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A Stochastic Programming Approach to the Design Optimization of Layered Physical Protection Systems.
Abstract not provided.
Physical Layer Entropy Analysis for Physical Unclonable Functions
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Apparatus and methods for managing packet transfer across a memory fabric physical layer interface
An apparatus and method for managing packet transfer between a memory fabric having a physical layer interface higher data rate than a data rate of a physical layer interface of another device, receives incoming packets from the memory fabric physical layer interface wherein at least some of the packets include different instruction types. The apparatus and method determine a packet type of the incoming packet received from the memory fabric physical layer interface and when the determined incoming packet type is of a type containing an atomic request, the method and apparatus prioritizes transfer of the incoming packet with the atomic request over other packet types of incoming packets, to memory access logic that accesses local memory within an apparatus.
Slides for LDRD review presentation of 18A12-131FP, "Cyber-Secure Physical Layer Security in Millimeter Wave Communications"
Objective Enhance cyber security, protection, and assurance of advanced mmWave wireless communications in the presence of unauthorized devices and intruders with novel capabilities within the physical layer. Significance Wireless communications using millimeter waves (mmWave) in the GigaHertz (GHz) band is a key new technology that will play a major role in the 5th Generation (5G) wireless networks. Cyber-physical solutions for other frequency bands are not directly applicable to mmWave technologies. We propose to validate the hypotheses that: 1) communications can be better protected from eavesdropping and cyber intrusion with security features built within the mmWave physical layer, 2) User authentication can be conducted in a non-intrusive manner and with high probability of success by the use of physical channel variations of mmWaves which get scattered by a human body.
Enhancing Physical Layer Security for NOMA Transmission in mmWave Drone Networks
Note that the abstract was earlier approved with INL/CON-18-45291. This paper was provided after presentation of the material in the Asilomar conference. Physical layer security (PLS) is critically important for emerging wireless communication networks to maintain the confidentiality of the information of legitimate users. In this paper, we investigate enhancing PLS in an unmanned aerial vehicle (UAV) based communication network where a UAV acting as an aerial base station (BS) provides coverage in a densely packed user area (such as a stadium or a concert area). In particular, non-orthogonal multiple access (NOMA) together with highly-directional multi-antenna transmission techniques in mmWave frequency bands are utilized for improving spectral efficiency. In order to achieve PLS against potential eavesdropper attacks, we introduce a protected zone around the user region. However, limited resource availability refrain protected zone being extended to cover the entire eavesdropper region. Hence, we propose an approach to optimize the protected zone shape (for fixed area) at each UAV-BS hovering altitude. The associated secrecy performance is evaluated considering the secrecy outage and sum secrecy rates. Numerical results reveal the importance of protected zone shape optimization at each altitude to maximize NOMA secrecy rates. Index Terms—5G, drone, HPPP, mmWave, non-orthogonal multiple access (NOMA), physical layer security (PLS), UAV.
Physical Layer Security for mmWave Drone Links with NOMA
Unmanned aerial vehicle (UAV) based communication networks have recently received significant attention in providing broadband coverage during temporary events and disaster situations. Non-orthogonal multiple access (NOMA) and millimeter-wave (mmWave) transmission are two prominent technologies for these networks to realize high-throughput communication links. While delivering broadband connection, physical layer security remains as an essential feature of the network to maintain the confidentiality of the information.In this study, we investigate the physical layer security for a UAV based communication network involving mmWave NOMA transmission. In particular, we consider optimization of location and shape of a protected zone around the user region, which is assumed to be free from any eavesdropper, to further enhance the secrecy rates of the network.
Precoder Design for Physical-Layer Security and Authentication in Massive MIMO UAV Communications
Supporting reliable and seamless wireless connectivity for unmanned aerial vehicles (UAVs) has recently become a critical requirement to enable various different use cases of UAVs. Due to their widespread deployment footprint, cellular networks can support beyond visual line of sight (BVLOS) communications for UAVs. In this paper, we consider cellular connected UAVs (C-UAVs) that are served by massive multiple input-multiple-output (MIMO) links to extend coverage range, while also improving physical layer security and authentication. Here, we consider Rician channel and propose a novel linear precoder design for transmitting data and artificial noise (AN). We derive the closed-form expression of the ergodic secrecy rate of CUAVs for both conventional and proposed precoder designs. In addition, we obtain the optimal power splitting factor that divides the power between data and AN by asymptotic analysis. Then, we apply the proposed precoder design in the fingerprint embedding authentication framework, where the goal is to minimize the probability of detection of the authentication tag at an eavesdropper. In simulation results, we show the superiority of the proposed precoder in both secrecy rate and the authentication probability considering moderate and large number of antenna massive MIMO scenarios.
