes a transmitter for transmitting an electromagnetic signal and a receiver for receiving a reflected electromagnetic signal. An antenna may be operatively connected with the transmitter and the receiver for radiating the electromagnetic signal and capturing the reflected electromagnetic signal and the antenna may be movable. A main controller may be provided for controlling operation of the transmitter and the receiver and the movement of the antenna and the reflected energy detecting device may further include at least one platform. The at least one platform may support a remote reflector that is dimensioned and configured to redirect the transmitted electromagnetic signal in a desired direction and a platform controller that is configured to communicate with the main controller and to maintain alignment between the remote reflector and the antenna.

A method for detecting and documenting red-light violations and / or speeding violations in which a radar beam is directed across all lanes of a roadway of interest and in which the speed and the position of a vehicle which passes through the radar beam are determined from the radar signals so as to be able to predict the probability of a red-light violation from the speed and the determined distance of the measured vehicle from a stop line and to trigger the recording of images of the violating vehicle at predetermined distances from the stop line.

An apparatus is disclosed for measuring the position of a vehicle or a surface thereof on a roadway. The apparatus comprises at least one radar transmitter, which is arranged in a transmitting position above the plane of the roadway and transmits radar beams downwardly, a plurality of radar receivers, which are distributed above the plane of the roadway in different receiving positions at distances from one another, receive reflections of the radar beams from beneath, and convert the reflections into a received signal, and an evaluation device, which is connected to the radar transmitter and the radar receivers and is configured to measure the said position from the transmitting position, the receiving positions and the received signals.

A SAR imaging method performs N SAR acquisitions in stripmap mode of the earth's surface using a synthetic aperture radar transported by an aerial or satellite platform and including a single, non-partitioned antenna and a single receiver coupled thereto. All N SAR acquisitions are performed using the same predetermined elevation angle relative to the nadir of the synthetic aperture radar and using a respective squint angle relative to the flight direction of the synthetic aperture radar. Radar transmission and reception operations are time interleaved with other N-1 SAR acquisitions, resulting in the respective acquisition directions being parallel to each other and not parallel to acquisition directions of other N-1 SAR acquisitions. Radar beams in two immediately successive time instants and related to two different SAR acquisitions are contiguous along the azimuth. SAR images may be generated using all the N SAR acquisitions having an enhanced azimuth resolution.

A sensor assembly that integrates a camera and a radar sensor is described herein. The sensor assembly includes a housing configured to partially enclose the camera and the radar sensor, and define a partial radome that partially intrudes into the radar beam. The partial radome is configured such that after passing through the partial radome a first phase angle of the first portion of the radar beam differs from a second phase angle of the second portion of the radar beam by an amount substantially corresponding to an integer number of three hundred sixty degrees (360°) of phase angle shift. The partial radome provides glare shield to the camera, protection to assembly, and is configured to minimally effect radar performance.

The invention discloses a fast Realization method for simulation 3D scene SAR radar echo based on forward method. The main idea of the fast Realization method comprises the following steps: acquiring digital elevation model (DEM) data within SAR radar beam range, wherein the data comprises K point targets; randomly distributing the K point targets on a 2D ground in the geographic coordinate system, and calculating DEM data within the SAR radar beam range after refinement processing; acquiring back scattering property distribution of the DEM data within the SAR radar beam range after refinement processing; utilizing an improved downward angle comparison method to determine shaded areas of Q small surface elements, calculating final actual back scattering coefficients of the Q small surface elements after shaded area determination, and then calculating SAR radar echo of the Q small surface elements. At this time, the whole 3D scene echo simulation is completed in a graphic processing unit (GPU), and finally an echo signal in the GPU is sent to a CPU processor to be output.

The invention provides a method for eliminating terrestrial clutters of an airborne weather radar based on terrain altitude data. The method provided by the invention comprises the following steps of: reading airplane position and radar parameters, establishing a local rectangular coordinate system, calculating longitudes and latitudes of ground sampling points in a beam direction, reading DEM (Digital Elevation Model) data, calculating a lower view angle sequence of the sampling points relative to an airplane, analyzing a tendency of the lower view angle sequence, judging a monotonically decreasing sequence, eliminating a non-monotonically-decreasing lower view angle value, determining a beam grounding range, editing echo signals and replacing by a background, updating the airplane position and an antenna azimuth angle, judging whether the scanning is finished, displaying complete scanning echo signals by a radar display screen and the like. According to the method provided by the invention, by utilizing the characteristics that the terrestrial clutters of the airborne weather radar echoes and weather targets are respectively located at units with different distances and can be separated in the distance and adopting the discipline characteristics of the lower view angle, the grounding position of the radar beam is analyzed, and the terrestrial clutters is eliminated by utilizing and utilizes the terrain altitude data; and the method has the advantages of simple method, calculation accuracy, good inhibition effect, capability of effectively eliminating terrestrial cluttersof the airborne weather radar in a time domain and the like.