A5105511232- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Computational Physics and Python Applications
- Neutrino Physics Research
- Cosmology and Gravitation Theories
- Radar Systems and Signal Processing
- Direction-of-Arrival Estimation Techniques
- Antenna Design and Optimization
- Target Tracking and Data Fusion in Sensor Networks
- Atomic and Subatomic Physics Research
- Advanced Adaptive Filtering Techniques
- Advanced SAR Imaging Techniques
- Black Holes and Theoretical Physics
- Distributed and Parallel Computing Systems
- Distributed Sensor Networks and Detection Algorithms
- Nuclear reactor physics and engineering
- Astrophysics and Cosmic Phenomena
- Underwater Acoustics Research
- Nuclear Physics and Applications
- Scientific Research and Discoveries
- Noncommutative and Quantum Gravity Theories
- Radiation Therapy and Dosimetry
University of California, Santa Barbara
2023-2025
University of California System
2024-2025
University of Antwerp
2024
Institute of High Energy Physics
2023-2024
A. Alikhanyan National Laboratory
2024
University College London
2016
Royal National Orthopaedic Hospital NHS Trust
2016
Sensors (United States)
2002-2005
Technology Service Corporation (United States)
1971-1976
RAND Corporation
1961-1968
In many applications, the practical usefulness of adaptive arrays is limited by their convergence rate. The adaptively controlled weights in these systems must change at a rate equal to or greater than external noise field (e.g., due scanning radar if step scan not used). This problem most severe with large number degrees adaptivity and situations where eigenvalues covariance matrix are widely different. A direct method weight computation, based on sample field, has been found provide very...
This paper reviews the principles of adaptive radar in which both spatial (antenna pattern) and temporal (Doppler filter) responses system are controlled adaptively. An senses angular-Doppler distribution external noise field adjusts a set parameters for maximum signal-to-interference ratio optimum detection performance. A gradient technique control array/filter weights is described shown to generate asymptotically approach values. Simulation results illustrate convergence rate systems...
The ability of an AMTI (airborn moving target indication) radar to reject clutter is often seriously degraded by the motion radar. An adaptive receiving array can compensate for platform and provide excellent performance. Scattering from aircraft structure also distort antenna patterns reduce capability. technique described here adapt element weights near-field scatterers excitation errors. Another important advantage null out discrete active interference sources without significantly degrading
A method of estimating the angle arrival a signal at an array sensors in external noise environment is outlined. The development based on maximum likelihood estimator and leads naturally to adaptive sum difference beams which null sources. An algorithm for arrival, outputs adaptively distorted differnce beams, shown perform well presence sidelobe and/or main beam interference.
One type of phased-array radar current interest employs an array separate receiving elements, each followed by individual amplifier. These signals are combined coherently to form one or more beams for searching, tracking, performing both functions simultaneously. This paper presents approach the theory angle measurement with a phased this type. In one-dimensional problem considered here, antenna consists linear antenna-amplifier elements. The receiver-noise-limited case is considered, in...
In a coherent search rader, the pulse-to-pulse Doppler shift of signal is generally not known priori. Given distribution this parameter, best test variable for detection average likelihood ratio with respect to target frequency. Most radars employ maximum-likelihood detector, that is, bank independent filters, detection. The average-likelihood and tests are compared here Rayleigh amplitude distribution. It shown that, over wide range false-alarm probabilities, performances two do differ...
This paper deals with the cumulative detection probability of a search radar when it is scanning uniformly. that target, approaching at constant radial velocity, detected least once by time reaches given range, as distinguished from more common blip-scan ratio (a single-scan probability). It shown for constant-velocity targets range cumulative-detection varies cube root power-aperture product, rather than fourth root. Curves probability, function normalized are three different target...
In order to explore the performance improvement potential of applying adaptive array technology airborne radar systems, Naval Research Laboratory produced a database which enables development/evaluation algorithms requiring both spatial and temporal degrees freedom. A summary analyses utilizing this is presented. set be evaluated described. It includes three realizations linear combiner: joint-domain optimum algorithm, cascaded space-time algorithm time-space algorithm. The interference...
Sequential detection procedures, which may be used with phased-array radars, can provide a significant improvement in search capability as compared to uniform scanning. This paper discusses the cumulative probability (the that an approaching target is detected before it reaches given range) obtained two-step sequential test, first described by Finn [6]. In this pulse transmitted each beam position. If threshold crossing observed any range cell, second of higher energy and returns threshold....
The properties of an adaptive array antenna, including transient response rate and control loop noise, depend on the intensity external noise field. This dependence can be reduced by envelope hard limiting in loops, without degrading performance array.
A bstract The Light Dark Matter eXperiment (LDMX) is an electron-beam fixed-target experiment designed to achieve comprehensive model independent sensitivity dark matter particles in the sub-GeV mass region. An upgrade LCLS-II accelerator will increase beam energy available LDMX from 4 8 GeV. Using detailed GEANT4-based simulations, we investigate effect of increased on capabilities separate signal and background, demonstrate that veto methodology developed for GeV successfully rejects...
As part of its HL-LHC upgrade program, the CMS collaboration is replacing existing endcap calorimeters with a high-granularity calorimeter (CE). The new sampling unprecedented transverse and longitudinal readout for both electromagnetic hadronic compartments. Due to compactness, intrinsic time resolution, radiation hardness, silicon has been chosen as active material regions exposed higher levels. sensors are fabricated 20 cm (8") wide hexagonal wafers segmented into several hundred pads...
The properties of an adaptive array antenna, including transient response rate and control loop noise, depend on the intensity external noise field. dependence can be reduced by 1-bit digitization real imaginary parts signals from which envelopes in loops are formed. This done without degrading performance array.
The direct simulation of external noise fields containing a large number discrete sources or interference that is continuously distributed in angle requires the generation independent random variables per sample array input. A method simulating exactly statistics an arbitrary Gaussian field at input to <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</tex> -element with only described.
Abstract A novel method to reconstruct the energy of hadronic showers in CMS High Granularity Calorimeter (HGCAL) is presented. The HGCAL a sampling calorimeter with very fine transverse and longitudinal granularity. active media are silicon sensors scintillator tiles readout by SiPMs absorbers combination lead Cu/CuW electromagnetic section, steel section. shower reconstruction based on graph neural networks it makes use dynamic reduction network architecture. It shown that algorithm able...