Probing insect backscatter cross-section and melanization using kHz optical remote detection system

2016 ◽  
Author(s):  
Alem K. Gebru ◽  
Mikkel Brydegaard ◽  
Erich Rohwer ◽  
Pieter Neethling
Keyword(s):  
Cross Section ◽  
Detection System ◽  
Remote Detection ◽  
Backscatter Cross Section

Probing insect backscatter cross section and melanization using kHz optical remote detection system

2017 ◽  
Vol 11 (1) ◽  
pp. 016015 ◽  
Author(s):  
Alem Gebru ◽  
Mikkel Brydegaard ◽  
Erich Rohwer ◽  
Pieter Neethling
Keyword(s):  
Cross Section ◽  
Detection System ◽  
Remote Detection ◽  
Backscatter Cross Section

scholarly journals Radar efficiency and the calculation of decade-long PMSE backscatter cross-section for the Resolute Bay VHF radar

2009 ◽  
Vol 27 (4) ◽  
pp. 1643-1656 ◽  
Author(s):  
N. Swarnalingam ◽  
W. K. Hocking ◽  
P. S. Argall
Keyword(s):  
Cross Section ◽  
Great Level ◽  
Vhf Radar ◽  
Radar Echoes ◽  
Summer Echoes ◽  
Resolute Bay ◽  
Absolute Measurements ◽  
Coherent Radar ◽  
Backscatter Cross Section

Abstract. The Resolute Bay VHF radar, located in Nunavut, Canada (75.0° N, 95.0° W) and operating at 51.5 MHz, has been used to investigate Polar Mesosphere Summer Echoes (PMSE) since 1997. PMSE are a unique form of strong coherent radar echoes, and their understanding has been a challenge to the scientific community since their discovery more than three decades ago. While other high latitude radars have recorded strong levels of PMSE activities, the Resolute Bay radar has observed relatively lower levels of PMSE strengths. In order to derive absolute measurements of PMSE strength at this site, a technique is developed to determine the radar efficiency using cosmic (sky) noise variations along with the help of a calibrated noise source. VHF radars are only rarely calibrated, but determination of efficiency is even less common. Here we emphasize the importance of efficiency for determination of cross-section measurements. The significant advantage of this method is that it can be directly applied to any MST radar system anywhere in the world as long as the sky noise variations are known. The radar efficiencies for two on-site radars at Resolute Bay are determined. PMSE backscatter cross-section is estimated, and decade-long PMSE strength variations at this location are investigated. It was noticed that the median of the backscatter cross-section distribution remains relatively unchanged, but over the years a great level of variability occurs in the high power tail of the distribution.

Regularizing method for the determination of the backscatter cross section in lidar data

2009 ◽  
Vol 26 (5) ◽  
pp. 1071 ◽  
Author(s):  
Yanfei Wang ◽  
Jianzhong Zhang ◽  
Andreas Roncat ◽  
Claudia Künzer ◽  
Wolfgang Wagner
Keyword(s):  
Cross Section ◽  
Lidar Data ◽  
Backscatter Cross Section

77 GHz offset reflectarray for FOD detection on airport runways

2012 ◽  
Vol 4 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Karim Mazouni ◽  
Christian Pichot ◽  
Jérôme Lantéri ◽  
Jean-Yves Dauvignac ◽  
Claire Migliaccio ◽  
...  
Keyword(s):  
Cross Section ◽  
Frequency Band ◽  
Detection System ◽  
Radar Cross Section ◽  
High Gain ◽  
Foreign Object ◽  
Maximum Gain ◽  
Aperture Efficiency ◽  
Reflectarray Antenna ◽  
77 Ghz

In designing a Foreign Object Debris (FOD) detection system on airport runways, this paper deals with the performance of a 77 GHz reflectarray antenna (RA). Debris may be very small and have low radar cross section (RCS), leading to design a high gain primary-fed offset RA. To minimize the aperture blockage, the main radiation lobe is in the specular direction. The antenna has a maximum gain of 40 dBi and aperture efficiency of 50% over the frequency band 76–77 GHz. First measurements using a 77 GHz radar module were carried out on pavement.

HELICITY DEPENDENT PHOTOPRODUCTION ON THE DEUTERON AND THE GDH SUM RULE ON THE NEUTRON

2010 ◽  
Vol 19 (05n06) ◽  
pp. 1009-1020
Author(s):  
◽  
PAOLO PEDRONI
Keyword(s):  
Cross Section ◽  
State Of The Art ◽  
Detection System ◽  
Detailed Comparison ◽  
Photoabsorption Cross Section ◽  
Sum Rule ◽  
Circularly Polarized ◽  
Polarized Deuterons ◽  
System A ◽  
Gdh Sum Rule

The first measurements of the helicity dependence for the γd reactions were carried out at MAMI (Mainz) in the energy range E γ=200-800 MeV . The experiment used a 4π detection system, a circularly polarized tagged photon beam and a frozen spin target which provided longitudinally polarized deuterons. Results on both the total inclusive photoabsorption cross section and of the πNN channels will be presented. These data give important information about the the Gerasimov-Drell-Hearn sum rule on the neutron and allow a detailed comparison with state-of-the-art calculations of the γd interaction.

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