Bistatic SAR for Building Wall Material Characterisation

© Cranfield University 2020. All rights reserved. No part of this publication may be reproduced without the written permission of the copyright ownerThis thesis addresses the problem of using radar to extract interpretable information concerning both the structure and electrical properties of a wall, and the environment behind it. This is broken down into two subproblems: how to determine the thickness and electromagnetic properties of the wall without being in direct contact with it, and how to obtain the most accurate images of what lies beyond the wall. Existing research in the area is evaluated and a theoretical study is presented on the use of monostatic, bistatic, and multistatic Synthetic Aperture Radar (SAR) in both one and two dimensional apertures. New methods of determining the wall properties are evaluated by both computer simulation and with laboratory radar measurements, where a wall of concrete blocks is constructed. The robustness of the asymmetric SAR geometry approach is evaluated with the addition of complex objects placed behind the wall. The uncertainty associated with estimating the wall properties is evaluated and consequential improvements to image quality are discussed. It was found that an asymmetric bistatic SAR geometry accurately extracts the refractive index and thickness of a wall. The method is applicable to both cluttered environments and non-parallel wall trajectories without loss of accuracy. Applying a compensation for refraction in the SAR imagery results in better positional accuracy but does not necessarily result in better image focusing. Volumetric multistatic image formation benefits from applied refraction compensation. SAR image formation, and in particular volumetric image formation, can be significantly accelerated via a spatially variant basebanding technique followed by zero padding. Spatially variant basebanding is sub optimal when applied to a Through-Wall radar scenario where there is a visible wall signature in the image. Keywords: Through-Wall radar, Multistatic radar, Multidimensional signal processing, Electromagnetic propagation, Radar imagi

The Development of Computational Tools for Theoretical Predictions in Particle Physics at the Large Hadron Collider

The Large Hadron Collider (LHC) experiments are an excellent tool for the improvement of our knowledge of the Standard Model and the examination of Beyond Standard Model theories. Nonetheless, to maximise the learning-potential of the LHC, clear and precise theoretical predictions are needed, for both the Standard Model and its extensions, to allow critical comparison of these models with data. In particular, given the complexity of the collision environment at the LHC, and the expansive nature of many parameter spaces of Beyond Standard Model theories, computational programs to perform theoretical calculations are increasingly required. The work presented in this thesis fits this role, it is focused on two computational programs developed with the aim of producing such theoretical predictions for LHC phenomenology in two key areas. These are the precision Standard Model predictions of transverse momentum spectra for a wide class of processes at the LHC, and Beyond Standard Model predictions for the decay widths of as-yet undiscovered particles in the context of supersymmetry. Chapter 1 presents a brief chronology and review of the Standard Model. Fol- lowing this, the work reported in this thesis is split into two parts, focused on the two main projects undertaken. Chapters 2, 3 and 4 describe the development of the SoftSusy decay calculator program to determine the partial widths and branching ratios of supersymmetric and Higgs particles in the Minimal Supersymmetric Standard Model and the Next-to-Minimal Supersymmetric Standard Model. The theoretical and phenomenological background, methodology, assumptions, and the vast array of decay modes calculated by the program are described. This is followed by details of the extensive validation of the decay calculator program and a selection of results. Chapter 5 begins the second part of the thesis, providing theoretical background for Chapters 6 and 7, which discuss the newly-developed reSolve program, designed to undertake the theoretically-demanding calculations associated with transverse momentum resummation for a wide range of LHC processes. Details of the methods, assumptions, validation and results for channels so far included are all provided, these show excellent agreement with previous theoretical results and experimental data. Both projects are then summarised in Chapter 8. Further information is provided in the appendices; Appendix A presents explicitly all formulae incorporated into the SoftSusy decay calculator pro- gram; whilst Appendix B provides further details on the theoretical underpinning of the transverse momentum resummation calculations performed by the reSolve program.This work was supported mainly by an STFC PhD Studentship. This work has been partially supported by STFC consolidated grant ST/L000385/1, with further help from the Department of Applied Mathematics and Theoretical Physics and the Cambridge Philosophical Society. In addition a portion of this work was completed whilst supported by a KITP Graduate Fellowship from The Kavli Institute for Theoretical Physics, University of California Santa Barbara via the National Science Foundation under Grant No. NSF PHY-1748958 along with the Gordon and Betty Moore Foundation

Moving Target Detection with Modified Logarithm Background Subtraction and Its Application to the GF-3 Spotlight Mode

