Software to predict the optical sorting of particles in a standing-wave laser interference field

In this paper, we propose a novel approach to reduce the noise in Synthetic Aperture Radar (SAR) images using particle filters. Interpretation of SAR images is a difficult problem, since they are contaminated with a multiplicative noise, which is known as the “Speckle Noise”. In literature, the general approach for removing the speckle is to use the local statistics, which are computed in a square window. Here, we propose to use particle filters, which is a sequential Bayesian technique. The proposed method also uses the local statistics to denoise the images. Since this is a Bayesian approach, the computed statistics of the window can be exploited as a priori information. Moreover, particle filters are sequential methods, which are more appropriate to handle the heterogeneous structure of the image. Computer simulations show that the proposed method provides better edge-preserving results with satisfactory speckle removal, when compared to the results obtained by Gamma Maximum a posteriori (MAP) filter.

SCATMECH is a library of object-oriented C++ computer codes originally developed for disseminating models for polarized light scattering from surfaces and aerosols and for diffraction from gratings. The pySCATMECH package has been developed as an interface to the SCATMECH library, simplifying use of the codes and allowing for more rapid development of software for these applications.

Deep subwavelength RF imaging with atomic Rydberg sensors has overcome fundamental limitations of traditionalantennas and enabled ultra-wideband detection of omni-directional time varying fields all in a compactform factor. However, in most applications, Rydberg sensors require the use of a secondary strong RF referencefield to serve as a phase reference. Here, we demonstrate a new type of Rydberg sensor for Angle-of-Arrival(AoA) sensing which utilizes subwavelength imaging of standing wave fields. By placing a metallic plate withinthe Rydberg cell, we can determine the AoA independent of the strength of incoming RF field and without requiringa secondary strong RF phase reference field. We perform precision AoA measurements with a roboticantenna positioning system for 4.2, 5.0, and 5.7 GHz signals and demonstrate a 1.7◦ polar angular resolutionfrom 0◦ to 60◦ AoA and 4.1◦ over all possible angles.

Although Rydberg atom-based electric field sensing provides key advantages over traditional antenna-based detection, it remains limited by the need for a local oscillator (LO) for low-field and phase resolved detection. In this work, we demonstrate the general applicability of closed-loop quantum interferometric schemes for Rydberg field sensing, which eliminate the need for an LO. We reveal that the quantum-interferometrically defined phase and frequency of our scheme provides an internal reference that enables LO-free full 360 degree-resolved phase sensitivity. This internal reference can further be used analogously to a traditional LO for atom-based down-mixing to an intermediate frequency for lock-in-based phase detection, which we demonstrate by demodulating a four phase-state signal broadcast on the atoms.

This dataset contains a collection of HH and VV interferograms collected with the JPL Airborne system UAVSAR. The interferogram cover various regions: - Winnipeg, Canada -Kenaston, Canada -Stuttgard, Arkansas, USA The data has been used to study the impact of NISAR quasi-quad pol mode on the computation of the ionospheric phase screen. The data are provided in a GDAL format and can be opened and handled using Python. The research was carried out at the Jet Propulsion Laboratory, California Institute of Technology © 2020. All rights reserved, under a contract with the National Aeronautics and Space Administration (80NM0018D0004)

Improving the bandwidth of Rydberg atom-based receivers is an ongoing challenge owing to the long-lived Rydberg state lifetimes that limit the refresh rate of ground state atoms.In particular, the LO-based Rydberg mixer approach allows for bandwidths into the few-MHz range.Here we use heterodyne detection of the Rydberg atom receiver probe laser to separate the negative and positive sidebands that originate from distinct six wave mixing processes in order to investigate their individual bandwidths.We experimentally confirm the prediction that the negative sideband exhibits a higher bandwidth than the positive sideband.We further explore the effect of coupling and probe laser Rabi frequency on the bandwidth, which we find to be in good agreement with our model. We achieved a maximum experimental (and theoretical) bandwidth of about 11 (11)~MHz and 3.5 (5)~MHz for the negative and positive sidebands, respectively, from the -3dB roll-off point for optimized field parameters.This work provides insight into the bandwidth-limiting features of Rydberg atom receivers and points the way towards further optimization of their response.

,GUI-based software coded in PYTHON to automate image stitching and alignment processes from a set of tile images for the high throughput image analytics by implementing a series of algorithms: 1) deskewing the image acquired in an oblique view angle, 2) row alignment of the geometrically drifted image due to acquisition errors by detecting the crop row using Hough Transformation, and 3) options for omnidirectional overlap trimming and resizing.,,