Abstract: A three dimensional imaging radar system and method for generating and processing radar information to produce a three dimensional image of objects viewed by the system. The system is designed to create three dimensional images of physical objects at relatively short range, up to a distance of about 1000 feet. The radar system comprises a servo controlled antenna system, wherein the servo system provides azimuth and elevation pointing angle output signals. Two radar transmitters provide radar signals in two different radar bands that are selectively transmitted by the antenna system as a radar beam. A radar receiver preprocesses radar return signals reflected from targets.

Abstract: By performing rotation and translation operations, a radar display converts a radar signal to radar image information expressed in a three-dimensional orthogonal coordinate system with horizontal, vertical, and depth coordinates related to a certain viewpoint. Terrain and target information is converted to the same coordinate system and combined with the radar image information, producing a realistic three-dimensional display. Clipping is performed in the depth direction to eliminate portions of the radar image disposed behind terrain or target images. Terrain and target images disposed behind the radar image are reduced in intensity, but not clipped. Perspective projection and zoom transformations may also be carried out.

Abstract: A Weather radar and map display system for use in aircraft includes a transmitter for transmitting radar signals outwardly from the aircraft, a receiver for receiving back reflected radar signals, a digitizer for digitizing the reflected radar signals, a processor for calculating the latitude and longitude coordinates of the locations in space from which the reflected radar signals were reflected based on detected range information of the reflected radar signals and detected heading, position and track information of the aircraft, and a storage device for storing the digitized signals and the latitude and longitude coordinates calculated for respective reflected radar signals.

Abstract: A weather radar display system and method for obtaining and storing radar return data for a plurality of horizontal and vertical sweeps, each horizontal sweep occurring at a different tilt angle and each vertical sweep occurring at a different azimuth angle. The radar return data is displayed as plan views in a plurality of separate display sections, each corresponding to a plurality of separate horizontal sweeps in one embodiment and to a plurality of separate vertical sweeps in a second embodiment. Radar return data in one display section (horizontal or vertical) is displayed with a variety of colors to represent precipitation intensity. Radar return data in remaining display section (horizontal or vertical) is displayed as a first color with edge returns displayed in second color to differentiate the remaining sections.

Abstract: Disclosed herein is a three-dimensional display radar, which comprises a radar transmitter-receiver unit for producing signals indicative of information about a bearing of a target, information about distance to the target and information about the received power reflected from the target, respectively, a display, a three-dimensional coordinate converter for converting the bearing information, the distance information and the received power information into signals indicative of both an X-Y coordinate and the height of the target, marker generator for generating range marker signals when the target is three-dimensionally represented on a screen of the display, and a video memory having storage addresses corresponding to respective pixels on the display and for storing the received power information at a storage address corresponding to the X-Y coordinate obtained from the three-dimensional coordinate converter and storing therein the marker signals generated from the marker generator, the video memory being f

Abstract: An automatic horizontal and vertical scanning radar for aircraft for displaying weather conditions includes an antenna system mounted in the aircraft for sweeping horizontally and vertically in response to horizontal and vertical drive signals and for transmitting radar signals forwardly of the aircraft and receiving back reflected radar signals, a receiver for digitizing received reflected radar signals, a storage unit for storing the digitized signals, a display unit responsive to display control signals for displaying a plan view image of weather conditions ahead of the aircraft represented by reflected radar signals received by the antenna system sweeping back and forth horizontally and a vertical view image of weather conditions represented by reflected radar signals received by the antenna system moving up and down vertically, and a control unit for supplying horizontal and vertical drive signals to the antenna system, and for producing control signals from the stored digitized signals.

Abstract: An image of a target (11) is produced by illumination of the target (11) with overlapping fields (18, 20) of wave energy, such as coherent light, producing an interference pattern (22) moving across the target. At least one pair (12) of sources (14, 16) wave energy provide the moving interference pattern (22). The scattered illumination reflected from the target is detected by a non-imaging receiver (24); a two dimensional spatial frequency map is recorded (30, 62), based upon the amplitude, frequency and phase of the illumination received; and a two dimensional image of the target is formed (32, 72) by applying a Fourier transform to the two dimensional frequency map.

Abstract: A computer method is disclosed for accurately transforming multiple radar observations of aircraft into a common coordinate system for air traffic control applications. The method involves a transformation from radar observables of the target slant range, azimuth and altitude to the target position coordinates in a stereographic system plane for display. The method includes a conformal coordinate conversion process from geodetic to conformal spherical coordinates followed by a conformal stereographic projection process onto a system display plane. The resulting display of aircraft position on the system plane is more accurate than has been available in the prior art.

Abstract: A bit map image is stored as a two-dimensional array with z axis set arbitrarily at unity. Total rotation transform and screen projection is then treated as a lumped equation due to multiplicative associativity so long as only one variable "V" is included in each lumped equation. The z-data (stored elevation values corresponding to each bit map x/y coordinate) is re-inserted as a later operation after the image has been partially transformed and projected.Full yaw, pitch, and translations from virtually any perspective viewpoint may be projected onto a multiplicity of screen shapes (conical, spherical, flat, etc.), with z data being inserted into a final output.

Abstract: A fanbeam inversion radar system (100) includes a frequency synthesizer (102) or other transmission means, a fanbeam antenna (104), an orientation sensor/controller (106) and a computer (110). The antenna is adapted for frequency scanning so that fanbeam position data is determined by the computer which controls the variable frequency synthesizer. By scanning a scene with fanbeams for each of a series of fanbeam orientations spanning 180.degree., a two-dimensional image reconstruction can be performed by algorithms well known in image processing fields.By presorting radar returns by delay time (at 112), multiple reconstructed images can be obtained corresponding to different ranges. By mixing (at 122) the synthesizer output with a reference from a local oscillator (120) and "beating" the return against the same reference by means of synchronous demodulators (132), Doppler sorting can provide multiple images with respective relative velocities.The radar system (100) uses serial frequency scanning.

Abstract: This radar system makes it possible to collect complete stereo data in a single pass by utilizing an orbiting, side looking, bi-static, synthetic aperture radar. This system utilizes at least two orbiting spacecraft in synchronous parallel orbits with each other and separated by a tether. A transmitter transmits radar signals to a planet's surface which are reflected back and received by two receivers, one carried by each spacecraft. When the signals are combined, the layover produces a three dimensional picture in which vertical height information may be determined.

Abstract: A passive range measurement device and method are described which utilizes a digitized image stream derived from images taken by a camera which is also part of the device. The device also includes a digital processor which operates on the image stream to extract the coefficients of an address modification function from which range to each point in the scene, relative camera-scene, and camera-platform orientations may be derived. The extraction process is based upon calculation of a vector field which describes the pixel-to-pixel misregistration between two images. Improvements in the modification function are found from global, then localized averages of the vector field. Thus, a topographic map of the scene which is referenced to the position of the camera and platform is created, and may be used to create a terrain following capability.