This technology must be coupled with highly sensitive detectors of eye-safe wavelengths. To measure Doppler information requires a different type of detection scheme than is used for spatial imaging. The returned laser energy must be mixed with a local oscillator in a heterodyne system to allow extraction of the Doppler shift.
EP2198391A1 - Long distance multimodal biometric system and method - Google Patents
The system architecture of 3-D, Multi-wave and Multi-band, Imaging radar is shown in the figure. Synthetic-aperture radar SAR is a form of radar which moves a real aperture or antenna through a series of positions along the objects to provide distinctive long-term coherent-signal variations.
This can be used to obtain higher resolution. SARs produce a two-dimensional 2-D image.
JRM Vol p () | Fuji Technology Press: academic journal publisher
One dimension in the image is called range and is a measure of the "line-of-sight" distance from the radar to the object. Range is determined by measuring the time from transmission of a pulse to receiving the echo from a target. Also, range resolution is determined by the transmitted pulse width. The other dimension is called azimuth and is perpendicular to range. The ability of SAR of producing relatively fine azimuth resolution makes it different from other radars.
To obtain fine azimuth resolution, a physically large antenna is needed to focus the transmitted and received energy into a sharp beam. The sharpness of the beam defines the azimuth resolution.
Citations per year
An airborne radar could collect data while flying this distance and process the data as if it came from a physically long antenna. The distance the aircraft flies in synthesizing the antenna is known as the synthetic aperture. A narrow synthetic beamwidth results from the relatively long synthetic aperture, which gets finer resolution than a smaller physical antenna. Inverse synthetic aperture radar ISAR is another kind of SAR system which can produce high-resolution on two- and three-dimensional images.
Approaches for Stereo Matching
An ISAR system consists of a stationary radar antenna and a target scene that is undergoing some motion. ISAR is theoretically equivalent to SAR in that high-azimuth resolution is achieved via relative motion between the sensor and object, yet the ISAR moving target scene is usually made up of non cooperative objects. ISAR technology uses the movement of the target rather than the emitter to make the synthetic aperture.
ISAR radars are commonly used on vessels or aircraft and can provide a radar image of sufficient quality for target recognition. The ISAR image is often adequate to discriminate between various missiles, military aircraft, and civilian aircraft. Monopulse radar 3-D imaging technique uses 1-D range image and monopulse angle measurement to get the real coordinates of each scatterer. Monopulse radar 3-D imaging utilizes the ISAR techniques to separate scatterers in the Doppler domain and perform monopulse angle measurement.
Monopulse radar 3-D imaging can obtain the 3 views of 3-D objects by using any two of the three parameters obtained from the azimuth difference beam, elevation difference beam and range measurement, which means the views of front, top and side can be azimuth-elevation, azimuth-range and elevation-range, respectively. Monopulse imaging generally adapts to near-range targets, and the image obtained by monopulse radar 3-D imaging is the physical image which is consistent with the real size of the object.
From Wikipedia, the free encyclopedia. See also: Radar display and Radar astronomy.
- Making Meaning by Making Connections.
- EJB 3 in Action, 2nd Edition.
- Expedition to the Barrier Peaks (Advanced Dungeons & Dragons module S3).
Main article: Lidar. Main article: Synthetic aperture radar.
Main article: Inverse synthetic aperture radar. Main article: Monopulse radar.
Retrieved Advanced Radar Signal and Data Processing. Sachs; M. Drutarovsky; D. Kocur Nov Frequenz Journal. Bibcode : Freq International Journal of Image and Vision Computing.
Epub Active Computer Vision By Cooperative Focus And Stereo 1989
The 3rd European Radar Conference : — Archived from the original on June 4, Conference Proceedings. Sign in. Get my own profile Cited by View all All Since Citations h-index 38 18 iindex 78 Robotics Artificial Intelligence. Articles Cited by. International Journal of Computer Vision 1 3 , , Proceedings, International Conference on Robotics and Automation, , International Journal of computer vision 11 2 , , The International Journal of Robotics Research 18 7 , , Articles 1—20 Show more.
Help Privacy Terms. M Hebert, E Krotkov Image and vision computing 10 3 , , Computer 22 6 , , Mobile robot localization using a single image E Krotkov Proceedings, International Conference on Robotics and Automation, , Depth from scattering F Cozman, E Krotkov cvpr 31, , Journal of neuroscience methods , , Active vision for reliable ranging: Cooperating focus, stereo, and vergence E Krotkov, R Bajcsy International Journal of computer vision 11 2 , ,