Imaging simulation of complex target active detection and optical cross section studies

2015 ◽  
Author(s):  
Yufang Yue ◽  
Feizhou Zhang ◽  
Jianzhu Zhang ◽  
Xiaogang Xie ◽  
Jianzhu An
Keyword(s):  
Cross Section ◽  
Optical Cross Section ◽  
Imaging Simulation ◽  
Complex Target ◽  
Active Detection

Dependence of the optical cross section of interface states on the photon energy at Si-SiO2 structures

1986 ◽  
Vol 168 (1-3) ◽  
pp. 665-671 ◽  
Author(s):  
A. Herms ◽  
J.R. Morante ◽  
J. Samitier ◽  
A. Cornet ◽  
P. Cartujo ◽  
...  
Keyword(s):  
Cross Section ◽  
Photon Energy ◽  
Interface States ◽  
Optical Cross Section

The Defect Structure of BaTiO3 Thin Films

1993 ◽  
Vol 310 ◽  
Author(s):  
L.A. Wills ◽  
B.W. Wessels
Keyword(s):  
Thin Films ◽  
Cross Section ◽  
Defect Structure ◽  
Oxygen Vacancies ◽  
Vacuum Annealing ◽  
Deep Level ◽  
Energy Levels ◽  
The Other ◽  
Optical Cross Section ◽  
Impurity Defects

AbstractThe defect structure of BaTiO3 thin films grown on (100) Si was examined using transient photocapacitance spectroscopy. The concentration, optical cross section and associated energy levels of both native and impurity defects in as-grown and annealed BaTiO3 films were evaluated. Deep level defects withpeak energies of Ev+1.8, Ev+2.4, Ev+2.7, Ev+3.0-3.1 and Ev+3.2-3.3 eV were observed in the as-grown films. Upon vacuum annealing, the concentration of the traps at Ev+3.0 and Ev+3.2 eV increased while the concentration of the traps at Ev+ 1.8 and Ev+2.4 eV decreased. The levels at Ev+3.0-3.1 and Ev+3.2-3.3 eV are attributed to oxygen vacancies. The other levels are tentatively ascribed to Fe and Fe related defects.

Research of Integration Calculation of Complex Target′s Laser Radar Cross Section

2014 ◽  
Vol 51 (2) ◽  
pp. 021404 ◽  
Author(s):  
张昊 Zhang Hao ◽  
李建周 Li Jianzhou ◽  
陈昶 Chen Chang
Keyword(s):  
Cross Section ◽  
Radar Cross Section ◽  
Laser Radar ◽  
Complex Target

scholarly journals An UWB Physical Optics Approach for Fresnel-Zone RCS Measurements on a Complex Target at Non-Normal Incidence

Sensors ◽  
2019 ◽  
Vol 19 (24) ◽  
pp. 5454
Author(s):  
Ilie Valentin Mihai ◽  
Razvan Tamas ◽  
Ala Sharaiha
Keyword(s):  
Cross Section ◽  
Fresnel Zone ◽  
Normal Incidence ◽  
Radar Cross Section ◽  
Physical Optics ◽  
Fast Method ◽  
Field Zone ◽  
Fresnel Region ◽  
Receiving Antenna ◽  
Complex Target

In this paper, we propose a fast method for measuring the radar cross section of a complex target at non-normal incidences and Fresnel region antenna-to-target distances. The proposed method relies both on the physical optics approach and on averaging the field distribution over the transmitting and receiving antenna apertures. The ratio between the analytical expression of the radar cross section at far-field and Fresnel region results in a field-zone extrapolation factor. The RCS resulting from the scattering parameters measured at Fresnel region distances is then corrected with that field-zone extrapolation factor. The method is suitable to be used in a perturbed, multipath environment by applying the distance averaging technique, coupling subtraction or time gating. Our technique requires a very simple measuring configuration consisting of two horn antennas and a vector network analyzer. The experimental validation of the proposed technique demonstrates reasonable agreement with simulated radar cross section at non-normal incidence.

scholarly journals Enhancing the optical cross section of quantum antenna

2017 ◽  
Vol 95 (1) ◽  
Author(s):  
Jingfeng Liu ◽  
Ming Zhou ◽  
Lei Ying ◽  
Xuewen Chen ◽  
Zongfu Yu
Keyword(s):  
Cross Section ◽  
Optical Cross Section

Dependence of the optical cross section of interface states on the photon energy at Si-SiO2 structures

1986 ◽  
Vol 168 (1-3) ◽  
pp. A137
Author(s):  
A. Hermas ◽  
J.R. Morante ◽  
J. Samitier ◽  
A. Cornet ◽  
P. Cartujo ◽  
...  
Keyword(s):  
Cross Section ◽  
Photon Energy ◽  
Interface States ◽  
Optical Cross Section