Spaceborne spotlight SAR mode has drawn attention due to its high-resolution capability, however, the studies about moving target detection with this mode are less. The paper proposes an image sequence-based method entitled modified logarithm background subtraction to detect ground moving targets with Gaofen-3 Single Look Complex (SLC) spotlight SAR images. The original logarithm background subtraction method is designed by our team for airborne SAR. It uses the subaperture image sequence to generate a background image, then detects moving targets by using image sequence to subtract background. When we apply the original algorithm to the spaceborne spotlight SAR data, a high false alarm problem occurs. To tackle the high false alarm problem due to the target’s low signal-to-noise-ratio (SNR) in spaceborne cases, several improvements are made. First, to preserve most of the moving target signatures, a low threshold CFAR (constant false alarm rate) detector is used to get the coarse detection. Second, because the moving target signatures have higher density than false detections in the coarse detection, a modified DBSCAN (density-based spatial-clustering-of-applications-with-noise) clustering method is then adopted to reduce false alarms. Third, the Kalman tracker is used to exclude the residual false detections, due to the real moving target signature having dynamic behavior. The proposed method is validated by real data, the shown results also prove the feasibility of the proposed method for both Gaofen-3 and other spaceborne systems

Databook for human factors engineers. Volume 2 - Common formulas, metrics, definitions

Human factors engineering manual including mathematical formulas, nomographs, conversion tables, units of measurement, and nomenclature

The Black Book of Quantum Chromodynamics

The LHC (Large Hadron Collider) will serve as the energy frontier for high-energy physics for the next 20 years. The highlight of the LHC running so far has been the discovery of the Higgs boson, but the LHC programme has also consisted of the measurement of a myriad of other Standard Model processes, as well as searches for Beyond-the-Standard-Model physics, and the discrimination between possible new physics signatures and their Standard Model backgrounds. Essentially all of the physics processes at the LHC depend on quantum chromodynamics, or QCD, in the production, or in the decay stages, or in both. This book has been written as an advanced primer for physics at the LHC, providing a pedagogical guide for the calculation of QCD and Standard Model predictions, using state-of-the-art theoretical frameworks. The predictions are compared to both the legacy data from the Tevatron, as well as the data obtained thus far from the LHC, with intuitive connections between data and theory supplied where possible. The book is written at a level suitable for advanced graduate students, and thus could be used in a graduate course, but is also intended for every physicist interested in physics at the LHC

The Black Book of Quantum Chromodynamics

The LHC (Large Hadron Collider) will serve as the energy frontier for high-energy physics for the next 20 years. The highlight of the LHC running so far has been the discovery of the Higgs boson, but the LHC programme has also consisted of the measurement of a myriad of other Standard Model processes, as well as searches for Beyond-the-Standard-Model physics, and the discrimination between possible new physics signatures and their Standard Model backgrounds. Essentially all of the physics processes at the LHC depend on quantum chromodynamics, or QCD, in the production, or in the decay stages, or in both. This book has been written as an advanced primer for physics at the LHC, providing a pedagogical guide for the calculation of QCD and Standard Model predictions, using state-of-the-art theoretical frameworks. The predictions are compared to both the legacy data from the Tevatron, as well as the data obtained thus far from the LHC, with intuitive connections between data and theory supplied where possible. The book is written at a level suitable for advanced graduate students, and thus could be used in a graduate course, but is also intended for every physicist interested in physics at the LHC

The Fifteenth Marcel Grossmann Meeting

The three volumes of the proceedings of MG15 give a broad view of all aspects of gravitational physics and astrophysics, from mathematical issues to recent observations and experiments. The scientific program of the meeting included 40 morning plenary talks over 6 days, 5 evening popular talks and nearly 100 parallel sessions on 71 topics spread over 4 afternoons. These proceedings are a representative sample of the very many oral and poster presentations made at the meeting.Part A contains plenary and review articles and the contributions from some parallel sessions, while Parts B and C consist of those from the remaining parallel sessions. The contents range from the mathematical foundations of classical and quantum gravitational theories including recent developments in string theory, to precision tests of general relativity including progress towards the detection of gravitational waves, and from supernova cosmology to relativistic astrophysics, including topics such as gamma ray bursts, black hole physics both in our galaxy and in active galactic nuclei in other galaxies, and neutron star, pulsar and white dwarf astrophysics. Parallel sessions touch on dark matter, neutrinos, X-ray sources, astrophysical black holes, neutron stars, white dwarfs, binary systems, radiative transfer, accretion disks, quasars, gamma ray bursts, supernovas, alternative gravitational theories, perturbations of collapsed objects, analog models, black hole thermodynamics, numerical relativity, gravitational lensing, large scale structure, observational cosmology, early universe models and cosmic microwave background anisotropies, inhomogeneous cosmology, inflation, global structure, singularities, chaos, Einstein-Maxwell systems, wormholes, exact solutions of Einstein's equations, gravitational waves, gravitational wave detectors and data analysis, precision gravitational measurements, quantum gravity and loop quantum gravity, quantum cosmology, strings and branes, self-gravitating systems, gamma ray astronomy, cosmic rays and the history of general relativity