Quantifying the Impact of Vertical Resolution on the Representation of Marine Boundary Layer Physics for Global-Scale Models
Abstract While GCM horizontal resolution has received the majority of scale improvements in recent years, ample evidence suggests that a model’s vertical resolution exerts a strong control on its ability to accurately simulate the physics of the marine boundary layer. Here we show that, regardless of parameter tuning, the ability of a single-column model (SCM) to simulate the subtropical marine boundary layer improves when its vertical resolution is improved. We introduce a novel objective tuning technique to optimize the parameters of an SCM against profiles of temperature and moisture and their turbulent fluxes, horizontal winds, cloud water, and rainwater from large-eddy simulations (LES). We use this method to identify optimal parameters for simulating marine stratocumulus and shallow cumulus. The novel tuning method utilizes an objective performance metric that accounts for the uncertainty in the LES output, including the covariability between model variables. Optimization is performed independently for different vertical grid spacings and value of time step, ranging from coarse scales often used in current global models (120 m, 180 s) to fine scales often used in parameterization development and large-eddy simulations (10 m, 15 s). Uncertainty-weighted disagreement between the SCM and LES decreases by a factor of ∼5 when vertical grid spacing is improved from 120 to 10 m, with time step reductions being of secondary importance. Model performance is shown to converge at a vertical grid spacing of 20 m, with further refinements to 10 m leading to little further improvement. Significance Statement In successive generations of computer models that simulate Earth’s atmosphere, improvements have been mainly accomplished by reducing the horizontal sizes of discretized grid boxes, while the vertical grid spacing has seen comparatively lesser refinements. Here we advocate for additional attention to be paid to the number of vertical layers in these models, especially in the model layers closest to Earth’s surface where climatologically important marine stratocumulus and shallow cumulus clouds reside. Our experiments show that the ability of a one-dimensional model to represent physical processes important to these clouds is strongly dependent on the model’s vertical grid spacing.
Physical layer Authentication of Wired Networks (PAWN) Final Technical Report
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Edge and Scrape-off-Layer Physics for NSTX-U (Final Report)
U.S. Department of Energy (DOE) supported work at Lodestar Research Corporation under grant DE-FG02-02ER54678 is summarized in this final report. The research conducted under this grant addressed key scientific issues associated with the plasma confinement and fusion energy experimental devices NSTX and its upgrade NSTX-U located at Princeton Plasma Physics Laboratory. Harnessing the energy that is released in fusion reactions would provide a safe and abundant source of power to meet the growing energy needs of the world population. Lodestar investigated the important cm-scale region near the edge of these devices where hot plasma, close to one million degrees, meets material surfaces in what is known as a scrape-off layer (SOL). This critical region is subject to plasma turbulence and plasma flows which must be understood to optimize fusion performance on future machines. The work employed theoretical and theory-based computational models for validation and applied the models to understand experimental results.
Electro-osmo-dialysis through nanoporous layers physically conjugated to micro-perforated ion-exchange membranes: Highly selective accumulation of trace coions
This study explores theoretically and numerically the phenomenon of counter-flow accumulation of trace coions during electro-osmo-dialysis through composite membranes containing nanoporous and perforated ion-exchange layers. The combination of charged nanopores and perforations allows electroosmosis, and ion concentration polarization appears near the ion-exchange layer. Accumulation of trace coions occurs because their advective and electromigration flow velocity components have opposite signs and are locally compensating in depletion regions where electric fields are high. This local compensation of flow components can give rise to high accumulation factors (>1000 in some cases) for trace coions at some distance from the interface between the nanoporous and ion-exchange layers. Moreover, the extent of this accumulation depends on the trace-coion diffusion coefficient. The resulting selectivity between different coions might serve as a basis for environmentally friendly separation of ionic species such as synthetic peptides or rare-earth elements. For example, a periodic process might include accumulation followed by species release into smaller volumes of solution. For both rare-earth ions and peptide-like species, the accumulation selectivity between ions with small differences in mobilities depends on system parameters such as nanoporous-layer thickness, distance between the perforations, and the zeta potential of the nanopore surface. Here, the use of optimal values of these membrane parameters may enable tuning of the electro-osmo-dialysis system for separation of specific ions. Modelling reveals that despite inhomogeneous patterns of fluid and ion flows close to the nanoporous/perforated ion-exchange interface, at relatively short distances from this interface (less than half the distance between the perforations) all the flows become practically one-dimensional (1D). Similarly, the concentration profiles of trace coions also become 1D. The flow one-dimensionality at short distances from the current-polarized interface enables a simple 1D approximation that is useful for an approximate analysis of trends in this multi-parameter system.
Kinetic simulations of scrape-off layer physics in the DIII-D tokamak
Not Available
Physical Layer Security at a Point-to-Point MIMO System With 1-Bit DACs and ADCs
Low-resolution converters reduce the power consumption of wireless devices and help enable large energy-efficient arrays. In this letter, we evaluate the secrecy rate for the extreme case of 1-bit single-user multiple-input multiple-output systems following two signaling approaches. In the first method, the system uses discrete signaling. In the second, the system combines Gaussian signaling with artificial noise alongside power allocation. In the first case, we give a closed-form expression of the secrecy rate and propose an algorithm that provides near-optimal results for low signal-to-noise ratios (SNRs). Further, in the second scenario, depending on the channel state information, we suggest different precoding plans and derive a secrecy rate lower bound. At low SNR, power is allocated to the main signal. Only at high SNR is optimal power allocation effective. Moreover, knowing the eavesdropper channel greatly improves the system’s secrecy.
Mushy Layer Physics in Sea Ice Models [Slides]
Abstract not provided.
A Stochastic Programming Approach to the Design Optimization of Layered Physical Protection Systems - Presentation.
Abstract not provided.
A Stochastic Programming Approach to the Design Optimization of Layered Physical Protection Systems (ePRA).
Abstract not provided.
Physical layer authentication of electronic communication networks
A network authentication system can be configured for sampling a plurality of signal samples from a device on a network, providing the plurality of signal samples to a first machine-learned model that is configured to determine a device fingerprint based at least in part on the plurality of signal samples, and providing the device fingerprint to a second machine-learned model that is configured to classify the device based at least in part on the device fingerprint.