Directed Energy Beam Jitter Mitigation Using the Line-of-Sight Reference Frame

2011 ◽  
Author(s):  
Nicholas C. Dunn
Keyword(s):  
Reference Frame ◽  
Line Of Sight ◽  
Energy Beam ◽  
Directed Energy

Large-scale, high-resolution maps of interseismic strain accumulation from Sentinel-1, and incorporation of along-track measurements

2021 ◽  
Author(s):  
Andy Hooper ◽  
Pawan Piromthong ◽  
Tim Wright ◽  
Jonathan Weiss ◽  
Milan Milan Lazecky ◽  
...  
Keyword(s):  
Time Series ◽  
High Resolution ◽  
Velocity Field ◽  
Reference Frame ◽  
Line Of Sight ◽  
Tectonic Deformation ◽  
Low Resolution ◽  
Gnss Measurements ◽  
Along Track ◽  
East West

<p>High-resolution geodetic measurements of crustal deformation from InSAR have the potential to provide crucial constraints on a region’s tectonics, geodynamics and seismic hazard. Here, we present a high-resolution crustal velocity field for the Alpine-Himalayan Seismic Belt (AHSB) derived from Sentinel-1 InSAR and GNSS. We create time series and average velocities from ~220,000 interferograms covering an area of 15 million km<sup>2</sup>, with an average of 170 acquisitions per measurement point. We tie the velocities to a Eurasian reference frame by jointly inverting the InSAR data with GNSS data to produce a low-resolution model of 3D surface velocities. We then use the referenced InSAR velocities to invert for high-resolution east-west and sub-vertical velocity fields for the entire region. The sub-vertical velocities, which also include a small component of north-south motion, are dominated by non-tectonic deformation, such as subsidence due to water extraction. The east-west velocity field, however, reveals the tectonics of the AHSB with an unprecedented level of detail.</p><p>The approach described above only provides good constraints on horizontal displacement in the east-west direction, with the north-south component provided by low-resolution GNSS measurements. Sentinel-1 does also have the potential to provide measurements that are sensitive to north-south motion, through exploitation of the burst overlap areas produced by the TOPS acquisition mode. These along-track measurements have lower precision than line-of-sight InSAR and are more effected by ionospheric noise, but have the advantage of being almost insensitive to tropospheric noise. We present a time series approach to tease out the subtle along-track signals associated with interseismic strain. Our approach includes improvements to the mitigation of ionospheric noise and we also investigate different filtering approaches to optimize the reduction of decorrelation noise. In contrast to the relative measurements of line-of-sight InSAR, these along-track measurements are automatically provided in a global reference frame. We present results from five years of data for the West-Lut Fault in eastern Iran and the Chaman Fault in Pakistan and Afghanistan. Our results agree well with independent GNSS measurements; however, the denser coverage of the technique allows us to also detect the variation in slip rate along the faults.</p><p>Finally, we demonstrate the improvement in the resolution of horizontal strain rates when including these along-track measurements, in addition to the conventional line-of-sight InSAR measurements.</p>

scholarly journals Directed Energy Beam Weapons the Dawn of a New Military Age

2021 ◽  
pp. 1-8
Author(s):  
Bahman Zohuri ◽  
◽  
Masoud Moghaddam ◽  
Keyword(s):  
High Power ◽  
Short Review ◽  
Time Frame ◽  
High Energy ◽  
Department Of Energy ◽  
Scalar Wave ◽  
Long Distance ◽  
Energy Beam ◽  
Microwave Beam ◽  
Directed Energy

