HIGH RESOLUTION MONOPULSE RADAR TRACKING SYSTEM

1992 ◽  
Vol 02 (04) ◽  
pp. 305-321
Author(s):  
Y.A. ALSAKA ◽  
L.A. YOUNG ◽  
M. HAMID
Keyword(s):  
High Resolution ◽  
Cross Sections ◽  
Tracking System ◽  
Error Function ◽  
Geometric Center ◽  
Radar Cross Sections ◽  
High Resolution Radar ◽  
Angle Tracking ◽  
Crosscorrelation Function ◽  
Frequency Pulse

High resolution radar techniques are applied to the problem of resolving a multiple target array and locating its geometric center without the usual biasing toward the brightest scatterer. This result is accomplished using monopulse radar techniques combined with high resolution stepped frequency pulse train signal processing in an angle tracking noncoherent high resolution radar. The center of each uniquely separated pair of point targets is calculated by examining the crosscorrelation function of the sum and difference channels. The autocorrelation of the sum channel is used to normalize the crosscorrelation data thereby eliminating the effects of the different targets’ radar cross sections (RCS). The zero separation term of the error function (dc term) remains biased toward the bigger scatterer, even after normalization. The nonzero terms (ac terms) are the cross range distances from the antenna’s boresight to each scatterer and are independent of their RCS. By simply dropping the zero separation term and averaging the remaining terms together, the aimpoint becomes the unbiased geometric center of the array.

An Analysis of Dissociation of Molecules in a High Resolution Electron Microscope

1973 ◽  
Vol 31 ◽  
pp. 486-487
Author(s):  
Mihir Parikh
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Cross Sections ◽  
Resolving Power ◽  
Peak Intensity ◽  
Molecular Film ◽  
Resolution Electron ◽  
Dissociation Cross Section ◽  
High Resolution Electron Microscope ◽  
The Stability

It is well known that the resolution of bio-molecules in a high resolution electron microscope depends not just on the physical resolving power of the instrument, but also on the stability of these molecules under the electron beam. Experimentally, the damage to the bio-molecules is commo ly monitored by the decrease in the intensity of the diffraction pattern, or more quantitatively by the decrease in the peaks of an energy loss spectrum. In the latter case the exposure, EC, to decrease the peak intensity from IO to I’O can be related to the molecular dissociation cross-section, σD, by EC = ℓn(IO /I’O) /ℓD. Qu ntitative data on damage cross-sections are just being reported, However, the microscopist needs to know the explicit dependence of damage on: (1) the molecular properties, (2) the density and characteristics of the molecular film and that of the support film, if any, (3) the temperature of the molecular film and (4) certain characteristics of the electron microscope used

Comparison of ultra high resolution immersion lens CFESEM and TEM for imaging of semiconductor devices

1990 ◽  
Vol 48 (4) ◽  
pp. 622-623
Author(s):  
Terrence Reilly ◽  
Al Pelillo ◽  
Barbara Miner
Keyword(s):  
High Resolution ◽  
Sample Preparation ◽  
Cross Sections ◽  
Semiconductor Devices ◽  
Ion Milling ◽  
Observation Area ◽  
Transmission Electron ◽  
Milling Machines ◽  
Resolution Imaging ◽  
Electron Microscopes

The use of transmission electron microscopes (TEM) has proven to be very valuable in the observation of semiconductor devices. The need for high resolution imaging becomes more important as the devices become smaller and more complex. However, the sample preparation for TEM observation of semiconductor devices have generally proven to be complex and time consuming. The use of ion milling machines usually require a certain degree of expertise and allow a very limited viewing area. Recently, the use of an ultra high resolution "immersion lens" cold cathode field emission scanning electron microscope (CFESEM) has proven to be very useful in the observation of semiconductor devices. Particularly at low accelerating voltages where compositional contrast is increased. The Hitachi S-900 has provided comparable resolution to a 300kV TEM on semiconductor cross sections. Using the CFESEM to supplement work currently being done with high voltage TEMs provides many advantages: sample preparation time is greatly reduced and the observation area has also been increased to 7mm. The larger viewing area provides the operator a much greater area to search for a particular feature of interest. More samples can be imaged on the CFESEM, leaving the TEM for analyses requiring diffraction work and/or detecting the nature of the crystallinity.

Variational estimation of radar cross-sections

1990 ◽  
Vol 137 (4) ◽  
pp. 237 ◽  
Author(s):  
D.A. Edwards ◽  
R.A. McCulloch ◽  
W.T. Shaw
Keyword(s):  
Cross Sections ◽  
Radar Cross Sections

REDUCTION OF ASPECT DEPENDENT SPECKLE FLUCTUATIONS IN HIGH-RESOLUTION RADAR RANGE PROFILES

2010 ◽  
Vol 69 (8) ◽  
pp. 687-698 ◽  
Author(s):  
V. M. Orlenko ◽  
P. A. Molchanov ◽  
A. V. Totsky ◽  
Karen O. Egiazarian ◽  
J. T. Astola
Keyword(s):  
High Resolution ◽  
High Resolution Radar

FIB Enhancement of Mechanically Polished Cross-sections

2019 ◽  
Author(s):  
Becky Holdford
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Scanning Electron Microscope ◽  
Cross Sections ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
High Resolution Imaging ◽  
Chemical Attack ◽  
Resolution Imaging ◽  
Scanning Electron

Abstract On mechanically polished cross-sections, getting a surface adequate for high-resolution imaging is sometimes beyond the analyst’s ability, due to material smearing, chipping, polishing media chemical attack, etc.. A method has been developed to enable the focused ion beam (FIB) to re-face the section block and achieve a surface that can be imaged at high resolution in the scanning electron microscope (SEM).

Cross Section Analysis of Cu Filled TSVs Based on High Throughput Plasma-FIB Milling

2012 ◽  
Author(s):  
Frank Altmann ◽  
Jens Beyersdorfer ◽  
Jan Schischka ◽  
Michael Krause ◽  
German Franz ◽  
...  
Keyword(s):  
High Resolution ◽  
Cross Section ◽  
High Throughput ◽  
Cross Sections ◽  
Electron Backscatter Diffraction ◽  
Grain Structure ◽  
Electron Backscatter ◽  
Section Surface ◽  
Backscatter Diffraction ◽  
Section Analysis

Abstract In this paper the new Vion™ Plasma-FIB system, developed by FEI, is evaluated for cross sectioning of Cu filled Through Silicon Via (TSV) interconnects. The aim of the study presented in this paper is to evaluate and optimise different Plasma-FIB (P-FIB) milling strategies in terms of performance and cross section surface quality. The sufficient preservation of microstructures within cross sections is crucial for subsequent Electron Backscatter Diffraction (EBSD) grain structure analyses and a high resolution interface characterisation by TEM.

scholarly journals High-resolution 2D Raman mapping of mono- and bicomponent filament cross-sections

Polymer ◽  
2021 ◽  
pp. 124011 ◽  
Author(s):  
E. Perret ◽  
O. Braun ◽  
K. Sharma ◽  
S. Tritsch ◽  
R. Muff ◽  
...  
Keyword(s):  
High Resolution ◽  
Cross Sections ◽  
Raman Mapping
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