Topic
Corner reflector
About: Corner reflector is a research topic. Over the lifetime, 1825 publications have been published within this topic receiving 12446 citations. The topic is also known as: radar reflector.
Papers published on a yearly basis
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Papers
TL;DR: In this article, a technique that uses the radar return from natural targets and at least one trihedral corner reflector to calibrate compressed polarimetric radar data is described, which is based on the theoretical result that for natural targets with azimuthal symmetry the copolarized and crosspolarized components of the scattering matrix are uncorrelated.
Abstract: A technique that uses the radar return from natural targets and at least one trihedral corner reflector to calibrate compressed polarimetric radar data is described. Calibration for relative amplitude, relative phase, absolute amplitude, and system crosstalk is addressed. The crosstalk calibration method is based on the theoretical result that for natural targets with azimuthal symmetry the copolarized and crosspolarized components of the scattering matrix are uncorrelated, and the method does not require any external calibration targets to be deployed before imaging. Because compressed data are used, one is forced to model the transmitting and receiving systems as reciprocal. Even though the inferred transmit and receive matrices are not each simply related to the physical transmitter and receiver, the true Stokes matrix for each pixel in an image can be accurately determined by this approach. The method is illustrated by estimating the crosstalk parameters of the NASA/JPL aircraft for different types of terrain and for two frequencies. For the C-band system, the crosstalk is less than -20 dB for all ranges in the images. The crosstalk of the L-band system is a function of range, however, and may be as poor as -10 dB in the near range, leading to a noticeable distortion of the polarization signatures. >
414 citations
TL;DR: In this article, a simple expression for the terrain backscatter coefficient is derived in terms of the integrated power of an adjacent known radar reflector in a synthetic aperture radar (SAR) image.
Abstract: A simple expression for the terrain backscatter coefficient is derived in terms of the integrated power of an adjacent known radar reflector in a synthetic aperture radar (SAR) image. It is shown that this technique for SAR image calibration is independent of the radar system focus or partial coherence and thereby possesses an important advantage over the usual technique, which relies on an estimate of the peak of the reflector impulse response. Results from airborne SAR overflights of corner reflectors and active radar calibrators are used to demonstrate the validity and consistency of the method and to show that the method is robust under defocus caused by an incorrect FM rate or inadequate motion compensation of data collected during turbulence. It is also shown that the fading errors associated with the integral method are comparable to or slightly worse than those associated with the peak estimation method. However, this small disadvantage is outweighed by the fact that the integral method is independent of actual resolution. >
196 citations
TL;DR: The Van Atta reflector array as mentioned in this paper is an array in which the elements are interconnected to reradiate received energy back in the direction of arrival, and it is sensitive only to incident waves in the frequency band of and having the polarization of the dipoles.
Abstract: The Van Atta reflector array is an array in which the elements are interconnected to reradiate received energy back in the direction of arrival. Scattering cross section measurements on a four-by-four Van Atta array of sixteen dipoles are presented. This array reflects over a wider angle than the typical corner reflector, but is sensitive only to incident waves in the frequency band of and having the polarization of the dipoles.
181 citations
TL;DR: The performance of TIL coherent beam combining and atmospheric mitigation was significantly increased by using an SPGD control variation that accounts for the round-trip propagation delay (delayed SPGD).
Abstract: We demonstrate coherent combining (phase locking) of seven laser beams emerging from an adaptive fiber-collimator array over a 7 km atmospheric propagation path using a target-in-the-loop (TIL) setting. Adaptive control of the piston and the tip and tilt wavefront phase at each fiber-collimator subaperture resulted in automatic focusing of the combined beam onto an unresolved retroreflector target (corner cube) with precompensation of quasi-static and atmospheric turbulence-induced phase aberrations. Both phase locking (piston) and tip–tilt control were performed by maximizing the target-return optical power using iterative stochastic parallel gradient descent (SPGD) techniques. The performance of TIL coherent beam combining and atmospheric mitigation was significantly increased by using an SPGD control variation that accounts for the round-trip propagation delay (delayed SPGD).
158 citations
TL;DR: The Orthogonal frequency-division multiplexing signal coding and system architecture were implemented to achieve radar and data communication functionalities and shows good promise as a multifunctional software-defined sensor which can be used in radar sensor networks.
Abstract: Orthogonal frequency-division multiplexing (OFDM) signal coding and system architecture were implemented to achieve radar and data communication functionalities. The resultant system is a software-defined unit, which can be used for range measurements, radar imaging, and data communications. Range reconstructions were performed for ranges up to 4 m using trihedral corner reflectors with approximately 203 m of radar cross section at the carrier frequency; range resolution of approximately 0.3 m was demonstrated. Synthetic aperture radar (SAR) image of a single corner reflector was obtained; SAR signal processing specific to OFDM signals is presented. Data communication tests were performed in radar setup, where the signal was reflected by the same target and decoded as communication data; bit error rate of was achieved at 57 Mb/s. The system shows good promise as a multifunctional software-defined sensor which can be used in radar sensor networks.
156 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2025 | 7 |
| 2024 | 26 |
| 2023 | 31 |
| 2022 | 56 |
| 2021 | 46 |
| 2020 | 63 |