Aftermath of “Havana Syndrome” that took place in Cuba, at around 2016 – 2017 time-frame, where American diplomat got mysterious sickness, the dawn of a new military age was born, where directed energy weapons in form waves are now in play. Among concerned government agencies, they still cannot find the source of the sickness except, stating that whatever was the cause, it is unnatural source, but rather man-made weapons in form of high microwave beam weapon. However, this author with this short review is going to show a different perspective of directed energy beam weapons, knowingly that this type weapons are not anything new and scientist and engineer, at national laboratories, department of energy and defense level including some universities nation-wide have been involved with research and development of such direct energy weapons. The battles of tomorrow are not going to take place with speed of bullet or artillery shell, but rather will be fought with speed of light and electron, and that is why the new military age presents itself along with new innovative technologies that is discussed here in this short review. For purpose beam weapons as directed energy we are not taking under consideration, the high power energy laser, since it is beyond the scope of this short review, however we focus on wave frequencies that are falling within high power microwave bandwidth and we introduce another beam weapon’s concept that is known as scalar wave, which we know it as longitudinal scalar wave, that possibly can justify the above sickness caused by the unnatural source, which falls within a man-made source of energy that can travel long distance and penetrated even through Faraday’s cage and any other obstacle in front of very similar to behavior and characteristic of soliton wave. Whatever covert sound or high energy acoustic or wave weapon this man-made phenomena was or is will be discussed in this report with some means of science physics behind it. All scientific discussion in this short review is presentation of this author period

scholarly journals Ground-based detection of a cloud of methanol from Enceladus: when is a biomarker not a biomarker?

2017 ◽  
Vol 18 (1) ◽  
pp. 25-32 ◽  
Author(s):  
E. Drabek-Maunder ◽  
J. Greaves ◽  
H. J. Fraser ◽  
D. L. Clements ◽  
L.-N. Alconcel
Keyword(s):  
Radiative Transfer ◽  
Reference Frame ◽  
Line Of Sight ◽  
Beam Diameter ◽  
Parent Species ◽  
Secondary Product ◽  
Chemical Interactions ◽  
Liquid Environment ◽  
Surface Ocean ◽  
Gas Cloud

ABSTRACTSaturn's moon Enceladus has vents emerging from a sub-surface ocean, offering unique probes into the liquid environment. These vents drain into the larger neutral torus in orbit around Saturn. We present a methanol (CH3OH) detection observed with IRAM 30-m from 2008 along the line-of-sight through Saturn's E-ring. Additionally, we also present supporting observations from the Herschel public archive of water (ortho-H2O; 1669.9 GHz) from 2012 at a similar elongation and line-of-sight. The CH3OH 5(1,1)-4(1,1) transition was detected at 5.9σ confidence. The line has 0.43 km s−1 width and is offset by +8.1 km s−1 in the moon's reference frame. Radiative transfer models allow for gas cloud dimensions from 1750 km up to the telescope beam diameter ~73 000 km. Taking into account the CH3OH lifetime against solar photodissociation and the redshifted line velocity, there are two possible explanations for the CH3OH emission: methanol is primarily a secondary product of chemical interactions within the neutral torus that: (1) spreads outward throughout the E-ring or (2) originates from a compact, confined gas cloud lagging Enceladus by several km s−1. We find either scenario to be consistent with significant redshifted H2O emission (4σ) measured from the Herschel public archive. The measured CH3OH:H2O abundance (>0.5%) significantly exceeds the observed abundance in the direct vicinity of the vents (~0.01%), suggesting CH3OH is likely chemically processed within the gas cloud with methane (CH4) as its parent species.

Study on a New Nonlinear H∞ Guidance Law for Autonomous Underwater Vehicle

2011 ◽  
Vol 219-220 ◽  
pp. 362-365
Author(s):  
Hao Ding ◽  
Kui Ping Liu ◽  
Wen Li You
Keyword(s):  
Reference Frame ◽  
Relative Motion ◽  
High Performance ◽  
Autonomous Underwater Vehicle ◽  
Normal Load ◽  
Underwater Vehicle ◽  
Target Line ◽  
Line Of Sight ◽  
Guidance Law ◽  
Target Pursuit

The key for Autonomous Underwater Vehicle (AUV) to implement target pursuit is to design high performance guidance law. The globose reference frame is adopted, and equations for 3-D relative motion between AUV and the target are built. Then the H∞ theory is used, and a new AUV nonlinear H∞ guidance law is obtained by solving Hamilton-Jacobi inequation. Simulation is taken on to verify the performance of H∞ guidance law. And the results show that the H∞ guidance law can help AUV overtake the target in less time, and the azimuth and pitching angle of the target line of sight are always staying at the initial numerical values. Furthermore, the normal load decreases to zero gradually. So the guidance law is effective for AUV to pursuit target.

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