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Vigorous and transformative investigation of the millimeter/submillimeter sky at high sensitivity and high resolution has benefitted from the recent completion five years of science from the Atacama Large Millimeter/submillimeter Array (ALMA). ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), NSC and ASIAA (Taiwan), and KASI (Republic...
We show the existence of an inherent handedness (spin) of evanescent-electromagnetic-waves which is fundamentally locked to the direction of propagation (momentum). It is universal and accompanies evanescent waves in total internal reflection, waveguides/fibers and surface-states. The hallmark of the recently discovered quantum spin hall (QSH) state of matter is the existence of electronic surface...
A novel computational electromagnetic method developed with discrete exterior calculus (DEC) (M. Desbrun et al., arXiv:math/0508341) on simplicial mesh is presented. As is well known, differential forms can been used to recast Maxwell's equations in a more succinct fashion, which completely separate metric-free and metric-dependent components. Instead of dealing with vectorial field as finite difference...
This paper investigates high frequency (HF) radiation capabilities of a two mast, canonical ship using characteristic mode theory and distributed array design. Two ring arrays of 18 electrically small dipole radiators (.1λ) are designed to be circularly distributed between a two mast canonical shipboard structure. Consequently, the entire superstructure becomes the main radiator where its radiative...
In this paper, a low-power CMOS AC-to-DC full-bridge rectifier with a switch for piezoelectric transducers is presented. It consists of two NMOS and two PMOS transistors, which are configured to operate as a full-bridge rectifier along with an Op-Amp-based switch control circuit which is connected to a PMOS transistor of the main full-bridge rectifier. With a load of 45KΩ, the output rectifier voltage...
The focus of this paper is to present a low profile, and highly efficient monopole antenna integrated with artificial magnetic conductor (AMC) using textile materials with a compact footprint for off-body communication in the ISM 5.8 GHz band. In addition, effect of structural deformation in terms of antenna bending on the performance of monopole antenna with and without AMC reflector is examined...
This paper provides a brief overview of the current Green Bank Telescope science program, and an update on technical developments performed since 2010.
In this paper, the design of a microstrip patch antenna for microwave sensing of sand production in petroleum pipelines is presented. Two antennas are designed in order to cover the entire sensing regime (gas to liquid including large percentages of brine) common to petroleum production lines. The antennas are designed to operate at ∼5GHz. The antenna intended for sensing with low-loss fluids (gas...
A uniformly distributed family of circular topology is analyzed using probabilistic methods to find mean valued radiation characteristics in the near field (Fresnel zone). Linear arrays with circular and spherical distributions of one, two and three dimensional spaces are compared using this analysis to obtain benchmark performance metrics. This novel method also determines the statistical effects...
Continuous patient monitoring in the normal daily life can be realized with body-worn wireless and fully passive sensors. We have previously developed and optimized a novel Wireless Resistive Analog Passive (WRAP) sensor technology with inductive link between a secondary Printed Spiral Coil (PSC) attached to the body and a wearable scanner with the primary PSC to continuously monitor physiological...
In this paper, we are presenting a dual polarization massive multiple input multiple output (MIMO) panel array antenna with beam steering capability. This design includes a Ka band (31.8 GHz to 33.46 GHz) 4×8 microstrip patch planar array with good isolation between the polarizations which is a desired parameter for a massive MIMO antenna systems. We are controlling input excitations and phases of...
While mobile health (mHealth) provides tremendous opportunity to monitor patient health, continuous monitoring of various physiological data can be enhanced with body-worn sensors. In this paper, we demonstrate impedance phlebography (IPG) based pulse sensing using inductively coupled Wireless Resistive Analog Passive (WRAP) sensors that are prototyped on paper using inkjet printing (IJP) technique...
The development of modern communication devices for the latest technologies such as 5G has brought the millimeter wave technology into the spotlight because it offers higher data rates and bandwidth. Since highly directional transmissions are necessary for communication in these frequencies due to high path loss and atmospheric absorption, the application of adaptive antennas are inevitable. However,...
This paper presents a fully integrated low-power wearable respiration monitoring system using a pyroelectric transducer. Many chronic respiratory diseases such as asthma and apnea are leading causes of death worldwide which are even more critical for premature neonatal infants. Currently, the diagnosis of apnea requires the infants to go through overnight clinical sleep analysis, also known as polysomnography...
The science goals set by the Science Working Group for the ngVLA include study of star and planet formation, imaging the Milky Way and nearby galaxies, study of galaxy formation, cosmology etc. In order to achieve these targeted studies, the ngVLA proposal calls for about 300 antennas spread over a large geographical area, mainly in the western New Mexico region. The proposed array will consist of...
Non causal filtering or smoothing is an important signal processing technique. In this work we implement a new non causal filter and apply it to whistler mode ray tracing platform. This smoothing technique is highly resistant to outliers; hence it helps on increasing the accuracy of the numerical results.
The Climate-Monitoring Microwave Radiometer (CliMMR) will address the requirements for measuring long-term trends in atmospheric temperature with excellent stability and linearity, and very low antenna sidelobe contributions. CliMMR would also serve as an on-orbit calibration standard for weather-satellite instruments. Small satellites in carefully chosen non-sun-synchronous orbits could compile a...
For point-to-point backhaul systems located in a vegetated residential area, the base-station transmitter is located close to the surrounding rooftops; the propagation takes place over the rooftops and through the canopy of the trees. The receivers, in many cases, are also located close to the surrounding rooftops or well below them. The objective of the present paper is to use the Torrico-Bertoni-Lang...
Rotman lenses have long served as analog beam forming networks (BFNs) to support linear scanning arrays. However, most lens designs have large electrical size which limits their uses in compact transceiver systems. In this paper, we aim to design a compact lens structure by folding the lens into two layers, and using coupling slots as transition. The proposed designed structure will reduce the overall...
Rainfall estimation based on radar measurements has been addressed by using parametric algorithms such as Z-R relation. However, such empirical relations may not be sufficient to capture the space-time variability of precipitation. In this paper, we introduce a DMLP-based machine learning model for rainfall estimation by using multiple layers to capture the complex abstractions of radar reflectivity...
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