Load-based approaches for modelling visual clarity in streams at regional scale

2013 ◽  
Vol 67 (5) ◽  
pp. 1092-1096 ◽  
Author(s):  
A. H. Elliott ◽  
R. J. Davies-Colley ◽  
A. Parshotam ◽  
D. Ballantine
Keyword(s):  
Water Quality ◽  
Attenuation Coefficient ◽  
Cross Section ◽  
Water Discharge ◽  
Regional Scale ◽  
Rock Types ◽  
Beam Attenuation ◽  
Optical Cross Section ◽  
Water Volumes ◽  
Beam Attenuation Coefficient

Reduction of visual clarity in streams by diffuse sources of fine sediment is a cause of water quality impairment in New Zealand and internationally. In this paper we introduce the concept of a load of optical cross section (LOCS), which can be used for load-based management of light-attenuating substances and for water quality models that are based on mass accounting. In this approach, the beam attenuation coefficient (units of m–1) is estimated from the inverse of the visual clarity (units of m) measured with a black disc. This beam attenuation coefficient can also be considered as an optical cross section (OCS) per volume of water, analogous to a concentration. The instantaneous ‘flux’ of cross section is obtained from the attenuation coefficient multiplied by the water discharge, and this can be accumulated over time to give an accumulated ‘load’ of cross section (LOCS). Moreover, OCS is a conservative quantity, in the sense that the OCS of two combined water volumes is the sum of the OCS of the individual water volumes (barring effects such as coagulation, settling, or sorption). The LOCS can be calculated for a water quality station using rating curve methods applied to measured time series of visual clarity and flow. This approach was applied to the sites in New Zealand's National Rivers Water Quality Network (NRWQN). Although the attenuation coefficient follows roughly a power relation with flow at some sites, more flexible loess rating curves are required at other sites. The hybrid mechanistic–statistical catchment model SPARROW (SPAtially Referenced Regressions On Watershed attributes), which is based on a mass balance for mean annual load, was then applied to the NRWQN dataset. Preliminary results from this model are presented, highlighting the importance of factors related to erosion, such as rainfall, slope, hardness of catchment rock types, and the influence of pastoral development on the load of optical cross section.

Electronic Transitions in Mixed Phase Crystalline/Amorphous Silicon in the Low Crystalline Fraction Regime

1999 ◽  
Vol 557 ◽  
Author(s):  
J. David Cohen ◽  
Daewon Kwon ◽  
Chih-Chiang Chen ◽  
Hyun-Chul Jin ◽  
Eric Hollar ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Cross Section ◽  
Optical Transition ◽  
Electronic Transitions ◽  
Crystalline Fraction ◽  
Silicon Matrix ◽  
Transient Photocurrent ◽  
Dc Reactive Magnetron Sputtering ◽  
Optical Cross Section ◽  
Low Crystalline

AbstractAmorphous silicon films were prepared by dc reactive magnetron sputtering under conditions approaching the phase transition to microcrystallinity. Using TEM imaging these films were found to contain clusters of 5 to 50 nm sized Si crystallites embedded in an amorphous silicon matrix. Photocapacitance and transient photocurrent sub-band-gap optical spectra of this material appear to consist of a superposition of a spectrum typical of amorphous silicon together with an optical transition, with a threshold near 1. 1eV, that exhibits a very large optical cross section. This transition arises from valence band electrons being optically inserted into empty levels lying within the amorphous silicon mobility gap. Using modulated photocurrent methods we have determined that these states also dominate the electron deep trapping in this material. We argue that these states arise from defects at the crystalline-amorphous boundary.

Photo-induced Dissociation and Optical Cross Section of Si-H and S-H Complexes in GaAs and AlGaAs

2002 ◽  
Vol 719 ◽  
Author(s):  
M. Barbé ◽  
F. Bailly ◽  
J. Chevallier ◽  
S. Silvestre ◽  
D. Loridant-Bernard ◽  
...  
Keyword(s):  
Carrier Concentration ◽  
Cross Section ◽  
Cross Sections ◽  
Electronic Excitation ◽  
Surface States ◽  
Antibonding State ◽  
Free Carriers ◽  
Bonding State ◽  
Uv Illumination ◽  
Optical Cross Section

AbstractIn GaAs, (Si,H) complexes are efficiently dissociated at 300 K by photons with energies above 3.5 eV. Their optical cross-section is 10-19-10-18 cm2. This dissociation is the result of an electronic excitation of the Si-H bond of the complex from a bonding state to an antibonding state. (Si,H) and (S,H) complexes in AlGaAs alloys are also dissociated under UV illumination with optical cross-sections similar to GaAs. In passivated 2D AlGaAs-GaAs heterostructures, the evolution of the extra sheet carrier concentration at low photon densities presents a loss of free carriers attributed to the filling of surface states. In AlGaAs and in 2D AlGaAs-GaAs heterostructures, the replacement of hydrogen by deuterium in the complexes shows that the (Si,D) and (S,D) complexes are significantly more stable than the (Si,H) and (S,H) complexes as previously found in GaAs:Si,H.

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