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We present polarisation profiles for 48 southern pulsars observed with the new 10-cm receiver at the Parkes telescope. We have exploited the low system temperature and high bandwidth of the receiver to obtain profiles which have good signal…

Astrophysics · Physics 2009-11-10 A. Karastergiou , S. Johnston , R. N. Manchester

I discuss the physics of polarization in models with early reionization. For sufficiently high optical depth to recombination the polarization is boosted on large scales while it is suppressed on smaller scales. New peaks appear in the…

Astrophysics · Physics 2016-08-30 Matias Zaldarriaga

A dielectric rod feed with a special radiation pattern of a tabletop form used for the compact range reflector is developed and analyzed. Application of this feed increases the size of the compact range quiet zone generated by the…

Instrumentation and Detectors · Physics 2014-01-28 Nikolay P. Balabukha , Alexey A. Basharin , Natalia E. Shapkina

THz photoconductive antennas are among the most popular devices for THz wave generation and detection. A novel and accurate circuit is proposed to model the performance of such antennas, especially those which are frequency dependant. The…

Applied Physics · Physics 2019-03-06 Fatemeh aghili , Ali Mahjoori

The optical conductivity of a polaronic charge carrier in the intermediate and strong-coupling regimes is calculated for a tight-binding electron using exact diagonalization. Two different simple models of the electron-phonon coupling are…

Condensed Matter · Physics 2007-05-23 M. Capone , W. Stephan

For smart clothing integration with the wireless system based on radio frequency (RF) backscattering, we demonstrate an ultra-high frequency (UHF) antenna constructed from embroidered conductive threads. Sewn into a fabric backing, the…

Signal Processing · Electrical Eng. & Systems 2017-10-09 Philip H. Gordon , Rex Chen , Huiju Park , Edwin C. Kan

The modal dispersion of waveguides often limits integrated photonic devices to operation with a single polarization state. This presents a challenge for sensing and spectroscopy applications, which often require polarization diversity over…

Inspired by the anisotropy of Doppler effect with wave propagations, we propose a new method to leverage one information symbol serving two users located in two geometrically orthogonal directions. Specifically in broadband wireless…

Signal Processing · Electrical Eng. & Systems 2020-07-15 Bingli Jiao

Optimization of strongly non-linear tightly coupled feeds attached to antennas is a challenging problem from a purely computational perspective. One can imagine that an optimization would (a) need to be in the time domain, and (b) has to be…

Optimization and Control · Mathematics 2023-04-25 Sean F. DePalma , Omkar H. Ramachandran , Leo C. Kempel , B. Shanker

A new method is presented for modeling the transformation between two polarimetric pulse profiles in the Fourier domain. In practice, one is a well-determined standard with high signal-to-noise ratio and the other is an observation that is…

Astrophysics · Physics 2007-05-23 Willem van Straten

We study a pattern forming instability in a laser driven optically thick cloud of cold two-level atoms with a planar feedback mirror. A theoretical model is developed, enabling a full analysis of transverse patterns in a medium with…

Optics · Physics 2017-11-08 W. J. Firth , I. Kresic , G. Labeyrie , A. Camara , T. Ackemann

We propose a novel beam model for radio pulsars based on the scenario that the broadband and coherent emission from secondary relativistic particles, as they move along a flux tube in a dipolar magnetic field, forms a radially extended…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Hong Guang Wang , Fei Peng Pi , Xiao Ping Zheng , Chun Lan Deng , Sai Qin Wen , Feng Ye , Kai Ying Guan , Yi Liu , Li Qing Xu

The Low Frequency Instrument on board the ESA Planck satellite is coupled to the Planck 1.5 meter off-axis dual reflector telescope by an array of 27 corrugated feed horns operating at 30, 44, 70, and 100 GHz. We briefly present here a…

This paper presents a method for the fast and accurate estimation of the gain pattern and maximum gain of an implanted antenna including the effect of the host body, under the assumption that the latter is electrically large. The estimation…

A device performing both the polarization-alignment and the wavelength selection is demonstrated by fabricated device. Waveguides incorporating Bragg gratings for polarization rotation and mode conversion having different widths are placed…

Characterization of the minute cosmic microwave background polarization signature requires multi-frequency, high-throughput precision instrument systems. We have previously described the detector fabrication of a 40 GHz focal plane and now…

In this paper, we present a numerical electromagnetic model of a focal plane array in combination with a multi-channel receiver. Initial experimental validation results are shown that confirm the expected predictions from the model.

Instrumentation and Methods for Astrophysics · Physics 2016-02-16 O. Iupikov

Predictions and measurements of a multimode waveguide interferometer operating in a fibre coupled, ``dual-mode'' regime are reported. With a 1.32 micrometer source, a complete switching cycle of the output beam is produced by a 10.0…

Optics · Physics 2009-11-13 Richard M. Jenkins , Andrew F. Blockley , J. Banerji , Alan R. Davies

Linear (spectro) polarimetry is usually performed using separate photon flux measurements after spatial or temporal polarization modulation. Such classical polarimeters are limited in sensitivity and accuracy by systematic effects and…

Optics · Physics 2010-05-28 Frans Snik , Theodora Karalidi , Christoph U. Keller

We consider the polarization properties of radiation emitted by relativistic charged particles while moving along the curved magnetic field lines in a pulsar manetosphere. We propose that the radiation emitted by positrons and electrons…

Astrophysics · Physics 2007-05-23 R. T. Gangadhara
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